DIGGLER

iTrader: (1)

Yea there is actually an article hot rod did on his engine after it let go. He had made several passes emptying the radiator, and when he pulled the heads found a crack in one or 2 bores. Block was not filled, and he was pulling timing and backing off on the boost down track to keep the head gaskets in it.

Orr89RocZ

iTrader: (20)

Ahh that makes sense. Same thing my buddy did around those times as well with a 6.0
Block

ZZ3Astro

My current 6766 is a .96 ar but in theory I can probably talk them into swapping the housing when I send it in for rebuilding. I definitely plan on a brake this go-round. A little bit of softness at the start isn't always a bad thing anyway though.. keeps the wheels from spinning as easily!

ZZ3Astro

One last blast from the TPI/PT6766. I was still conservative with the tune because I want to preserve this engine for the 49. I put in 60% 114 octane with 93 octane for an estimated 105 octan, pulled the boost limiter program and added about 4-5 degrees of timing in the 140+ kpa table.

Results: 603/621 @ 23 psi




I think it still has another 20-40 available at 23 psi as I only put in the initial timing and for the 603 run added 1 degree at peak rpm/kpa. Also more boost if I had a 3 bar map. In other words I never explored the limits at all. Pleased to see some real numbers out of this old setup. I'm also nearly maxing out the injectors.


Some of you may recognize the dyno as the punishing Mustang dyno that I did the first stock tpi/turbo dyno video from where it only offered me 270 rwhp. 5.3 project is absolutely on the go - just wanted to hear the 6766 one more time before this engine comes out.

DIGGLER

iTrader: (1)

killer! it sounds fantastic and really is still pretty dang good for what it is. (stockish zz/tpi intake/700r4)

vortec350s10

Awesome Steve! Thanks for sharing. I hope to someday see numbers closer to those. I have been trying to keep track of what you have going on, but I have a few questions that I could probably find answers to if I did some digging. But hopefully you can refresh my memory! Is this a ZZ4 long block? I believe they had a forged crank and hyper pistons, can you list the setup one more time? Block, crank, rods, pistons, cam, heads, etc. and is this still Dana's 700r4 setup? I'm also curious what kind of timing you are running on top end. I know you have to keep it backed off quite a bit in the midrange where the torque is massive to keep it out of detonation. Glad to see it live another day!

ZZ3Astro

It's a ZZ3 longblock with the following changes:


SRP forged pistons
224/224 hyd roller cam & matching springs
Cometic head gaskets
ARP head bolts
ARP main bearing bolts
SFI flexplate
Extremely mild pocket porting on the ZZ3/L98 heads
Compression works out to 8.6:1


The stock PM rods are the weak link in this setup but it only turns 5300.


Yep 700r4 is still holding together on the dana kit. It does slip shift into third and when it was apart a year or so back it was showing wear on the third gear clutches but everything else looked great.


Timing at 4900 rpm looks like this on the 93 tune:


155 kpa 37.2 deg
180 kpa 33.9 deg
205 kpa 30.9 deg
230 kpa 27.3 deg
255 kpa 23.4 deg


The 3700 rpm range in boost is low 20's. Mid teens for 3100 range.


The timing at 4900 for the 105 (race gas mix) tune:


155 kpa 41.2 deg
180 kpa 37.6 deg
205 kpa 33.9 deg
230 kpa 30.0 deg
255 kpa 25.4 deg


Definitely could have added more timing but not sure how much more it would have made. Duty cycle on the 603 hp run peaked at 97.3%!

project89

iTrader: (1)

i would still love to see that setup with a different intake , even if u just borrowed one from somone to make a single trip to the dyno.

if i didnt sell off the spare hsr's i had i would send one to u just for u to try and take it to the dyno with

ZZ3Astro

No doubt it would make some good power.. enough to fold up one of those PM rods I'd guess.. but any more power and I need bigger injectors, which will then find the limit of the fuel system once again. In the 49 though I'm going to have to run the fuel lines completely new and I'm expecting to go HSR so the intake matches the look of the air/water intercoolers... eventually I mean, not immediately. Point is between a bigger cam and that intake and twin 57's I'm sure the 49 could one day lay down more power than the Iroc did. I don't expect to keep it there normally though. 500 to the wheels is more than enough and you can die in that car much easier than the iroc if you crash.

project89

iTrader: (1)

whats that car weigh compared to the iroc?

zz17iroc

iTrader: (4)

The Iroc sounds really good at full boost, I can listen to that all day.

ZZ3Astro

Project89 I've been told all kinds of numbers but I believe it's in the 3250 lb range. Maybe even a bit lighter than that as the old straight six was heavier than a sbc. There isn't much gusseting anywhere and when you slam the doors, the post in front of the rear side window moves. What metal is there is thicker than modern but there is really very little layering anywhere. So I'm thinking about 200-250 lbs lighter than the Iroc is.

vortec350s10

Thanks for the review of your setup and listing the timing. Gives me a good idea of your timing map. I can't believe you run the timing that high under boost! Seems higher than typical N/A timing under 180kpa. Your compression is a little lower than mine, plus with the aluminum heads it must help a little more to lower the detonation threshold but I'm still surprised you run that much. Have you played around with the timing enough to know that's what it likes? I'm only running a max of 26 degrees at 180 kpa (most boost I've ran yet) on 91 with a little water injection on top. Haven't tried much more than that. I have the same rods as you so that makes me feel a little better, even though I may have a weaker link with all the cast crap spinning in my block!

ZZ3Astro

I forgot to consider one thing.. my Megasquirt has an exponential timing error as rpm increases. It works out to about 3 degrees at 5000 if I recall correctly. Timing at 3000 is very close to accurate and that is the only place I've ever touched detonation during tuning. No idea how much more it would take at 5000 but I'm proud of my reputation for not crossing the detonation threshold of destruction in this car. Can't say as much about my first boosted engine back in the carbureted days though! I was so excited to get the 144 on that I totally bypassed limiting total timing. I was just too anxious to feel the boost. It was an awesome ride for about 20 mins lol. That's how I ended up with a 383 8-71 in my old third gen and I have forever been addicted to torque since then.

ZZ3Astro

There is an LS3 in my garage right now... but not mine! Help a friend pull his '13 engine after twin 56mm turbos contributed to an apparent ring land failure. Getting some hands on LS experience though. Lot of damn sensors and oddities compared to gen1. We are pulling from top.

ZZ3Astro

The results of pulling my friends LS3...

ZZ3Astro

Not the 5.3 update you've all been waiting for but two steps closer. I drove the Iroc to a Camaro cruise in yesterday about 45 mins away. Car ran flawless but at times left a blue haze from the oil seal. On the way home I realized it has yet again taken out a plug wire. Really looking forward to the short plug wires of the 5.3 and the twin setup. Things are just too tight with a stock K member and crossover tubing on this engine. Definitely not fixing the wire again so this is the last long ride the car will make before the engine comes out.


On the same note, I just figured up my final tax payment (I'm self employed) and I paid in too much this year. Without getting into the boring details, it turns out I am now sitting on the cash to pour the slab in the shop! There is a separate thing going on with my (not very good) payroll accountant where she has made some kind of mistake. If she is wrong (as my numbers are showing), I will also have enough to do the walls and doors.


Projects should get into gear by spring for sure!

DIGGLER

iTrader: (1)

nice! i need a shop so bad its unreal. i've considered doing one like you are... have the skeleton erected and finish it up myself. but i worry it will never get done knowing me, and it might be a better idea to just go ahead and have it completed and make the payments on the thing.

ZZ3Astro

Bam! Walls next.


Slight change in direction on the Iroc possibly. Thinking about building a 6.0 block from the get-go and doing a forged bottom end. Have to spend for the shop lighting and lift first but getting close to launching this LS project.

sailtexas186548

iTrader: (2)

looking good, once you have shop space and good tooling the projects seem like the easy part!

ZZ3Astro

I've been doing some thinking on the Iroc and 49 projects and came to the realization that stealing the TPI from the Iroc for the 49 means the Iroc gets parked for a long time. Instead I'm going to do the 49 project first while leaving the Iroc running. The 6766 gets rebuilt and back on the Iroc before anything else happens. At some point I'll break the 9 bolt and at that time I'll go ahead and upgrade to a 9 inch. I can be doing various upgrades along the way so the car will be closer to ready for the 6.0 swap but it will stay running the whole time. I'll do the K-member at the time of the swap. With the 6766 already fixed by then, I'll only need to pick up a second one to have a setup capable of 1200 hp.


Meanwhile the 49 is getting major surgery: Mustang II front end, air ride, disc brakes, power brake booster, fuel system, etc. I've got my hands on a 5.3 this week so I'm going to change the cam, gap the rings, stud it, the usual. I'll put the twin 57's on it and sell the STR manifolds to cover the 5.3 costs. The 49 project begins as soon as I have a working lift and walls on the shop.


Shop progress.. pipes and conduit between the shop and house are now in place. Next is the power conduit from the trailer's 200 amp service. I was supposed to be getting a "free" 8000 lb two post lift, but the guy flaked out when it was time to meet up. I called him several times since then with no answer. My friend knows him and set up the deal. I told my friend thanks but I'm not going to chase someone around who is flaking. He said he'll deal with the guy so we'll see what happens now.

ZZ3Astro

And the lift worked out! It's a Globe 9000 lb floor clear, assemetrical and looks in good shape except I'm going to have new hydraulic lines made for it. Now if I could just get the walls up I can get the lift going.

ZZ3Astro

Not my car but on the same subject.. I had my first tuning experience on an LS engine today. My friend has a Chinese gt45 on a stock 5.3 and a Megasquirt 1. They had no real idea how to tune it so I was brought in to get a baseline tune with a goal of 650 rwhp. After years of carefully tweaking on my tpi/67mm setup to finally reach 600 rwhp, it sure felt weird to beat it with a stock 250k motor on the third pull without even trying!


Jeez the LS turbo projects are showing up left and right around here. Two 6.0 twin turbo projects under way at the shop we dynoed at.

ZZ3Astro

So that Blazer no longer has a running engine. He decided to take it for a spin the day after the video instead of addressing the fueling system issues, ignition issues and bad map sensor on the MSD. BOOM. Total engine loss + a fire. Thankfully he had an extinguisher and saved the truck but the engine ate up EVERYTHING except the intake and valve springs.


The lesson here for me was that there are Gen3 and Gen4 5.3's. The one I am supposed to be getting from my renter is a Gen3. After seeing this destruction I have zero interest in a 5.3 build - at least a Gen3. I had been planning to stick the one I'm getting into the Iroc to work out the bugs while building a 6.0 or LSX block. I'm not interested in dumping money into the 5.3 for rods/pistons. And I don't want to go through all the trouble just to have 500 rwhp and a motor that could grenade at any second. So it looks like the Iroc will be down once I pull the TPI until I can get the forged LS build going and completed.


Meanwhile I traded off the Globe lift towards a brand new Rotary 10k lb lift. The Globe needed a couple of parts and there was a delay in getting them. We needed the lift to get my friend's LS3 525 into his Camaro. He offered up some funds towards the lift and it became the only logical thing to do. A couple of days later we had his car up on the lift preparing for a bottom install of the LS3.




Next up I'm going to learn HP Tuners and work on his LS3 tune. I'm still trying to decide on three options for the Iroc:


Stock ECM with HP Tuners
Holley Dominator (maybe HP instead not sure)
Megasquirt 3 Gold LS

customblackbird

iTrader: (15)

I don't understand how you can blame a gen3 5.3 for the blatant disregard for a poor setup and user error? There is no significant difference between the gen 3 and gen 4 that would hinder its ability to make a fire or go kaboom!

A couple of things...

Fuel issue? = possible fire. Over pressure or fuel leakage or could be a million things. Get raw fuel on a header and theirs your fire. That has nothing to go with the gen 3 vs gen 4 motor.

Chinese GT45? = possible fire. Questionable quality, blows up and puts oil all over the engine bay and headers and theirs ur fire.

MSD box? = possible engine failure as most of MSDs new stuff is crap. If it's the LS control box it could have crapped out and screwed up timing big time causing engine failure which could have destroyed the turbo and or caused the fire.

Malfunctioning or non working MAP sensor... Ha that's pretty self explanatory.

Judging by what you said the guys an idiot and deserved it. No one should ever take a car out or anything mechanical when it's not working correctly... That's beggin for a disaster. Esp when your dealing with fueling issues and boost and engine tuning sensors. My only gripe besides the poor motor that went up in flames is that the operator was so lucky. Not only did he risk his own life but others as well.

The basic geometry of the gen3 and 4 motors is mostly the same. Besides some rod changes and intake ports etc. not huge differences and the motor still runs on gas... So always the potential for fire, even a leak at a fitting or failed gasket.

Moving on. I'm in the same boat, going stock PCM and gen3 5.3 with HPT pro. Can't beat stock with quality and reliability as well as many fail safes. I have issues with MSD and mega squirt is too unreliable in my opinion.

Gen3s have been known to go way above 500rwhp and survive in stock configuration. Most of it has to do with the tune and the engine rpm, keep it low and they will be fine. Want to spin higher then replace the rods or put better rod bolts.

ZZ3Astro

Lot of factors, true.. but I'm seeing more than just this situation. Another local guy has been through several sets of 5.3 rods (he takes it apart after races). He finally moved on to a 6.0 setup - not sure about internals stock vs forged on his. I see no shortage of 5.3's blowing up on Denmah's channel. I'm just not into blowing up engines.


The fire was from the oil exiting from all of the holes in the bottom end and oil pan. I've never seen such total destruction on an engine in person. Yes he should have left it parked. A little detonation goes a long ways towards rod destruction but I'm not sure how much that played in here. It all depends on what the broken MAP was doing as boost went up.

Jay_rich

iTrader: (4)

Pretty hard to put the blame at the Gen 3 5.3L. Going to a 6.0L doesn't change anything. Its the exact same crank/rods. The only reason you are seeing more blown up 5.3L's is because they are MUCH cheaper. people dont give away 6.0L's like they used to. My old one was 500 bucks for a longblock with the harness. Id be lucky to find one now 8 years later for under $1000

Most of Denmah's projects get blown up from either pushing them way past the limit or from reusing every nut and bolt. If you watch all of his videos one of the 5.3L's he had making 600+ had a two different heads on the thing.

I would put more blame to tuning than anything, especially with MS1. Also how happy is that dyno. No way that GT45 will make that kind of power. I have one...I dont ever see that happening.

Jay

ZZ3Astro

I wasn't so much saying 6.0 was stronger as I was saying I don't want to put money into a 5.3. If I'm going to buy forged slugs I want the cubes and larger valve capability of a 6.0. Bouncing back and forth on a stock 6.0 block vs LSX block. I like reliable horsepower but don't want to spend a lot of money where it isn't needed. Still think LSX iron is the best way to go for my plans.

That dyno is within 3-4% of other dynos in the area (to the high side). At 600 that is 24hp high. Pulsewidth supported more power than the truck was making as well. But dyno numbers are subjective anyway. He is putting the truck back together with a gen4 5.3 and fixing the various issues. Then it will go to the track after further tuning. MPH will tell the story.

Speaking of MSD - I didn't realize they had gone to crap. I do know the tuning software for that box was very poorly designed. Hard to wrap your head around that (ill)logic.

customblackbird

iTrader: (15)

Yup, the new MSD stuff is garbage for the most part. Stuff is made in China for a large percentage of their products. Their old analog stuff is tried and true, once they went digital so did the quality and reliability. What sucks even more is they bough Mallory... Which was my go to company for things ignition. They bought them out and still continued to make crap products. So who do we go to now? Crane, pertronix, fast, accel or the new summit boxes etc. I've had crap go wrong with accel and fast and pertronix don't have enough products out. MSD is cornering the market and providing crap... I guess we're all screwed at this point.

DIGGLER

iTrader: (1)

i would probably get started with a factory 6.0 block and spend the money saved on the lsx block on other things. you can make around 1200 at the wheels fairly reliably with the stock block, and at that hp level you will spend all your time trying to make the chassis work.

Jay_rich

iTrader: (4)

Honestly if you want the cubes, stick with the standard Gen3 or 4 6.0L, forge it and be done. Gen1 LSX blocks (aftermarket ones) are week, Gen2 LSx blocks get pretty pricey. There are way too many 1000+whp Stock block guys for me to ever consider spending the money on a dart/LSX/RHS etc. Especially for a street car.

Jay

project89

iTrader: (1)

brand new iron 4.8/5.3 block $299

http://www.summitracing.com/parts/sum-4853l/overview/

hell im thinking about buying one for myself just cause a friggen ls anything in my area out of the junkyard starts at 2k ( want an ls1/t56 combo out of the boneyard it will be 3500+ easy and more then likley over 4k)
i could buy that block and the rest of the parts i need online to assemble it much much cheaper

ZZ3Astro

I guess I can use this 90k mile gen3 5.3 for mocking up everything and then sell it to cover some tires later. It already has an LS6 camshaft so I'm sure someone locally will grab it up quickly when the time comes.


Sitting here waiting on the contractors to show up to finish my building. The building contractor keeps pushing the start time back to complete my walls (gables) and hang doors. My electricians really ticked me off by promising Thursday (they knew we needed power for the lift - thankfully I temp powered it Monday). We were supposed to have outlets, lift power and LED lighting by Friday. Not a word not a sign of them. Very frustrated at the continual cluster it has been getting good (or any) work done around here. I end up doing everything myself when I have a business I need to be running/working in. But to build gables on top of 12 foot walls requires some kind of platform or lift that I don't have. That means big money to rent.


So ready to start the car projects!

86CamaroDan

I second that. Two MSD boxes and a MSD stand alone distributor in 6 years. Switched to HEI8 and never looked back.

ZZ3Astro

Just a few updates..


Shop is complete! Still need to finish up the 110v wiring, get an air compressor and water completed but otherwise is functional!


Iroc - Still no change in the status. Business is becoming less certain for summer and beyond so I have been focusing on paying off debt related to the shop. Car projects are somewhat on delay and re-assessment. I did the math on the Iroc and I need to spend $16k just to prep the chassis for 1000+ hp. That was an eye opener and I'm trying to decide if it is worth that to me. I have some other ideas that would leave the Iroc untouched, starting with putting the 5.3 in the 49 for now. I've even entertained the idea of selling it again.


Speaking of 5.3, my friend that blew up the blazer I was helping tune is back. They put a gen4 5.3, alum block(!!), ported heads, bigger cam and he bought my On3 7875 that the Iroc couldn't spool. I tuned it yesterday to run and drive (dyno tuning next week). We drove it around the block and the airflow is unbelievable compared to the zz3. It instantly spools that 78 like my zz3 spools the 67... and it's not even tuned yet. It has no timing and was 10.2:1 afr. Speaks volumes about how restricted the airflow is in the iroc engine.

Drac0nic

Have you looked into the LSA rods? That's the way I wanna go for a budget build, way beefier than gen4 rods even and they are about $330ish. Blowing stuff up is kind of the way things work if you're trying to do more with less. Fast cheap reliable pick 2 as they say.

$16K is a ton of coin, and quite frankly I think going full race with the IROC is against what you originally intended with the car. I realize that thoughts evolve but even so.

In terms of a ZZ3 vs a heads/cam 5.3L it's apples and oranges. The ZZ needs a non-TPI intake to even have a chance, and that's not even accounting for a set of stock heads compared to ported much less their generational differences. Low timing is a characteristic of the engine and its combustion efficiency, which is caused by a lot of factors that may or may not produce power. Not saying it isn't a better engine overall (look at how many stock, mildly worked parts are on it for the power) but rather saying your SBC is trying to compete with a hand tied behind its back.

Jay_rich

iTrader: (4)

Shop looks great!

Where is this 16k value coming from? Is the Iroc pretty well completely stock suspension wise? if so I guess I could see it adding up. But really you dont need that much to support 1000hp which a stock 5.3 isnt going to last long at. I would say I'm like maybe 5k into suspension/rear end on my car. Stock form the do pretty well.

Jay

customblackbird

iTrader: (15)

Agree with above. 16k in suspension? lol geez.

If you spend 5k on suspension thats pretty standard. Thats including everything tubular, kmember etc, high end shocks/struts and springs etc. and even a roll bar/10pt cage.

Only way I see you spending 16k is if your back halfing the car, tubing it etc.

1000hp on a stock 5.3 is doable, and could last while with small upgrades. Pistons and rods/rod bolts. Push +20psi through a stock 5.3 and it will make 1000hp. Head studs and call it a day. I'm at about 600 on a stock 5.3 with 10psi ish.

ZZ3Astro

Not for a 5.3 but for a LSX 6.0+ build with twin 67's, and not just for suspension but all supporting mods. I've added it up 100x and it comes to 16k minimum. Doing it right of course - coil overs over up front, k member, brake upgrades, 9 inch, 4L80 build and converter, fuel system upgrades, 4" exhaust system, wheels and tires to fit new brakes + lighter weight than stock, aftermarket ECM. That doesn't even get into the little things that add up like gauges, liquids, etc. Also it doesn't get into any safety equipment. Do the math, it's 16k before building the engine. Actually a decent ECM like a Holley HP or dominator will bring it north of 16k.


Now if I went with a 5.3 or reconfigured my gen 1 and aimed for 700-800hp, I'll still need most of the upgrades. I could do without the k-member but that's just more weight to fight and less access to working on things. Fuel system is guaranteed to hit a wall as it has time and time again as I raise power, though boost would be lower so it might not be taxed as much. Transmission? Forget about it. I'm already beyond the hp I built it for. Same with the 9 bolt - it's one drag radial track launch away from a $3000 replacement cost. I can save a thousand here or there but have less of a car at the end of the day. I don't want to spend any money on this car if I'm not going to do it right this time around.


Draconic - everything definitely changed with this car. The original project is well in the past. I won't call it fail by any means but it was an incredibly difficult project because of arbitrary rules I set in place to keep the car somewhat factory-plus. It fought me every step of the way but I did exceed my original hp goal by a good bit. That engine is probably a ticking time bomb with that torque through those rods!

customblackbird

iTrader: (15)

Sure when you think about it that way. But why do u need all that? Why does anyone need a 6.0 and twin turbos pushing 1000hp? U can't use that power 99% of the time. 600hp on the street is too much for most people and easy enough to kill yourself. Why not have 600-700hp on the street and drive it fast and enjoy it without having to worry about pushing everything to the limits.

Run a tubular Kmember for room, $250 for a 4" exhaust from the headers back. Run the stock ECM and tune it or throw a MS3 for cheap aftermarket. Turbo a stock 5.3 and upgrade the rod bolts if your that worried and throw a 340 or 450 in the stock tank with a new -6 feed line and call it a day. Your rear could be replaced, ford 8.8 or strange 60.... I wouldn't touch a 9" over the S60 and if your overpowering a ford 8.8 then go S60. SFC and tubular suspension components are cheap when you think about it. Trans is a different story but you can make a 700 or 200 live to 800hp pretty easy/reliably if your going auto. The OD will increase the cars ability to drive on the street and get respectable MPG. I'm sure you have a different way of thinking what's "right" but theirs 2 ways to skin a cat and both ways you can do 700hp but be about half the cost.

If you go stock ECM and 700 trans you can get the stock gauges to work (my experience with firebirds tho).

I love to see cars with tons of money thrown at them and making stupid power but 1000hp is worthless if it doesn't get to the ground. Give me 500-600hp for the street and make it reliable.

But it's your decision and your car so it's up to u.

ZZ3Astro

Once the 49 is done (whether tpi from Iroc or do the 5.3) I will already have two 600 hp cars and have no need for a third "only" 600 hp car at that point. The plan with the Iroc was to go to the next level and be high 8 low 9 second capable. More of a race car than a street car. And definitely 900+ hp like my hero Orr!


I have considered 8.8 and S60. I didn't see a huge advantage cost-wise over a 9" once you hang the other goodies on it like limited slip. Maybe a few hundred. 700R4 definitely not an option for me. I'm not doing all of this to worry about breaking anything every time I go to the track. Been there, done that too many times. I've been very fortunate with the current 700 though!


I have a new project in mind (AWD 5.3 setup) that will cost less to build than supporting mods on the Iroc (less even if I put a few of the less needed mods on the chopping block). It's a special project that I won't document on youtube until after it makes a few rounds at the tracks. One problem I had with the Iroc was many people at the area tracks were aware of each change I made and would come up and mention my latest video, already knowing what I expected it to run.


So it is possible that I just leave the Iroc as it is. Possibly throw a 8.8 in it when the 9 bolt breaks and just slowly upgrade things like brakes. But the question is, how many cars are too many cars? LOL.. I'm already having a tough time deciding which car to take to dinner and I'm going insurance poor (though the Iroc and 49 are very cheap to insure.)

customblackbird

iTrader: (15)

Ok gotcha. Just hate to see a project go unfinished or ditched to people over shooting costs/purpose. AWD would be intersting tho.

9" is not even close to the strength of a S60, and the S60 eats less power. IMO

Too many cars?! waaaaat lol. I get the insurance aspect tho. 1 car, 1 truck and a bike for me. Dads got 2 vettes, a DD and a truck. My brother has a vette and a truck. Insurance can be a PITA tho, firebird gets classic insurance to save the cash.

ZZ3Astro

I'm insurance poor right now. I'm spending almost $14k a year between business liability, my boat and the vehicles. That doesn't include forced medical insurance and I can't even get homeowners right now (need roof they say). The GT-R makes up $3600 of that which is why I'm starting to consider building something AWD. I do like it a lot though. I'm always looking at ways to reduce the bleeding of my cash though.

ZZ3Astro

Ok so I have done a few things on the Iroc's behalf and have somewhat updated the short term plans:


1> Sent the PT6766 back to Precision for a rebuild (FINALLY)
2> installed the original ebay T70 back on the Iroc temporarily
3> bought new hood struts (this is progress!)


Having not driven the Iroc for months, I have to say I really enjoyed the experience. It's difficult coming from an "on the rails" GT-R to a worn suspension Iroc with ET Streets on it. I need to be extra careful not to forget that I'm not in the GT-R.


Money permitting, for the next few months the Iroc will stick around. Long term if I need to offload some things to shore up my financial plans then it would be first on the chopping block. I'm going to degree the cam in the very short term - like as soon as I'm bored enough to start the process. If it is advanced then I will retard it 4 degrees. If it is not advanced, I'm going to consider just putting a bigger cam in place, mainly a split duration favoring exhaust. Option B is 1.6 rockers. If it's still around when I break the rear I will do the cheapest option (8.8, S60, 9"). If it's still around when I have the motivation and funding, I will do the cheapest brake upgrade I can that actually makes it stop and fits within the stock 16" wheels.


With the T70 (61mm) it just spins the ET's like you're on wet roads. Once you get traction it noses over in the higher RPM but overall runs better than a lot of cars. Once the 6766 comes back, I'm going to take it to the dragstrip which is finally reopening this month after a year. Hoping to make the GT-R vs Iroc race a reality.


Long term who knows.. it might be sold or end up with the LS option.

DIGGLER

iTrader: (1)

a quick brake upgrade would be to get your rotors turned and put some agressive pads on there. Like autocross type stuff. You will be suprised how crazy those things work. Wont be the best for an open road course, but you dont do that anyway.

ZZ3Astro

I have Green Stuff pads already.. it was an improvement. Color me spoiled though, my GT-R front rotors at 15.35" diameter are basically the size of the Iroc wheels. Of course without ABS I don't have to go giant... I'd just like to feel like I have more than enough braking force available instead of too little.


Finally brought the Iroc up on the lift tonight and quickly stripped down the front of the engine. With the timing cover off I can see the timing chain is showing no signs of wear and verified it is on the 0° position. I have a piston stop ordered so as soon as I get it in hand I will work on degreeing the cam to confirm it wasn't ground incorrectly (I have the cam card on hand). I do know I ordered a factory roller cam and they sent a retrofit roller, so it is entirely possible there is a difference in the cut from what it should be. It was worth a shot at least. If it all matches up I'll just have to decide then what to do.

ZZ3Astro

Precision called. The turbo is trashed and cannot be repaired. They are offering me a very good price on a new one.. ball bearing price is even a better deal at only $300 more. I haven't asked yet but they seemed like changing to a different turbo might be an option. I've had a 76 PT on there before with no joy but that's exactly what my friend ran on his TPI with great results (different heads). I'm in the middle of degreeing the cam now so if I find that it was not correct then I'm going to look into upgrading to a bit larger platform.. choices are (billet wheel like mine)


7175
7275
7675


These three all have a 3" outlet. My intercooler is already 3" so I'd probably just upgrade all intercooler piping to the throttle body to 3". All boils down to whether or not I can get this engine to spool the bigger turbo. Out of three 72 to 76mm turbos, it has never been able to spool them up above 13 psi or perform like the 67mm does.

ZZ3Astro

Ok I confirmed the cam timing is correct. I also found that the balancer mark is 4 degrees retarded which means my base timing is wrong by the same amount and my overall timing is also in error. I have tuned to the point of detonation and backed off, and I already have an exponential timing error on the Megasquirt, so I don't think I'm leaving much on the table even with the incorrect information.


This means the problem most likely lies in the overall flow of the intake/heads, and/or the cam just sucks. I was already putting the high dollar LS Iroc project on hold and was going to proceed with the 49 project (5.3, air ride, brakes, IFS). Well now I had an employee leave and that has temporarily cut into my play fund even further. That would be an 8-10k project. Now I'm looking at ways to hold off on that but still entertain myself with some wrenching. Here is what I'm thinking of doing:


1> Ask Precision if they will upgrade me to a 7675 CEA. It should be around $100 extra. If they will do that:
2> New cam, split pattern to help exhaust, 112 lobe sep, somewhere in the 228/236 range with similar lift to my current cam.
3> HSR intake (both for flow and because the TPI has to come off for the cam swap and I don't want to deal with it any more - pain in the rear!). Also I can sell that polished intake and recoup a lot of the HSR cost.
4> Upgrade to 3" intercooler piping across the board (76 turbo has 3" outlet)


This would leave me at a total cost of less than $2000 minus whatever I sell the polished tpi for. Probably sell the cam too. It's certain to improve the numbers for the Iroc. Meanwhile the 49 will get a few things done but not the whole build until the Iroc is done. This buys me some time to restock my accounts for that project. Any less torque, more top end power might save the 9 bolt from dying as quickly.


So assuming precision plays nice, the Iroc's version 3 will be gen 1 after all.

ZZ3Astro

Well the answer was yes and no. They were going to reuse my housing and that was saving money. But they had also been talking about how my setup seemed to be making a ton of heat (based on the damage) and felt it really needed a bigger turbo anyway. I explained I had tried several 76's without luck but I'm making some changes and would rather have a 76 for future use anyway. They twisted my arm with a great price on a turbo I didn't know about...


GEN2 PT7675 CEA... ball bearing and supports 1300 hp (about 1000 on a V8). So now I'll be forced to make whatever changes the car needs to spool it, although the ball bearing will help on that!

DIGGLER

iTrader: (1)

hsr, new cam, and a 76 should pick up huge.