Tim, here's some of the responses about your combo from guys on speedtalk. Those 540 combos, making 700 plus HP on pump gas, are not running anything remotely close, to a 241/246 camshaft.

Have a number of similar units out and running for some time now.

Dart S/D, 540", RHS 320's, Comp retro-hyd-roller, 9.75:1 C.R., 2527 Edel, and a 4500 Holley. Bolt-together build, absolutely no HP chasing at all!

All off the dyno at/above 730 HP @ 6200 and 700 Torque @ 4500. Have many of these still in service after 15 years or more, not a single problem to date an any!

These are tested without any accessories however.

Thanks, Gary in N.Y.

P.S. With a change to a solid-roller, some very minor head work, and 10.5/10.75:1 C.R., we see above 775 HP/725 Torque, very similar RPM band. The RHS heads flow 375/275 @ .700" from the boxes. Just tested some recent "brand-X" heads we took on for a line, and still see just above 700. The cost on these heads is about 1/2 price!

Here is a few that I have built for power boats. 540-548 bbc's, ported Iron eagle 308 heads, not radical porting, but detail work, chamber work, ex port work, the intake received attention thru the whole runner, about 320cc ish when done. 10:1, the Dart single plane that came on the boat originaly, on the mecruiser HP 500 502, Custom comp hydraulic roller, 252-260 at .050, .640 lift, 112 lobe sep. For numerous reasons. Did like 8-10 of those, either 540's or 548's out of the original 502 blocks. THey would make 715-730 hp, and about the same for tq, peaked about 5800 for hp, in the 4500ish for tq, depending on carbs used. And they rocked. Also built similar engines, but made them 509's, using the stock crank, they would make about 680hp and about 665 for tq, but, I would pull the duration back to 248-256,to keep the same rpm range.They would actualy go 6000-6200 for peak hp, same lobe family, so the lift was the same, and the same 112 lobe sep.

The interesting part, I did a pair of 540's, with basically all the same parts, except, used a set of iron Eagle 345's, instead. The idea was to eliminate any porting. Just blended the valve job top cut into the chamber, and blended the short turns. Those were down a solid 50hp and 50 ft/lbs over the ported 308 heads. Not suprising really, more air flow thru a smaller cross section, just works better in that rpm range. The 345's moved more above .700, but less below. The 345 iron eagle 540's made about the same power as the ported 308 iron eagle 509's. The 540/345 heads still made more tq, but not much.

The motor is crying for more duration and seeing as you already have 1.7 rockers Comp cams HUC lobes intake lobe 13064 and 13066 is what I would use with a 3 piece core ground on a 110lobe sep. The specs are 255 263 680 lift. Another cam I use cause its cheap like $240 from your local gm dealer and you can run melonited distributor gear is gm 572 cam . specs are 0.632-inch lift and 254/264 degrees of duration at 0.050, 112. On the gm cam use PAC-1371 spring it is a lightweight 1.374 dia 172 @ 1.900, 455 @ 1.250 cb is 1.2
In general on hyd rollers to remove weight at the valve I tend to use tool steel retainers and lightweight low mass small diameter springs like PSI CT1225 Dual 1.445 [email protected]" [email protected] 1.1cb or PSI CT1226 Dual 1.460" [email protected]" [email protected]" 1.15cb and above mentioned Pac. I always set .050-.100 from cb. Did the engine builder use a valve spring retainer mounted dial guage to minimize rocker sweep and optimize valve motion and pushrod length?

http://speedtalk.com/forum/viewtopic.php?f=1&t=47746

[QUOTE=offshorexcursion;4506447]Tim stay hydraulic

Unleashed is run harder and longer then any boat participating in this tech section (with videos to prove), and my morel lifters have been flawless :

That's because mine is sitting on the bench in pieces. LOL

I only go to the Playpen and back. That`s what I hear anyway.

Understandable considering your only spinning one prop. Maybe you could have one of your buddies pull you up on plane so you can run the boat a little on one motor. They do tend to have a little lean when running on one...

I like the way you think, actually since I don`t do any real boating, I may just idle around from now on. ^^
I`ll let Kevin and Kris do all the hardcore offshore boating.

Hey Joe you wanna get like a small fishing boat and use it to pull both of us to the Playpen?

Yeah. Calm water raceboat. Don't say anything you *****ed out at boyne when several others went including a 33 power play.

I already stated a few times I am staying HR. That's a huge claim to say yours is ran harder then anyone's here...

Not too full of himself, is he?:

Stay wide open till you see god then brake!

What happened to isky's. Seems like for the longest time they were the chit. This might have been covered covered earlier if so my bad. Just got in. Or did I read a post Johnson is making isky's now? If I did choose to go hyd roller I'd want the very best without question.

Years ago I recall talking to a speed shop downstate and they said there is litterally very few companies that actually build lifters and just build to spec for all the companies. I know this holds true to a certain extent but can't verify what I was told but it makes sense.

Anyway did isky's go down hill? Just curious not making a claim.