If you can keep it cool, (and that's a big IF) your 400 smallblock will out-torque a 350. The 400 has a 3 3/4" stroke, as opposed to the 350's 3.48" stroke. It also has a 4 1/8" bore, bigger than the 350's 4" bore. Be sure to use the biggest radiator that will fit, and keep it clean. A 7-blade flex fan and a good shroud should be included, and if you're running an automatic transmission, use a big cooler on it, also. The 400's worst enemy is heat that cracks cylinder heads and causes pistons to tighten up and score.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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