What kind of timing are you guys running? Here's what I have:
99 5.3
212/218 .600/.600 112 lope seperation Texas speed cam
Full length headers
93 octane
I'm only running about 21-22 degrees max. What are you guys running per rpm? What rpm are you getting max timing?
I'm in a much newer truck with VVT all that jazz with a stock cam and can do 23-24 on 89 octane.
With your mods one would think another 4-5 degree's is possible for sure. Keeping an eyes on fueling with a wideband and knock is the key.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
Good to know. But is yours direct injection? If it is then that's to your advantage. I'd imagine you can run a little more timing with direct injection.Originally Posted by 5FDP
Nah, it's not that new. Still a port fuel injection being a 2012, 2014 went to direct injection. Better intake manifold, cylinder heads and VVT do help though.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
Gotcha. I do have the same manifold tho....putting that on next weekend.
My 03 5.3 with stock cam, no cats, and CAI, on 91 octane runs between 23.5 and 27 at full throttle depending on intake air temp.
I agree that your setup can handle several more degrees of timing. In several cases the maximum output is reached quite close to the point where detonation starts...especially when using 87-89 octane in which cases I have been backing away from the detonation only .3 or so degrees on the High Octane table. It is often worth it to go to such lengths.
Last edited by IARLLC; 09-12-2016 at 07:39 AM.
Awesome info. What's your timing down low? 1500, 2000, 2500 etc?
I am running a 2200 RPM stall GM converter so the log does not show exactly where the timing would land at full throttle if solidly loaded down below there. The timing numbers I mention are total timing including AFR/PE additions. 1500=16, 2000=21, 2500=23, up to 26 or so by 3500. You can probably get away with a little more down low with the cam.
Try 24 degrees of total advance from 2500 rpm to 4000 rpm rows, 22 degrees in the 4400 and 4800 rpm full throttle rows (could be anywhere from 0.68 grams to 0.88 grams), 27 degrees at 5200 rpm and 28 degrees from 5600 rpm to redline. Scan for knock retard and see how it goes for you. On 91 octane I made the most power with this combo on an 05 lq4 6.0 with a 226/231 .595/.605 lift cam.
Your peak cylinder pressures are at peak torque so you need less timing in that area as you will see with knock. My peak torque was around 4600 rpm with my stock truck intake and tb with an 85 mm truck maf
Also I found a personal recipe to have my power enrichment at 12.18 afr from 2500 rpm to 4800 rpm, 12.45 afr at 5200 and 12.7 afr from 5600 to redline.
I gained 30 rwhp and 40 rwtrq at 4000 rpm after a retune with a larger air filter and changing the PE afr from 12.7 to 12.18 in the 4000 rpm area despite 18% more humid conditions on the dyno.
Last edited by Matt_lq4; 09-12-2016 at 05:26 PM.
Awesome info. I appreciate it. I'll try it tomorrow night. Thx!
Thx!
Seems to be running a little better now with more timing. I'm at 26 and it's still not pulling timing. The truck can now outrun my v6 accord which is a 13.70-13.80 car. Not too shabby for an old ass 99 5.3 extra cab silverado with the original 180k mile motor still in it. And I have 20" wheels on it that weigh 80lbs each lol.
That is great. Some like even a bit more. Mine uses 26.5 to 27 on top, from just past torque peak to redline.
People say 26-28 is what they like but I have heard of even more. If you are not getting any KR yet, why not try 27 anyway?
I have a 2003 5.3 I'm running 27-29 degrees on 93 octane with an AFR of 12.8-12.9 at WOT
Do you have this tune still available?
Horsepower is like a condom. I'd rather have it and not need it, than need it and not have it.
Disclaimer: I do not know what I'm doing. Follow at your own risk.
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