View Full Version : Question about tune

08-08-2006, 01:42 AM
today i had my car tuned, and the dyno guy said it was around 12 afr i think, tongiht i take it out for a run, and the afr on my lm-1 shows about 15 at near redline, and knock was about 216 at 100% on the s-afc 2, this is on a s13 redtop with gt2871R .64 ar, nismo fpr, duetchwerks 555cc injectors, and the other basic mods.

08-08-2006, 04:36 AM
WOW. I'd go back to the shop and give them a chance to rectify it. Might find some mechanical malfunction.

08-08-2006, 12:48 PM
Do some searching here driftts. Look for posts on Air Fuel and such. Try taking it back to the shop if you can to check the tune.......Fuel pressure ETC....

08-08-2006, 01:13 PM
what's the correction numbers on the SAFC?

their a/f sensor could've been clogged or something. happen to me once. my wideband was reading 11.3 ish and the dyno was showing 13+ AFR. after they cleaned the sensor and hose, everything was back to normal

08-08-2006, 03:23 PM
yea i got it retuned, richened up the high end to like 40 somthing %, fuel pressure is about 55 with the hose connected, afr is like 12 in the hot day, and 1.2 bar. feels much better.

08-08-2006, 03:25 PM
Booooo!!!! lean tune!

Hooooraaaaayyyyy Beer!

08-08-2006, 03:46 PM
Are running the stock ECU with Z32 setup? It seems weird you would need to add so much fuel but I guess if the wideband looks good and you don't see any specs on the plugs then have fun with it. Enjoy!

08-08-2006, 05:55 PM
was that +40% or -40% correction?

and isn't 55 psi of fuel pressure way to high? normally, with a bigger fuel pump and stock fpr, it's around 43 psi w/ vacuum line connected.

08-08-2006, 05:59 PM
You had your car S-AFC tuned? Yuck - I hated how much car drove when I tried it out(for curiousity). Ever thought of a ROM tune?

08-08-2006, 09:13 PM
i have a blitz denso 255 liter per hour fuel pump with deutchwerks 555cc injectors and nismo fpr and b&m fuel pressure gauge, enthalpy rom tune combined with s-afc 2 tuning.

here is the dyno graph, i got it retuned the afr is now at 12:1

08-08-2006, 09:16 PM
You had to bump the fuel that much with an Enthalpy tune? Maybe try contacting Enthalpy, I'm sure he can get you much closer to 11.8-12.0:1 AFR with a new burn.

08-08-2006, 09:29 PM
I'd check for boost leaks, first. (DIY Boost Leak Tester...)

08-08-2006, 10:41 PM
Nice numbers but something seems way off. The tune is probably off some since your original tune isnt for the cams. Another problem sounds like the shop isnt tuning right. I tune by my LM1 on the street. What does your LM1 read while street boosting? Its crazy how high your knock is going up. I still think you need to set your Fuel Pressure at 43.5psi with vacuum disconnected like its sopposed to be and tune the SAFCII from there.