CMI or not to CMI
#1
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From: Topeka, KS USA
The mills are out so the heads can be cleaned up on my 98 38 with Hp500's. Now would be the time to bolt up some CMI's . . . any of you Fountain kids made this leap? If so, do you think it was worth the dosh? They are super shinetastic!!!! Thanks for the input.
#2
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Joined: Jan 2004
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From: Northern NY
Did the "E" tubes on my Velocity on the 525 SCs years back and they were worth the change just for the look, and were good for a little as well. The current one has the 525s and the CMI tubes, just love to polish them up, and just take in the shine!!! We spend a lot of stupid money on these toys, just do it!!! Flitz metal polish is the ticket to a "Shinestastic" smile that just won't go away.
#3
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hi ive got a 27 fever 496 mag ho ive just fitted cmi sport tubes yes they look and sound great massive mid range improvement but dont seem any better wfo th e boat would run 70 both ways before not much fuel and only me on board now with 2 people 125 lts fuel still 70 maybe it needs more pitch at present l/h b1 26 at 5300 on tach the way tey go on about them i expected to se more improvement
#6
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Joined: Jan 2004
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From: Northern NY
hi ive got a 27 fever 496 mag ho ive just fitted cmi sport tubes yes they look and sound great massive mid range improvement but dont seem any better wfo th e boat would run 70 both ways before not much fuel and only me on board now with 2 people 125 lts fuel still 70 maybe it needs more pitch at present l/h b1 26 at 5300 on tach the way tey go on about them i expected to se more improvement
I would try a larger prop. From what I've heard the 496s work better if you load them and turn them closer to 5000 rpm, might see the speed come up a few then.
#8
Just give yor props a little more cup to the leaing edges It might work better that stepping up to next size. The rev limiter is around 5250 rpms on the 496 HO if I remember right.
Good luck!!!
Good luck!!!
#10
I doubt you will pick up any speed, but they sure do look nice. Get the 525 long tube headers if you have the $$$. The tuned length will help some. I would also recommend dry tails for a few extra HP if noise is not an issue in your area.



not to mention the mid-range performance.

