Hi. I have an 1995 LT1 that I installed a complete LT4 kit into (Heads, Hot-Cam, Intake, Headers, 1.6 Rockers) My issue involves the tune. I had it professionally dyno tuned. While they did not give me an HP amount it feels wierd to me. I did not hook up EGR since the LT4's didn't need it and it sniffs clean here in California. I downloaded the tune that the dyno people put in and the timing is very VERY retarded in comparison to the LT1 tune that was there before. Anyone have this basic combo with a tune so that I can do a comparison between what works for you guys and what I have. Thanks again. Any help would be appreciated.

95 LT1, LT4 heads, LT4 intake, LT4 Hot Cam, 1.6 roller rockers, descreened and ported MAF, 54mm intake, 30# injectors, Shorty Headers, Dual exhaust (2.5") w/ 2 Cat's (Flowmonster 500cfm ea) into Dynomax Welded 2x2.5" to 3" to tip, 3.5" Cold air intake.

Also open to any Commentary on the matter.

 

How much timing is in it? My car had 38 degrees in it after I got it dyno tuned IIRC, down from 43 that pcmforless put in it. And go back there and demand a printout of the dyno runs.

 

I will check. Where was your 38 or 43 at? RPM/MAP reading??? Thanks