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Original Message
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| Yes there is.... |
| By kevin - 11/03/2002 4:40:28 PM; IP 209.240.198.62 |
| if you are able to use them with your body style and exhaust. They offer a 15 ft lb increase in torque over std cast chamber heads of the era (but some of that was a half point difference in the compression ratio too on the egines that came with them). The intake port is gonna require you use a manifold that has the lip that extends down farther than a Medium riser, (same as any other Low-Riser design), but they can have the floors filled with port epoxy if not. The head gasket design is the older "D" style to fit perfectly (old beaded steel #1154 Fitzgerald, sold by various companies, (and used by Ford) but you can use others, just be aware that the sharp corners can leak with a fire ring that is not large enough. When I mill them .015, they are usually about 69-69.5 cc's with C-J valves installed. The real gain can be two fold depending on application. With a flat valve, you can get a radiused seat ring from careful porting similar to the Hi-Riser for great mid lift flow for torque, plus a hi seat that helps negate any need for spring shims to make up for sunk seats. If you choose that route, and dont want to spring for machined seats, (pun intended) you can use the VSI #503 (I think) "lipped" shim (which fits perfectly on any Ford head that has not had the inner lip machined away for steel seats). The only concern then, is the guide to retainer clearance must be carefully checked to assure there is enough clearance for the lift of the cam used. With a tuliped 2.19 MR intake, you can port it for higher rpm's, but need to notch the top of the block for the most gains. This head has more meat at the outer edge of the intake seat, allowing for the large valve with more seat angle options than all the other std heads before running into spark plug notch cosiderations. With the tuliped MR intake, (107 grams) and the 1.65 tuliped SCJ race lightweight exhaust (79 grams) and no milling, they are about 75 cc's total. Be sure and resurface the exhaust at an angle to keep as much area around the dowel as possible to help keep from getting it too thin there, as these are the only FE head without the support rib on the top of the ear, and they can warp more than the others consequently (plus they are 45 years old). They offer a less detonation prone chamber being smooth too, and have less flame front propagation issues with a dome such as the TRW pop ups for the 390 (1/4") or the lower 428 versions (1/8"). My favorite non 427 head, and capable of impressive power gains with serious porting. Ihope this thred can be pulled up on the search, as I have typed it a couple times before, (whew). |
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