Twin Turbo 400 Buildup- '89 Iroc-Z
06-28-2010, 06:29 PM
#451
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
I have near 15" vacuum on my gauge but another gauge I used said 13". Either way that should be more than enough. My 383 had more cam and probably less vacuum than this motor and never had a braking problem. Stock brakes were never great but felt better than my C5's do at this moment. I just need to give it time.
Rad i have is a ultra thick Griffin and from what I'm told its designed for more circle track cars running at 70-80 mph constantly. I need more airflow thru the rad for it to cool properly. I need to change it out or get alot more fan flow
Rad i have is a ultra thick Griffin and from what I'm told its designed for more circle track cars running at 70-80 mph constantly. I need more airflow thru the rad for it to cool properly. I need to change it out or get alot more fan flow
06-28-2010, 06:36 PM
#452
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
yea i know u musta had less vacume than me... bc my xfi280 was pulling 10-12" and my cam was way milder than yours... i wish she wasnt stolen on friday 
got a link to the griffin rad? ive heard of alot of ppl having issues with cooling if they have the intercooler in front of the rad. but im sure your rad is fine... you just need more air going through it. time to step up the fans
got a link to the griffin rad? ive heard of alot of ppl having issues with cooling if they have the intercooler in front of the rad. but im sure your rad is fine... you just need more air going through it. time to step up the fans
06-28-2010, 06:42 PM
#453
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Not sure what I"m going to run yet, but I need to get a shrouded fan setup. May try stock LS1 fans with shroud first as its cheap and I can even borrow one to try. May put one of my stock fans behind the intercooler to suck in more air. Either way its running alot hotter than I feel comfortable with and I want to be sure its just an air issue and nothing else.
Sorry to hear about the car, that sucks! I dont know what I'd do if that happened to me. Hope they find it
Sorry to hear about the car, that sucks! I dont know what I'd do if that happened to me. Hope they find it
06-28-2010, 10:35 PM
#454
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
how hot is it getting? mine is usually like 160-170 but in stop and go traffic in really hot weather it hits like 180-190. the high stall doesnt help either. do the LS1 fans bolt up to the stock 3rd gen system? or is it alot of work to get it to fit?
actually they did find it... found out today. but i have no idea wat shape the car is in... so im freakin out. im assuming the worst.
actually they did find it... found out today. but i have no idea wat shape the car is in... so im freakin out. im assuming the worst.
06-29-2010, 08:32 AM
#456
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Yeah it will reach over 200 deg fairly quickly and I will shut it off. I dont want to go higher than that. Most tell me 200 is not too hot, but I have been driving it before when it hit 200 and continued to rise until it was 220 and I had to pull over. I had the rad hose blow off at 221 before. Even on the highway it slowly rises until that temp so I cant really go anywhere. There is alot of heat around those turbos so it heats up the entire engine bay rather quickly.
Plan is to have more fan for more air flow, and to improve airflow thru the intercooler. I hope to make some more heat extractors inthe hood to possibly help rid the excess heat at idle. We shall see.
Dyno will be fun. I have yet to really dial in air fuel ratio to where I want it and to play with timing. I figure a few runs at various boost levels from 8-9psi then 14-15 and I'll beable to dial in the majority of my street driving. I would like to try the highest boost level that pump gas will handle just to see what this car is really capable of, but I dont want to hurt anything Its already put down 690 on 17psi on the mustang dyno thru my old very loose converter and running pig rich. I should have 750 in it at the same boost setting but the goal is to reach near 750 on 15 psi. It made 640 on just 12.5 psi with a better air fuel ratio, so if i can just lean it out abit more and hold that on higher boost, it should gain another 75 whp or so. Hoping for 100. I figure on 12.5 psi I could lay down 680 with better air fuel and few deg of timing.
Then I'd like to make another trip on race gas to try for 900whp. I doubt I have enough head/cam/turbo for 1000 but it would be nice to match this single turbo Supra we have running around up here.
Plan is to have more fan for more air flow, and to improve airflow thru the intercooler. I hope to make some more heat extractors inthe hood to possibly help rid the excess heat at idle. We shall see.
Dyno will be fun. I have yet to really dial in air fuel ratio to where I want it and to play with timing. I figure a few runs at various boost levels from 8-9psi then 14-15 and I'll beable to dial in the majority of my street driving. I would like to try the highest boost level that pump gas will handle just to see what this car is really capable of, but I dont want to hurt anything
Its already put down 690 on 17psi on the mustang dyno thru my old very loose converter and running pig rich. I should have 750 in it at the same boost setting but the goal is to reach near 750 on 15 psi. It made 640 on just 12.5 psi with a better air fuel ratio, so if i can just lean it out abit more and hold that on higher boost, it should gain another 75 whp or so. Hoping for 100. I figure on 12.5 psi I could lay down 680 with better air fuel and few deg of timing.Then I'd like to make another trip on race gas to try for 900whp. I doubt I have enough head/cam/turbo for 1000 but it would be nice to match this single turbo Supra we have running around up here.
07-04-2010, 05:22 PM
#457
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Car: 1991 Camaro Z28
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Re: Twin Turbo 400 Buildup- '89 Iroc-Z
I'm using a Lincoln Mark VIII fan and trust me, it moves a lot of air. You have to have heavy wire and big fuses and relays to power it. If you need a single fan that moves air like a mechanical fan, this is it. It is kinda big though so I'm not sure what your clearances are like with all that tubing under the hood.
07-04-2010, 09:03 PM
#458
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
What year lincoln? I have heard those are good fans and same thing about the cadillac fans. I may try one of those. Not sure yet, i havent looked into my fan options. I have plenty of room inthe radiator area
07-05-2010, 08:48 AM
#459
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Car: 1991 Camaro Z28
Engine: 357, Canfield heads, solid roller,
Transmission: Upgraded 03 Cobra T56
Axle/Gears: 9" 3.50 gears and Detroit Locker
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
I dont remember exactly what year it was. I know it was mid to late 90's. Mine is only a one speed fan. There are two speed fans as well. Just make sure you use nothing less than 10 guage wiring and have relays and fuses to handle 40 amps continuosly and almost 100 at start up.
07-05-2010, 01:44 PM
#460
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Also looking at a silverado truck rad and fan setup. Its around 17-18" tall but 34" wide. Huge dual fans. I might beable to lean it backwards abit to get my intake pipe to clear over the rad, but the width looks alittle wide for the thirdgen nose. I'll have to take some measurements.
07-05-2010, 01:55 PM
#461
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Car: 1991 Camaro Z28
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Transmission: Upgraded 03 Cobra T56
Axle/Gears: 9" 3.50 gears and Detroit Locker
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
I can tell you that a 34" radiator will not fit between the frame rails up front. I have an all aluminum 19.5" X 31" radiator that barely fits. I had to drill out the spot welds that hold the bottom radiator tray on and cut out the rest of it. I then had to drop build a bottom tray that is 2" or so lower. Where the factory bottom tray gets spot welded in makes it too narow to fit the 31" radiator. That second layer of sheet metal inside has to go.
07-05-2010, 02:25 PM
#462
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Yeah, i figured it would be tight since the stock rad is tight and its about 31" wide. Looks like i'll try to find a large single fan, maybe that lincoln fan. May also look at trying a set of shrouded LS1 fans, but not sure yet
07-05-2010, 08:32 PM
#463
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Hey Orr, I was wondering if your transmission cooler lines go through your radiator? Seeing as you have a high stall torque converter I was wondering if that is adding any heat to the radiator? Trucool makes a high capacity stand alone transmission cooler incase that could be part of your problem.
07-06-2010, 03:09 AM
#465
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Car: '74 Firebird, '84 vette
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Re: Twin Turbo 400 Buildup- '89 Iroc-Z
the Taurus from 90-95 has the same fan, and a little easir to find. This is the mother of all fans!
07-06-2010, 07:33 AM
#466
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
orr AWESOME car hope mines comes out sick like that when it's done i;m gonna be using the 1000hp becool kit and their fans draw 3400 cfm of air thru the radiator also something to look into http://www.becool.com/productsearch i'm gonna be running the 75038 fans
07-06-2010, 12:56 PM
#467
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Thanks guys. I will try one of the large single fans because the dimensions seems to fit my radiator well. I have some ideas to channel more air thru the front of the car to help cool at speed, since it didnt seem to get any better while driving. Still slowly rises til it hits abit over 200 deg and i dont want to drive anymore. I'll take it to 220 before shutting down but i just want it to hover at a certain point preferably below 190.
Its a time bomb. You have to drive to your destination quickly before it eventually overheats and you have to stop to cool down. Thankfully it can get to those destinations rather quickly so I still have some range
I do realize I need a new alternator. That stock unit just cant keep up with all the power demands from electric everything.
Its a time bomb. You have to drive to your destination quickly before it eventually overheats and you have to stop to cool down. Thankfully it can get to those destinations rather quickly so I still have some range
I do realize I need a new alternator. That stock unit just cant keep up with all the power demands from electric everything.
07-06-2010, 01:29 PM
#468
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Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Orr89RocZ:
I am using the BeCool 1000HP kit, but to be honest for the price I am sure there are better options out there. I am not completely satisfied with it. I have been running my car for a few weeks now and the temp stabilizes at 185-190 degrees in 95-100 degree weather. Keep in mind I don't use a thermostat and I have an electric Meziere water pump, so I have a pretty constant flow of water across the core. I do, however, like the spal fans that came with the BeCool kit.
I am using the BeCool 1000HP kit, but to be honest for the price I am sure there are better options out there. I am not completely satisfied with it. I have been running my car for a few weeks now and the temp stabilizes at 185-190 degrees in 95-100 degree weather. Keep in mind I don't use a thermostat and I have an electric Meziere water pump, so I have a pretty constant flow of water across the core. I do, however, like the spal fans that came with the BeCool kit.
07-06-2010, 01:36 PM
#469
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Car: '74 Firebird, '84 vette
Engine: 454 twin turbo, 350 HSR
Transmission: 4L80E, 700R4
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Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Have you done any cooling passage mods to the block at all? I used to have a lot more cooling issues on small blocks before I started plugging and drilling as described in the Bill Jenkins pro-stock small block book.
07-06-2010, 03:07 PM
#470
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Block is a dart SHP that came from a machine shop already done and ready to assemble. I do not know if anything was done to the block's passages. Heads/intake are as cast so no mods to the cooling ports there either.
Yeah, the price did not attract me. I have a CSR pump that is advertised at 35-37 gpm. I think Meziere or someone makes a 55 gpm rated pump. I was thinking of trying that one. I had a 170 t stat in it and the car stabilized at 190 in 40 deg weather but now that its near 90, it dont want to stabilize below 220 I took the stat out and it didnt make a difference. I know fan flow thru the rad is a problem but even at speed it didnt cool down so I think i am having problems getting air thru the intercooler?
I gotta play around with the fans and such. Maybe put a stocker behind the intercooler to pull air in and use the big Taurus/Lincoln single fan to pull air thru the rad. If that helps some, maybe look into the higher volume waterpump.
I am using the BeCool 1000HP kit, but to be honest for the price I am sure there are better options out there. I am not completely satisfied with it. I have been running my car for a few weeks now and the temp stabilizes at 185-190 degrees in 95-100 degree weather. Keep in mind I don't use a thermostat and I have an electric Meziere water pump, so I have a pretty constant flow of water across the core. I do, however, like the spal fans that came with the BeCool kit.
I took the stat out and it didnt make a difference. I know fan flow thru the rad is a problem but even at speed it didnt cool down so I think i am having problems getting air thru the intercooler?I gotta play around with the fans and such. Maybe put a stocker behind the intercooler to pull air in and use the big Taurus/Lincoln single fan to pull air thru the rad. If that helps some, maybe look into the higher volume waterpump.
07-06-2010, 04:32 PM
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Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Based on my experience with the 55gpm Meziere electric pump, I'm not convinced you'll see much of a difference. Mind you, I am also running one of their 50gpm pumps for my AWIC water tank. Granted they move more water than a conventional pump when the car is stationary and idling, I don't think water flow is your issue. Forgive me for not reading the entire thread, but if your still using the stock radiator core, that's a big area of concern. It sounds to me like your underhood temps are too high, air flow to the primary radiator is restricted by the AAIC, and that you don't have enough fan to overcome the stacked resctriction you are seeing with your current arrangement.
07-06-2010, 05:09 PM
#472
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Let me bring you up to speed. Long thread, but main page is pretty much updated 90%.
I have a big thick griffen rad that I believe was spec'd for circle track racing. its about 27" wide by 15.5" tall and 3-4" thick. I think your right in the fact that I dont have enough airflow thru the rad. I have plans to remedy this.
My underhood temps are very hot but not sure what I can do about that. More heat extraction would be nice but the turbos are already poking thru the hood so heat is coming out of the car.
I have a big thick griffen rad that I believe was spec'd for circle track racing. its about 27" wide by 15.5" tall and 3-4" thick. I think your right in the fact that I dont have enough airflow thru the rad. I have plans to remedy this.
My underhood temps are very hot but not sure what I can do about that. More heat extraction would be nice but the turbos are already poking thru the hood so heat is coming out of the car.
07-06-2010, 06:47 PM
#473
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
The Meziere 55gpm water pump made a difference in my car over the factory pump. I bought it mainly for the horsepower put the side effect was more efficient cooling in stop and go traffic with the A/C on. I noticed that right away. With Orr it might be a combination of things that it will take to bring his temperatures under control. I will be interested to see how the big single fan works over the factory dual fans.
07-06-2010, 10:49 PM
#474
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
I already have the one fan on a seperate relay so swapping in one single wont take too long to do. Hope i have the amp rating needed but if not its not hard to swap in a new relay to get the fan to work.
If it makes no difference I'll go with plan B, which is a different set of dual fans for even more flow. I can always swap in the stock fans again and try other things like a different rad or higher flow from the pump, but I dont think thats the big contributor here. Too hot under hood temps around the rad means less cooling capability. Lots to play with I guess. Just cant wait to race again and run the times it should.
If it makes no difference I'll go with plan B, which is a different set of dual fans for even more flow. I can always swap in the stock fans again and try other things like a different rad or higher flow from the pump, but I dont think thats the big contributor here. Too hot under hood temps around the rad means less cooling capability. Lots to play with I guess. Just cant wait to race again and run the times it should.
07-09-2010, 02:41 PM
#475
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Car: 1991 RS L99 1992 Z28 L98 Heritage
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Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Go kick the Sh** out of that Supra running around there!!!!!!! Good Luck
07-09-2010, 04:33 PM
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Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Orr--
When you put in the AAIC, what did you do to replace the original flashing around the front of the radiator? The original plastic piece wouldn't fit around the AAIC, so I assume you fabricated some sort of duct to replce it. With mine I noticed that I had a great deal of recirculation once I removed the factory piece, not to mention a severe decrease in cooling at highway speeds.
I am wondering if you're suffering from a recirc issue.
When you put in the AAIC, what did you do to replace the original flashing around the front of the radiator? The original plastic piece wouldn't fit around the AAIC, so I assume you fabricated some sort of duct to replce it. With mine I noticed that I had a great deal of recirculation once I removed the factory piece, not to mention a severe decrease in cooling at highway speeds.
I am wondering if you're suffering from a recirc issue.
07-09-2010, 04:43 PM
#477
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Your are probably right. I have no ducting there anymore. I just took out the fog lights and that plastic ducting/shields and replaced it with an intercooler. There is nothing behind the intercooler to the rad.
These cars are bottom feeders I hear, so the air coming in the front may be blocking some of the bottom air feeding capability. Could be recirculating. I have to play around with my rad/intercooler arrangement. I have plans to lean the rad either forward or backward and replace the inner plastics to force air straight back thru.
Fat chance. One popped up that I did not know about that made 1044whp on a mustang dyno that I made 690 on Just discusting. However, I was on pump gas with no real tuning and medium boost. Put me on race gas and let me tune it, things could get interesting as boost goes up.
These cars are bottom feeders I hear, so the air coming in the front may be blocking some of the bottom air feeding capability. Could be recirculating. I have to play around with my rad/intercooler arrangement. I have plans to lean the rad either forward or backward and replace the inner plastics to force air straight back thru.
Go kick the Sh** out of that Supra running around there!!!!!!! Good Luck
Just discusting. However, I was on pump gas with no real tuning and medium boost. Put me on race gas and let me tune it, things could get interesting as boost goes up.
07-09-2010, 08:57 PM
#478
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Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Thought I would provide you with some shots of what I did to replace the factory ducting. Maybe you could do something like this. I found doing this and sealing up the gaps around the radiator core in the core support almost eliminated recirc.
07-09-2010, 10:29 PM
#479
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
I have a similar layout to that. Large inner gap between rad and the big intercooler. I was going to do some sheetmetal enclosures to channel air to the rad to eliminate any turbulence of air or recirculation. I was going to cap off the sides like you did as well as build a top sheild to keep air from rising up over, sorta like where the factory TPI air intake box ducting sits.
Since these cars are suppose to be bottom feeders, with the top and sides blocked off, air will be forced to go thru the rad.
The only problem I can see is underhood air flow. Once air gets pulled thru the fan, where does it go? Back to the engine bay but without any venting, how can it escape? Plus you have even hotter air from the motor being generated and just sitting in there. That only further adds to the overheating issue, so I wonder if I can vent my hood more to allow for some kind of air flow thru the engine bay?
Stock LS1 Trans am cars dont have a bumper opening. I have a 99 TA daily driver. Air is feed in from underneath with the air dam just like a thirdgen. The LS1 rad/fans are leaning backwards. So it forces the fan exhaust downward and I wonder if it just joins up with the air stream just moving underneath the car at speed. So its just a smooth cooling flow. Underhood doesnt seem to vent any heat but not that much heat is generated from that motor like my turbos.
So I was considering leaning the radiator backwards abit. We shall see.
Since these cars are suppose to be bottom feeders, with the top and sides blocked off, air will be forced to go thru the rad.
The only problem I can see is underhood air flow. Once air gets pulled thru the fan, where does it go? Back to the engine bay but without any venting, how can it escape? Plus you have even hotter air from the motor being generated and just sitting in there. That only further adds to the overheating issue, so I wonder if I can vent my hood more to allow for some kind of air flow thru the engine bay?
Stock LS1 Trans am cars dont have a bumper opening. I have a 99 TA daily driver. Air is feed in from underneath with the air dam just like a thirdgen. The LS1 rad/fans are leaning backwards. So it forces the fan exhaust downward and I wonder if it just joins up with the air stream just moving underneath the car at speed. So its just a smooth cooling flow. Underhood doesnt seem to vent any heat but not that much heat is generated from that motor like my turbos.
So I was considering leaning the radiator backwards abit.
We shall see.
07-09-2010, 11:52 PM
#480
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Re: Twin Turbo 400 Buildup- '89 Iroc-Z
I didn't include a picture of it, but I fabricated a lid for mine as well. I also use a plain filler panel to cover the top of the opening for a more factory look. Together they completely seal off the front of my primary radiator and force it to draw in fresh outside air. As for where the air goes after it goes through the radiator, it goes out the bottom of the car. Once at speed, the under car airflow helps draw it out more efficiently. One of the biggest advantages to running a cowl hood is that it helps extract radiated engine heat when the car is sitting still. At speed, a low pressure area is developed at the windshield that helps draw out even more air.
Leaning the radiator back won't necessarily make it more efficient. Typically it is done due to space constraints and not as an improvement to efficiency. The only way it helps in efficency is if it places the cooling fins of the core more perpendicular to the airflow. I have been designing large (68L on up) diesel engines applications for 6 years now as an engineer for Cummins and the most challenging aspect of my design work has always been recommending the appropriate cooling system to our customers. Cooling systems are very complex, but typically boil down to two things (1) heat rejection into the coolant & (2) the cooling systems ability to remove that heat. When I run into a cooling system that is not performing adequately, it usually boils down to three things (1) improperly sized core/or too many passes, (2) recirculation, or (3) insufficient airflow through the core. All of these assume the pump is moving enough coolant without restriction and that the system deairates properly once the thermostat opens.
Given you are not directing the airflow through the core with the appropriate deflectors, I would start there before going to different fans or modifying the placement of the radiator. Base on your previous post, I think you'll be surprised to find out that recirculation is a majority your problem. Besides, GM saw a necessity to direct airflow through the radiator with the plastic ducts so you can bet removing them will have adverse effects on the airflow through the radiator.
Leaning the radiator back won't necessarily make it more efficient. Typically it is done due to space constraints and not as an improvement to efficiency. The only way it helps in efficency is if it places the cooling fins of the core more perpendicular to the airflow. I have been designing large (68L on up) diesel engines applications for 6 years now as an engineer for Cummins and the most challenging aspect of my design work has always been recommending the appropriate cooling system to our customers. Cooling systems are very complex, but typically boil down to two things (1) heat rejection into the coolant & (2) the cooling systems ability to remove that heat. When I run into a cooling system that is not performing adequately, it usually boils down to three things (1) improperly sized core/or too many passes, (2) recirculation, or (3) insufficient airflow through the core. All of these assume the pump is moving enough coolant without restriction and that the system deairates properly once the thermostat opens.
Given you are not directing the airflow through the core with the appropriate deflectors, I would start there before going to different fans or modifying the placement of the radiator. Base on your previous post, I think you'll be surprised to find out that recirculation is a majority your problem. Besides, GM saw a necessity to direct airflow through the radiator with the plastic ducts so you can bet removing them will have adverse effects on the airflow through the radiator.
Last edited by Kendol; 07-09-2010 at 11:59 PM.
07-10-2010, 10:08 PM
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Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Recirculation just means that the air passing through the core (i.e. heated air) is redirected or recirculated back into the front of the radiator. This leads to a increasing engine coolant temp as the recirc air gets hotter and hotter. Typically recirc is caused by large air gaps beside or underneath the radiator core, or large openings (i.e. like the ones generated if you remove the factory air duct) that allow air to feed back into the radiator from the engine compartment.
07-30-2010, 06:40 PM
#483
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Hey, sorry if this has already been covered, but how did you go about cutting the front bumper/support ? Id like to stick my IC in the same spot you did but obviously the support needs to be cut out. Did you cut it out, put the IC in, and then build another bracket to connect the two sides back up?
Thanks.
Thanks.
07-30-2010, 09:20 PM
#484
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
The front crash bar/bumper support I just cut straight down from the two frame rails. My intercooler fits perfectly between the two so that was a big help. I welded 2 tabs on each side for the mounts and thats it. There is nothing else behind the crash bar. Front nose is open from IC back to rad
07-30-2010, 11:29 PM
#485
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
So does that compromise the integrity of the car at all? I think you'd just lose the one buffer plastic thing and some metal right?
Im just tryin to think if its "ok" for my application because its a street car. I guess at worse I could just reinforce it with some heavy gauge steel.
Im just tryin to think if its "ok" for my application because its a street car. I guess at worse I could just reinforce it with some heavy gauge steel.
08-02-2010, 05:31 PM
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Re: Twin Turbo 400 Buildup- '89 Iroc-Z
car is awesome man, looks mean with the turbos poking out through the hood like that... im surprised that rearend is holding up, ive heard of guys grenading them with their 4 banger s10's lol
Last edited by Maverick2664; 08-02-2010 at 08:57 PM.
11-19-2010, 02:06 PM
#487
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Re: Twin Turbo 400 Buildup- '89 Iroc-Z
i appologise for not reading the whole thread but i wws wondering are you running oil coolers ? also have you played with the car without a hood to eleminate the under the hood heat i know tis isn't a fix but it would also look badass with no hood .lol
what your iat look like ? might try wrapping the turbo an headers to help with the under the hood temps also you could shoot the intercooler with n02 while under boost this may have two benifits lower iat temps the blow by may reduce your over all temps by freezing the radiater while boosting . jus sum ideas if you haven't tried these .
what your iat look like ? might try wrapping the turbo an headers to help with the under the hood temps also you could shoot the intercooler with n02 while under boost this may have two benifits lower iat temps the blow by may reduce your over all temps by freezing the radiater while boosting . jus sum ideas if you haven't tried these .
11-19-2010, 05:23 PM
#488
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Dont have an oil cooler now but am considering going to one. Overheating has been solved with good fans from LS1. Shroud helped alot.
Havent driven it without a hood, its illegal in PA and dont think that was ever the problem. I wrapped the downpipes and drivers header since its on the brake booster so I wanted to keep that cool. May wrap the passenger header now.
NO idea what IATs are. I dont have a sensor to accurately measure it but I plan on adding one. I need to do some work over winter which will be next week and christmas/newyears weeks
Had some lifter and/or rocker noise last few times I drove it, so tearing down the hotside/intake/valvecovers and doing an inspection.
Also had some bad blow by issues under boost, not sure what its from. May be leaking thru the manifold, may be a damaged ring. I plan to do comp test and leak down test while hotside is off.
Sold the T60 turbos and will be going with T70s from Masterpower so they bolt right in.
Got some Morel lifters to replace the LS7's if the LS7's are collapsed. I doubt it but morels are suppose to be the best lifter out there so I may just drop them in.
Plan on getting it properly tuned for once and hopefullly see what the car can do. Been running a basic street track tune but never fully dialed it in.
Havent driven it without a hood, its illegal in PA and dont think that was ever the problem. I wrapped the downpipes and drivers header since its on the brake booster so I wanted to keep that cool. May wrap the passenger header now.
NO idea what IATs are. I dont have a sensor to accurately measure it but I plan on adding one. I need to do some work over winter which will be next week and christmas/newyears weeks
Had some lifter and/or rocker noise last few times I drove it, so tearing down the hotside/intake/valvecovers and doing an inspection.
Also had some bad blow by issues under boost, not sure what its from. May be leaking thru the manifold, may be a damaged ring. I plan to do comp test and leak down test while hotside is off.
Sold the T60 turbos and will be going with T70s from Masterpower so they bolt right in.
Got some Morel lifters to replace the LS7's if the LS7's are collapsed. I doubt it but morels are suppose to be the best lifter out there so I may just drop them in.
Plan on getting it properly tuned for once and hopefullly see what the car can do. Been running a basic street track tune but never fully dialed it in.
11-19-2010, 08:51 PM
#489
Supreme Member
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
i'm working my way to a turbo'd small block i'm reading more of thiss thread for info on my build .my last car was a 50trim srt4 that run 12's at 113 mph i'm wanting 10's -11's with this car an be daily driven .i used meth for cooler iat an more octane . thanks for the informative thread .
12-06-2010, 09:46 PM
#490
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Car: '05 Audi A6
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Re: Twin Turbo 400 Buildup- '89 Iroc-Z
The very fact that you cannot decipher what I'm saying tells me everything. If your going to cap it at 15-psi on the very same engine, the larger turbo will have to be capped earlier on in the RPM because it flows more air ON AVERAGE because of it's impeller speed, not to mention the wastegate needing to be bigger, so what is so hard to understand about that? During 1 through 15-psi, one can only squeeze so much air through a two inch (if that) intake valve, so how exactly can a larger turbo get more air through that valve when the smaller one is already at full volume up until that point lmao....?
Again, nothing changes the fact that 15-psi is still 15-psi. I mean, do I have to get Eric Marshall and Bob Bailey here for you to understand this? Bigger compressor wheels flow more air, so at a given (the same) RPM, the bigger turbo will always flow more, because psi will be more than the smaller turbo can dish out at the very same RPM level. By the way, you don't just slap on a larger turbo and run in the nine's on the very same setup as the small one, you need larger injectors, larger wastegate, not to mention larger stall, because it will lag, not to mention tune. Speaking of which, the last time I checked, replacing a small turbo with a much larger one, in respect to tuning, the cells most looked at, and changed, are up high in the grid, for a reason, because that is where the additional boost becomes a factor....
Your argument is that a larger turbo can squeeze more air through a two inch intake valve during 1 through 15-psi, when the stock turbo is already at full volume during that time. Full volume, meaning, you CAN'T get more air into the combustion chamber. You will need to prove that you can get more air in with factual proof, because that is impossible. The benefits of the larger turbo over the smaller one is that it takes less resistance (meaning, you can run a gigantic intercooler, you can run ported heads, bigger cam, and 4" intake), and make the same amount of boost the smaller one would need to WITH resistance, because the larger turbo obviously flows more air to begin with. Not to mention, the larger turbo lasting longer up top. So explain yourself, show me how a larger turbo can squeeze more air than a stock turbo into a stock engine, up until 15-psi, when the stock turbo has already filled up the volume.
Again, nothing changes the fact that 15-psi is still 15-psi. I mean, do I have to get Eric Marshall and Bob Bailey here for you to understand this? Bigger compressor wheels flow more air, so at a given (the same) RPM, the bigger turbo will always flow more, because psi will be more than the smaller turbo can dish out at the very same RPM level. By the way, you don't just slap on a larger turbo and run in the nine's on the very same setup as the small one, you need larger injectors, larger wastegate, not to mention larger stall, because it will lag, not to mention tune. Speaking of which, the last time I checked, replacing a small turbo with a much larger one, in respect to tuning, the cells most looked at, and changed, are up high in the grid, for a reason, because that is where the additional boost becomes a factor....
Your argument is that a larger turbo can squeeze more air through a two inch intake valve during 1 through 15-psi, when the stock turbo is already at full volume during that time. Full volume, meaning, you CAN'T get more air into the combustion chamber. You will need to prove that you can get more air in with factual proof, because that is impossible. The benefits of the larger turbo over the smaller one is that it takes less resistance (meaning, you can run a gigantic intercooler, you can run ported heads, bigger cam, and 4" intake), and make the same amount of boost the smaller one would need to WITH resistance, because the larger turbo obviously flows more air to begin with. Not to mention, the larger turbo lasting longer up top. So explain yourself, show me how a larger turbo can squeeze more air than a stock turbo into a stock engine, up until 15-psi, when the stock turbo has already filled up the volume.
Idk if anybody did this already and sorry for the late reply, but here's the physics nuke:
pV=nRT aka ideal gas law, where
p= absolute pressure (15gpsi+14.7apsi= ~30apsi)
V= Volume (assume 750ml using static volume)
n= the amount of elemental mass (assume only oxygen given in moles)
R= gas constant(8.314472(15)Joules/(mol*Kelvin)
T= absolute temperature (~310Kelvin)
Basic math tells us that if we lower do something to one side of the equation we have to do the same to the other side to keep it correct. So if we bring down the temp, T, (be it with an intercooler, methanol, using a bigger, slower turbo, or bringing in cold air) then something on the OTHER side must come DOWN or something on the SAME side must go UP.
“R” can’t go up (constant), so either the “p” drops, “V” drops, or “n” goes up. In other words, either pressure drops (no can do because we have a turbo blowing), volume drops (not doable either because the volume is set in cast iron and steel), so “n” goes up, which is the AMOUNT OF ACTUAL GAS MOLECULES FOR A GIVEN PRESSURE. More gas molecules can react with more gasoline molecules for more power.
All of the above listed, cold air induction, A/C systems, a fast draining propane cylinder that ices up… they all use this principle…
Raising “n” raises “p”, that raises “T”
Raising “V” raises “p”, that raises “T”
And vise versa all the way around…
Play with it and you’ll see how it works (BTW, don’t forget R is a constant) Anybody see something dumb, feel free to amend..
12-06-2010, 10:11 PM
#491
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
I guess i'll find out for you...15 psi on T70's vs 15psi on T60s. I believe i'll gain power because the T70 is more efficient (I think) than the T60s so like you said, lower temp, denser charge, more power.
01-16-2011, 11:47 AM
#492
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Car: 91 GTA
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Re: Twin Turbo 400 Buildup- '89 Iroc-Z
For a all the guys arguing about turbo sizing, it would help if you did a search on Thermodynamic state diagrams and then execute one on the model of the system you have in your car. This will reveal the entropy of the turbo sizing and the effects it has on your plant system.
My hats off to the OP I have seen your car around the site for a while. It is impressive. I am thinking of making the dive from NA to FI and came across this build thread for the first time. Inspirational to say the least.
My hats off to the OP I have seen your car around the site for a while. It is impressive. I am thinking of making the dive from NA to FI and came across this build thread for the first time. Inspirational to say the least.
01-16-2011, 01:28 PM
#493
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Re: Twin Turbo 400 Buildup- '89 Iroc-Z
Fat chance. One popped up that I did not know about that made 1044whp on a mustang dyno that I made 690 on
Just discusting. However, I was on pump gas with no real tuning and medium boost. Put me on race gas and let me tune it, things could get interesting as boost goes up.
01-17-2011, 11:05 AM
#494
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
I'm using a Lincoln Mark VIII fan and trust me, it moves a lot of air. You have to have heavy wire and big fuses and relays to power it. If you need a single fan that moves air like a mechanical fan, this is it. It is kinda big though so I'm not sure what your clearances are like with all that tubing under the hood.
I can also agree with him, these fans are insane large tho. Ive seen them and i contimplated using one. but the price of these things can be hard to handle. Most of the time keep ur eyes peeled on ebay or craigslist. My friend is running on on his stang and it is veryyyy popular upgrade on fords. The 2 speed fan flows a whopping 4000-5000CFM, but take a BUTTLOAD of power to get her going and keep her going. This would be the best option since it will still be cheaper than an aftermarket high flow setup. Ive been pricing cooling systems and ive found that spal or other brands seem to work best but also cost a good bit.
Ive also stuffed a ford 31"x19"x3" into my 87 firebird. It was not an easy task. I removed the entire lower rad stupport and built my own whats roughly 1.5-2" lower and use thin 1"x1"x1/16" mild steel square tubing. I then had to cut 3" into the pass side stock subframe and box'd it in to shift the rad over 3". mostly this was due to the ford having the lower inlet on the bottom driver side which hit the power steering box.My rad fans however (due to limited space) im running dual 12" proform fans for about 3000cfm with a derale fan harness with NPT sensor. Then im running dual trans coolers B&M super cooler 24,000 GVW inline with a permacool all aluminum with dedicated 8" fan. I dont think my fans will be good enough but im willing to try them and see since i didnt have a problem with the stock dual fan setup.
01-17-2011, 11:13 AM
#495
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
i know you already figured it out but just throwing it out with the mark iV fan. ALso i thought u had already wrapped the headers? or was it just the down pipes? i would wrap the headers definitly and put some heat shrouds on the turbos. wrap and cover everything under the hood is what i would do.
01-17-2011, 11:13 AM
#496
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
ive used both the ford fan which is a great single fan (have one on my rodeo) and i just used a set of dual fans off a superchargered bonnville on my tahoe and they cool great, judging by the ac vent temps, better than the belt driven fan that sounded like an air plane.
i used 3 relays to wire them like the ls1's do for high and low. both can be had in junk yards around here for 20$.
i used 3 relays to wire them like the ls1's do for high and low. both can be had in junk yards around here for 20$.
01-17-2011, 11:54 AM
#497
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
orr, where did u get your pin on hood from and how much? i might have to sell my RAM air II hood since i might need a taller scoop to fit the BBF with a dropped air cleaner from what i have seen they run about 400$ and then the shipping kills ya.
from what i have seen they run about 400$ and then the shipping kills ya.
01-17-2011, 12:24 PM
#498
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
The LS1 fans with shroud did the trick for me. I put in a 140 amp alternator and wired the fans to switches and havent had a problem yet. Ran fine at 184 deg temp with no t-stat, pure water and low mid 80's deg summer heat.
I was gonna do the mark IV fan setup but I didnt want a big single. LS1's fit good enough for my rad size and I got them for a good price.
Hood is a harwood 4" cowl. Fit leaves alot to be desired. Found it local for 300 bucks I think it was. It works for now but I really want to redo the system so i can put a stock style hood back on, or the SS hood. Since I had to cut the hood to fit, I dont feel bad cutting a 300 dollar hood instead of a 450+ shipping hood.
I was gonna do the mark IV fan setup but I didnt want a big single. LS1's fit good enough for my rad size and I got them for a good price.
Hood is a harwood 4" cowl. Fit leaves alot to be desired. Found it local for 300 bucks I think it was. It works for now but I really want to redo the system so i can put a stock style hood back on, or the SS hood. Since I had to cut the hood to fit, I dont feel bad cutting a 300 dollar hood instead of a 450+ shipping hood.
01-17-2011, 01:33 PM
#499
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
d@mn, ive been looking at cowl hoods for my BBF setup. the carb sits 2" above the top of my firewall and then u need to add the height of the air cleaner which is prob another 2" or so.
your running straight water? what about adding a additive? DEI makes some new stuff, called radiator relief, it offers quicker warmups and dropped coolant temps.
http://www.summitracing.com/parts/DEI-040104/
which is prob another 2" or so. your running straight water? what about adding a additive? DEI makes some new stuff, called radiator relief, it offers quicker warmups and dropped coolant temps.
http://www.summitracing.com/parts/DEI-040104/
01-17-2011, 02:04 PM
#500
Re: Twin Turbo 400 Buildup- '89 Iroc-Z
forgot, I do have some water wetter additive stuff. Seems to help alittle bit but didnt really cure my problem like it advertised. Still reached 220 deg and never stopped rising. The fans did the trick.
You may beable to find a low rise air cleaner or run no cleaner at all. No problem doing that. Glasstek makes a 5-6" cowl too
Also forgot to mention, since I tore the setup down this winter and put it all back together with the larger turbos, I wrapped everything. Downpipes always been wrapped but both headers are now wrapped unlike before.
You may beable to find a low rise air cleaner or run no cleaner at all. No problem doing that. Glasstek makes a 5-6" cowl too
Also forgot to mention, since I tore the setup down this winter and put it all back together with the larger turbos, I wrapped everything. Downpipes always been wrapped but both headers are now wrapped unlike before.
