24* at 12.8 AFR
TR6 plugs .035 gap for 75 dry shot
93 octane stock compression

 

The guy who does my tuning for me says it's also important to mention what type of exhaust system you're running, because he finds he can add more timing on the car when it's got a good set of headers and exhaust on it. The better exhaust scavenging allows him to add more timing.

 

Best case is 28* and I've seen it as low as 16* on hot days. AFR is 13.0 and plug gap is .045. 93 octane here.

 

23.5* 12.2AFR peak TQ
22.5* 12.4AFR peak HP

 

Why is the total timing so much less than the older small and BB engines that both made best power at around 36-38 degrees total? Was the higher 100+ octane fuel that much slower in burning that it justified an earlier starting point?

Chuck

 

29 to 30 degress at WOT 13.0 AFR with 93 octane!

 

When the car was tuned I was at 28* total with 13.0 AFR n/a
Then drops to 18* total on the giggle gas, not sure of what AFR havent sprayed yet.

Now im not sure what my AFR is but it reaks of gas bad. I think I need a retune

 

I just got a new ECM so I got my dyno tuning redone again (we decided not to use the existing program, but instead to start fresh)

The stock program was too agressive, it was set to 28-29 degrees and I was getting 7 degrees of knock retard with 91 octane fuel (even with the dyno room being only 40F!)

So we settled on 26 degrees in the end, with no knock retard (this was helped out by the fact that he reset the knock sensor refresh rate to be faster)

My air fuel ratio is roughly in the 13.0 to 13.1 range, although that will lean out more in real world conditions since my car has a Vararam on it so the engine gets fed more air while moving than it does on the dyno.

My car is completely stock except for the Vararam. I'm running NGK TR55 plugs gapped at .050. It made 298rwhp uncorrected. (we picked up 8rwhp over the stock tune and 15 foot pounds of torque in the midrange)

 

I'm at 26.5 with an AFR of 13.0-.2
Plugs are TR55 gapped at .050
10.7:1 running 93 octane

Tried more timing but it didn't increase power. Backed it down and 24 lost power. So I went for the middle and seems to work fine. Never any KR

 

Are most of you running a flat line of timing?
I see that some of you are running high timing(31), then back it down prior to peak TQ(26), then back up(29).
Have you seen a benefit on the dyno or track, by reducing timing around peck TQ?
Thanks
Bob

 

31* with 87 octane NA 346
10:1 P&P heads LPE2-3 cam,
full-lengths & X-pipe

 

Sometimes its necessary to have the dip in the timing curve there to avoid kr b/c cyinder pressures are highest at peak torque.