zero degrees timing advance!?
Thread Starter
TECH Enthusiast
Joined: Mar 2002
Posts: 630
Likes: 0
From: York, PA
zero degrees timing advance!? Has anyone ever seen 0 deg timing advance??? We have a blow-through maf design on my single turbo ls1... Everything was reading fine, showing the correct High-Octane timing advance at 12psi, maf and map were maxed, everything was lookin ok... but then we made a change to the VE table, uploaded the tune, and now the timing goes to 0 degrees advance. I changed the VE table back, and the car still runs like ****... not boost related because it'll go to 0 before 1psi most of the time. What could be doing this? Changed everything back to what it was before, pulled a file to see if it was corrupted, but the data is fine...timing tables are ok. Just something has gone haywire where under load, the timing goes to 0. 
hptuners was used beforehand to make changes, but we're now using my ls1edit... could it be a conflict between the two? I have had it and am about to just buy bigstuff3, yet I can't afford it.
hptuners was used beforehand to make changes, but we're now using my ls1edit... could it be a conflict between the two? I have had it and am about to just buy bigstuff3, yet I can't afford it.
During my very first attempt at SD tuning I had my MAF unplugged and at random times my timing would drop to 0. Low octane table did not show zero at all. Plugged the MAF in and set the maf fail frequency to 0 and it never happened again.
Have you checked all the correction tables(iat temp, ect temp etc) to see if the pcm is removing the timing for some reason?
Have you checked all the correction tables(iat temp, ect temp etc) to see if the pcm is removing the timing for some reason?
Thread Starter
TECH Enthusiast
Joined: Mar 2002
Posts: 630
Likes: 0
From: York, PA
mmmmm, it could be maf related then... My fail freq is stock (11k or whatever). maf is plugged in, but maxes out of course... hmmm. I dont think we fooled with the correction tables... will have to go and look again later on.
The only thing I can add is that when you look at the H/L timing tables with edit, they are whole number and one decimal place, and with HP Tuners, they are a whole number only. Maybe it is the way the data is written with the different programs with the decimal place. Just stabbing in the dark here.
I attempted to edit an ls1edit tune using hp tuners the other day. All the data was skewed. I'd look into that. I think ls1edit changes the way data is written in the pcm.
Yet another reasn hpt > ls1edit
Is HPT still doing ls1edit/efi live buybacks? If so you can get hp tuners for a lot less than $500
Yet another reasn hpt > ls1edit
Is HPT still doing ls1edit/efi live buybacks? If so you can get hp tuners for a lot less than $500
