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I'm stuck debating cam vs heads vs both. I want to keep my investment low but I also don't want to do this work to end up at the exact same blockade to performance. The question comes down to whether the biggest problem is the cam or the heads.
Since my birthday is tomorrow, I've been more willing than usual to consider spending on this project. Those Fastburn heads sure look like a perfect replacement to my L98 Aluminum heads (62cc, D-port exhaust, the right springs on the 19300955 version).. Intake flow is way better but the exhaust is only about 20 cfm better so I'm not sure it would be the magic bullet.
So the question is, would going to a bigger cam have a reasonable chance of improving my setup or will I end up with the same barrier? I've just always had the gut feeling that this cam is a big piece of the problem but I know these heads aren't exactly the best things that could be on here. Since I'm going to buy an intake, I should consider the heads now because the Fastburns support Vortec intakes as well.
As a reminder, my current cam is a hyd roller 224/224, 114 sep and around .530" lift. Further research today found several builds online using a nearly identical cam on full weight cars going way down into the 9's with Fastburn or similar heads. I'm leaning towards intake/heads plus the new turbo. If there is still an issue it will be easy to pull the Steath Ram intake and do a cam swap. There wouldn't be anything else it could be at that point. If I can get more power at lower boost, I might even get away with leaving my current fuel system as it is.
Re: Turbo Iroc - Round Four - 5.3 (Edit: Staying Gen1, new PT7675)
After visiting my friend who builds tons of turbo cars, who is also baffled at my results, I made the decision to just go after the common link I'm seeing to cars that are stuck in the 11's.. my 113 heads. The cam is certainly large enough to do the work. Now I just have to get my hands on a Vortec friendly intake (or tpi base). I think could get away with a base and Siamese runners, especially with the boost helping things along. But I think the HSR style intakes would give better overall performance and certainly be easier to work on.
Also ordered 3" intercooler piping. I'm on my way to 6 seconds somehow! I'm hoping to have this thing running good by September so I can take it to the Clayton 1/2 mile and try to outrun my GT-R's 152.4 mph.
Re: Turbo Iroc - Round Four - 5.3 (Edit: Staying Gen1, new PT7675)
Originally Posted by ZZ3Astro
After visiting my friend who builds tons of turbo cars, who is also baffled at my results, I made the decision to just go after the common link I'm seeing to cars that are stuck in the 11's.. my 113 heads. The cam is certainly large enough to do the work. Now I just have to get my hands on a Vortec friendly intake (or tpi base). I think could get away with a base and Siamese runners, especially with the boost helping things along. But I think the HSR style intakes would give better overall performance and certainly be easier to work on.
Also ordered 3" intercooler piping. I'm on my way to 6 seconds somehow! I'm hoping to have this thing running good by September so I can take it to the Clayton 1/2 mile and try to outrun my GT-R's 152.4 mph.
for the cost of a vortec tpi base , just buy the hsr , its a much much better intake for making power
Re: Turbo Iroc - Round Four - 5.3 (Edit: Staying Gen1, new PT7675)
Heads first....then cam with the larger turbine. Larger turbine will like more conventional na type cams due to less pressure ratio across the turbine/less restriction to flow
Re: Turbo Iroc - Round Four - 5.3 (Edit: Staying Gen1, new PT7675)
Made a deal for a vortec base Stealth Ram! I had agreed to buy a vortec TPI base and then started reading up on the Scoggin D base.. wow it's only 20 cfm more than the stock base. Then I'd have to scrape up larger runners. Boy these aftermarket TPI upgrade parts are getting hard to find and super pricey. Stealth Ram is definitely light-years ahead of that.
So the configuration will is now going to be:
PT7675 CEA BB Gen2 (supports 1000hp on V8)
Fast Burn 210cc heads GM# 19300955
Holley Stealth Ram Vortec
224/224 @ .050, 114 sep, .539"/.531 Hyd Roller (existing cam)
Can I finally go 10s?????
If this car finally makes me happy with performance, I could see spending for a nice ECM so I can put in the 80e. Love that Holley system but it's always a bad sign when someone sells you the power cable separately for $60. A sign that it's going to get expensive quick.
Re: Turbo Iroc - Round Four - 5.3 (Edit: Staying Gen1, new PT7675)
It never ran on the track with 600.. it would have been around 500-520 rwhp at the last track visit, but burned a plug wire during the first pass an only went around 95 mph (1/8). Before that track day, I was always fighting fueling issues. It did go 98 mph in the 1/8th. The 600 whp was on race gas with about 22 psi. Would have been fun to run it down the track but the turbo was just killing itself at that point.
Looking at my flow numbers for everything, I really feel good about the new combination matching nicely. Everything on the air flow side is good for right around 1000 hp so it should be pretty happy to make ~800 flywheel. And yes I realize these are some of the exact parts you guys were telling me to go with (especially the intake). I do listen, I just didn't want to spend the money on this car. What made me change course, in no small part, was driving the car after it sat for a few months. It tried to kill me and I was suddenly interested again. Go figure.
Re: Turbo Iroc - Round Four - 5.3 (Edit: Staying Gen1, new PT7675)
Well it is just about time for me to post a rant. The heads are here and I'm quite disappointed in a few things. It's been a very long time since I've bought heads and last time I did they were probably made in the USA. These look like they were made by three year olds in China. Metal flakes everywhere, scuffed up on the outside, D-ports crooked and casting edges that looked like they were drawn by the same three year olds.
I can clean up the metal flakes (all from the drill-thru of the rocker stud holes into the intake runner) with a lot of work.. I'd pull the studs and chase every thread, really worried about metal flakes jammed between the valve and seat inside the runners too. And the heads will probably perform just fine... and the headers will cover up the crappy edges of the casting.. but on principle I'm tempted to not accept these.
Note metal shavings at top right - bottom of rocker stud hole
Just an annoyance here... why are the ports not perfectly parallel?
Another annoyance... why is the milled edge not straight and sharp? Also it's not really milled. The final finish looks like it was done by hand.
Almost every rocker stud hole has this hanging at the top of the intake runner.
Re: Turbo Iroc - Round Four - 5.3 (Edit: Staying Gen1, new PT7675)
Originally Posted by Orr89RocZ
How do you know it makes killer power? You havent run or dyno'd it yet lol
And i would return those heads and buy something more quality. Dart shp 180 is good for the money and so is jegs/profiler
cause ive been out driving it before and after the turbo
quality is a hell of alot better then the pics of what u did buy as well
seats guides all the threaded holes, ports were right on out of the box , only copmplaint was the small sensor temp port int he head instead of a large port, and they dont tell u the intake valve is moved so u need to use adjustable guide plates
Re: Turbo Iroc - Round Four - 5.3 (Edit: Staying Gen1, new PT7675)
I really wish I hadn't made these headers D-port flanged. In theory they will work on other port types but with less sealing surface. I'm going to put this subject in the back of my mind for the evening.. it's really ruining my day right now.
Re: Turbo Iroc - Round Four - 5.3 (Edit: Staying Gen1, new PT7675)
After much research and consultation, I'm going to try to make these heads work. If nothing else, the cost to ship them back, then pay for shipping for another brand is going to add up, and I could end up with the same problem. Solution? Brought them to my cylinder head guy for inspection, valve seal testing and cleanup. I'm going to clean up the ports with a carbide bit and some 80 grit fan wheels. Kind of a stage 1 porting but quick and dirty. That is assuming he doesn't find any issues with valves, seats and sealing.
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
One step closer.. nose is now off in preparation for 3" intercooler tubing. Cleaned up the shop and built a temporary work bench for parts to go on. I've decided to pull the engine and transmission since the heads are delaying the project by a couple of weeks. I'm going to inspect a couple of bearings, check rear main seal, etc on the engine. Also I'm going to replace third gear clutches in the transmission and I'm putting my slightly looser Vigilante converter back in.
Engine should be out in the next couple of days. I figured it would give me a chance to clean up everything end touch up paint. Might as well play like it's a whole new engine since it should certainly run like a different one!
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
I did have relocation brackets on the lower control arms but the brackets were welded on my 9 bolt that broke. They definitely seemed to help. Also I have dual adjustable QA1s and relocated battery to rear. I want to do coil cover conversion on the front if I ever do a K Member. It's worth mentioning I have factory struts up front and they are worn, so they are somewhat like a drag strut in extension now.
I haven't done any lightening to this car but my previous 86 I had a ton of weight off the front and extra in back. It really hooked well!
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
Thats good to know. I'm going to start doing the suspension over in my car soon. I've got Hotchkis subframe connectors, BMR torque arm, Hotckhis lower control arms and panhard bar. I need to go through and replace the bushings, springs and shocks. Those are all original and are worn out.
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
Yeah me too.. everything is original and (now) battered. I need bushings, boxed LCA's, struts, you name it. I've always felt though that a good worn out suspension on a third gen sport coupe is one of the best street hooking suspensions out there though. My 86 was 100% stock suspension except I put one of those 'helper' springs (made to go over standard shocks) inside of the right rear spring to stop a wheel hop issue. On drag radials it would cut 1.5x lights all day lol. Oh, also a 12 bolt but no relocation of the LCAs. Stock torque arm too!
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
Not sure people realize what they're looking at when they look at that turbo, it is a work of art. I had no idea you were still running only 2 1/2" intake tubing all this time, as upping it to 3" alone will make a world of difference. Do something about those rims though...
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
The smaller intake tubing forced the turbo to work that much harder generating higher boost pressure through an extremely restricted TPI intake. With a 3" intake tubing diameter, he would be able to push the same amount of air, if not more, than he already was but with much less boost pressure resistance. I'll go out on a limb and say that this is why the Precision turbo went bad as fast as it did, as well as why he couldn't match the C4 Corvette he always compared himself with running the same turbo and TPI setup...
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
I know I had to have been at the limit with 675-700 hp but I'm pretty sure he was running 2.5" on the vette as well. In any case I know 3" will work much better for me.
And yes those heavy wheels.. just need to come up with money and the right choice. If I keep the car long enough it will have some light weight wheels on it.
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
The world is definitely your oyster when it comes to rims/tires. I mentioned rims because you need to stuff some serious tire out back for what you're planning, especially if you expect it to keep up with the GTR on the highway from a roll. Looking forward to the transmission mods though Steve, definitely get the whole process on video if you could...
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
Yeah I'm going to video the transmission stuff this time but I don't think there will be many changes. I need to find out what Dana thinks I need. I hope to go into the 4L80e in a few months and will do a full build on it using a similar kit from Dana.
Speaking of transmissions, mine is out and all I have left to do is pull the starter and engine mount bolts and I will finally be able to start the actual work.
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
Originally Posted by ZZ3Astro
Poll:
Solid mounts "needed" at the 800 hp level or NO?
u never have to have solid mounts , just good quality motor and trans mounts
ask yourself this how much vibration can u take inside the car before it drives u nuts and makes u not want to drive it. with solid mounts u will feel everything
if ur really worried about rubber/poly mounts install a engine limiting strap on the one side of the engine
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
I run solids with my 550-600hp boosted 5.3 LS. Its not even knoticable honestly. ive run poly and solid and couldnt tell the difference except when you blip the throttle. With poly the motor will rotate alittle (not as much as rubber) but with solids thats all she wrote and doesnt move at all. I ran solids bc of cheapness and my SC head unit is like 1/8" away from the lower strut tower and didn't want it to rub/hit when i'm gassin it.
Its all in the tune honestly. If the motor is tuned well and smooth then very little vibrations are felt. Big motor and lots of lope you might feel it alittle. My 521 was the same mounts and it wasnt bad at all. And my car is only driven on the street.
Personally I wont go back to poly mounts given how bullet proof the solids are (esp with heat!) with no vibrations.
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
Ok great information. I have solids in my 49 with a healthy cam and it annoys the heck out of me. I used to run solid in my 86 and a healthy cam with no real problems.. I'd just prefer soft mounted so I'm thinking poly would be the best trade-off.
Engine is out and I'm going to take the oil pan off today or tomorrow. Just curious if the rods all look straight still. Still no word on the heads but should know by tomorrow.
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
I never realized you had 2.5in cold side plumbing either. Hard to believe, but I wonder if that really was holding you back? Our setups were pretty similar, but I have 3in piping and even with my little 62mm I was 10.7s @ 130mph. Just something to think about I guess. Good luck on the new setup!
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
There are a few possibilities left:
1> The 2.5" piping
2> The 113 heads
3> The Megasquirt 2.
I've now seen several posts/videos where people have claimed getting rid of their Megasquirt made a big difference in their performance. My friend's stock TPI intake/cheap world product heads/76mm went 112 mph in the 1/8 to my 98. Nearly identical to mine in header sizing, weight, cam, converter, you name it. The biggest differences were those three things. Fast EFI, 3" intercooler piping and those heads.
The Megasquirt is staying for now. If it runs like crap still, I will be moving to a Holley EFI system and that should answer the question.
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
State of tune is state of tune. It dont really matter what the controller is to a degree. If its delivering the spark at the commanded time and air fuel is legit, then its gonna make the power it makes and thats it.
Proof is your dyno numbers are there. They indicate the car has power to run better times, so only thing that could be happening is trans/converter issue not getting power down.
If the log of the run seems to match the dyno run logs as far as what the motor sees for fuel and timing, then it should run good
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
Out of the three I will still say it was the 2.5" intake tubing holding you back.
Let's break this down Steve, you made 603 horsepower at 23-psi. For every 1-psi of boost we will realize a 6.8% increase in power over what your engine makes naturally aspirated. For every 7.5-psi of boost we will realize a 50% increase in power over what your engine makes naturally aspirated. For every 15 psi of boost we will realize a 100% increase in power over what your engine makes naturally aspirated. For every 23-psi of boost we will realize a 156% increase in power over what your engine makes naturally aspirated. This is what we get with your engine at 23-psi making 603 horsepower...;
Your engine made 236 horsepower naturally aspirated during that run, and that was with 350 cubic inches, ZZ3 heads, 224/224 cam, 114 octane and more timing thrown into the tune. This should tell you if your intake was limiting horsepower or not...
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
Boost is a measure of restriction to a degree. You cram mass into the system, it backs up and creates pressure which is measured as boost
Larger heads intake and piping just reduces pressure by passing more of that mass flow. Make same power on less measured boost pressure
You can pass the same mass flow thru 2 different sized pipes, the only thing that changes is the velocity of the stream
Larger piping may reduce some restriction there but i dont know if that will automatically mean more power. Perhaps on a small turbo deal thats near maxed out lke yours was. That would make sense to me.
I know i didnt gain much if anything when going from 3" to 4" piping to throttlebody at same boost pressures. I changed coolers and turbos at that time so i think any small power gains was from the efficiency increase
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
Remember that I am not saying the switch to 3" tubing would bring this "tremendous" power increase, however it more than likely was the culprit for some of the barriers that he hit, and it sure as hell would have made more power overall at the same boost pressure. From 2 1/2" from the turbo, to 3" orifice of the IC, back to 2 1/2" tubing leading to the throttle body is cause for concern because that is an unneeded restriction for the turbo to overcome. At any rate, I think the 3" tubing would have been easier on the turbo, and made him more competitive with that C4 he was comparing himself with at a much lower boost pressure...
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
I talked to the C4 guy today and he had 3" so that is a possibility to consider. I should have upgraded mine sooner and I was making more power than I originally intended. But that amount of power didn't translate into the mph I was expecting (100 1/8).. Hence the continual effort to increase power. Anyway, it would be nice if I can stay with the MS and make good numbers. I don't want to spend that money for the time being.
Might go out this afternoon and peak at the bottom end. Not looking forward to the dripping oil when I flip the block over though!
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
Great news on the heads! Shop said the valve seats and general sealing of the valves was perfect. Normally they find at least a couple of valves not sealing perfectly. I now have them back home to clean up the castings and then will bring them back for reassembly.
I had ordered a couple of 6" carbide bits to clean up things - one for aluminum and one for steel. My headers had weld protrusions that I had never cleaned up because I thought it would be an act of congress. Well I'm here to say it took less than 45 mins to do both headers, the crossover pipe and the merge pipe to perfection. And it was a lot worse than I realized - mainly in the collector area. It should help this new setup to get rid of all of those obstructions. Hopefully the cylinder head work goes as well.
Debating between the HSR and a Super Victor EFI. Still don't have the intake paid for as he has been busy so I still have a choice. Do you guys think a Victor is going to make torque unbearably low? I've had good results with horsepower cars because traction off the line is easier to get. I sure like the idea of going to an LS throttle body over reusing the stocker. Thoughts?
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
Torque is fine with the victor. Runners are similar to hsr in length. Air distribution with center fed elbow single plane should be better and net more power over hsr but usually thats higher rpm power
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
Originally Posted by ZZ3Astro
Debating between the HSR and a Super Victor EFI. Still don't have the intake paid for as he has been busy so I still have a choice. Do you guys think a Victor is going to make torque unbearably low? I've had good results with horsepower cars because traction off the line is easier to get. I sure like the idea of going to an LS throttle body over reusing the stocker. Thoughts?
+1 for the Super Victor EFI, although both will get the job done.
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
The heads are nearly done.. Well one is done and the other I still have some sanding to do on the other. Hoping to finish today. A new girl has been in the picture for the past couple of weeks so the entire schedule is in question. Finally found one that has gotten in my head real bad. LOL. Anyway if I can stay on the tracks, the heads will be assembled by the end of the week. My Victor EFI arrives tomorrow. Hoping next weekend I will be able to drop it in for mocking up the throttle body elbow. Then I'll have to order the next round of parts to make it all fit.
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
Originally Posted by ZZ3Astro
A new girl has been in the picture for the past couple of weeks so the entire schedule is in question. Finally found one that has gotten in my head real bad. LOL...
Don't make me bust out the this thread is worthless without pics emoji...
Re: Turbo Iroc - Round Four (Edit: Staying Gen1, new PT7675, heads, intake)
Forgot to mention I put a video up that shows how the heads turned out. I have the bottom end back together except for the heads, which did not get returned to me on Friday. Not a big deal though, it's super hot this week anyway and my friend brought his '13 SS to put a new Corsa exhaust system on.. one project at a time!
06-13-2016, 08:58 AM
