Cam duration and water REVERSION

[WHATA SQUIRT]

I'm building a 496 for my 21' jet boat w/ log manifolds,I've heard of water reversion issues w large camshaft's.This is my first attempt at a boat mtr..Whats the sccop on this problem and how do we avoid this...Thanks for any help... :crossx:

[victorfb]

with a lobe sep. of 112 or higher you should be ok. ive used 110 lobe sep. and have had no problems, but thats getting close.

[Moneypitt]

I'm building a 496 for my 21' jet boat w/ log manifolds,I've heard of water reversion issues w large camshaft's.This is my first attempt at a boat mtr..Whats the sccop on this problem and how do we avoid this...Thanks for any help... :crossx:
Log manifolds? There is no way you will have a water problem, the water doesn't enter the exhaust flow until after the snails and it won't be sucked/climb back to the port from there unless the motor runs backward for awhile, a long while............MP

[wet77]

I'm building a 496 for my 21' jet boat w/ log manifolds,I've heard of water reversion issues w large camshaft's.This is my first attempt at a boat mtr..Whats the sccop on this problem and how do we avoid this...Thanks for any help... :crossx:
Call Duane at HTP, thats what I did and we matched my cam motor and pump for the best fit.
First season out I was in the 80's and no reversion problems :cool:

[WHATA SQUIRT]

Duane @ HTP? How can I reach him ? any phone #'s or e-mail address

[jkh04200]

I've heard 112 on the lobe seperation. But, I didn't ask when I replaced mine. Mine is 106, I've been running it for 3 years now and no problem. Merc 228 I/O with thru transom exhaust

[wet77]

Duane @ HTP? How can I reach him ? any phone #'s or e-mail address
Sure no problem here is a link to the website.
http://www.hi-techperformance.com/