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2500 rpm afterfire
Posted: Tue Sep 27, 2011 11:03 am
by bmcewen
When i have the car in park and rev up to around 2400rpm(35kpa) its fine, once i hit about 2500 it starts popping alot. i believe this is called after fire like the fuel is igniting in the exhaust, the pipes get very hot. I have tried more and less fuel 14-16 afr and more or less timing 30 -50 degrees so far it's always the same thing 2500 rpm pop pop pop
Re: 2500 rpm afterfire
Posted: Tue Sep 27, 2011 3:30 pm
by Hahns5.2
Can you post your MSQ?
Re: 2500 rpm afterfire
Posted: Tue Sep 27, 2011 5:18 pm
by bmcewen
I will get a log file up tommorrow morning
Re: 2500 rpm afterfire
Posted: Tue Sep 27, 2011 5:59 pm
by Hahns5.2
First thing I see is your VE table is pretty unorthodox looking. Your VE rises mostly with RPM instead of RPM and MAP.
It should look like something closer to this.
Re: 2500 rpm afterfire
Posted: Tue Sep 27, 2011 9:05 pm
by bmcewen
That's cause I've only played with it in park, haven't driving yet because of the popping
Re: 2500 rpm afterfire
Posted: Wed Sep 28, 2011 9:34 am
by bmcewen
Here is a log with a new msq. it wanted to run different this morning but still the same problems
Re: 2500 rpm afterfire
Posted: Wed Sep 28, 2011 4:40 pm
by Hahns5.2
First, is your CLT correct? If so that's pretty hot.
It looks like it's going lean and breaking up, probably related to your VE table. Doesn't look like you have an IAT? If not, the MS box thinks the IATs are 170* all the time, making it run even leaner.
Re: 2500 rpm afterfire
Posted: Wed Sep 28, 2011 6:09 pm
by bmcewen
No the coolant is not correct i have an indash analog mechanical temp gauge that's reading in normal range...Yes I have an iat it's mounted in the bottom of the holley stealth ram and it's possibly heat soaked, so 170 sounds accurate but i believe that the iat corrections are all turned off. I seem to be having alot of electrical gremlins and i'm not sure why, all my grounds are soldered to the same lug bolted to the back of the cylinder head, allthough i did move the battery to the trunk which is grounded to the unibody/frame, i'm not sure if that would cause problems or not
Re: 2500 rpm afterfire
Posted: Wed Sep 28, 2011 6:51 pm
by Hahns5.2
Odd, I'm not able to find any MAT data in the log so I assumed you had no IAT
MAT corrections cannot be turned off, it's part of the code, it can be compensated for in the MAT correction table however.
Re: 2500 rpm afterfire
Posted: Wed Sep 28, 2011 7:00 pm
by bmcewen
I was referring to the iat-based corrections under other tuning in megatune. Don't think I've ever seen any type of mat table
Re: 2500 rpm afterfire
Posted: Wed Sep 28, 2011 7:33 pm
by bmcewen
After looking around I believe the mat tablesmight be an EXTRA thing