Sound normal? Fuel cut/PSi?

Chris-Supra

New Member
Apr 1, 2005
168
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0
38
Minneapolis/Lakeville, Minnesota
Ok, car runs great and all just want to see if this was normal. Hear me out :)

My mods are-
K&N Cone Filter
MAF/T and 3" MAF
BIC DDP
Porsce 110 BPV
60trim CT upgrade

Stock ct26 will hit fuel cut around 12-14psi correct? I am hitting FC around 9psi with my 60trim. That would be normal correct? considering its pushing more air?

It just barely hits cut though, I took out 4% at 5500 on my maf/t and it eliminated the FC. (Car will get properly dyno tuned with wideband 02 next friday)

Also, what should I expect for hp/tq with my setup? I'm hoping for over 300, perhaps 325 would be nice. I have a MBC I just built and hope to max out the stock fuel system next friday. What should I expect for power?

Thanks
Chris
 

suprra_girl

7M POWAH! ;)
Mar 30, 2005
1,776
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0
Auckland, New Zealand
www.supra.co.nz
yep... i have almost the same mods just additional 2 1/2" hardpipes & big ass intercooler and i'm hitting cut at 9psi...
i would just give your ic pipes a checkover and make sure there aren't any leaks

with my setup i got 278whp.. but that's on our dyno's.. apparently ours read differently to yours
gl with the dyno :D
oh and i was running stock fuel system also.. was running 11.7:1 air fuel's with that setup :)
 

Bishop92t

Supramania Contributor
Apr 18, 2005
773
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USA
www.ma70.com
Correct, fuel cut will shift around depending on turbo. That's because FCO isn't based on boost, it's based on airflow, temperature, RPM and throttle position.
 

Chris-Supra

New Member
Apr 1, 2005
168
0
0
38
Minneapolis/Lakeville, Minnesota
Ok new question.

Got my car on the dyno and had boost creep problems creeping up to 14-15psi up high and the af's got up to 13 at that point (14-15psi) which is not cool. Made 346rwhp though :) so I brought the car home and ported my wastegate and no more boostcreep. Good. Now I'm wondering if this sounds right-

Got my maf/t have it set for 440's, and have idle and mid both set 2 clicks rich to keep the VF signal around 2.5ish while normal driving and wot -5% in maf mode (-5% across the board, I had it like this for the dyno too and af's were 11.2-11.5ish until 5500 when the boost creep starts, then everything got screwy).

Settings
Base - 2
Idle - 2
Mid - 2
Wot - F (-5)

With it set to 12psi and above MAF/T settings I can go without fuel cut on a warm day, at night when it cools off I hit fuel cut. If I take out another 2% in RPM mode I can just barely get by FC unless it gets really cool out.

Does this sound right or should I be able to boost higher? I'm trying to make the best of my current setup as I dont have the current funds to buy injectors yet. A walbro will be coming soon though. Perhaps my stock injectors need to be cleaned or I need a new fuel filter?

Also, If I am able to run with -5% across the board and get low 11 afr's and have the boost set to say 12psi on a nice day, could I clamp the signal to the ECU with the maf/t to eliminate FC alltogether and be safe on cool nights? I wouldnt want to be going too lean on a cool night.

Thanks
Chris