1993GMCPU

It's not just compression here, it's valve sizes/type if I go to a Streetflow type 2.02-1.60 as chip was based on, better chambers listed as enhanced flow verses stock or go to Shavers web site and look at them or Pro Topline. Going from 8.37:1 to 9.40:1, better flow more compression more cam it should be able to deal with etc etc.

It's below stock now and going up one compression point, so not only should there be more HP, MAP should have better vaccum with comp cam. This is a 4 bolt main, bored 40 with HYP pistons that we got for a 64-67 cc head and got a 76 cc head. IF it was going from 67-64, I would agree more, but with it running bad and low compression, it should run right and pickup HP as I found heads, cam, fuel is where I got HP in past as long as you can set timing etc. Chip has more advance and getting fuel, but wrong set up with heads, well it's NOT right! Not sure, but I tried to explain writing is not the same as talking and showing how carboned up motor got, rich etc. 9000 miles only and just trying to find out if there are any big issues in changing head years.

Ronny

iTrader: (1)

have you data logged?

1993GMCPU

NOT sure what that is, so I will say no!@

Dewey316

that made absolutly no sense? was there a question there? with FI, anytime you change the flow ability of the engine, you have to change the computers programing to match.

Ronny

iTrader: (1)

yea i think you need to give us a little more info on what the engine is all about and the mods you are doing. and ask a few more Q's with more specificity? data logging is reading the aldl data stream with a tool as in winaldl or others. tells you about the condition of tune and what the ecu is trying to correct and what it would like to correct but may not be able to correct. only after determining what needs to be tuned does one tune the eprom and hope for a better state of tune as result. that requires a tuning program such as tunercat which is what i use. you threw out a few ideas but i was very confused.