[Leadfoot]

I am no longer the tech official for our club, but people seem to come to me for advice. I know how I "feel" about the issue but wondered how most interpret the following rules.
Aftermarket intakes are allowed
Must use factory Head

A gentleman who is "building" a 2.5 truck asked if machining the intake off of his Cummin's would be acceptable. I told him I would discuss it, meet with our tech guys, and give him a ruling within the next week so he can proceed with his build. He did not want to spend time/money and then be told he can't pull.

He feels that it's still utilizing the factory head for airflow in/out as the valves are unaffected and that he is only changing the intake. Unfortunately on a Cummins (unlike the other brands), they head and intake were cast together as a single unit.

While most think of a diesel intake as pre-turbo, there are Duramax guys who are altering their "Y bridge" which is post I/C and where air enters the two sides of the motor. He feels if Duramax guys are allowed to change the "Y bridge" to a custom larger diameter unit, he should be able to do the same to his "intake".

He also states all 3 makes allow porting, polishing, large valves, different valve springs, cams, etc. so even the factory heads are being "massaged".

Thoughts?

I did a search and found guys who had done it, but nothing as to legality per rules (unless I missed it, and if I did, I apologize).