mydreamvette

Hello All,

Added AFE LT headers (with cats), Corsa Extremes cat back,AFE intake and tune....car showing 355 HP now. I am new to Dyno charts....can you tell if this is at the crank or rear wheel and does this seem like decent gains for those mods?

By the way, 2004 convertible, car has just at 16K original miles and runs really strong now, I can definitely feel the difference in smoothness and torque. Changed plugs and wires as well. I don't think I will do anything else, in my mind, these are the mods I do on every Harley I have ever bought (considered Stage 1 in the Harley world) and is the minimum to correct for factory emissions settings etc.

Thanks.

ZigZag

That things a freak, leave it alone.

Andrew

If it is a manual, normal results at the rear wheels. If that is an auto, really, really good results. What R&P is in it? Also, what kind of Dyno?

Do not get hung up on Dyno results. They can be manipulated to read high or low. The key is looking at the graph from the same dyno and same settings before and after the work.

mydreamvette

Andrew

Sorry, ring and pinion (rear ratio). Good results and more importantly, great torque curve.

91LSMAN

Dyno numbers are at the rear wheels. That seems like a fine number for the modifications. Was probably at 305-320 to the wheels before the modifications.

Fastbird

Chassis Dyno's give you RWHP/TQ numbers. Those look good for the car/mods......curious if they're in SAE or STD though because that could make a marginal difference.

bikeriderga

Very good numbers for a stock Vert with just those mods.

That puts you close to stock Z06 numbers.

Vetteman Jack

Nice numbers from your car and the mods.

Gordy M

If those numbers are accurate, you have as much hp as a stock Z06 which usually dyno 355-365 hp on any given day. That means you should run about 12.3-12.7 in the quarter mile. Take it to a drag strip and check it out, if you run low 13's then you know they were blowing smoke. If they are accurate then the car has had a cam change done prior to your purchase.

Headers and a tune should net you about 20-25hp at the wheels, the intake still uses heated engine bay air and will give you about 2-3 true hp at the most. The true test of hp gains comes at the drag strip. If the conditions are the same then the times should be consistently better with the changes. Also the trap speed will show the true improvement. HTH

A well known GM performance engineer had his 17 Z51 Corvette at a large Corvette event and a performance vendor asked to to let them dyno it. It came out in the 510HP neighborhood--the engine was bone stock and usually dyno's 100 hp lower.