Running lean, a frickin mystery.

[Vegas Smith]

Mods are in profile. After i put in the small 16g and ported everything out i have been running very lean. I took care of ALL my boost leaks. I have the wahlbro 255hp, sx regulator, even have fpr raised to 47psi!.....put in freinds old 450 2g injectors. re-wired fuel pump and am only losing .4 volts after relay. In the 3rd gear pulls i get a check engine light. Last time it was logged i was getting like 20 knock at 17 psi.....im running even less psi now. Anyone having any other ideas....sorry for the unorganization.

 

[Woody91GSX]

Need MORE fuel, or timing problems. See if you can get some 550's to test. Fuel pressure might be high. See if about 43 does any difference. When changing fuel pressure, unplug the vac line and hold your finger over it so the engine doesn't rev higher. Do you have a pocketlogger? Knock indications would tell me I need more fuel. That's how I tuned my MAS and Translator.

 

[Vegas Smith]

Thats the thing, changing the fp does nothing. i have no afc so buying 550's wont make it easier because it will just be ultra-rich. plus, thats not the problem, i dont NEED 550's, 450's should be fine. I wouldnt be fixing the real problem.

 

[Woody91GSX]

If you're knocking 20, you need fuel. Then you'll come closer to stoich..
Do you have an A/F meter?

 

[Vegas Smith]

Yes, i have one and its a worthless pos.

 

[1LE]

Originally posted by Vegas smith
Thats the thing, changing the fp does nothing. i have no afc so buying 550's wont make it easier because it will just be ultra-rich. plus, thats not the problem, i dont NEED 550's, 450's should be fine. I wouldnt be fixing the real problem.

Mmmmm, I dunno about that... I really think you should have 550s (and some method of controlling fuel) at that level of boost with a 16g. On pump gas a 16g at max usable boost actually works better with 660s... 550s are borderline...

 

[Vegas Smith]

I understand that it would be better to have 550's and an afc but you dont need them to have a properly runing car.My brother has the EXACT same setup plus a front mount and his has no problems running lean. Im sure 550;s will help once i fix this problem but it isnt the problem. Im going to get a cockpit fuel pressure gauge so that i can see fuel pressure when i hit boost. The car was logged with something like .21(?) milliseconds(?) for the injectrs at 4k rpm. It seems like the fuel pressure isnt raisng when i get boost.

 

[1LE]

Yes, I suppose a faulty FPR, or maybe even a damaged/leaking/clogged vacuum hose to the FPR could cause that results?

 

[Vegas Smith]

Well thing is that this is a brand new Bruschur aeromotive regulator( the badass one on the thier site). Im going to try my old 1g reg in a day or two to see if that helps. Checked the lines and none are being pinched or anything. Maybe my whalbro is defective all of the sudden?

 

[Puller]

IMO it's as simple as just richening things up with an safc..i don't know why you wouldn't have one by now especially with that fuel pump and what not...but at any rate i think you should just lower your boost a couple pounds and when you get one go from there. Tuning with an SAFC is ridiculously easy so i think that's your best option.

 

[thehyena]

get 550's at least

 

[LandoAWD]

You can't just slap 550s in...invest in an AFC and make adjustments to your delivery. You may even be able to make the 450s deliver more with the raised FP and an AFC, but 17 psi on a 16g and 450s with no fuel control is asking for trouble.

 

[thehyena]

maybe that's why im running rich

 

[91TalonTSiCT]

RULE#1-Do NOT perform modifications without any way of monitoring the effects.

That's like the cardinal rule of modifying. Every car is different too. What works for one person may not work for another.