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1fastgto
December 11th, 2008, 12:47 PM
OK, I have a 416 stroker with an E40 PCM, in a 05 GTO. I have AFR225 heads and a pretty big cam with over 600 lift, and a FAST 92 with Kooks long tubes 1 7/8. I have 2 tuning issues, at light cruising in any gear I have bucking, when I am cruising a 50 or 60 in 5th or 6th gear light on the throttle it feels like a hickup. and its constant, never goes away.
The other problem is hot start, cold starts are perfect, starts right up. When hot starting it will start and then die. I have to give it throttle for a bit before it will idle. Any help would be great as this is my first post! Thanks!

Heres my current tune and log files. I am new and trying to learn. so if I am way off on something let me know.

4350

4351

4352

ssvolvo
December 25th, 2008, 09:30 AM
Welcome to the forums!

It doesn't look like your car has been tuned. Am I wrong?

As far as your stalling read this post from http://forum.efilive.com/showthread.php?t=6665Redline REDLINE and read the sticky at the top of this forum from GELF. Time to start with the VE tune after you adjust those idle tables.

Do you have a wideband installed yet? Stock injectors? Do LOTS of searching like we did when we started,. Rome wasn't built in a day.

After you dial in the VE and MAF, and correct the stalling that thing will drive so nice you won't be able to get out of it!

Good Luck, John

1fastgto
December 26th, 2008, 03:49 AM
Welcome to the forums!

It doesn't look like your car has been tuned. Am I wrong?

As far as your stalling read this post from http://forum.efilive.com/showthread.php?t=6665Redline REDLINE and read the sticky at the top of this forum from GELF. Time to start with the VE tune after you adjust those idle tables.

Do you have a wideband installed yet? Stock injectors? Do LOTS of searching like we did when we started,. Rome wasn't built in a day.

After you dial in the VE and MAF, and correct the stalling that thing will drive so nice you won't be able to get out of it!

Good Luck, John

Thanks for the reply, I have been searching here and there. Theres just so much info its hard to know where to start!

Car has been tuned, but it was tuned with another CAM in it. I have 38lbs Injectors with 65lbs of rail preasure. My LTFT are usually between 0 and -2.3 So I think I am good there. Or am I? No I do not have a wideband yet.

ssvolvo
December 26th, 2008, 05:27 AM
Well my mistake on the "no tuning" thing. Looks like a lot of changes have taken place. I think what took me off guard was your B0200 VE table looks stock but now I see the tuner just raised the values in the table instead of doing a proper VE. Surely your cam makes peak torque above 4400 rpm.
I don't think this is your stalling problem but it is time for you to install a wide band and perform a proper VE. I think a more accurate volumetric efficiency table for your cam would be less fuel at the lower rpms/low load and more fuel high rpm/high load regions. The only way to ensure this is with a wide band sensor. Also your PE B3618 looks backwards of what I would think it should be, and your B0156 would work better below 48%.
I think part of your stalling problem is the low amount of timing during idling. Hey you guys with more experience than myself please chime in here. Methinks if you could get the timing around 19 or 20 you'd have a better quality idle. By spending a bit of time with your log/tune I see something is pulling a fair amount of timing at idle. I know on my car with a small cam I fooled around with spark smoothing B5128-5132 to limit the amount of smoothing taking place which helped. Another thing you could do is flatline B5104 from 400-1200 rpm to 20 BTDC.
I'm not that good of a tuner but I've learned from my own mistakes and spent ungodly hours working on it. You will see when completed your car will be so much better to drive and more efficient.
There are lots of GREAT tuners on the forum here to help us all through this "black art", keep reading!

John