Ok, I did some research and decided to go with a gt42r for my 20b motor. I want a street car with a goal of 600whp. Now I'm second-guessing that my gt42r might be too big (and laggy) for street use. What do you think?

a forum member was using it on a bridgported 13b.... and said he had amazing results



i would imagine you'd get a better performance as far as spoolup time and power with the 20b.



message TYSON about it

the gt42r should work well for your application and hp objective. it flows approx 82 lbs/min or 1186 cfm.



the rotary needs approx 1.86 cfm to make one flywheel hp.



1186/1.86= 637 flywheel, 542 rear wheel



another method 82 times 10= piston flywheel hp/1.3= 630 rotary flywheel, 536 rear wheel.



obviously the above formulas are a guide but generally work well. your 20b will easily power the gt42r... there are other turbos as alternatives... just look for something that is efficient around 80 lbs/min at the boost/pressure ratio you want to run.



howard coleman







quote=FikseRxSeven,Feb 17 2005, 09:42 AM]

a forum member was using it on a bridgported 13b.... and said he had amazing results



i would imagine you'd get a better performance as far as spoolup time and power with the 20b.



message TYSON about it


[/quote]

ANYONE WHO SAYS A GT42R IS LAGGY ON ANY ROTARY HAS ONLY SEEN PICTURES.





THEY HAVE NEVER DRIVEN OR BEEN IN A CAR THAT USES ONE.







https://www.nopistons.com/forums/pub...1047683358.gif





Howard,



The smaller GT42 compressor wheel will produce 590 at the wheels. I have not seen a dyno of the larger wheel maxed out to see how far it goes. https://www.nopistons.com/forums/pub...IR#>/smile.png I think it would be a specatacular choice for a 20b.

ok, thanks for the reasurance. I became concerned when I heard gt42r is too big for supra (2jz).

GT42R too big? **** I'm almost inclined to say it's too SMALL!

Not after you try stuffing it under the hood of a Subaru. There only LOOKS like there's lots of space in there!

Isnt that **** annoying? https://www.nopistons.com/forums/pub...IR#>/wacko.png

OK ill put my 2 cents in. The GT42r is a serious peice of gear and will match great on a 20B lots of people run them. So stick with what works and being a Garret item it's as good as it gets all the pros run them, hybrid bitzers and what not.

Just keep the turbine big 1.15 it's big but not to big if ya realy want to 1.22. Just get one it will be the best choice ya make. I do also realise they are expensive.

Dont do what I did and spend foreva picking and looking cos at the end of the day ya waste to much time picking turbos that will easy make power that we can afford. T6 flange 2.

GT42R is a good choise for a 20B. We have made 700RWHP at 19lb's boost. 1.2 hot side