camshafts

Is there a difference in cams from a 1995 260 mercruiser and a 280 magnum? does anyone know? I'm gonna be going thru another rebuild due to an overheat issue. I see that I got on my engine now the 300hp crate engine heads that came with the 260 merc so I see that there is a plus allready. I would like to buy the magnum cam if it is different for a better gain in power. The rest of the motor is two bolt cast. It is a flat tappet too.

Re: camshafts

Mercruiser really only has two different cams in their 350 SBs. A flat based hyd cam and a roller hyd cam. In the early 90's either cam could have come in your engine. Both produced the same hp in the same respective engines. You can check this by going to any of the Mercruiser Parts Look-up sites.

The main difference between a '95 carbed 350 Mag and a 5.7LX, is the high-rise dual plane intake on the Mag. Even though marketing literature would make you believe the mag has more hp, when you look it their service manual, they are rated the same.

PS: Those are the same heads I had on my '97 5.7L. I imagine you have the dished pistons, as well. I put on vortec heads this spring.

Re: camshafts

My pistons are flat with valve reliefs. If I can remember correctly I think there is a 217 in the last few digits of the heads. I went to a site to identify them and they were crate 300 hp heads. I have yet to figure out what vehicle the block is in just in case I need one. It is a roller acceptable block, 1 piece rear main with a mechanical pump.

I would like to use Vortec heads, I been on this all day today actually. I read on here that this is the extra power ticket. What ones am I looking for and do they need to be anything special for marine use? What car or truck are they in?

Is there anything else I have to do to use them for Marine use? like pushrod change, seats, springs etc...?

Will my stock rockers work?

What intake will I need for salt water?

I just bought a new Edelbrock 600 marine carb too, will this work on the newer manifold?

Thanks a ton guys!

Re: camshafts

My pistons are flat with valve reliefs.

They should have valve reliefs, but you should see about 1/2" in from the outside diameter, and 2mm depression through the rest of the pistons.





If I can remember correctly I think there is a 217 in the last few digits of the heads. I went to a site to identify them and they were crate 300 hp heads. I have yet to figure out what vehicle the block is in just in case I need one. It is a roller acceptable block, 1 piece rear main with a mechanical pump.

My heads had a casting number of 14096217. The heads are 64cc, to match the low-compression pistons. Even though most head id sites only say crate, if you search long enough, you will find referances to marine heads.



I would like to use Vortec heads, I been on this all day today actually. I read on here that this is the extra power ticket. What ones am I looking for and do they need to be anything special for marine use? What car or truck are they in?

The stock GM assembled heads are fine. That is what is in new 5.7 mercs.


Is there anything else I have to do to use them for Marine use? like pushrod change, seats, springs etc...?

No, as long as you are staying with the stock cam profile. Stock vortec will not take allot of lift, and will need rework if going with much lift beyond what the stock roller cam has.


Will my stock rockers work?

Your stock rockers should be self-aligners, which are required on vortec heads.


What intake will I need for salt water?

If raw water cooled, you will need a marine specific alum intake that has bronze linings in the water passages. I am not aware of any cast-iron vortec intake manifolds.



I just bought a new Edelbrock 600 marine carb too, will this work on the newer manifold?

Yes, if you get a square bore intake. Some minor tuning may be required.

Re: camshafts

Your quote is...."No, as long as you are staying with the stock cam profile. Stock vortec will not take allot of lift, and will need rework if going with much lift beyond what the stock roller cam has."


I have the Mercruiser flat style tappet cam, will this work with Vortec?

What year head am I looking for or numbers?

Are all Vortec heads the same?

Re: camshafts

Yes, the flat lifter cam is fine. It has lower lift than the roller cam.

Just get new vortec heads. Once you figure shipping in, its hard to beat Jegs or Summit Racing.