I recently got hp tuners and I am slowly learning how everthing works. I got my truck from a 15.30 @ 88 down to a 15.10 @ 89.5. But I havent messed with and fuel or timing tables. I think that is where the gain is. I have a 03 5.3 excab Z71. My mods are long tubes no cats, cutouts, cai, underdrive pulley, electric fans. my timing is around 24-26 degrees. If I try adding timing I get up to 2-3 degrees of knock retard. My question is can i run a ls1 timing table. Cause my brother has a 02 TA and he has the same mods and is running @ 32 degrees but he is also getting 3-4 degrees of knock retard but it doesn't seem to slow him down. Please help me. This truck should be in the 14's with my mods and tune. Thanks Jared

 

Anyone please

 

I think you need to get your fueling nailed down first and then you can work on the timing a bit. Not much point in running more timing than you can without getting KR. Your friend might be trying to run 32* but with 3-4* of KR he is not in effect really using that much since the pcm is pulling timing to keep the engine safe. No one can really say what you might be able to run in your truck as every engine will run a little different. Hence the need for custom tuning.

 

what fuel are you running when you start getting knock? load cells and rpm where knock occours? give us a bit more information.

 

Have you dialed in your PE yet?

 

Do you have your TC unlocked in 3rd @ 100% TPS?

 

I haven't messed with the tc settings. Thats all stock. I have my PE table set a little richer then factory since I have long tube headers. I might have my PE wrong. I get knock retard in second gear from 4200-4800 rpm. I run 91 octane gas. And if I try to lean out the pe table I get more knock retard. I am not sure how to tune for the long tubes and no cats. Please Help I know my truck has more left in it. I am only running 24-25 degrees of timing. I hear a lot of people running like 32-34. Thanks, Jared

 

The factory tunning is usually extra rich for engine longevity, so if you richened it up even more I would bet you are running really rich when in PE. BlackGMC has a good thought, I believe the factory settings might allow the TC to be locked in the upper 3rd gear range and stay locked through the shift which could be giving you KR. You really need a wideband to due any kind of WOT/PE fuel tuning, otherwise you are just guessing.