Moving fuel cut up with a SAF-C

[Mk3Les]

Ok here’s what happened. I took my car in to get the SAF-C tuned yesterday. All I’m looking to do is move fuel cut up to 14psi instead of the 10psi I’m getting now. So the dyno operator runs it up onto the dyno does a few runs then heads off to see the boss. He comes back 10mins later and asks me if I know anything about cars, then goes on to say that I can’t get my SAF-C tuned on a 7mgte! Draws a very nice graph on the back of a piece of paper and starts to tell me that when you pull fuel out the ecu advances the timing (I know this) so he couldn’t increase the boost as the motor was knocking too much already. He then disconnects the SAF-C and pulls my car off the dyno and hands me a bill for $100!
So the question is how hard is it to tune a 7m to run 14psi of boost with a standard amf and a SAF-C?
I know it can be done, I guess I just want some ammo for the next time I try to get my car tuned.
On the up side I did get a dyno graph and with the SAF-C I managed to get 202.8 kilowatts (271 HP) at the wheels. With only 10psi of boost.
I’ll list my mods below just in case anyone has any thoughts on this one.
Stock ct26, K&N filter, 3inch dump and exhaust, 2.5inch intercooler pipes, HK$ intercooler and an untuned SAF-C!

 

[ILikeCarsYesIDo]

If you're getting fuel cut at 10 PSI, you have a boost leak.

 

[jtran8]

do you have wideband ? i think you have boost leak some where . check for boost leaks before any thing else . my previous set up same as yours except without safc , i backed out screw on stock afm ran 14psi of boost without fuel cut on stock ct26 and hit fuelcut at 16psi temperature was 40degree F . check all clamps to make sure they are tight .

 

[Mk3Les]

do you have wideband ? i think you have boost leak some where . check for boost leaks before any thing else . my previous set up same as yours except without safc , i backed out screw on stock afm ran 14psi of boost without fuel cut on stock ct26 and hit fuelcut at 16psi temperature was 40degree F . check all clamps to make sure they are tight .

DAM!!!!!!!! I think you guys are right. I'll check the clamps and pipes. I was just thinking about it and I dont remember if I checked any of the clamps after I put my intercooler in. Thanks :icon_redf

 

[dbsupra90]

time to find another shop.

ive tuned countless 7m supras with an s-afc.

he is right about timing advance, but that really doesnt effect anything until you are pulling 20% or more from the air signal.

after you get the boost leak sorted id find another shop to tune it.

 

[dugums]

You should be able to find a good number of threads about people running a SAF-C. My car was tuned with a SAF-C and runs very well.

 

[robbo185]

If your hitting fuel cut its for a reason. If the motor was knocking bad at 10psi you have a problem somewhere. Also I wouldnt turn the boost up to 14psi until you get some fuel mods. A walbro 255 fuel pump should be sufficient for that boost level.

 

[Mk3Les]

Hey guys thanks for the advice, it was a boost leak. I tightened every clamp on my intercooler pipes this afternoon as well I backed out the screw on the afm and guess what fuel cut had been raised. I was hitting 15 to 16 psi before it cut in, I backed it off to 14 on the high setting and left it at 10 for normal driving. I’m leaving it on 10psi till next Tuesday when it goes in for another tune (different shop this time) I’ll see how it goes then. Thanks again for the help.