JohnnieMo

Just a summary of my engine:

Stock heads / bottom end. Added a Vortech kit and exhaust. Car was running around 495rwhp and pulling strong right up until 6200 RPM.

I kissed the pistons on the valves and bent them all. So I decided to upgrade everything to prevent this again. All valves were replaced with stockers and given a 5 angle valve job. A Comp Cam valve train kit was added with new springs, retainers, pushrods, and a competition LS1 roller lifters. Pistons were buffed up, but are still fine.

Now the car revs to 6600, but I hit my peak at 6000 (around 485rwhp) and then it SERIOUSLY drops off by about 50HP all the way to 6600 RPM. So I've gained nothing up top. A/F is still perfect and the car "feels" just fine. Is this just an artefact of the dynojet?? Is there something I am missing here? The blower pulley is stock and I can't see anything else that would affect power output like this.

Thoughts?

SlickVert

iTrader: (5)

I have heard that a lot of after market valve jobs lose flow # and power.
Hope that is not your case.
Did you do a before and after flow test.

oange ss

iTrader: (50)

not likely in his situation

1CAMWNDR

iTrader: (21)

If you have the stock cam as it appears you have, the 10 hp loss is probably the much stiffer new springs vs. your worn stock springs.

JohnnieMo

Its not so much the 10HP loss I'm worried about - as that seems to vary depending on the day and the dyno. I'm more concerned with the 50HP drop past 6k.

No they weren't flowed before and after. In fact the heads were only cleaned up and nothing else.