turbo upgradebility?

[pwpanas]

Originally Posted by STRAIGHT-6R

What is the largest twin turbo set-up that a stock JZ2-TT will support? (exhaust gas psi and fuel cc...etc)

The largest "twin turbo set-up" that the stock fuel system (550cc injectors, US-spec Mkiv Supra Turbo) will support is the ct12b "twin turbo set-up" that comes with the 2jz-gte from the factory (aka the 'oem twins'). In theory, the oem fuel system (in perfect condition) could support a pair of turbos about 5%-10% larger than the 'oem twins', but unfortunately an off-the-shelf "twin turbo set-up" that's only 5%-10% larger than oem does not exist.

Also note that the only sequential "twin turbo set-up" available for the 2jz-gte is the 'oem twins'. ALL other (aftermarket) "twin turbo set-up"s are non-sequential.

With an upgraded fuel system, the biggest (off-the-shelf) "twin turbo set-up" that the 2jz-gte block will support is the HKS GT 2835 kit. Again, this kit is non-sequential which means this kit will spool up much slower than the 'oem twins'...both because the turbos are larger AND because they are non-sequential. I believe at one time, HKS did offer a smaller twin turbo kit (2530's?), but I believe at high boost this set-up would also exceed the capability of the oem fuel system. In theory, a person could purchase a 2835 kit, sell just the 2835 turbos, and then put a pair 2530s onto the kit. Not only would this still spool much slower than the oem twins (because it's non-sequential), it would not be safe with the oem fuel system.

In addition, note that "exhaust gas psi" is probably not relevant. I'd guess you mean charge-air psi (aka 'boost'). With HKS 272 cams, race fuel, and about 29psi of charge-air pressure, the HKS GT 2835 twin turbo set-up can put out about 775rwhp through a 6spd (that's about 910hp at the crank).

Lastly, note that "twin turbo set-up"s don't spool significantly faster than single turbo setups (of equivalent size). The "twin turbo set-up"s also cost several thousand $ more than a single turbo kit of equivalent horsepower capability (as you can see from the link I posted above, partnumber 1103-RT028US). Why are you specifically interested in "twin turbo set-up"s?