I posted a couple of weeks ago about using a LT4 KM with my new motor and running my NX 150 shot. Some guys said don't do it and some said it would be ok. Well...I'm in the tuning stage right now and trying get the car to run good and everything seems fine except it feels like the computer is pulling way to much timing like 15 to 20 degrees! When I had the PCM reprogramed for my new motor they told me to use the LT4 KM for proper operation because of the roller rockers, headers ec... Well I didn't because I was worried about detonating on spray. I'm sure its the timing because its popping through the intake and the car feels very sluggish, the more as I get into the throttle. I decided that tomarow I'm going to get the LT4 KM and see if that makes any change. Anyone have any other ideas?

 

colder plugs, retard timing, race gas...........

 

colder plugs, retard timing, race gas...........

 

I am running Colder plugs NGK TR6 4177 and I'm not to keen on filling my car up with race Gas every day (expensive) Anyway I put the new LT4 KM in and the car runs alot better. So...I think that fixed the problem. Now, I just have to wait and let the motor really break in before I start doing full throttle runs.