Thread: 500-600 WHP Build Questions

i forget at the moment what it takes to run stock heads and an st5 cam. just the guides needed to be milled if i recall correctly.

someone else can correct me. i wouldnt go bonkers on heads spend that money on the trans.

Originally Posted by jbunla

Jdredd, a lil of topic but did you ever do a turbocharged setup on stock heads and cam (L67/L32), your numbers are impressive just wanted to know what a baseline will be for a stock turbocharged GTP engines.

Nope never tried.

The heads I have now, still have stock valves. Not super ported like a ZZP set of heads would be.
Maybe "Stage1" level ?

Originally I took them in to just get cleaned and new valve guides is all, but guy gave me a deal on some work to clean em up.

The old cartuning car from years ago ran 11.4's on stock cam/heads... just rockers if I remember right.
I bet with a newer/bigger better turbo, probably could have gotten to 10s...

Kalo's old turbo Impala went 10.0's on stock heads (spring upgrade) and st4 zzp cam.

So can go pretty far on either stock. Don't have to go overboard to still get good results.

Originally Posted by ImNowTylerTibbets

i forget at the moment what it takes to run stock heads and an st5 cam. just the guides needed to be milled if i recall correctly.

someone else can correct me. i wouldnt go bonkers on heads spend that money on the trans.

ZZP shows " This cam can be used on stock heads (with spring/mofified retainer upgrade) "

• Duration @ .050" is 230°/224°.
• Lift is .544”/.536” with 1.6 rockers.
• Lobe separation is 117 degrees.

Originally Posted by jdredd

I bet with a newer/bigger better turbo, probably could have gotten to 10s...

What newer/bigger turbo brand(s)/model(s) would this include. Im a turbo noob so im trying get good advice.

Originally Posted by Xorbex

What newer/bigger turbo brand(s)/model(s) would this include. Im a turbo noob so im trying get good advice.

If I remember right, it used a PT-61 on center style turbo. Tangential style has pretty much take over as the exhaust side choice.
Going slightly bigger on the turbo size it self, the newer billet wheels that are being made, ball bearing for faster spool/response...

Precision GEN2 PT6266/PT6466/PT6766 CEA in a .68 AR models, depending on goals, would probably do majority of people here just fine.
All of those 3 would get you to the 600whp mark at minimum and the more with the slightly bigger sizes.

Other brands out there too that people could chime in on... Right now I am a PTE leg humper, so I don't keep up with other brands...
But no need for a street/track warrior to go super big.
The ZZP/Stattama T67 was a mutt turbo they made, but it ran very well for what it was. Been pushed over 600whp before. Had I just
been smart, and gotten a new converter, and pushed 25/26psi, I am sure I'd broke the 600whp mark with it no problem.

Originally Posted by jdredd

Precision GEN2 PT6266/PT6466/PT6766 CEA in a .68 AR models, depending on goals, would probably do majority of people here just fine.
All of those 3 would get you to the 600whp mark at minimum and the more with the slightly bigger sizes.

So basically a T4?
http://www.precisionturbo.net/Street...-CEA%C2%AE/479

Big t3 is key. Our .82 t3 turbo will flow lbs/min for 850.
it's just that our drive Delta will increase up near the limit

Originally Posted by jbunla

Thanks for the response; do you know what boost levels that was and the turbo if you will. I have tried doing searches on clubgp but that is a headache. You older forum members probably can remember instead, my buddy is trying to go turbo but will rather do straight line stuff.



Yeah I was going to say the same thing, the problem is those are getting really hard to find now a days with the proper wheel and type of housing (garrett tang style). My buddy's dad has a GN and I know for sure the turbine is a t3 with God knows what type of exhaust wheel, but I know his compressor is about t4 66mm wheel

I can't remember the boost levels anymore ... i'd say 15-18 range probably.

I am no expert on turbos.. But this was my thinking on my build when I was at it...

I had the ST5 cam.. biggest ZZP sold. (Small compared to blower cams)
I was going for track usage. Street usage not much at all.
I was going to be spinning some 6500+ RPMs due to the cam.
I had PLOGs. (Others have gotten great numbers)
I had 2.25" cross over.
I had some yocal ported heads with springs.
I was gonna use e85. (helps spool quicker)
I had a 200k mile L67 ... so lower compression but strong..

Exhaust velocity did not seem it was going to be much of a problem to get a 65mm exhaust will a spinning ( i think it was 65mm.. been awhile )
Spool was pretty damn fast and just kept going.

My car is lighter... ~3100lbs at max, without a driver. So that helps get it moving.
Once I started to get the 60 foots decent, I could hit high 10s at 15psi.

With the ST5 cam, it was recommended to rev it out pretty high. If I had ran 150# springs instead of #130# , results might have been a few ticks better before converter slip killed me.

With turbos so much better compared to 12+ years ago when people start to finally slap turbos on and see what happened. Lot of guys used pretty small T3's and couldnt break 400whp.

The T67 did 529whp @ 17psi like it was nothing. And this was with mostly going by paper, and then slapping it all together and see what happens as my first turbo anything.

Had I been smart, and kept eye on TCC slip, I would have realized how much power was getting lost.. Once above 17/18psi, TCC slip was out of control at over 1000 slip over 20psi.
Guys at ZZP were surprised I ran as well as I did at the track.

So I guess with that, my feelings are, go T4 its a bit bigger than A T3 .. but not monster... but the 3800 will be fine with it.
Go with a good turbo line that is not known to be lazy spool.

Also from what I've been told by the techs at Precision, I was told their HP Number ratings, are for the highest AR sizes. And that smaller AR the max HP goes down. But they didn't give any good rule of thumb of that that may/could be.

Also remember, 20psi from one turbo setup does not equal the same as 20psi from another turbo setup. So always keep that in mind. As A similar setups to what I had, but with the cartuning kit and say 2.5" downpipe, put down like
505whp but I think he was at 22psi.

GREAT Info from Judge Dredd himself

Originally Posted by 518GTP

I run a precision 6466 , ZZP s3 heads , st3 cam , e85 , 1000cc injectors. I look for more of what the car runs than what it makes. But my setup got me 10.9@128 with a 2.5" downpipe on 22psi

what 60' time?

only a 1.76 sadly :/ , I think with a 1.65-1.60 it would go 10.60s

Originally Posted by SgtMarshal

T4 is the size of the turbo inlet, or something like that. you will need a T4 for what you are doing, a T3 will spool up faster, but probably wont have enough flow to hit 600 hp. that turbo you linked should be good, just need to make sure it will bolt up to the kit you have, not all turbos will bolt to every kit because they are different.

t3 t4 t5 t6 refers to the frame size of the turbine housing. all can be had in a multitude of a/r sizes. for a 3800 like many others have said...if you are goiing with a t3 a/r needs to be up around .8 or .9. if you go with a t4 frame a/r should be around .6 to .7. t5 and t6 are way to big for any 3800. when someone is talking about the a/r of their turbo they are talking about the turbine side as it is the only number of any real consequence when talking about a/r sizes. a/r on the compressor side is fairly insignficant.

almost all compressor covers widely used today on t3 and t4 turbos are of the t04 variety.
t04e refers to a compressor cover with a 3 inch inlet/2 inch outlet with a .60a/r.
t04s refers to a compressor cover with a 4 inch inlet/2.5 inch outlet with a .70a/r
t04h refers to a compressor cover with a 4 inch inlet/3 inch outlet with a .75a/r

the trim number of a turbo is basically useless information if you dont know either the inducer or exducer size because it only tells you the pitch rate of the fins on either the compressor or turbine wheel. none of the turbo manufactures seem to be willing to give you all the information you need which sucks. precision for example will tell you the exducer size of the turbine and the inducer size of the compressor but not the side of the corresponding inducers and exducers or the trim on the wheels so without physically measuring them you cant calculate the others. for most people it doesnt really matter but would still be good informaiton to have. garrett has assigned letter values to their trims for some reason or another p, q, o etc. i have yet to see a document that states exactly what those letters corrolate too. so the newer ish precision CEA 6466 has a compressor with an inducer of 64mm and a turbine with a 66mm exducer and utilizes the CEA billet wheels. an older PT series turbo say the 6152e (what came with the cartuning turbo kit) has a compressor with a 61mm inducer and a 52trim on the turbine with a t04e compressor cover. all of these wheels can be trimmed to fit into various style exhaust housings....unfortunately knowing only a portion of the information is useless and makes it pretty hard to understand what exactly you are getting.

compressors can support a wide variety of power depending on what turbine wheel they are coupled too. going back to the PT series of precision turbos. the 6152e what came with the cartuning kit is rated at 630CHP however that same compressor coupled to a 76trim turbine so a 6176e is rated to support 690CHP. when it comes to turbo lag, efficiency, its 95% about the turbine side.

if you were looking to collet all the infomation for a partucular turbo you would need:

inducer/exducer turbine wheel
calculate trim rate
turbine housing style
turbine housing a/r ratio
inducer/exducer compressor wheel
compressor housing model
calculate trim rate on compressor wheel

thats all the important **** anyway...

I am by no means an expert but this is what i have noticed in my time playing with turbos. hopefully there isnt any misinformaiton in there. im sure someone will correct me if i am wrong.

.82 t3 is where it's at.
The only way to get it is with one of the old Garrett housings or one of the new AGP castings... they ain't cheap.