Reason Im asking is Ill be going to the dyno today with a friend and he brought up that question so now I dunno whether to find optimum timing first or correct the AFR first. It seems like if you got a better burn with optimum timing that the AFR would be different from if you were a couple degrees off.

Has anybody seen a notable rwhp/rwtq improvement adding or retarding more than 3 degrees at WOT anyway?

 

Yes I've seen noticible improvements by subtracting 2* & adding *'s in other areas, my A/F didn't change much if any, hope this helps.

Matt.

 

Yeah, have to experiment and see what the engine wants. Every car is different, heck even given all the same mods I've seen cars want completely different spark and fuel. This is why I won't do mail order tunes, but that's just me. Some engines respond quickly to changes, other take a while to show what they want, trial an error. Error on the safe side, be conservative and careful.

Hope this helps,
-Christian

 

Thats true, one person can have a good port job, good Combustion chamber ie. swirl, will require less timing, & you'll see the A/F changes I guess, but its true about mail order tunes, when you start to know a lot about dyno tunning you start to see how inaccurate a mail order tune can be, on the dyno when I took 1* of timing out I gained 5RWHP, so how can you be so accurate with a mail order? this is consistent, I made 2 runs with 34* of timing & then 35* & gained 5rwhp with 35*, then lost 2rwhp wiht 36*.

should have tried 30* who knows maybe the engine would be even different, I doubt if you lost power giong back you'll keep loosing it, who knows every engine is different as mentioned.