How much more fuel do u burn?

Yes on the o2 set up for tuning the carbs.

I wouldnt bother with webers as any thing ur bldg for a boat is probably gonna want a dominator

Bring outthe four valve dohc bbc some titanium rods and its a perfect world foe 1000hp na hi rpm durable engines

I don't see that marine NA engines have hit a power plateau. The NA stuff is just getting better...

I can get 1000HP from a 2 valve 800CI engine with kitten like manners. Why bother with the complexity?

My "relatively" cheap new 588 makes 800Ft LB,

BUPS new 665 will make 900/900...


UD

To get longer life out of em need to lighten up the rotating assm. 4 valve dohc and you could fev em higher not have to run a bunch of spring pressure or lift... would be a much lower maint package with a lot more longevity

For sure you can potentially lighten the valve train with a DOHC 4V setup and turn more RPM, but you still pay the complexity cost at build and rebuild time with much more machine work and parts overall.

Pretty sure the high RPM DOHC designs are solid shim under bucket vs hydraulic- thats a hell of a lot of stuff to pull apart and adjust manually at regular intervals.
One could make it a forked tappet like my old GS1100's were.

With bigger cubes you can turn the RPM down keep your spring pressure in check and bring back your longevity without the complexity cost and maintenance.
Alexis 800 cube deal turns 8K, if you turn that down to 6 you get lots of life and still tons of power.

The concept of a giant motorcycle engine is appealing for certain!
Maybe Merc will make an NA version of their DOHC deal some day.


UD

Z1s had shim over bucket a gazillion of em were soldd. Easy as hell to maint.
the valve train never needs much maint cuz the bucket doesnt side load the valve and wear out the guides.

If merc built em theyd still cost huge coin. The tuff part is how to retro fit and drive the cams i think. If it was a bolt on head to old school block they would sell like crazy

I may be wrong, usually am,but I thought Merc said that they now offer the motor without Turbo's...Something like 800HP or something like that. Not like anyone has bought it...but...thought I'd bring it up in case my memory for some reason is correct.

Heard about these things in the wild at shows never seen one in a boat. Sounds *****in.

UD

I guess if you have the room you could make it easy- I always think of working on bikes and shim under is basically searing in hell the duration of the job .

The bolt on 4V heads always seemed like a good idea, and several guys have tried the "bolt on 4V head" thing like ARAO and and one or 2 others I don't think Ive ever actually seen the heads outside of the interwebs.
Arao basically seems to be a con artist.

UD

They do offer an 850 "race" version but it still has turbos http://www.mercuryracing.com/sterndr...gines/class-1/

Lets hear more about this 588! Do you have another thread about it?

It doesnt really fit in this thread so I didnt volunteer it as anything other than an example of an alternative to tunnel rams and or highly complex engines.

Here is the mill.

Its in a couple threads - The under 25 thread

http://www.offshoreonly.com/forums/g...hem-up-64.html

and this thread.

http://www.offshoreonly.com/forums/l...upgrade-2.html

Ought to be a riot- have to button up the interior a bit and do a bit more work- I'm "jonesing" to go stand on it.

Boat went 90 with a 500HP small block and was grandma level easy to drive- this should wake it up it a bit.

UD
http://i.imgur.com/FCKcy0d.jpg
http://i.imgur.com/KQ51SHx.jpg

ud,that is a good looking boat!

Thanks Mike! Its a fun little machine.

Next time you make it to Cali look me up and Ill make an excuse to take an afternoon off and well go for a spin.

Toward the end of the clip you can hear how quick it revs - https://www.youtube.com/watch?v=rRPJkpmB7ns



UD

The 4v heads breathe way better at partial lift than two valve. The valves weigh about half as much on a 4v due to the head of the valve being smaller and the shaft is just a short nub to hold the retainers. Prob about 40% of the spring pressure id bet you get three times and as many hours or more before you have to check on em. Easy to do a valve adjustment on a shim over bucket 4v.

My shaffiroff racing 540 makes 804 ponies @ 6500.

Making a 1000 na hp single dom shouldnt be hard if you go big cubes.
i am talking 4v to be able to make that big hp and have half the maint and twice or three times the engine lifespan. If you bult that u would sell thousands to the perf crowd. Cast a hardin log style ex manifold and intake and sold the package deal. A cnc machine running 24/7 and cohld sell as quick as you mAde em if it was a bolt on package deal.

Run a tunnel ram on it. If your going on the dyno i wouldnt think setting up a tunnel ram would not be to difficult

Agree on partial lift flow superiority and lightness. There is a valid reason why clean sheet engine designs almost always dohc 4 V. Agreed on shim over being a breeze - until/unless an over rev spits it out.

I think for it to work like the brochure the scheme needs a true DOHC vs a cam in block retrofit which is loaded with compromise. Agree if you could get it to work and make an affordable package you could keep a CNC machine running 24/7.

Love shaffiroffs car stuff, never seen his boat mills, but heard he's done them. Do you have a thread elsewhere on your mill. Dont want to side track this one any more than I have, but would love to see the mill.

Tunnel rams, never seen one that didnt give up low end.
All the Tunnel ram dyno runs I have seen all start out at like 3500 RPM or more usually 4K.
(thats usually code for someone to pull one out at 2800)


UD

Well, it became true overnight. LOL.

Here you go:
http://www.offshoreonly.com/forums/g...te-engine.html

Drag race guys on yellowbullet are swearing by have their particular valvetrain setups run on a spintron. They are sending them to 3v for testing and end up running much lighter spring pressures. For multiple seasons some are claiming. Worth looking into for $1500.

But if it was a retro fit for old school bbc you could keep the cost way down.
what if u pulled your cam installed another with just drive gear for the oil pump and a drive gear up front to drive a vertical shaft to turn the cams that you made a support cor that anchored in the lifter bores.
Hemi head x flow for flame propigation a double 4 bbl moderate height manifold crank trigger ign to keep the hheads as clean a possible? The manifold could have equal spacing and be straight ports due to not having pushrods.

My shaffiroff 540 was an unclaimed eng. Guy paid 50% deposit and vanished. I paid 13k dragon slayer crabk manly rods full cnc pro 1 heads msd dist. Top of the line everything incl 1050 dominator

That solves the pushrod problem. If you build it Ill come! I'd drop coin on a config like that to try it if it came from a reputable shop.

Sounds a bit like what Mercs doing. Interesting to me they claim an LS base.
Ilmor claims (to their surprise) they had to completely redo the oiling system for sustained RPM running.
I wonder what tricks Merc plays.

Great deal on a zero hour killer BBC.
Whats it in ?


UD

Love this stuff. I had a friend of friend years ago with a 34 sutphen with tunnel ram engines in it. What a beast. One of you Jersey guys probably remember the boat. Someone down there was Dave's "guy".

Badazz rides just never see many around

The dude that ordered it checked damn near every box for upgrades.
dart block callies dragon slayer crank manley rods je slugs pro1 heads full cnc porting was worth a hundred ponies msd trick everything its living in a 67 pro touring camaro with a full dse chassis setup. Mark stielow desidned all the chassis stuff baer brakes fully adj suspension. 714tq 804hp @ 6500 hyd roller valve train. Im gonna going to swap in a solid roller and spin it 8k... rm

Sounds like an absolute riot to drive.
Lucky move picking up someones high quality abandoned project for pennies on the dollar.

UD

Racinfever Are you still in the boat game ??