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KEV 5 GT
21-08-2013, 23:46
just took car out for a blast after putting a t25 tomcat on drilled 2nd stage jet to 2mm and got a 0.9 ac jet standerd main jet running 15 psi and the afrs was 11.1 flat out in 4th gear how do i get it upto low 12.2

R5MJH
22-08-2013, 00:08
to lean it out you could put a 1.0 ac in but 11.1 aint seriously bad tbh 12.1 is best on wot or some prefer 11.8/9 matey

KEV 5 GT
22-08-2013, 00:20
or should i just up the boost abit will that help ? im looking to run 20 psi

gttjames
22-08-2013, 09:26
2nd stage to 2mm? hope this is a typo

normanlly people go 2nd stage 1.2mm, if more fuel need 1.3mm - if still more fuel needed start dropping the air corrector

KEV 5 GT
22-08-2013, 11:44
yes its a typo error lol i drilled it to 1.2mm should i take 2nd stage jet out to 1.3mm ? iam hoping to run 20 psi

TNT ANDY
22-08-2013, 12:56
just took car out for a blast after putting a t25 tomcat on drilled 2nd stage jet to 2mm and got a 0.9 ac jet standerd main jet running 15 psi and the afrs was 11.1 flat out in 4th gear how do i get it upto low 12.2

1mm a/c ?

Alex
22-08-2013, 13:39
Just turn the boost up and check the fuelling as you go.

SCHWARTZ
22-08-2013, 14:18
Just turn the boost up and check the fuelling as you go.

:agree:

R5MJH
22-08-2013, 14:20
1mm a/c ?
thats what i said matey to lean it out a little:laugh::agree:

gttjames
22-08-2013, 15:56
yer as above, you want 20psi area? and youv currently got safe 11.1 afr's - well turn the boost upto 17psi and take it for a run. and go from there

andybond
24-08-2013, 10:21
You cant safely keep on turning up the boost to match the AFR. You might be getting detonation and therefore risking the engine. You really need to be listening for this

GTphil
24-08-2013, 11:08
That carb spec should be ok for 17lb boost fairly safely, unless of course it's a high comp motor?

for 20lb boost it may still be ok but for me beyond 16/17lb boost a steth is a must, even then it's not easy to pick out the first signs of det. Often by the time you hear it the damage is already done.

You will also need to consider what fuel pump and fuel reg your using, and if they are indeed up to the job.