Depends Josh. Personally, but you know how I roll, I'd toss the C9's on, a new bumpstick with some hardened pushrods, 1.73 rollers and see what happens. (I think you're fine, depending on cam, just be sure you have enough valve/piston clearance). The compression numbers will rise a little I'm sure, or some will go away rather quickly and violently!

J/K    Don't do it without really following through the entire engine. The front two cylinders being over 10% lower than the rest indicates something, not sure what though. Need my brain werkin on full capacity. But not bad. They're right, leave it be.  Over the winter is the time to do something like this, and consider oversize valves, seats and maybe porting those puppies (What makes them special anyway, is their usefullness in heavy porting, from what I just found out).

Any added pressure on the top end is gonna be felt hardest by the bottom end well before the seat of the pants even gets to enjoy the ride. Always remember that.

Ray

Ralph, Paul, Thank you both, there's a ton of information there for me to process. I think I'm fine with the stock D3VE's on this particular engine and it's purpose, but it is GREAT information, as I have another 460 that I was planning to put in where this one is now going, and now it needs to be "better" than the Moo. Now I know what to look for to do just that. (Without all the aluminum heads, etc, wanna stick with mostly factory parts on this engine build).

Thanks Guys! Didn't want to have to try and find, then go through the expense on the D2OE heads I did on the Moo again! (Seems I didn't need to).

Ray

My GAWD I hope he took one, LMAO, that's some funny sheit right there!

Dude, you made my focking day! And I KNOW it wasn't that easy.........Finding enough fire ants for THREE wekeends in a ROW! 

Ray

Edit; Hold on, Just realized you were from Alabama, so the fire ants and drunk cheering buddies are easy to find, and you prolly chained the boat to a tree and pulled the pump with your 4x4 right? 

J/K dude, really, but still funny. We don't do stereotypes around here........ ........................

Ray

Very Sweet ride there! I like it ALOT! Hope to see it this Summer/Fall.

Ray

Nordie, Keith and Brad are both exactly right. I've been divorced too and am in full agreement with what Keith is implying (went through it 11 years ago, along with the custody battle) and Brad simply just outright said it (Right on Bro!).

She's doing it to get the reaction, and she's winning. It's a form of control, to break you down to a basic emotion (anger), where you're not thinking straight. Don't give her that satisfaction, and she'll stop. Not that she's all that and a bag of chips otherwise, mind you, but obviously she's trying to mould or train you somehow into being what you're not, or just seeing what she can get away with. Wish my replacement cell phone was here! lol (Still lost everyones numbers, so y'uns may need to PM those back to me ASAP). Land line is 520-509-1518 if ya need it Josh. Or anyone else for that matter. Home 'til noon tomorrow.

Keep a chin up and your temper down! And yeah, follow Brads advice, VER-BATIM!, and take the high road, do NOT give her the predicted reaction she is planning on!

Oh, And to answer the Thread topic,

ANYTHING BUT THE LAWN MAINTENANCE I'M DOING RIGHT NOW!!!

Ray

Since we're on the subject, I was wondering Paul. What's the significant difference, if any, from the normal D3VE-A2A heads on nearly every Marine 460 I've seen and the Dove C's?  Any appreciable difference really? I see people really touting the Dove-C's as if they are the Holy Grail of heads, yet I run a set of ported and polished early C9's (Basically), and they perform REALLY well.

Just bought another complete, running Hardin Marine 460 and am curious if I should even bother with changing out the heads.

Ray

I was gonna say, 40amps?, I have 2 breakers and they're both 30 amp.

Ray

Yeah huh, VERY pricey for that feature, although I can see the benefit of the "free wheeling" feature, still not convinced it's worth the $1300 though.

Ray

Also be forewarned the JE pump I beleive is epoxied to the hull, so might be a bit fun getting the housing out.  Can't really change it to another style pump easily either.

Good luck with it. (only stuff I have from a JE is the nozzle, with rudder, and a reverse bucket painted titty pink and says Moooo on it, if you need it).

Ray

I stuff one up the nozzle. Just be careful, not too far!

Ray

You're right, that IS totally unuseful, 

But neat.......

Ray

If you try to make automotive practices work in a boat, you will not be successful, period end of story.

MY-my what an intersting thread... Motors alone don't make speed in jets.

Very good info, Just in those quotes! I'm from a hot rodding background on this too and really just getting a grip on all this. Those 'charts" you refer too are really just guidelines based on generalities. I think the idea is to aim the peak HP rating and RPM it hits that number at the chart and select your impeller from there. I think this is a bad practice, myself. While maybe a good STARTING point, you'll still have to experiment going up and down impellers to best match your engine/pump combination IMHO. (The Moo I got pretty lucky, but still plan to test a B AND an AA over the winter in her).

And They're right, much more to it than just the engine/impeller. Cav plates, loaders, how tight or fresh the pump is, how it's mounted, even down to what paint is on the bottom of the hull and how it is applied and it's texture.

76MPH is easy for me to beleive as the Moo can do that at will. Blind squirrels find acorns once in a while! Just don't bank on the charts saying this isn't possible. The end goal is total efficency of the entire system, and in a Jet Boat, not an easy thing to tweak sometimes. (Ask Jeff, he has his hands full tweaking his former drag boat).

HP ratings and what we get from a dyno to real world applications is a different matter. And to my opinion, it doesn't really matter, as long as the engine is solid and can reliably drive the intended drivetrain and connected vehicle to the desired results consistently and not break, I'm down with it!

Just my .02

Ray

I say this as I'm building something totally INSANE that was supposed to be a cruiser, lol.

Umm Yeah, and check the siggy line, 

Ray