interesting... if you like to blow your car up

[tsipsi20]

Well guys, I finally got the AFC2 hooked up, and the pocket logger. I made my first run the other day... you're not gonna believe the results. It's discusting, really. With the AFC zeroed out,3rd gear, @12 lbs (35 degrees), here's what i got...

RPM - 2000
TIMING ADVANCE -26
KNOCK - 0
________________
RPM - 3000
TIMING ADVANCE -22
KNOCK - 9
________________
RPM - 4000
TIMING ADVANCE -16
KNOCK - 26
________________
RPM - 5000
TIMING ADVANCE -13
KNOCK - 22
________________
RPM - 6000
TIMING ADVANCE -16
KNOCK - 28
________________
RPM - 6500
TIMING ADVANCE -13
KNOCK - 28
________________

clicking into 4th gear for a second...
RPM - 4968
TIMING ADVANCE -8
KNOCK - 33
________________


When I got home, all I could think is "What the FU##"!? Honestly guys, I think my car is going to shit. HELP!!

[EDMUND65]

I don't understand those numbers, but soon i hope i will

[tsipsi20]

Originally Posted by EDMUND65

I don't understand those numbers, but soon i hope i will

I wish i did too.

[crunchymilk55]

well it's pretty obvious why

First, you MUST get more data points. Just every 1000rpm tells us nothing. Get as many as possible and do a 3rd gear 30-100mph pull. Second, you're running 550cc injectors with a 0'd out AFC = bad, you're rich as shit.

I would bet you have a major boost leak somewhere. Those knock values are insane. Your timing curve sucks too, but more data points would help.

Take a better datalog and I'd be happy to help you out man. Good luck. Don't go WOT unless you're logging it IMO.

EDIT: I also saw you're not running a FPR with that walbro255. You'll need one to set baseline fuel pressure correctly in order to tune.

[kjewer1]

The 1g timing curve sucks even with no knock... Peaks way to early and then falls off in the top end. 28 counts of knock ispushing it, time to get that tuned out

[tsipsi20]

So's there's no way to tune it without a FPR? Cause i really don't have the money to spring for it now. I'd trade anyone for a 190 haha.

[kjewer1]

FPRs aren't for tuning, but your AFC is.

[tsipsi20]

Originally Posted by 95 GSXracer

FPRs aren't for tuning, but your AFC is.

But can you tune or not without the fuel pressure regulator? Do i have to set it to set base fuel pressure again before messing with the AFC??

[kjewer1]

Setting it to base pressure will help at low or no boost by putting the pressure where the ECU expects it to be. But at WOT a regulator that is being over run has no effect. The motor is consuming enough fuel that the reg can control what is left and maintain pressure. For example, if your base pressure wont go below 50 psi, and the ECU expects it to be 43 (2g), at everything over 7 psi it will regulate fine.

So for your WOT knock problem, the AFC will allow you to tune it out, unless it is a mechanical problem. The AFC being zeroed out is almost OK, since the 2g MAS almost balances out the 550s. But not quite. I would add 5% fuel and see if the knock goes away. If it does, or almost, you have a good start and can fine tune from there. If adding up to say 15% fuel doesn't help, there is something seriously wrong with air metering, fuel delivery (550s not 550s, etc), or it is mechanical (lifters).

[tsipsi20]

Originally Posted by 95 GSXracer

Setting it to base pressure will help at low or no boost by putting the pressure where the ECU expects it to be. But at WOT a regulator that is being over run has no effect. The motor is consuming enough fuel that the reg can control what is left and maintain pressure. For example, if your base pressure wont go below 50 psi, and the ECU expects it to be 43 (2g), at everything over 7 psi it will regulate fine.

So for your WOT knock problem, the AFC will allow you to tune it out, unless it is a mechanical problem. The AFC being zeroed out is almost OK, since the 2g MAS almost balances out the 550s. But not quite. I would add 5% fuel and see if the knock goes away. If it does, or almost, you have a good start and can fine tune from there. If adding up to say 15% fuel doesn't help, there is something seriously wrong with air metering, fuel delivery (550s not 550s, etc), or it is mechanical (lifters).

Say for example, that it is lifter tap, considering mine are noisy even at idle. Is there anything I can do then? I'm at my girlfriends house now, but i'm going to richen it up on the way home and see what happens. I'll let you know.

[kjewer1]

There is a lifter cleaning vfaq, but you can get a set of revised lifters for ~130 bucks, and the procedure to replace them is the same as removing them for cleaning. On the older 1Gs sometimes its easier to just replace them...

[scottsee]

3g or SBR inlarged lifters. $100-150.. I don't mind my lifter tick enought to do anything about it. Gets louder when i get low on oil, like a little warring signal.