Power loss with new Comp Cam valve train kit
#1
Staging Lane
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Join Date: Apr 2005
Location: Calgary, Alberta
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Power loss with new Comp Cam valve train kit
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?
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?
#5
Staging Lane
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Join Date: Apr 2005
Location: Calgary, Alberta
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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.
No they weren't flowed before and after. In fact the heads were only cleaned up and nothing else.