Skip to main content

Reply to "another 351c build question for strokers, your input is welcome."

John,

To build the stroker you're proposing you need a 4.00" piston with the Cleveland valve relief, a 1.35" nominal compression height and a 0.9272" pin diameter. I browsed the Keith Black, JE & Wiseco web sites looking for such a piston and came up empty handed.

You can achieve your performance goal with the X-celerator intake, so save yourself $500 clams and run what you got, instead of the Funnelweb.

I can't comment on "how much" horsepower would be gained with a pair of 3V's capping your motor in place of the iron Aussie 2v's, but I'm sure there would be a gain (higher intake port, better intake port design, better combustion chamber design, beter spark plug location, better exhaust port design). Speaking in drag racing terms, I've heard guys comment the aluminum 2V heads were worth a half second over the iron heads with no other changes. No comment however about how well the iron heads had been prepped.

Looking over your proposal, 400 rwhp means about 480 fwhp. That's pushing the Aussie 2V's pretty hard. With the bigger valves & intelligent porting they're good for about 500 bhp & 6500 rpm.

Your suggested solid lifter cam specs are in the ballpark for your power goals. The 2V head intake ports hit a wall in port flow at 0.550" valve lift. Some suggested solid lifter flat tappet cams are the Crane F246 or the discontinued Ford Motorsport M-6250-A342.

Selecting a compression ratio is putting the cart before the horse. The camshaft, cylinder head & fuel determines the compression ratio. But I think I know what you're getting at, you're hoping the closed chamber heads allow for more compression ratio than the open chamber heads. The answer is YES as long as you zero deck the block and set up the "squish" properly. And in fact, I'm sure 10.4 comp ratio is in the ballpark for the cam specs you're suggesting.

To make the power you desire you will need the piston rings to seal very well and port work on the heads; and to survive the rpm you want to run you will need oil system mods, crank prep, good fordged rods with dowled caps and sturdy cap screws, a main cap girdle, a good balancer, sturdy valve train (no oem valves, keepers, locks).

By the way, sounds like you have as many Cleveland parts laying in your garage as I do!

Your friend on the DTBB, George
×
×
×
×