In another thread, it was suggested that we do a cylinder head shootout. This would be what shop does the best port work under certain limitations for the Raptor.
Although I am not in the business, I am up for the task.

I suggested that we send the heads to a shop that is known for building quality automobile race motors. I have contacted a couple of shops and found one that is willing to test up to 6 heads for $50 each. The shop will sign a declaration that all tests were performed equally and that the shop confirmed that each head did not exceed the limitations of the shootout. I am willing to toss in the first $150 towards testing and provide one of my mild heads.

Soooooo, go talk to your "top" Raptor builder -- Powroll, CT, 4 Stroke Tech, Sparks, Trinity, Alba, ???? Get them to participate!!! This is where the power is made in the Raptor. Anyone can install pistons, cams, etc. If you want a real performance engine that will run daily and be within a reasonable budget, this is where you need to be.

The guideline would be a head intended for use on a day to day multi-purpose machine. No Ti valves or springs, stock diameter valve stems only (guide mods are ok), 105mm limit on intended bore, decked and modified chamber are allowed, valve lift limitation is .470" (head must be set up to accept springs and at least one intake and exhaust spring must be supplied to confirm that your lift fits within your spring limitations). All heads will be tested with a clay radius on the intake manifold edge (no intake boots allowed and no exhaust hardware whatsoever. Welding on exhaust and intake is prohibited; however, epoxy and other bonding materials intended for actual use in a working atv will be allowed on the intake tract. All heads will be tested at 28" of water with readings at .005, .010, .015, .020. .025, .035, .050, .100, .150, .200, .250, .275, .285, .295, .300, .310, .320, .330, and .340. Beyond .340" lift, it will be tested at .010" increments until the head craps out. Year 2000-2001 castings only NOT the redesigned core head currently in production. The results for each head will be made into a graph showing flow at the corresponding lifts. The retail cost of all work performed on the head shall be limited to $600 -- as if the head was offered for sale to the general public.

At the conclusion of the test, each participant will be given his flow results and I will be given a copy of a proposed article and photos for inclusion in Dirt Wheels or some other dirt rag. Each participant will be given the opportunity include his/her own comments with the article.

Following this shootout, it would be nice to see a shootout between shops that modify the stock CV carbs.

 

You said there is a re designed head in production currently?? What are the differences? Is there a performance advantage to one or the other??

 

I am still trying to compare. I am told that here are some updates to the casting but that in stock form, the performance is the same.

 

Come on people. Bring this "shootout" to your favorite engine builder!!!