aves911
20+ Year Contributor
- 100
- 1
- Nov 13, 2002
Hey,
First off, I have a big16G, webcams street grind, supra SMIC, ported exhaust, and a full 6-bolt swap, 2.75" turbo back, boost controller is set to 16psi I have a denso pump with -6AN fuel lines and K&N fuel filter.
I was running 550cc injectors and I kept running lean at 16psi on 93 pump gas, would hit fuel cut badly at 4500 rpm. So I bought a set of 720cc in hopes of fixing the problem and running higher boost. But now, with the 720's when I floor it a 3000 rpm, 02 drops to .9-.88-.86 and by 3500 its at 0.82, timing is no higher than 5 degrees. The EGT's also rocket up to 1550-1600 by 3500.
If i lean it out, nothing really happens, if i richen it up the situation doesnt get better, then if i keep richening it, the car will bog when I go WOT. I know that running rich causes high EGT's, but my 02's are ridiculously low and keep dropping.
I don't know if any of you are familiar with running my kind of fuel setup, but the fuel filter has a 45 degree fitting that connects to the rail. Now when I listen to it, right by that fitting and the #4 injector there is a weird hissing, not as loud as a vacuum leak would be if the injector wasnt sealing agains the head. I also don't have any fuel leaks. I don't know what the hissing is? but that might have something to do with it.
At low throttle (cruise on the highway) AFC settings are normal for injectors that large, I am really confused. Any pointers would be great.
Thanks,
-Jacob
First off, I have a big16G, webcams street grind, supra SMIC, ported exhaust, and a full 6-bolt swap, 2.75" turbo back, boost controller is set to 16psi I have a denso pump with -6AN fuel lines and K&N fuel filter.
I was running 550cc injectors and I kept running lean at 16psi on 93 pump gas, would hit fuel cut badly at 4500 rpm. So I bought a set of 720cc in hopes of fixing the problem and running higher boost. But now, with the 720's when I floor it a 3000 rpm, 02 drops to .9-.88-.86 and by 3500 its at 0.82, timing is no higher than 5 degrees. The EGT's also rocket up to 1550-1600 by 3500.
If i lean it out, nothing really happens, if i richen it up the situation doesnt get better, then if i keep richening it, the car will bog when I go WOT. I know that running rich causes high EGT's, but my 02's are ridiculously low and keep dropping.
I don't know if any of you are familiar with running my kind of fuel setup, but the fuel filter has a 45 degree fitting that connects to the rail. Now when I listen to it, right by that fitting and the #4 injector there is a weird hissing, not as loud as a vacuum leak would be if the injector wasnt sealing agains the head. I also don't have any fuel leaks. I don't know what the hissing is? but that might have something to do with it.
At low throttle (cruise on the highway) AFC settings are normal for injectors that large, I am really confused. Any pointers would be great.
Thanks,
-Jacob
