Got questions? 

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 combono 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!

Author: David Fuller

David Fuller is OnAllCylinders' managing editor. During his 20-year career in the auto industry, he has covered a variety of races, shows, and industry events and has authored articles for multiple magazines. He has also partnered with mainstream and trade publications on a wide range of editorial projects. In 2012, he helped establish OnAllCylinders, where he enjoys covering all facets of hot rodding and racing.