It probably is putting out more than 266rwhp since they only ran it to 4800 rpm's. I'de go back and tell them to run it to 5800 or demand your money back.

 

Wow.... they didn't even run a full dyno. Don't take your car there again. Your redline is 5800... why wouldn't they take it as close as possible!?

 

Was wondering that myself. With bolt-ons you gain top-end, so I'm sure If they took to 5,800 RPM's you'd see maybe 27_, or 28_ something.

 

What kind of pull is that?

 

lol, yeah that's messed up. Maybe the person(s) running the dyno stopped when they saw the dip?

Or they could have been like the guy that dyno'd my car. He asked me what I wanted to run it up to, I told him 6000. Later after he dyno'd my car and saw the graph and the numbers, he said... "when you told me you wanted me to take it to 6000, I was like because I was thinking more like 5200 but it surprised me!"

Some people seem to think that "LT1 = L98 power band".

 

Ya, that HP is definitely still going up. I also would demand a re-dyno. I dynoed 296/327 with mac shorties and full exhaust (6 speed though). I was running 13.7@102 with those mods, so dont expect much better than 13.5s (I would say).

 

Based on all of the above, I don't think you have anything to worry about. You should definitely get a mail-order tune, though. 12.01:1 is pretty rich!

 

So leaning it up will give me more horsepower? I thought more fuel more = horsepower to a certain extent. Pls I would have thought it would have been lean from the factory for emissions.

 

No car in the world comes lean from the factory. Lean burns up cylinders.

Most cars, from the factory, are tuned just a touch on the rich side for safety. If you tune a completely stock car, you can often get a horsepower or two out of it by leaning it out just a touch.

In general, you want your air-fuel ratio at WOT to be around 13.0-13.5:1. This is where you're making the most power without putting your engine in danger. Your dyno graph shows 12:1, which means there's too much fuel. Leaning it out will make more power.

 

Like what JakeRobb said, there is a balance where the air:fuel ratio makes optimal power.

 

Back to the dyno chart. On my motorcycle's I've had dyno'd you usually see the horsepower climbing and crossing the torque as it falls closer to redline, so it's looks like they definitley stopped running the car too soon. Maybe 10 horsepower more in there. I'm going to call them and see if they will rerun my car. I spend alot of money there and will be spending more so they should do it.