It’s the little things that add up and in this case, we’re talking about port matching the intake manifold to a pair of cylinder heads. If you recall, we recently put together a potent, Dart-based, 434ci small-block (“The Bigger Mouse,” Mar. ’12). The whole point of this build was to showcase how a well-thought-out combination could produce big-block–like torque and be perfectly streetable with a thirst for cheap petrol.
During the initial assembly, we left all of the components in its out-of-the-box configuration and decided not to port match the single-plane manifold to the Dart Pro 1 CNC-ported 227 cylinder heads. Was it detrimental to performance? Given the 542 lb-ft and 552hp results, it’s safe to say no and our big-inch Mouse performed rather admirably.
This time around, we wanted to apply all the finishing touches to help create a more efficient powerplant. First, let’s be honest and squash any potential debates; port matching will not give you a significant gain in horsepower.
Think of it this way; smoothing the air transition from the intake to the cylinder heads offers consistent airspeed and flow. The smaller the runner the faster the air, however, when it hits the larger port, it tends to slow down the airspeed and can ruin the fuel mixture. This can also cause potential tuning issues and more importantly, a lack of peak horsepower.
Again, we’re not talking huge gains, but it all helps to maximize your combination. If you have the tools, this is something that can be handled in the garage. If you prefer to farm out the work, then expect to shell out $150 to get the job done with a competent machinist. Follow along as Rocco Acerrio of A.R.E. Performance & Machine shows the ins and outs of port matching.