Well, our stock-block stroker 331 finally made it to the chassis dyno and we're pleased with the results. It produced 346 hp at 5,900 rpm and 343 lb-ft of torque at 4,700 rpm. This equates to a drivetrain loss of 13 percent-about 57 hp and 72 torque.
This 331 powerplant can be both an excellent bracket engine and a great street engine. That being said, we've got some ideas floating around upstairs, so you just may see it pop up again. We're thinking a set of Twisted Wedge pistons, a bigger cam, more compression, and a little tsst, tsst may be in order. Stay tuned.
On the engine dyno, our Trick...
On the engine dyno, our Trick Flow-equipped 331 produced 396.7 hp and 377.3 lb-ft of torque.
With a little more tuning,...
With a little more tuning, we wouldn't be surprised to see the engine pick up another 3-5 hp with a slightly richer air/fuel ratio at the top end. We also expect peak power to come in a little higher than the 5,900 rpm we saw in this test. Still, we are very happy with the results and can't wait to hit the track.
We ran into an issue with...
We ran into an issue with the 3-inch collectors on the headers and the 2.5-inch exhaust. Mac doesn't offer any sort of midpipe that will neck the exhaust down from 3 to 2.5 inches. To remedy the situation, Latemodel provided us with one of its 2.5-inch H-pipes, and we called up Summit Racing Equipment for a set of tube reducers and these Flowmaster 3-inch to 2.5-inch collector reducers. We then modified the H-pipe to fit our application.