DanielRicany

Hey guys, I have a 1985 Corvette with a Miniram, 58mm Throttle Body, Hedman Longtube 1 5/8" Headers, flat tappet zz409 cam, AFR 195s, 3.75s, and a lot of other small modifications.

Anyway, my Miniram is coming back tomorrow from being ported, and I am going to have to tune the timing tables for the addition of the new heads.

How do I do this? Can anyone link me to a guide to tuning this or explain it?

Also, when someone says they are running lets say 34* of total timing, what do they mean in regards to EST?

I also have an 870 ECU that I'm using right now, if that makes any difference.

I can tune all the other areas pretty decently but I'd like to understand how to go about tuning the timing.

Thanks very much!

RBob

iTrader: (1)

Total timing is usually the spark advance (SA) at WOT. At 34* a timing light will show it on the damper at 34* BTDC.

Other areas of the SA table will be higher then the 34* of total timing. This is the light load and cruise areas.

Other areas are going to be lower then 34*, such as idle and low speed, high load areas.

IIRC, AFR publishes the total timing value for there various heads. That is a good place to start.

It also helps to try various timing tables. Such as the f-body LT1 spark advance tables, and the y-body ARAP table. See which ones work the best.

RBob.