Few cylinder heads have hit the small-block Chevy world with as much impact as the GM Performance Parts Vortec iron cylinder head. By now you already know that the Vortec head offers outstanding intake and exhaust flow combined with an incredible price of under $450 for a complete pair ready to bolt on.
Unfortunately, this cylinder head also brings with it a couple of limitations. First and most importantly, the heads require a specific Vortec intake bolt pattern that differs from all previous small-block Chevy intake patterns. While the Vortec heads can be re-drilled for the earlier small-block bolt pattern, its not recommended.
One of the many applications where the iron Vortec head would be a natural is bolted on a third-generation Camaro or Firebird Tuned Port Injection (TPI) engine. Both the 305ci and 350ci TPI engines used iron cylinder heads, and the Vortec would be a perfect swap. Unfortunately, the Vortecs different intake manifold bolt pattern made this swap unrealistic.
Scoggin-Dickey Performance Center in Lubbock, Texas, recognized this opportunity and has just completed a TPI manifold base that employs the Vortec cylinder-head bolt pattern. The manifold base uses larger intake runners to take advantage of the Vortecs excellent intake port flow. The manifold is designed to accept either stock TPI runners or the larger, high-performance runners available from several companies >> like ACCEL, Edelbrock, Lingenfelter Performance Engineering, TPIS, SLP, and others. These can be used with the stock TPI plenum as well as a stock or large-bore throttle body.
Third-generation Camaros and Firebirds also have emissions legality requirements. The iron Vortec head does not include an exhaust-gas crossover passage, which was incorporated into the third-gen 305ci and 350ci TPI heads. This exhaust crossover port is where the exhaust gas recirculation (EGR) valve picks up exhaust to direct back into the intake. In order for Vortec heads to be legal in a third-generation Camaro, Scoggin-Dickey includes an external exhaust-gas pickup tube that directs the exhaust gas from the passenger-side exhaust header into the intake manifold.
This manifold is not just intended for use on third-gen Camaros however. Theres a whole world of opportunities waiting for the chance to pop a TPI-style intake on a hopped-up small-block with Vortec heads. Scoggin-Dickey also sent us several dyno-tests that reveal excellent torque numbers of over 425 lb-ft at 3,800 rpm and a respectable 354 hp at a very low 4,800. This is a function of the runner length of the manifold that keeps the peak horsepower numbers below 5,000 rpm. While not optimal, this makes for an outstanding grunt motor with tons of torque.
If youre looking for a bit more horsepower, you could also step up to the John Lingenfelterdesigned ACCEL SuperRam intake. The SuperRam runners are shorter than the TPI runners to increase top-end horsepower while sacrificing little power below peak torque. Weve had excellent results with this manifold, and on a 420ci small-block, weve made as much as 525 hp and 540 lb-ft of torque with this intake.
There are a ton of opportunities to combine the excellent dollar-per-horsepower advantages of the iron Vortec heads with this new Scoggin-Dickey Vortec TPI manifold. Whether you want to hop up your third-gen Camaro or just want a slick tip on EFI for your early Chevelle or Camaro, the new Scoggin-Dickey Vortec TPI manifold may be the right part at the right time.