The 250 was factory rated at about 155 hp. With the addition of simple bolt on parts, 4 bbl intake and headers expect about 175 hp. Put in a small performance cam and get about 200hp. Perform headwork, Bigger valves, porting, bolt in lumps and get about225-230hp. Put in a big cam and you will see 275-300 hp.

No "194" high compression heads for me. They will not work well with larger valves( shrouded valves)

I am about to dyno a 250 with just these kinds of parts to test performance gains. It all starts this weekend. Tom

Last edited by tlowe #1716; 03/31/10 12:20 AM. Reason: Giving a newby the proven truth
Inliner Member 1716
65 Chevelle Wagon and 41 Hudson Pickup
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