The only GT40 to go with now is a GT4094. Spools faster than a dual bb 67 a.k.a. 37R, and is good for upper 700 awhp somewhere in the 40 psi area. the 4088 will spool faster, but it runs out of breath sooner vs. the 4094. The only downside for the T3 guys vs. a 67 is it has to be in a T4 header.

 

I have used a Gt4094 and a 4088 on the same Cosworth engine and the 4088 won hands down, it pulled 30hp more everwhere than the 94.

Mark

 

4094r isn't too great IMO. We have one on a car, spools like a 42r. Did make 820whp but fell off hard. 4088>4094

 

Can you send me datails on your turbo kits for evo's .

Mark

 

Mark... i just figured out who you are LOL!

MADevelopments
Mark Shead...i tried to get response out of the MLR on a thread i started and not much info there.

i still think a 4088 will spool qiicker than a 35r Single Scroll
if it can make the same power and a bit more and spool faster than a 35r, this is the way forward.

Geoff from Full race will also tell you that the 4094 is not a ver efficient turbo.
his money would be on 4088 and for quick response and spool 35r TS T4

 

Yes the TS 40 will spool better than the 35 but it will not make much more power,
I will be trying other makers kits soon to see if that changes,
I will be testing a TS35 t4 flange within 2 weeks and will be tunning to no more than 500ish hp so will compare the spool on it,
If I had to choose between a TS40 and a open scroll 35 based on the same power the ts wins for spool,
So far in my testing on Evo kits the TS doesnt blow me away, But on the Cosworths I do it does and worth it.

Mark

 

cool cool!!
please post back your fidings mark

dave is also about to finish a 4088 on a his stage 3 block and head with a FR kit.
with the Fr kit it a matter of swoping out the turbo with a t4 flange 35r...

Decisions decisions......

 

that spool up nasty

 

is that on a t4 flange...

 

if it can actually mimic the spool up like this on the road.. it will be awesome.

yes, The TS full race kit is on a T4 flange

 

Guys if you pay attention, Mark has already quoted you spool numbers on the road in this thread. He has mapped two FR 40R kits I think... one on the road, one on the engine dyno... different cars. The one mapped on the road is one of his customers who competes in Time Attack in the UK and won the club class last year on a 4 year old engine built by Mark!

 

I believe the new turbo brand to go with are Borg Warner turbos which all come twin scroll and with their ETT (Extended Tip Technology) which allows for faster spool and more top end. If any if you speak with Geoff from Full-Race ask him how he feels about Borg Warner and he will tell you that they will give Garrett's GT series a huge challenge to come up with a better turbo design.

Here is a link from FreshAlloy.com comparing a BW S374 to the GT40R.

http://forums.freshalloy.com/showthread.php?t=179645

 

nice results mark! guys Mark is a tuning master. his tuning alone probably got the turbos to spool 500rpm sooner and make more power up top!!

Chris.

 

were you able to do more tests?