How much power can I make?

Are you considering centrifugal or positive displacement (roots/eaton)??

I would think you should be able to do wonders with a 12 pound centrifugal. Nearly double your power.

What's the current CR?

U.M.

cobra_fanatic said:

Yeah I'm wanting to go the centrifugal route. And as far as my CR I'm not sure. Everything is stock except the pistons are a 16cc dish. All other measurements would be stock but I'm not sure what they are. And I have the B heads. I was *hoping* I could run 12-20 psi.

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I think there are other questions here too, as in what do want the car to do? Having the biggest BHP numbers will cost loads, probably be unreliably, certainly not very usable on the road and not nesecarily the fastest at the track either.

If its just massive bhp and track use maybe consider a different engine altogether, as you are limited by cc and general design of the engine.

If you want big usable power then a twin screw blower would be your best bet, lower peak numbers than a centrifugal but more power more of the time.

A Turbo setup would be cool, but very pricy and the comp ratio you have (not sure what it is exactly) is still WAY too high for really high boost from a turbo, the downside is if you lower the CR further you can add more boost, which should equal more power, but it also means when you are off boost you have no power at all, a higher CR will mean less boost and potentially less peak power, but it should have more go when in low/off boost situations.

Have a look here Kenne Bell twin screw , do remember as your CR is lower you will not have as much power now so your increase will not produce the same numbers either (the % increase should remain though). With a slightly lower CR you should be able to run a little more boost and be as safe and produce the same or more power.

Here is a good article from MM&FF they built a high CR and low CR 4.6 mod and bench makred them as n/a and with a supercharger. They ran exactly the same spec on each except for the CR. The low CR unit produced around 10% less power, it would have been nice to see if they could have gotten more from it by raisng the boost. MM&FF article

Having had both, I can now say I prefer the PD blowers over centrifugal for street use. They offer better tuneability and that kick in the butt instant throttle response which is fun from light to light.

300bhp is right. You have to decide what you want to do first and build the car accordingly. A 300hp car can beat a 400hp car with the right chassis and drivetrain mods.

If your main goal is just feeling fastest again, then positive disp. is the way to go. I would't worry about your comp. ratio being too low, the lower your static ratio, the more boost you can add before detonation. If you put 5 to 8 psi into your motor, it will fry the tires anytime you want, and the other gut better be driving something pretty exotic or you will leave him coughing in a cloud of tire smoke. Also those boost levels will give you the reliability you are looking for.