Why do my dyno #'s seem low

[383STROKER]

I know many people putting out more power than me with less of everything, what gives? I have a dyno vid in the vid pic section, my best pull was 475rwhp and 458rwtq. I expected to get at least 500rwhp. My combo is a 351 bored-stroked to a 383 running about 9:1 compression. World windsor Sr. aluminums stock except for gasket matching. comp cam 285int 287ex .571int .585ex 115lsa roller lifters 1.6 roller rockers trick flow box r intake 80 mm holley tb 50lb injectors we maxed them out and air fuel went to about 12.8. at 6000rpm. I have a procharger D1 making around 19 psi. Now I suspect the culpret might be my aod with the GER 3200 stall. Any input on GER stall converters? I also have 3.73 gears. I leave the line at 3800 rpm and have run 10.50 at 127mph with 1.53 60' time.

[frdfandc]

GER just plain sucks. Get yourself a precision industries converter. They are pretty much the best in the business. (www.converter.com)

Also, how is the condition of the AOD? stock original, stock rebuild, performance rebuild?

[383STROKER]

The aod is in good condition I rebuilt it about 10 passes and 400 miles ago. It has a lentec valvebody with transbrake and OD delete. Alto reds and kolene steels, extra clutches. {A} OD servo and a couple other things. Do you think I'd see a HP difference with just a converter change? How about those heads, what if I went to some victor JR's? They would raise my compression though, I have 64cc chambers now.

[RdRunnr]

GER is garbage. If your converter is 3200 stall, how are you leaving the line at 3800? Something is not right with that converter. You are supposed to leave at 500-700 under stall on the two step.

[383STROKER]

That is what I have the digital 6 plus set at and thats where I leave. It seems to work?

This is interesting and kind of what I thought, I have a non lockup converter.
Also the dyno guy said I probably have anywhere from a 18-28% loss from the motor to the wheels, blaming the aod and converter.

http://www.converter.com/whatsnew_dynamometer.htm

What is the formula for HP based on a quarter mile run?
heres one I found

http://www.speedworldmotorplex.com/calc.htm