I'm looking at picking up a gt40 and looking for some advice on the exhaust. Wondering how much lag there is in the 1.19 as compared to the .94? Right now the motor is stock ported 87 FC but i will have it street ported in the future.

 

Going for the .94 exhaust side is stupid, IMHO If you look at the turbine flow maps for the GT40 and the GT35r, the GT40's .94 flows less than 10% more air, despite the fact that it's physically a much larger wheel. In other words, you lose a lot of spool capability and gain essentially nothing.

That said, the two options you should consider are a GT35r (flows like the GT40 .94) and the GT40 with the 1.19a/r housing (The exhaust wheel that comes with the 1.19 A/R housing is also different than the wheel for the .94 a/r housing I believe). For a motor with stock ports, the gt35r is the better option here, and even for a streetport I'd recommend against the GT40. My guess is that you won't see full boost until 4500rpm+ with the 1.19 as opposed to getting full boost around 3500rpm with the gt35r.

-Manolis

 

you should get the turbo and just bolt on a backside of .81 or .84 undivided/divided depending on your manifold.

 

won't fit

 

the .94 hot side GT40, even with the smaller compressor wheel will make well over 400rwhp. How is that stupid?

 

gt40 with the .94 a/r turbine housing is more than enough snail for a ported 13b if u feel froggy thro in a 88mm wheel for ***** and giggles. it will ultimately come down to how effecient your turbo system is.

 

the bigger the better

 

..hmmm correct me if am wrong.....but bigger = SLOWER too (spool i mean)

 

Speaking as someone with more experience with both than most. I would say go with the .94 for your street driving. You will loose some spool to a 35R but it will only be marginal with a optimal manifold on a good sized streetport.