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HotRodsbyHazell
08-22-2006, 01:40 PM
I am wanting to build a small block chevy with a procharger and make around 1200 horsepower. I really want to keep the cubic inches to around 360 and the biggest procharger I can run is an F1R. I am planning to race this car in radial tire classes. I understand I will have to have a intercooler and will put the biggest one on the car I possibly can. Any ideas on what cylinder heads? Is this even possible? The car will be driven on the street so I want to have an air to air intercooler and be able to run pump gas am I nuts?

ProdigyCustoms
08-22-2006, 06:16 PM
Yup, your nuts! The F1R will make the wind, but you will have to run a ice box water cooler, and somewhere in the 25LB of boost range, and pump gas is a fantasy. It will have to be a hell of a short block to hold up to the boost. O ringing the block will be required.

blown69nova
08-22-2006, 06:22 PM
Go to turbomustangs.com or nmraforums to find out about blown small blocks ( I know it's not a ford). The renegade class Mustangs run mid 8's with that blower and NO intercooler.
Steve

Blown353
08-22-2006, 09:10 PM
As said, *pure* pump gas, 1200hp, and 360ci ain't gonna happen. Sorry. However it may be achieveable if you run EFI and staged injectors and have the secondary injectors feeding the engine high octane race gas when under boost. That's the only way it's gonna happen IMO.

A no brainer if it was drag-only: Alky! If it's going to be a drag car only the alky will not only make the power but help out BIG TIME with air temps which are going to be high with the CFM and amount of boost you'll be pushing, even with a good air/water IC.

It's definately doable but not on pump gas and it will be an expensive build as you will not be able to cut any corners if you want it to live. One thing to watch for especially at that level is the crank snout-- I would get a custom crank with a BBC snout (and double keyway it) to avoid snout breakage. With that much boost, you may be into cogged belt territory to avoid slippage which imparts odd harmonics on things-- so you may want to consider one of the direct drive gear setups that drives the SC directly off the crank snout.

Even though I run a Procharger myself, at the power level you are talking about and given the considerations and extra cost in making the SC drive reliable trying to spin the SC that fast I'd say you really need to look into turbos instead.

Now, drop your HP requirements and things are different. A friend made 694hp at the rear wheels on 91 octane pump gas with a 406 SBC, non intercooled D1SC with water injection. I'm in the same ballpark myself. I drive the car everywhere.

If you want to run pump gas and turn 1200hp you'll need to up the cubes-- I don't see any other way around it. Either that or go with staged injectors and hi-test when necessary.

HotRodsbyHazell
08-23-2006, 04:46 AM
So is it possible with a big small block? Like a 421 or 434? Also will it help if I step up to an F2? I understand when it is making a ton of boost I will have to run race gas. What I meant to say was I want to be able to change the boost level to run pump gas when driving it and up the boost and dump in the race gas when I go to the track. Will any of these things help?

ProdigyCustoms
08-23-2006, 05:11 AM
Well, cubic inches will help, but are you not limited by class rules? Basic math in laymans terms is you can double your horsepower in a perfect set up supercharger specific engine for every 1 atmosphere, about 14LBS boost. This would be in a engine specifically designed to be supercharged. This does not mean you can put 14lbs on a stock ZZ4 and double the horsepower.

It should be no problem to build a 434 that can make 500NA even at low compression (8.8 : 1 or so is where I would set it). So in theroy, if you are making 500 off the wind, you will need about 1 1/2 atmosphere to make 1200HP, or 21lbs of boost.

Heat is your enemy, and boost is heat, So at 20+ lbs boost, it will take a ton of octane to prevent detonation without intercooling. A air to air, a big one, would probaly be ok for very high octane, and yes you could lower the boost (change pulley) and drive it on the street on pump gas, carefully.

Trying to do this with a 360CI motor, you will probably be lucky to make 400HP NA, so your looking at nearly 30LBS boost.

blown69nova
08-23-2006, 07:17 PM
Did you guys happen to check out the pump gas drags? There were small block cars running close to 8's on pump gas (duh) so I'm sure they had to be around 1200 hp.
Again, check out the small block Fords and see the kind of hp they are making.
Don't get me wrong guys, I don't have 1200 hp experience, it just seems guys are doing it.
Steve

ProdigyCustoms
08-23-2006, 09:18 PM
It does not take 1200HP to run close to 8s. My street racer makes 687HP to the wheels, weighs 3450, and runs bottom nines, very close to 8s. It is a pump gas 404CI SBC nitrous motor. Also, did you see the intercoolers some of those guys had? Water to air will do a lot, especially with a little ice in them