Ok here is some info.. As well spoke to my builder and he found an early dyno sheet which will be the most relevant to you all.. as this is on a stock bottom end, and at this point has no tuning just factory computer..
This is on a Mustang dyno.. You pull this same pull on a dyno jet and you will be another 30/40hp Crank higher.. And thats they dyno ppl use for bragging rights, But if you want accurate numbers Mustang is the way to go ..
Anyhow Builder Comments below..
As for your stuff, there is some trick stuff that I did with the heads that worked and I am not in the business to let people know what we worked hard to learn. All potential buyers need to see is your dyno graph
Remember 550+ rwhp on a Mustang dyno is at least 670 hp at the crank for a Viper truck with those heavy wheels and tires etc.
There are Viper trucks with superchargers that don't make that power.
Basically, your heads flow over 300 cfm on the intake with a custom made 2.02 intake valve. Intake manifold is also ported and throttle body is modified.
The heads, manifold and cam are custom designed to work as a system on a Viper truck and intended to make good low speed torque to move the weight.
Remember the 550+ rwhp was without tuning so with tuning you should be in the 570 range and near 690 hp at 5700 rpm. That's almost 200 hp more than the stock engine.
Ok the first sheet is the 2nd page of the 2nd pull on the dyno .. The dyno pull you see here is a few hp short of the 550.. but you can see the results either way... still looking for the other dyno sheet that shows the actual results that show the 551pull.. anyhow this is what i have for now,, will post the other one up soon as i find it
