We’ve got the answers—the Summit Racing tech department tackles your automotive-related conundrums. This week, we’re talking about the merits of O-ring grooved Ford cylinder heads for high-horsepower nitrous applications.
L.M. • Post Falls, ID
Q: I’m building a 5.0L engine for my 1987 Mustang, and I have a question about cylinder heads. In the new engine, I’ll be stepping up from the current 60-horsepower NOS nitrous system to a 150-horsepower system. For sealing reliability with the nitrous system, I chose a set of Trick Flow heads with O-ring grooves and Fel-Pro locking gaskets.
I watch a lot of automotive programs on TV, and I’ve seen a lot of motors built with aluminum heads, but I haven’t seen many using O-ring grooved cylinder heads. So I wonder about the reliability of the seal between my heads and gaskets, and I worry about compression or water leaks when I put the engine together. Should I have gone with the nongrooved heads? Can I have the groove milled out of the heads I have?
Also, I have a Ford Racing E303 cam for the new engine. I’ve read that the “E” cams are a perfect match for the Trick Flow heads. Is this true?
A: There’s no need to second guess your choices. Fords have half the number of head bolts as Chevys, which is why the O-ring groove is offered for the Ford applications and is recommended to handle higher cylinder pressures from add-ons like high-horsepower nitrous systems. You’ll be just fine using that 150-horsepower nitrous system with your combo—no need to mill out that groove!
The main thing to remember with any cylinder head is to use a good head bolt with moly lube on both sides of the washers.
Trick Flow heads are designed to work well with a number of cams, so that “E” cam should make you pretty happy!