Should have stayed with the Super 60...

[John B]

I been using my new Super 50/ stg.2 hybrid for a few months on the street now and miss the much faster response and midrange punch from the Super 60 I was using before. Is a Super 70 a compromise between these two or is it just as laggy as a hybrid?

[Keito]

Stage 2 wheel is better for flow, not so much for spool, depends on your setup though.
If your mostly stock, you found the disadvantage.
I installed an HY 35 last year, big change from T2, but I now have a 2.5, larger valve ported head, ported exhaust, custom intake and 3" exhaust to spool it.

[Ondonti]

How about trying a .48 housing? You can always swap back. Super 70 are a mixed bad that I would not want to get into. Some are terribly laggy.

[John B]

How about trying a .48 housing? You can always swap back. Super 70 are a mixed bad that I would not want to get into. Some are terribly laggy.

I'd have to get a .48 machined for the stg 2 wheel. How weird would that​ be?!

- - - Updated - - -

If your mostly stock, you found the disadvantage.
.

Honestly, there's not much stock left on this car.

[Pat]

I ran a 50 trim/stage III in a machined .48 housing on a 2.2 8v for a while and loved it for a street car. Never pushed the power limits, but at 18 psi, it felt great. I now have the same turbo set up on a healthy T3 in a Shadow. Looking forward to testing it at the track in the coming weeks, but so far, it's great. It's pulling great from 3500-6500.

I'd have to get a .48 machined for the stg 2 wheel. How weird would that​ be?!

- - - Updated - - -



Honestly, there's not much stock left on this car.

[tryingbe]

My GLH has a 2.5L with a T04E 50 trim with T04E compressor housing, stage 1 turbine wheel, and .48 turbine housing. Boost comes in at 1300RPM and Full 20psi comes in under 3000RPM.

I'd advise keeping the T04E compressor side but go back to a stage turbine 1 wheel and .48 housing, they are cheap and plentiful.

[John B]

Who would you recommend for machining the housing?

[contraption22]

I think people are finding out that the .48 housing isn't as bad as everybody thinks it is for a 8V car.

[John B]

I wonder if I can swap the turbo without removing the head? I ground reliefs around all the bolt bosses so they would be easier to get a wrench on, but still...

[shadow88]

I think people are finding out that the .48 housing isn't as bad as everybody thinks it is for a 8V car.

Not just finding it's not that bad, proving it too. I wouldn't go near the .63 housing for a streetable set up again.

[tryingbe]

My CSX has a turbo with a Stage II turbine wheel and .48 a/r turbine housing. Lots of top end but have no torque before 3400rpm...

[Vigo]

I would think a tbi header and upgraded exhaust would almost totally make up for the spool change from stg1 to stg2.. i am suspicious of something else going on in that situation.

Anyway, Yes you can get the turbo off without taking the head off. I did it to a shelby lancer about a month ago. It involves a lot of uncomfortable working positions. It's a lot easier if you take the k-frame out, but i didnt even do that, i left everything together. With the k-frame out it's borderline 'easy'.

I cant say i told you so because my memory is so bad that im not certain, but i THINK i remember trying to say that that turbo was pointlessly large for someone who wasn't really trying to make 350+ hp.

I would try getting a .48 housing machined and try that because it's not TOO expensive and it'll probably make a nice difference. If that doesnt work i would just go back to an s60/stg1/.48, which is still a 300hp turbo, so you should be able to run low-mid 12s before the turbo is your main bottleneck.

[JuXsA]

I don't remember the specs on the turbo on my csxt but it had a FM stg1 ported head, ported exhaust mani and I think the turbo was a T04 with a 46trim compressor with a stg1 .63 exhaust housing with a 3in SV. It would hit full bost around 3.5k rpms and would start building boost in the mid to higher 2k rpm range. It has been many years since I had it and don't remember fully.

Although it was a great turbo, I kinda wish I had done a super60 because thats a great turbo that bolts right on like stock and is perfect for a DD.

[turbovanman²]

TU can machine a housing, turbo shops or I can get it done for you but if you hate the lag, I'd keep the turbo and put a .48 housing on.

What cam are you running? Try advancing the cam, that helps tons with lag.

[trannybuster]

I don't remember the specs on the turbo on my csxt but it had a FM stg1 ported head, ported exhaust mani and I think the turbo was a T04 with a 46trim compressor with a stg1 .63 exhaust housing with a 3in SV. It would hit full bost around 3.5k rpms and would start building boost in the mid to higher 2k rpm range. It has been many years since I had it and don't remember fully.

Although it was a great turbo, I kinda wish I had done a super60 because thats a great turbo that bolts right on like stock and is perfect for a DD.

Same setup I have now with same kind of spool rpms...it must be the st2 trubine killing him.?...the turbine is the same between .63 and .48.....well the stg1 i anyhow..isnt the stg2 just and sligthly different angle (for lack of better word). You can use stock T2 turbine IF you machine down the compressor wheel .250, there is plenty of meat.

[turbovanman²]

Same setup I have now with same kind of spool rpms...it must be the st2 trubine killing him.?...the turbine is the same between .63 and .48.....well the stg1 i anyhow..isnt the stg2 just and sligthly different angle (for lack of better word). You can use stock T2 turbine IF you machine down the compressor wheel .250, there is plenty of meat.

Why would you machine down a stage II wheel? that's a waste plus they bigger not just in diameter. If you really want to machine anything, either machine a .48 housing or swap out to a stage I turbine wheel and .48 housing.

[JuXsA]

Same setup I have now with same kind of spool rpms...it must be the st2 trubine killing him.?...the turbine is the same between .63 and .48.....well the stg1 i anyhow..isnt the stg2 just and sligthly different angle (for lack of better word). You can use stock T2 turbine IF you machine down the compressor wheel .250, there is plenty of meat.

Yeah, my money is on the Stg2 turbine. The only reason to not go with a stg1 is if you are using a 16v head and can flow mad air, or its an all out all top end drag car and not a daily driver. The turbo you have and what I had is great for a DD but I still wish I had gone with a super 60 for the plug and play of it

[4 l-bodies]

I just sold a 2.2 with true s-60 in 86 GLHT. Heavily ported TBI header, head, intake manifold, upgraded swingvalve, cam, much tighter swish, etc. I had so much bottom end, I needed to kill some of it, so new owner is going with larger turbo and probably a bit more duration camshaft. Too much power down low isn't good either if you can't hook it up.
Mark Christofferson's fathers GLHT was eating stock TII turbos about one per year, due to overspinning them, even though boost was set at low 15-16 PSI. All the on and off throttle probably didn't help either. Finally went with s-46 in TO4B (FM style housing) w/stage 1 .63 housing and 3" TU swingvalve. Throttle response is critical in autocross car. We didn't lose that much low end punch going with that turbo. IMO, that would have been an excellent choice for you John. Bigger than a s-60 or s-70, smaller than your current turbo, and close to a bolt in.
Todd

[cordes]

Where are you achieving min and max boost right now? What is max boost right now? How much tuning have you done to work on the the spool etc.?

[John B]

I had so much bottom end, I needed to kill some of it,
Todd

Thanks for the tip. I have the .91 gear set and a Peloquin dif, so I can handle a lot of low end grunt better than some setups. I was considering the 46 trim, but when I went for the S50/stg 2/.63, conventional wisdom at that time was that it was about optimum for a 2.5. Gary Donovan told me years ago that many make the mistake of going too big on a street turbo and that he would use a Super 60 if he was building a street car. Shoulda listened...