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454/365 question

Do the 365hp 454s have forged pistons? Roller cam?

Thanks,

Clayton

Re: 454/365 question

Forged pistons yes.
Roller cam in Gen VI engines, 1996 and newer.

Re: 454/365 question

The Merc 454cid/365hp engine came with the very crude stamped steel rocker arms, but it does have all forged parts---crank, 7/16" rods, and pistons including a 4-bolt main block, and rectangle port heads. I don't know up to what year that Merc produced the 454cid/365hp engine, but when it first came out in the mid to late 80's it came with a flat tappet hydraulic camshaft.

Re: 454/365 question

Thanks guys. Just wondering if these engines were a good candidate for 525sc conversion. Sounds like they would be o.k. with a cam change and maybe some roller rocker arms, and the blowers of course.

Later,

Clayton

Re: 454/365 question

A Merc 525SC is/was basically the 454Mag with a supercharger.
Dished pistons, Crane cam, and roller rockers are among the differences.

Re: 454/365 question

Might be worth a set of low compression pistons if you're doing a rebuild.
The 525SC CR is only 7.5:1.

Re: 454/365 question

had a set in old boat, good motors

Re: 454/365 question

Quote:

Originally Posted by ctadams21

Clay, I would say "yes" to your question. On the reliability side, I would at least add some roller rocker arms, ARP rod bolts, hydraulic roller cam/morel lifters, and a good set of pistons designed for supercharging---heck, the pistons you have may even be okay to use for supercharging, but if you want to be top notch I would consider new pistons. I would also and have the engine(s) balanced.

Just make sure you have a precision machine shop who is known well for their machine work and good reputation----a shop that is very familiar with clearances needed to make an engine survive in the marine performance world.

"rmbuilder" (Bob Madara)is a good man to contact for valve train components, and very helpful when it comes to cam selection. Have fun with your project.

Re: 454/365 question

365 motor has Trw L2399 forged pistons. I believe .095 dome. BBB