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Sun Jul 27, 2014 7:48 pm

I and my tuner are at odds on timing advance. I need some input if there are folks with real world timing figures. 10.5 static compression 86B cam on 114 LSA so dynamic compression less. I have a Haltec ECM handling fuel and timing so almost any timing curve is posible. I need some ideas on 1000 RPM initial timing and max total timing and what RPM it should all be in by. If you have a plot or excel sheet with timing plot that would be even better. I think we are too slow on timing the tuner is thinging more like gas timing.

Sun Jul 27, 2014 8:08 pm

Couple more degrees at idle, five to eight more degrees when it all comes in

Sun Jul 27, 2014 8:30 pm

So at 1000 what amout 10 degrees 15 20 not sure where we should be for intial lead. Also when it all comes in are we talking 35 to 40 and by what RPM? Any clarification you can add wouldbe great. Thanks

Sun Jul 27, 2014 8:57 pm

I'm about 10 or so at idle, full advance like normal around 3000rpm, instead of 32 degrees, go to 37-40. Start low and see what your car wants.

Mon Jul 28, 2014 12:15 am

Are you going to be on a dyno? Let the dyno tell you what the engine wants at power. Then get out on the street and let your butt tell you what the engine wants everywhere else. Datalog while you drive.

Mon Jul 28, 2014 4:18 am

Gotta agree with Chip, but you are right the E85 likes the same as the performance Dubs we are used to - a rather rapid advance maxing at 2800-3200. Your compression is probably a little low for E85, so you'll want a bit more initial. Find a point where it isn't gutless off the line but will stilll start OK. With Haltech you can always set your idle a bit higher if need be. (BTW, don't start your advance until 1500-2000, gives you a bit more wiggle room on starting and your engine won't make much at these revs anyway.)