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-   -   632 1000 hp crate! Ready or not? (https://www.offshoreonly.com/forums/general-boating-discussion/383962-632-1000-hp-crate-ready-not.html)

jeff32 10-15-2024 06:08 PM

632 1000 hp crate! Ready or not?
 
Just got 2 of those nice engines!
what are the marine engine builders comments on that engine in a boat?
https://cimg4.ibsrv.net/gimg/www.off...9180a7d65.jpeg
https://cimg5.ibsrv.net/gimg/www.off...b4c8ddd33.jpeg
https://cimg6.ibsrv.net/gimg/www.off...a08710bca.jpeg
https://cimg7.ibsrv.net/gimg/www.off...d26eb4886.jpeg
https://cimg8.ibsrv.net/gimg/www.off...8b0872a1e.jpeg
https://cimg9.ibsrv.net/gimg/www.off...fc8a70eee.jpeg
https://cimg0.ibsrv.net/gimg/www.off...a50d90ff8.jpeg

B38 10-15-2024 07:18 PM

If you run dry exhaust, yes

SB 10-15-2024 07:36 PM

Holy cow ! Congrats.
subscribing.

tommymonza 10-15-2024 07:38 PM

I thought there had to be some clearances opened up on them being they weren’t built for marine use.

There was a guy on here years ago that ran some GM 572 Crate motors but I can’t remember how he made out.

Here is one of the threads on the crate 572/ 620 hp.

https://www.offshoreonly.com/forums/general-boating-discussion/106336-so-we-went-boating-today-5.html

SB 10-15-2024 07:38 PM

Btw: the exhaust ports are not standard location, did you plan on bigger $$$ exhaust ?

B38 10-15-2024 07:45 PM


Originally Posted by SB (Post 4911617)
Btw: the exhaust ports are not standard location, did you plan on bigger $$$ exhaust ?

agreed, maybe 20k to build dry exhaust that's water cooled. Stainless Marine will love you.

tommymonza 10-15-2024 07:46 PM


Originally Posted by tommymonza (Post 4911616)
I thought there had to be some clearances opened up on them being they weren’t built for marine use.

There was a guy on here years ago that ran some GM 572 Crate motors but I can’t remember how he made out.

Here is one of the threads on the crate 572/ 620 hp.

https://www.offshoreonly.com/forums/...g-today-5.html

repost so link shows

F-2 Speedy 10-15-2024 07:50 PM

Put that ***** in a COPO Camaro and go spank some Mustang, Dodge A$$.........:lolhit:.not in a boat.......:angry-smiley-038:

tommymonza 10-15-2024 08:18 PM

From Raylar years back



#11

Raylar , 03-03-2012 12:51 PM
Registered
All good points and sugesstions.
As for clearances we like to use on stock GM shortblocks are slightly different than for aftermarket specialty products we can use in a block. For the stock GM type crankshafts and rods we use what we call the 2.5 sizing or .0025" on rods and .0025" on mains. The GM type crate engines can be anywhere between .001" and .003" Piston clearances and ring gaps will vary based on forged (4032 alloy) and hypereutectic cast pistons. Ring gaps can vary all over the board depending on who assembled them. We like to see .024" or so on top ring and .022" - .028" on second ring depending on piston type and induction system. On long blocks valve guide clearances should be checked and brought to normal .001"-.0015" intakes and .0015" -.00175" for exhausts. Also should check installed spring heights and verify good valve seat face to valve seat patterns and seal. There are obviously a lot of clearances that can be checked and set properly and it will depend on the original builders base part qualities, specifications, machining processes, measurements and attention to detail during block prep and assembly.

Would I take most of the better crate bbc engines I have seen properly fitted and cammed and put them in a mild 300- 420HP replacement use in more pleasure/performance hulls and run them at 4000-5000rpms in lake and river enviroments with most usage at idle and cruise rpms- YOU BET!.

Would I take some of these same crate bbc's and put them in higher speed performance boats in bigger water and ocean wave enviroments and run them with 450-550HP levels at 5000-5800 rpms for moderate sustained near WOT runs, poker runs or long up the lake blasts - HELL NO!

Best Regards,
Ray @

BBYSTWY 10-16-2024 02:47 AM

Did you get build sheets with them regarding bearing clearances? In theory...these are hand built engines so kinda depends on how it was built really. I'm no builder like some on this board but to totally throw out the idea without having that info seems kinda silly to me....Congrats btw! Bada$$ hardware sitting there! :riding:


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