goombadi99

To make a long story short I supercharged my car and had it tuned at a very reputable shop locally. My car made what I thought was pretty low Numbers. Long tube headers, catless x pipe, ported throttle body, and ecs supercharger novi 1500. Car only put down 452 on a "conservative " tune. Well last night I took my car to the track and a friend data logged my car after numerous complaints about it falling flat in fourth gear. Low and behold the tune is showing only 10 degrees of timing and when shifting into 4th I am getting 9 degrees of knock retard and shows only 2 degrees of total timing until almost 5000 Rpms. I'm a little disappointed that all this money spent shaved 7 tenths off my 1/4 time. Now I know I need better tires but I should be trapping a lot faster than 112mph. Stock I was trapping 107. I really hope this is due to the tune. !!

DOUG @ ECS

Rochester is a bit of a drive to us, but I'll be glad to assist if necessary.

I would suggest starting with a couple of Sea Foam treatments directly into the intake. Let the entire can get used threw either the brake booster or EVAP inlet and let it sit for an hour after.
It will smoke the neighborhood out, but it is very effective.

Keep data logging each time and see if the knock lessons, continue until it's completely gone. I have had to do some cars 3-4 times before it clears then up.

GLWI

goombadi99

Does 10° total timing seem a little on the low side? I would assume the 9° knock that I am loosing a tone of HP in 4th gear but only having 10° in first through 3rd seems low to me.

DOUG @ ECS

Were you at 10* with 9* of knock, or were you at 1* after getting 9* of knock?

If your requested total timing is 10* then yes I would consider that low, if you are getting 9* of knock with that timing then there is most likely a carbon issue. Hence the Sea Foam.

goombadi99

I was getting 10 degrees total when car runs great 1st through 3rd. In 4th I get9 degrees knock retard giving me a total of 1 to 2 degrees total timing in 4th until about 5300rpm. Hope this clears the confusion. I'm assuming the tuner put my timing at 10 degrees total to keep the tune conservative

DOUG @ ECS

Ok so then there must be a carbon issue which is why they may have thought it needed timing so low. All with good intentions for you, but the car should be able to handle more then that. Let alone 9*'s of knock is bad, it's almost maxing out the knock table.

Get that taken care of and data log some runs until you see the knock dissipating. Report back if that doesn't fix it and we'll go from there.