Big problem with my power dyno numbers
 

Ok, I went to the dyno tuning session today and here is my problem, and here are my numbers. At the wheels I got 350ft pounds and 340hp. I spent 20k on Frank's advice on this supercharger setup and at 9 pounds of boost I gained 0 horsepower over what a stock zz430 would make. This too me is VERY unacceptable. The numbers as far as timing and air to fuel is perfect now, but these numbers are not nearly what they should be. I drove the car today, and it didn’t really feel any faster then my straight zz430 setup. What the hell do you guys think the problem might be? Can you tell I'm pissed?

Is the motor actually seeing any boost?

Yes, 9 pounds in the carb hat.

I'd be talking to the guy that built the motor. You've got something wrong there.

The engine was built by Campbell Auto Restoration. What do you think the problem might be? I was told that since the air inlet on the supercharger is close to the headers and that there is no intercooler, that we should pick up a bunch of HP, but that they said that doesn't explain the large amount of loss.

It could be a number of things.

Just for kicks why don't you try disconnecting the blower and see how it runs? I have a p1sc procharger on a 350. I havent dynoed it yet but Im sure im in the 450-500 range. What was your afr at? Timing?

you don't measure boost in the carb hat; you need to measure it in the intake, somewhere after the carb blades. My guess is you're not running anywhere near that boost level, at which point you'll need to figure out why.

A couple questions. What size air cleaner? Is it mounted directly to the blower or does it have some sort of intake tube? What pulley size? What blower? What timing at WOT? What A/F at WOT?

Don't panic yet, once we get it sorted out you'll be very happy with your choice.

Jody

So it's getting air. Was it getting fuel? Were you monitoring A/F ratio? BSFC's? Post some numbers. Did you purchase a specialized blow thru carb?

Blow thru carb engines are among some of the hardest to tune as they violate the very principle that carburetors are based on: Signal. By signal, the engine sucks or pulls on the carburetor to draw air and fuel during the intake stroke. With a blow thru system, you are pushing instead of pulling. Be patient. Collect and analyze data on available air and fuel across the pull. Contact ProCharger and your custom carb builder to analyze the data. If you don't have a custom carb builder, get one. And get to know him on a first name basis.

Are you on the stock internals? 9 pounds of boost with no intercooler could wreak your day.

I'm sure you will get this figured out. :thumbsup: