Where is the weak link ?

[84EdH]

I have a 1979 century that I repowered with a 5.7 vortec engine. it has a 1409 Edelbrock carb, mechanical fuel pump, and cast iron high rise intake manifold and the newer style high rise exhaust manifold. The outdrive I am using is a MR drive. I don't know the hp output of this engine set up, but I have read the pre-bravo drives were designed for 300hp or less.

What type of power usage should be avoided to not tear up my drive? I figure hole shot full throttle is bad, but what about wot with 4 barrels kicked in? Is this really an issue at all ?

help appreciated!

 

[achris]

Re: Where is the weak link ?

As long as the cam is a marine cam, that engine shouldn't make enough power to damage an MR in reasonable condition. Nice clean good quality gear lube, at the right level. (Best oil I've found for the drives is Mercury/Quicksilver High Performance Gear Lube)

Yep, full throttle starts are about as bad as it gets. Once the boats up and running, laying on WOT is ok. It's the sudden torque that does them in.

Chris....

 

[84EdH]

Re: Where is the weak link ?

I got this long block from a former omc dealer as a new engine, old stock. all marine components. marine cam. thunderbolt IV. any estimate on hp for this setup?

thanks Chris, for your expertise and willingness to share it!

 

[achris]

Re: Where is the weak link ?

I got this long block from a former omc dealer as a new engine, old stock. all marine components. marine cam. thunderbolt IV. any estimate on hp for this setup?

Probably around 260-280 hp...

thanks Chris, for your expertise and willingness to share it!

My pleasure...