AJH LS1 Z28

OK.. here is the story.. I had a 382 bigbore motor put in by MTI last Dec.. All was well until the 3" y-pipe w\cutout was made and put on.. put it on the dyno it made NO power.. My timing was all of a sudden set at 21-22 degrees.. But my computer is programmed at 27.. Why would the computer not want to hold timing?

I have done some major ATAP runs and my LTrims are really high (7-10).. What affect would that have? I got some ses codes which have now been fixed.. but my computer still will not hold timing..

Things I have changed:

Both Knock sensors
Both 02 sensore.. are front and back 02's any different?

reprogrammed the computer many times with 28 degrees but it will not hold..

Changed injectors to SVO 30lb.. didn't work..
So now I am lost... Today I am gonna put a totally different computer in and see what happens..it looks like my computer keeps reading the Low Octane fuel table in LS1 edit.. but who knows...

Anyone have any ideas? <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />

on a positive note.. the A4 will be out my car in about 2months. I am bored.. I WANT A m6!! <img border="0" alt="[Pontiac]" title="" src="graemlins/formula.gif" />

Chris Jones

Are you getting knock when you ATAP it?

The other option is to increase the timing in the low octane table, a little risky though.