Help with Engine and Cam ID

[bocco]

Hi All
I'm looking for some help figuring out what I've got in an Eliminator V-drive that I purchased recently. It's a 454 and the casting number on the heads (6272990) say that it's a 425HP crate motor with open chamber rectangle port heads. Tag on the block says Harman marine. Now if I assume that the motor is original. Does anybody know what that motor should have in it as far as cam, crank, rods, etc?
It sounds like a solid cam and it sounds like the valves need adjusting. Can I tell if it's hydraulic or solid without taking of the timing cover to find a number on the cam?
It's been 25 years since I did any fun wrenching so I'll take any help I can get.
Thanks
Gary

[GofastRacer]

Sounds like an LS6 to me!.:rolleyes: It should have a steel crank, 7/16 bolt rods, solid lifter cam!. You won't find anything on the front of the cam, it's on the back end. Just pop a valve cover and try and push down on a rocker arm, if it moves down you have a hydraulic cam, I bet it's a soilid though!..:)

[MikeF]

We'd like to see some pics of the boat! What year is it?
If it has not been run in awhile, that cam will have nearly no oil on it. Probably want to start and run it around 2k rpm to get the cam good and wet from the slinging oil off of the crank.

[bocco]

I was guessing LS6 but the casting number is different on LS6 heads. I've been checking some of the web pages that show Chevy casting numbers and the LS6 has a different number on the heads but the same description and horsepower. I'll try pushing on a rocker to verify if it's solid. I'm hoping that I can use the specs for an LS6 cam to adjust the valves.
I havn't taken any pictures of the boat since I bought it but it's still in the HB classifieds about the middle of page 3. It's the 81 Eliminator mini daycruiser.
While I'm typing.....the boat has a dual quad tunnel ram setup on it and I'm thinking it would just as well if not better with a single 750 or 850. Don't tunnel rams run best at 6000 RPM or so? That's got to be a bit much for a 20 year old stock motor.
Thanks for the help
Gary

[Foggerjet]

I'm guessing you checked Mor-Tec,but here it is anyway. 6272990....70-up...rect...OPEN...454 service replacement, used on some MKIV crate engines, 118cc chamber

[Mohavekid]

Nice looking boat.:D
Per my Harman Marine catalog, their 405 HP Chevy had the following parts:
7/16 High-Performance push rods
Forged TRW pistons
LS-6 Rods with 7/16 bolts
Forged crank
Four-Bolt High Performance Block
Compression Ratio 8.75:1
The rest of the stuff listed seems to have been changed on your motor.
I have the same motor in my boat and I believe the cam is hydraulic. Your cam may have been changed out when the intake and nitrous was added.
Here are your pics.
http://www.***boat.com/classifieds/ads/images/588_1.jpg
http://www.***boat.com/classifieds/ads/images/588_2.jpg
http://www.***boat.com/classifieds/ads/images/588_3.jpg

[bocco]

[QUOTE]Originally posted by Mohavekid
[B]Nice looking boat.:D
Per my Harman Marine catalog, their 405 HP Chevy had the following parts:
7/16 High-Performance push rods
Forged TRW pistons
LS-6 Rods with 7/16 bolts
Forged crank
Four-Bolt High Performance Block
Compression Ratio 8.75:1
The rest of the stuff listed seems to have been changed on your motor.
I have the same motor in my boat and I believe the cam is hydraulic. Your cam may have been changed out when the intake and nitrous was added.
Mohavekid,
Thanks for looking that up. I'm wondering about the compression though cuz the tag says to run 94 research octain gas. I know it's not the same as R+M/2 but with 8.75 you could run just about anything. The tag also has a model number HM9-C-6370. Is that in your catalog? Do you know if Harman Marine actually built these engines or just bolted on the Marine stuff.
Thanks for the help.
Gary

[Mohavekid]

Bocco,
The it looks like the tag you're reading is the serial #. According to my catalog, the Harman part # should be MEN21-03104S.
The catalog lists fuel required as premium via the research method. The tag on my motor indicates 88 octane via the research method. There seems to be a descrepancy between the catalog and the motor.
I don't know if Harman actually built the motors, I suspect not. I suspect they just marinized them after purchasing them from GM. There were some "custom" options listed, including a cam package, extra capacity oil pans and special intake manifolds and carburation.
I see you're in Livermore. Where do you do most of your boating?

[bocco]

Mohavekid,
The number HM9-C-6370 is the only number on the tag besides 454CID, 94 octane and 32 degrees advance. I'm guessing it's about what you described but with slightly higher compression. If pushing on the rockers indicates solid lifters I'm gonna try to adjust the valves to stock LS6 specs.
I do most of my boating on Lake Don Pedro as we have a houseboat there. Occasionally hit the Delta.
Is that your Sanger in your avatar. My cousin has one in the same colors with a V-drive that he runs on Clear Lake mostly.
There was a sweet one on display at the boat show in Pleasanton this year. The only real V-drive in the show.
Take care
Gary

[ssmike]

That looks like a nice clean daycruiser.

[superV]

Bocco this is my old boat I can help you out a bunch! Its a 405hp LS6 from hardin stock as a rock. Bob added the ram and nos after he got it from me but never really ran it give me a call. I sent you a PM.