basic non IC turbo tech

[SNEAKY]

i am not working on a Buick, but i figure some basic tech should cover many brands.
i am almost through building a JY twin turbo set up for my mustang. i am using two T3's from a TurboCoupe with .63 housing. my current set up is stock HO heads and a stock cam. my compression ratio is 8.5:1 . my main question is how much boost would be safe with out an IC on pump gas. my original plan was to just run the factory wastegates and not use a controler to up the boost.


BTW my tuning device is a PMS, it is made by, www.efisystems.com it uses a map sensor like the GN's to sensor boost and i can adjust timing and fuel curves from there. and i am running 42lb injectors.

 

[JDEstill]

Well, Corky Bell's book has a graph that indicates 8 psi or so for a nonIC car with 92 octane. But that thing is so generic, and there are so many variables, that I'm sure it is just a stab in the dark. What do the hot airs run stock, 12 psi or so? I would think you could run somewhere in that range. I'd start off at 6 or 8 psi and slowly work your way up. Got any way to tell when you are at the limit, ie a knock indicator of some kind?

I guess you could do the "torque it till is strips, then back off half a turn" method, ie crank up the boost till something breaks, then rebuild it and turn the boost down a few psi from that

John

 

[SNEAKY]

the factory wastegates are at ten psi. i do have an IC but i need to modify it for it to fit in my mustang.