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View Full Version : Is a roller cam worth the money??



flying tomato
10-10-2010, 04:43 PM
Here is what I have:
540 cid chevy, 10-1 compression, Patriot aluminum rect port heads, 850 demon carb.
Comp cams extreme marine 278h camshaft. (226/236, .560/.570)hydraulic

Have not put the motor back together yet and am considering going to a hyd roller cam. I want the motor to stay under 5500 rpms and want to make the most power. Also need recommendation on an intake manifold as that will be changed as well.

How much hp can I gain with a roller set up??????

Thanks again in advance,
Non Flying Tomato

Donziweasel
10-10-2010, 05:00 PM
I am running this intake on my 540, although it is a tall deck...... It is a prety nice intake.


http://www.dartheads.com/products/intake-manifolds/big-block-chevy-intake-manifolds/single-plane-big-block-chevy-intake-manifolds.html

gcarter
10-10-2010, 07:27 PM
Just curious.....
If you're re-using the same aluminum heads, are you planning on adding closed cooling?

mrfixxall
10-10-2010, 07:50 PM
just a heads up! patriot and procomp are casted from the same mfr.. make sure you at leaste invest in some manley inconel extreme duty exhaust valves http://www.competitionproducts.com/Chev-BB/products/401/

as for a roller cam yes it will give you 40-50 more hp..you will need to use rollr rockers also.

call bob mandara @ marine kinetics 585-654-8583, he will hook you up with the proper cam and lifters( he is the best cam desigher),,be prepared to spend $1200.00 on the rite roller set up tho..

flying tomato
10-10-2010, 07:59 PM
Please tell me that I did not just buy another set of junk heads. Are you serious? I called Patriot perf and spoke with one of their salesmen and specifically asked him about quality of his product vs. Pro comp. He totally sold me!!

I did buy Inconel exh valves.

Not feeling so good right now.
Non-flying tomato

mrfixxall
10-10-2010, 08:06 PM
Please tell me that I did not just buy another set of junk heads. Are you serious? I called Patriot perf and spoke with one of their salesmen and specifically asked him about quality of his product vs. Pro comp. He totally sold me!!

I did buy Inconel exh valves.

Not feeling so good right now.
Non-flying tomato


did you get them from Alabama cylinder head? im just going by what i have been told,, all the cheaper cylinder head castings come from the same mfr,procomp,patriot,canfield,,they just do the finishing touch to them..they are a little better but will not compete with dart,rhs or brode's life spand..

as the saying goes the nicer the nice the higher the price..theirs a reason their stuff is more expensive because of the type of aluminum they all use and the type of casting methods..:0

Dr. David Fleming
10-10-2010, 08:43 PM
Big block Chevy was originally designed for flat tappet cam either solid or hydraulic lifters. Roller cams were provided by Crane, Isky and others as a racing - hot rod conversion. Roller lifters were designed to be linked in pairs to keep them from rotating as flat tappet lifters do. The whole system was pretty aftermarket.

In the midst of the smog polution era with EPA demanding low compression ratios the big three auto makers were searching for ways to get back the 50 to 100 horsepower lost to Federal regulated engine designs. One cheap and easy modification was the 40-50 horsepower lost in camshaft friction and the roller cam design was addopted for mom and pop and their every day driver mobile. I don't think anyone makes flat tappet cams for production vehicles anymore.

Mercruiser went with roller cam in the Gen VI engines when they went to the one piece rear main seal - they changed the valley area of the block for roller lifter retainer plate and other modifications. Cam wear for flat tappet cams was high and at engines running near full throttle with high spring pressure the wear was extremely high.

I think you are trying to convert the older design to roller and is probably the way to go for a long living boat engine. Just be sure you get the engineering right.

poorboy
10-10-2010, 09:04 PM
I agree with Mr. Fixxall, give Bob a call. He can set you up with the correct roller cam and lifters or also the right flat tappet cam. If you use the flat tappet cam you will need to add an additive to your engine oil. It is called EOS and sold by GM at most dealerships or you can use JOE GIBBS oil which has an additive in it. I've delt with Bob numerous times and he is an ace to deal with and he is extremely knowledgable when it comes to marine high performance. Ask him about an intake also. It would not surprise me if he recommends an "air gap intake" and a larger carb for your 540 BB. :wink:

Conquistador_del_mar
10-10-2010, 10:35 PM
Here is what I have:
540 cid chevy, 10-1 compression, Patriot aluminum rect port heads, 850 demon carb.
Comp cams extreme marine 278h camshaft. (226/236, .560/.570)hydraulic

Have not put the motor back together yet and am considering going to a hyd roller cam. I want the motor to stay under 5500 rpms and want to make the most power. Also need recommendation on an intake manifold as that will be changed as well.

How much hp can I gain with a roller set up??????

Thanks again in advance,
Non Flying Tomato

Derebery Performance Marine told me they will not build any more marine engines without roller cams - they work so much better with the high performance, high RPM marine motors. They have done extensive testing on cams and valve trains, so I believe what they told me. Bill

LKSD
10-11-2010, 08:01 AM
Yep, roller cam is the way to go if you are in there & going to be replacing it.. ;) J