Do you think I would gain any MPH?

Not unless you are already over 80 mph.

Right now 72 on GPS. So you think I would get no gain?

I don't think you would see any gain at all at that speed. You would be better off putting the time and money elsewhere in the boat. Good exhaust would net the best bang for the buck, but that, too depends on what you currently have.

I have the first 465 Merc recing 502 block, it has polished exhaust tubes. What else would help me see more speed? I just ordered and will put on tomorrow labbed 24P Bravo 1's from BBlades. I was told since the drives are lower on the older boats that nose cones would help but I guess not.

Thanks