Turbo Advice for Series 2 3800

[SlowFiero]

I am looking for some advice on the hotside for a custom turbo setup on my car. It is a series 2 3800 installed in a Fiero. I cannot decide if it would be better to run the Buick 3 bolt housing with an external gate, or run a T3 housing or even a T4 housing. What would be best for spool, while still giving me room for 450-500 RWHP? I will be going with a 6262 for the turbo as I believe from what is being done with your cars, it will be capable of reaching my goals. The car will stall to ~2500 rpm on the foot brake, but I have a Bailey 2 step installed to get full throttle airflow through the engine. I am going to try the timing cut as well and see if I can get some more RPM out of the convertor.

Thanks for your time and advice.

 

[kshef]

I'd go with a T3(or T4 if you have bigger plans), especially if you aren't keeping the internal wastegate...gives you more options and room to grow

I ran 112mph in the 1/4 in my 4080lb. park ave with a non-intercooled 50mm T3...stock heads, cam and manifolds. probably gonna go to 6076 or 6176

 

[SlowFiero]

T3 over t4, will it spool quicker with the t3? What size is the T3 4 bolt exit flange? Is the t3 4 bolt considered a tang. housing? I guess the v band housing is 3" so I assume similar for the 4 bolt outlet.

I was thinking the Buick housing because I kind of know what to expect for spool with it. RJC makes block off flange that will do up to 3.5" downpipe.

I suppose a straight t3 will give a bit more for options though.

I am changing from a mid 11 second 3050 lb supercharged setup, and would like to still be able to get 1.5x 60 foot times, but with more topend.

Thanks

 

[kshef]

T3 over t4, will it spool quicker with the t3? What size is the T3 4 bolt exit flange? Is the t3 4 bolt considered a tang. housing? I guess the v band housing is 3" so I assume similar for the 4 bolt outlet.

are you fabricating the turbo piping or is it a "kit"?
a 6265, T3 v-band .63 would be nice

I am changing from a mid 11 second 3050 lb supercharged setup, and would like to still be able to get 1.5x 60 foot times, but with more topend.
Thanks

I never had "top end" with the supercharger...when you switch to turbo, hang on tight

 

[SlowFiero]

I am fabricating the piping. I thought a 6265 would spool slower, and with my current converter, that is my main concern. I am sure there will be a huge difference. Is a t3 v band 3" outlet?

Thanks for your input

 

[kshef]

what converter? you have heads and cam?

T3 v-band is 2.5"
T4 v-band is 3"

 

[SlowFiero]

Neil Chance custom converter. Stalls to 2500 on the foot brake and flashes to ~4200-4300 on launch. That was with m90 making 365 corrected hp.

I will have a cam, either a 212/212 or if I can't find that one ( not made anymore) I will get a st5(224/218). Heads are stock series 2 for now might port them at a later date. Compression is 9.4:1.

I would like to do a 3" downpipe, would you suggest a t4 or expand out from 2.5 to 3" on the T3? I am most concerned about getting some boost on the line, I am used to launching with 12-14 lbs of roots boost, not sure how the car will respond to a vacuum launch. I would like to still 60' in the low 1.5 s range (or faster of course).

Thanks again for your help this is a new world for me, and I want to get the turbo right the first time.

 

[Turbo6Smackdown]

I'd go with a smaller cam. And if you're worried about spool up, there's the PTC converters that will spool a turbo like nobodies business, and dual bb billet turbos.

 

[kshef]

you might want to consider a 6076...they are cheap and you'll have room to grow. billets are nice, but with the 9.4:1 compression i dont know if it'll be $$ well spent unless you crank the boost way up there?

I would like to do a 3" downpipe, would you suggest a t4 or expand out from 2.5 to 3" on the T3? I am most concerned about getting some boost on the line, I am used to launching with 12-14 lbs of roots boost, not sure how the car will respond to a vacuum launch. I would like to still 60' in the low 1.5 s range (or faster of course).

there are v-band flanges that accept a 3" pipe and bolt to T3 v-band turbos

 

[SlowFiero]

With the smaller turbo wouldn't I need to run more boost to make the same power as the 62mm? That would be worse with the compression than the 62mm at a slightly lower boost. Also I haven't seen anywhere that the 60mm is cheaper than the 62.

I would like to get a 211/212 cam as I believe it would work well without pushing the powerband too high. The heads are decent right out of the box on the series 2 engines. Unfortunately they have discontinued the st2 and st3 cams that I think would be good. So it is either a st1 (206/206) or at st4(224/218) or st5(230/224) that is available. People say that they are all streetable on this engine but I don't really want to be shifting at 6500+ rpm anymore. Also think the bigger cams would probably be better with a larger 67mm+ turbo to feed the high rpm. I am trying to see if the original producer of the cams still has a st2.

I believe your ptc converters are built on our 245mm cores. If the Neil Chance converter doesn't work out I will probably go with a ptc. I know they are building them for the 4t65 now through triple edge performance and Dave there highly recommends them.


Where can I find the T3 to 3" vband flange?

 

[kshef]

With the smaller turbo wouldn't I need to run more boost to make the same power as the 62mm? That would be worse with the compression than the 62mm at a slightly lower boost. Also I haven't seen anywhere that the 60mm is cheaper than the 62.

you said you wanted to make 450whp? don't think there will be much, if any difference between the 2 at low boost press. a 6076 is $599(full throttle speed, g-body)...great option especially at that price

I would like to get a 211/212 cam as I believe it would work well without pushing the powerband too high. The heads are decent right out of the box on the series 2 engines. Unfortunately they have discontinued the st2 and st3 cams that I think would be good. So it is either a st1 (206/206) or at st4(224/218) or st5(230/224) that is available. People say that they are all streetable on this engine but I don't really want to be shifting at 6500+ rpm anymore. Also think the bigger cams would probably be better with a larger 67mm+ turbo to feed the high rpm. I am trying to see if the original producer of the cams still has a st2.

that ST1 cam is nice. dont read into the clubgp logic too much...lotta cars with stripped interiors, heads, big cams, pt67s & 70s running 120mph

I believe your ptc converters are built on our 245mm cores. If the Neil Chance converter doesn't work out I will probably go with a ptc. I know they are building them for the 4t65 now through triple edge performance and Dave there highly recommends them.


Where can I find the T3 to 3" vband flange?

2 different companies...triple edge sells precision converters...not the same


v-band flange
Weld Flange V-band 2.5" - STAINLESS STEEL : atpturbo.com

 

[SlowFiero]

Oh, I see a cast wheel 6076. I thought you ment a billet 6076.

How much boost is a 6076 going to need for ~450 rwhp? 610 fwhp would be pretty close to 450 rwhp, and that is the rated max for the 6076. I believe tim made 478 with a 60-1 t4 but that was at 28 or so lbs of boost. The 6262 could probably do that around 20-22 lbs with a good cam, or am I way off? I am planning an air to water Intercooler and meth injection, so hopefully that will be realistic boost numbers for my final setup. I am running air to water now and can run 13-14 lbs off an <50% efficient m90 setup.

If my thinking is way off please let me know.

Yeah I have always wondered why the clubgp guys run such huge turbos for the times , but I guess lag is one way to keep a fwd car from spinning all the way down the track. that is why I am not asking over there, I'm sure I would need a ST5 with a 67 or 72 mm turbo if I ask them:biggrin:

Does PTC make converters for 4t65, I guess they probably can make anything if you pay for it.

That flange will accept a 3" pipe or you have to adapt to it?

Thanks again.

 

[SlowFiero]

What is your setup? Your screen name seems very familiar, but I can't place from where.

Thanks again.

 

[kshef]

Yeah I have always wondered why the clubgp guys run such huge turbos for the times , but I guess lag is one way to keep a fwd car from spinning all the way down the track. that is why I am not asking over there, I'm sure I would need a ST5 with a 67 or 72 mm turbo if I ask them:biggrin:

to their credit most don't run a whole lot of boost...some run pump gas too. but when you see full weight GNs with PT67s running 10-15mph faster with less stuff its kinda ...some of the TA49 cars on the site could spank 99% of the turbo wbodys with cams/heads/big turbos

dusty from ptc said he would look at a 4t65 converter...i'll let you know what he says

the 3" pipe welds to the flange

i have a 50mm T3 turbo, non-intercooled, stock heads/cam/trans...ran 13.4 112mph on a terrible 60ft at about 16-18psi, ~4080lb. race weight. alcohol injection is awesome...i'm at 22psi now on pump gas....think i'll pick up at least another mph

 

[SlowFiero]

Is that a series 2 engine? Fwd park avenue? By mph that is close to 390 hp, pretty good. I was running 117-118 mph at 3050 lbs. Hopefully I will be able to break 120 with a turbo. Can't run any quicker, already 11.4x, and no roll bar. If the car performs well turbo, I might think about a bar, then I can atleast run to 10.0.:biggrin:

 

[kshef]

yes series 2 FWD park ave

IF it runs 120mph? most stock motor gtps with 60's run 114-117mph at 3600lbs. post pics/vids...that thing is gonna fly

 

[SlowFiero]

I don't want to be too cocky about the new setup, it might fall on it's face and not make any power.

I put down 336 RWHP at `3000 feet, even if I can make ~400 RWHP at '3000 feet, I will be faster than my car is remotely legal for. But rolling off the line, and running 12's at 12x MPH could be fun as well. Plus it should be plenty fast enough for late night activities on back country roads. It's hard to beat mid engine, rear wheel drive for traction.

I was pretty much at the point where I needed to spend 2700 on zzp aluminum heads to make anymore power, or go to another power adder. I decided in the long run turbo would give me more power, more reliability, and more headroom for future upgrades. Plus no one-off cylinder heads, that will probably be unavailable after they sell the last 12-15 sets Zooomer said he has in stock. It would suck to spend that much on heads, then burn one, and have no way of replacing it. This way I can make the same power, with stock GM parts, with plenty of replacements around.

Thanks again for your help.

 

[Dusty Bradford]

to their credit most don't run a whole lot of boost...some run pump gas too. but when you see full weight GNs with PT67s running 10-15mph faster with less stuff its kinda ...some of the TA49 cars on the site could spank 99% of the turbo wbodys with cams/heads/big turbos

dusty from ptc said he would look at a 4t65 converter...i'll let you know what he says

the 3" pipe welds to the flange

i have a 50mm T3 turbo, non-intercooled, stock heads/cam/trans...ran 13.4 112mph on a terrible 60ft at about 16-18psi, ~4080lb. race weight. alcohol injection is awesome...i'm at 22psi now on pump gas....think i'll pick up at least another mph

I'm back from vacation and will be looking into the options for this today.

 

[Dusty Bradford]

I'm back from vacation and will be looking into the options for this today.

We did not have a 4t65 converter in the shop but looking over everything. I would need a 245mm core sent in so it could be restalled. The 258mm won't be able to go very loose.

 

[SlowFiero]

Would these be furnace brazed, stronger stators, etc? There was a company restalling stock converters years ago and M90 cars would destroy them with ~300 whp.

This is the most widely used converter in the fwd market. But the slip Akita on the top end.

ZZ Performance


I had a 3500 stall in my car. Could get 2800 on the foot brake(3050 lbs), ****ty fire brakes. But had to hit 6500 rpm to get slippage below 10%.

I have a Neal chance converter now that will foot stall to 2500, flash to 4200, and gets 10% slippage around 6000. Still not spectacular considering my actual whp at this altitude is only 335, and car weighs 3000 lbs. I can't imagine what the slippage is like on a 3600 lb grand prix with 400-500 whp with a turbo.

I have some logs that I could send you showing a stock sunfire converter, a zzp 3000 stall and a zzp 3500 stall and the Neal chance converter if you wanted to take a look.

Thanks