Thread: Counter Rotation Vortec cam question (boat)

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Any other good cam optioins for an HEI Carbed 97 Vortec in an older inboard ski boat. What would it take to run a early 80's flat tappet gen 1 style Counter Rotatio cam in the Vortec ? Are the Vortec Cam/crank different then the older gen-1 set up.


The Gen 1 flat tappet cam I am running in my 89 Suburban engine (converted to counter rotation) is Gear drive (Gear to gear).


The Mercruiser Cam Part # RA050022 Description: 5.7L RH Camshaft (1997 and Later) List Price: $577.50 This seems like an awful lot of $$$ for stock power.

Yep, Mercruiser, Volvo, and the others think their parts are made of gold, don't they? Funny part is, most of their parts have GM numbers stamped all over them that you can buy at a Chevy dealer for a fraction of the cost. But if you ask them they say their parts are special, heavy duty to withstand sustained high rpm usage..............yeah, right.

Wish I could answer your question, but I would call any of the reputable cam makers like Comp Cams, etc and ask their tech guy what they have to offer for your engine. Some years back I used an S10 V6 Vortec for a Chris Craft boat I had, and the truck grind worked out about right and wound out to about 4600, right where the more expensive Volvo Marine cam would have peaked. So I suspect some cam smart tech guy can get you one you want.

Don

Things that I do remember from my Vortec builds:

Cranks on ALL Vortec motors (96 and up) are 1 pc rear main seal
Front of crank has slip on reluctor wheel for CPK (crank position sensor)
Front of crank accepts standard type balancer

Cam has NO fuel pump lobe on Vortec
Vortecs are all roller lifters
Vortec heads do not guide the pushrods, the rocker arms are have the slot that rides on the valve tip
The distributor drive gear looks normal

mike in tucson

isky .erson. com cams .crower. all can grind you a cam for rev rotation if they have a core there is old flat lifters cam s in rev rotation ? but why would you go flat lifter cam? you would have to use a older timing set longer push rods then hyd roller

I don't think I'd use a flat tappet cam in a block that is roller-ready. CompCams will probably have the best price on a roller cam for your application. Call up one of the tech guys and talk with them....The first cam on the list is usually the one to use for a mild application and the first one in this case in the marine, roller cam, carbureted section is the 08-416-8. That is the number for standard rotation. Talk to the tech guy to order reverse rotation.
1-800-999-0853

nope i think comp is a player but not the best price . speed pro had some marine cams in flat lifter . can not forget Howards Cams . i been buying 3 cams roller cams a week my best deal is erson cams . comp is more and i a dealer for . all i listed but isky

Thanks guys,
I want to stay 5.7L Vortec roller but cam availability and cost are swaying me to look at other options. This boat engine will be used like a industrial hydraulic pump ~ needing good strong linear grunt.



Howards has nothing for 5.7L Vortec RR roller and recomended Erson

Called Erson 2x and left voice mail...

Comp has nothing for 5.7L Vortec RR roller and recomended Web.

Searchign for Web Cams suxxxxx ~ (Computer cameras) Webb Cams hit the mark...
Web opens at 8am Pacific but at 8:05am Pacific still get after hrs voice mail.
8:23 Web answers phone ~ Lady on the line doesn not know what a chevrolet 5.7L Vortec engine is, but she offers to sell me a 16v cam for a Chevrolet Colorado. Other girl in back ground talking LOUDLy about getting make up issues resolved. I feel sorry for the owner as I'm sure he was strong armed into supporting these less then knowledgable folks.

Speed Pro required me to fill out a laundry list of info for an on-line information request thru Federal-Mogul corperate computer system.

Isky still not answering the phone ...
8:30am Pacific Isky answers but their marine folks are not in until after 10:30...

Flordia Inboards has the PCM RA050022 RH marine vortec roller camshaft for $476 + shipping.




Any other suggestions???

At $500 for a cam the Vortec is $1k premium (with other necessary marine pieces) over a standard 350. I might have to look at building my 89 350 with Vortec heads / intake / and a flat tappet RR cam.

The big snag as I see it is this:
GM Performance Marine does not offer the Reverse rotation 5.7L. Along about 1995 the marine industry began building reverse transmissions that could handle = power forward or reverse. Thus the reverse rotation engine numbers were greatly reduced as the Vortec design began .

One thing I have to ask. Is this a single engine boat? Generally, they are not counter rotating, are you sure it is? Some boat manufacturers do put counter rotating engines in a single application, but not often. What is your drive system........sterndrive, straight drive, etc?

Don

Erson retuned my call and spoke at legnth about the issue of marine guys locking down the RR Vortec cores. If I can find a RR hydro vortec core he'd be glad to grind one. He also spoke of the options of going thru a company like LSM for custom work, but that would be around $600 +/- ... He also confirmed that if I find one, then low $400's is a good price on one of these vortec hydro RR cams.

Very nice to speak to ONE knowledgable and helpful cam guy after 2 hrs of leg work and dead ends.



Itoldyouso,
I did the prostate exam last year ~ It is RR (See my hot rod upper rt of my post) Dixie 299 Inboard Ski boat 350 cid / Velvet drive
I swapped the RR cam in to a $300 Suburban engine to prove the boat out. Now with 25+ hrs it runs ok but burns oil at 1 qt pr 4 hrs. I've got a 72K truck Vortec under the bench collecting dust (200psi on 6 cyls and 2 are low). Silly cooling quick connect leaked and it ran hot on previous owner.





I can flip my 71c trans and replace my prop to run standard rotation but that is blasphmy in the ski boat world.

Still a little confused. Are you saying you swapped a RR engine into the Suburban?

Don

Sorry for the confusion ~

Bought ski boat with frozen engine / busted block.

Bought $300 Suburban engine (got to test drive).

Swap cams to make suburban engine RR.

Install in ski boat and I have a cheap high miles RR 350.

Proved out boat / hull / trans / family likes boat and enjoys skiiing.

Now I'm ready to invest in a fresh R 5.7L mill for the long haul....

How does $ 295.63 sound for a cam? I called one of the distributors I used to deal with when I was in the marine business, and he will sell you that RR cam for that amount. If you want it, call Steve at Flagship Marine, 941-639-5345 and he will take care of you.

So you get the right one , you can ask him all the questions , I just wanted to hook you up with someone who can save you some money.

Good luck.

Don

B I G Thanks ~ Will call them now....

In stock and ready to ship for said price ~

THANK YOU DON !!!!

You're welcome. Flagship is very good to do business with, you will have no problems. When I was in the business we probably bought 40 engines from them, every deal was a good one. My own Son Don is running one of their crate motors in his boat.

Glad this worked out for you.

Don