Tom, I do know about turbine wheel size & housing size has a lot to do with boost control,that is why when you told me you had a .63 turbine housing I said to you that is way too small.
I was wondering IIRC,,,,your turbo manifold was devided & I suggested to mill the manifold devider & was wondering if you had milled it then tried it if it made any difference?
Or did you just install the larger turbine housing,or both?
All the SPA manifolds were devided like mine is & Douglas told me that is the way they come from them. He talked w/SPA & they told Douglas,that milling the devider did not make any difference because they had no boost control issues with the wastegate only seeing 3 cylinders.
The only comparasion I can talk about is from my Syclone. The factory put in a 2100 RPM stall converter.
For best performance it would have been better if it was a 2400 RPM,or there abouts.
The stock trannys(700R4) do not run hot at all w/a 2100 converter. It really dives like a standard low rpm torque converter. Just by driveing my Syclone around normal, you would thick the stall is around 1400-1600 RPM
The only time I get 2100 RPM is if I stomp on the brakes hard,give it a bit of throttle & watch the boost build up to 4 psi,from that point it will just stay @ 2100 rpm even if I go to 15 psi of boost pressure w/the brakes applied.
I know if my Syclone had a 2400 rpm converter I would be running 11's.
I just stay w/the stock one, just to see how fast I can go w/it.
I was wondering what size rear wheel cylinders you have? One of the first upgrades I did to my Syclone is install 7/8's rear wheel cylinders.
Being all stock I could only get about 3-4 PSI of boost pressure,then it would push through the brakes.
After I installed the 7/8" rear wheel cylinders I can hold 15-20 psi of boost pressure,huge improvement!!
Hope you get it to a track soon w/your looser converter,it will make a big difference.
Goodluck w/it & your tunning.
MBHD _________________________ 69 Camaro 250 EFI, turbo,12 port aluminum head.
