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Old 10-31-2016 | 05:03 PM
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Originally Posted by SB
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.
They do offer an 850 "race" version but it still has turbos http://www.mercuryracing.com/sterndr...gines/class-1/
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Old 10-31-2016 | 05:05 PM
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Originally Posted by Uncle Dave
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
Lets hear more about this 588! Do you have another thread about it?
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Old 10-31-2016 | 05:23 PM
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Originally Posted by offshorexcursion
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


Last edited by Uncle Dave; 10-31-2016 at 06:20 PM.
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Old 10-31-2016 | 06:56 PM
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ud,that is a good looking boat!
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Old 10-31-2016 | 07:29 PM
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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

Last edited by Uncle Dave; 10-31-2016 at 07:34 PM.
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Old 11-01-2016 | 12:09 AM
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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

Last edited by iliveonanisland; 11-01-2016 at 12:16 AM.
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Old 11-01-2016 | 10:17 AM
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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

Last edited by Uncle Dave; 11-01-2016 at 10:39 AM.
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Old 11-01-2016 | 12:40 PM
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Well, it became true overnight. LOL.

Here you go:
http://www.offshoreonly.com/forums/g...te-engine.html
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Old 11-01-2016 | 01:29 PM
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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.
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Old 11-02-2016 | 09:51 AM
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Originally Posted by Uncle Dave
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
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
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