Thread: Hitting 13AFR, anyone ever ran 9.5:1 map on 8.5:1 setup?

high pressure can sometimes cause the injector to have a slower open time and maybe less fuel. close that qtech.

Yes, I was running 3.2 bar with my walbro and hitted around 1:10,5 @ wot.
So I turned down the fuel pressure during a dyno session to a final 2.7 bar. Gaining about 12 whp and a 1:12 a/f ratio.

i wouldnt be hitting the top end, those type of air fuel ratios will grenade your engine, or cause extreme damage... 12:1 MAX most tuning places wont even go past 11:8:1 for safety reasons, so when you go into the 13s, you run alot of risk of blowing the engine

I see 12.5:1-12.85:1 around wot on my UEGO too on a JWT Z32/STi-4bar program. I pulled the plugs and they are a nice healthy tan. I've been running with those readings for over a year and I think it might just be the UEGO thats not reading correctly.

I quit.

placement o the wideband sensor ill also play a roll n weather or not your readings are overly rich or lean depending on how close or far you put the sensor on the downpipe will depend on the readings

Just thought of something. I don't know how the Uego is wired up, but I know that for my LC-1 all grounds should be at the same place (for the whole system including sensor), and the wires are ideally soldered to a single eyelet which is grounded. Also, you're not supposed to twist the ends of different wires together when grounding or connecting to the same source. Also make sure the ground is a really strong one.

I know that for the LC-1, failing to take the above precautions can often result in an incorrect reading because of electrical interference. Worth a shot to check out your wiring and make sure it's good.