[Rev]

I shift my 306 at 6000 every time I race it. If you want it to appear stock, you can still put a 302 crank in that 289 block (may have to relieve a little at the bottom of the cylinders for clearance). I do use a hydraulic flat tappet cam (Comp Cams 268 Extreme Energy, 224/230 at .050). I like the Edelbrock RPM Air Gap dual plane manifold. You will need more than the 390CFM carb. I use a 625 BG Road demon ( I did have to do some work on it to make it work well with that cam and intake though). Make sure you get a good machining job on the block and try to get a 0 deck height. I use flat top TRW forged pistons with the stock 302 rods and after market rod bolts (Pioneer or ARP may be better) and it makes a pump gas friendly 9.5/1 CR. Use a good aftermarket electronic ignition system (MSD is best IMHO) for consistent ignition good up to at least that 6000 rpm. You will want a good aluminum after market water pump (Edelbrock?) to cool those extra horses. Use a good 4 row brass or aluminum radiator. I use 2 electric fans as well, pusher and puller for adequate cooling.

You can keep the original heads and have a lot of expensive machine work done for not enough gain. A better idea is to use after market aluminum heads like TFTW or AFR. If you want it to appear fairly stock, you can paint the heads, intake, water pump and no one will probably know.

Also, put in a windage tray, crank scraper( I use Canton), and use under drive pulleys (March?). I think that will get you to maybe 250-280 rear wheel hp on a DynoJet or 350 at the flywheel. You will need to do a little more on the drive train. The 280/1 won't get it. You'll need at least 325/1 with a good limited slip unit (I use an Auburn Pro in my 8"). Also get a 3000 rpm stall convertor (I use a TCI Street Fighter). High performance clutches and bands are a good idea also for the C-4. You said you already have a shift kit.

Headers/exhaust, I almost forgot one of the most important things. I use Tri-Y's made by Patriot. Get them ceramic coated if you can. They're good to 6000 (that's what Shelby used). Run that into an aluminized 2 1/2" exhaust system and use high flow/low restriction mufflers (I like 3 chamber Flowmasters).

Not saying I know more than anyone else or even as much. Hit the link in my sig to see what all I did. Happy to answer any questions that I can. Good luck with your project.

Rev
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