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Twisted Wedge Two-Valve Heads - Two-Cam Cylinder-Head Jam
Trick Flow Specialties Two-Valve Heads Turn The SOHC Market Upside Down-We Gain 34 RWHP Over Ported Stock Heads.
We left the pulley sizes identical, so the blower delivers the same amount of airflow to the engine. That would give us a true indication of how much more power these heads make over our CNC-ported stock ones. On the dyno, Mike Dezotell of Dez Racing started conservatively by backing the timing down from 17 degrees to 13 degrees. He was concerned with the higher compression and pump gas. A few dyno pulls and the results were 483 rwhp and 439 rwtq.
"It wants more timing," commented Dez as he fiddled away on the SCT program. He gave it just that and set it at the same 17 degrees as our baseline pull. The result was an outstanding 499 rwhp and 462 rwtq, which work out to gains of 34 rwhp and 33 rwtq over our baseline pulls.
Our 499/462 performance was backed up with a near identical 499/461, showing our results weren't bogus. Dez then swapped the program over to one for the Snow kit. He kept the tune identical; we were just increasing timing due to the better octane rating the meth delivers. The same baseline 23 degrees and air/fuel ratio provided us with an additional gain of 15 rwhp and 16 rwtq, for a grand total of 514 rwhp and 477 rwtq.
"That is the most power I have made with a P-1SC supercharged car. Typically, a combo like this with bone stock heads will make 435 rwhp and 465 or so with CNC-ported stock heads. The Trick Flow heads are 60-65 rwhp better than unported stock heads," claimed Dezotell.
Interestingly, the boost remained at 11-12 psi throughout all of the tests, despite the better flowing Twisted Wedge Street/Strip heads. Some might wonder why the boost stayed up, and our best assumption is the increase in compression ratio.
"We are only scratching the surface with these heads. I think larger cams, like the Anderson Ford Motorsport F-72 ones, springs to match, and a better exhaust system will allow us to pull higher rpm levels for even better gains. As we work more with these heads, the more we will know what it likes. I have seven pairs of Trick Flow heads ordered for customers, so we should know soon enough," commented Dez.
For now, simply bolting the Trick Flow Specialties Twisted Wedge Street/Strip Two-Valve heads on top of a mildly supercharged mod motor proved to be worth 34 rwhp. Four-Valve and Three-Valve mod motor combinations are going to have some fast company from its little Two-Valve brother. Let the mod motor games begin!
Flow Bench Notes
- Bore Size: 3.552
- 28 inches of water
- Trick Flow heads feature 1.84/1.45 valves
- Stock Heads feature 1.78/1.45 valves