NHRA 2020 Rule Amendment SS Intakes???

[Billy Nees]

Originally Posted by BBF67

The new ruling is not in the intake manifold paragraph of the rule book. It is in the cylinder head paragraph. Spacer plates are being used to make up for what is cut off the intake side of the cylinder head. The heads are being cut at a severe angle so the valve cover bolt holes remain intact and runner volumes can meet the spec.

Yes, I know. What I meant was a clarification would be made on intake spacers.

[Jim Wahl]

Originally Posted by Billy Nees

Yes, I know. What I meant was a clarification would be made on intake spacers.

In 1989 at Indy I watched NHRA toss two or three BB Fords for cutting too far into the intake side of the heads in order to get the advantage that would give them. The valve cover screw holes were right next to the edge of the cut. They went out to a junk yard and bought a head and when they were laid side by side it was very obvious what was being done. My point here is this has been being done for a loooong time! Pretty sure this is when extrude honing was becoming popular. Jim


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