Formula F-206 1987 engine rebuld
 

I'm rebuilding a 1987 260hp merc mag. anybody have any suggestions for mods cam? intake?carb?ignition? any help woud be greatly appriciated.

Re: Formula F-206 1987 engine rebuld
 

Im running late for work or I would post more....BY FAR the best thing you can do is get a copy of Dennis Moore's book "Small block Chevy Marine Performance
http://www.allbookstores.com/book/1557883173
Small-Block Chevy Marine Performance : Engine Modifications for Maximum Boating Performance

This is the BIBLE for small block marine engines....Every detail is discussed and will save you TONS of money in the process....

Bh

Re: Formula F-206 1987 engine rebuld
 

Yeah, what he said.
That book is thee place to start. You'll find tons of info and recomendations on cam selection, intake, heads, etc.

Re: Formula F-206 1987 engine rebuld
 

A couple of years ago, I was involved in a project for Family & Performance Boating magazine. We had a 22 Scarab with a stock 350 Magnum. We removed the motor pulled the heads, had a valve job done, swapped out the cam with a complete Comp Cams kit (hyd rollers,rockers, springs) and an Edelbrock intake & carb. Exhaust was swapped with a pair of Stainless Marine units. Short block remained stock.

The results were pretty dissapointing. We gained nothing. Zero...

The bottleneck was the stock heads. They just don't flow very well.

I'd suggest saving your money and dropping in a crate ZZ383 from the Chevy Performance catalog. They work incredibly well in a boat application, just drop it in with a good exhaust system, 750 Holley and a decent intake. Pace Chevrolet has them for $4850. Last summer I helped a buddy of mine drop a pair in a 26' Sutphen and he instantly picked up 10 mph! They run strong.

Good luck,

Kurt

Re: Formula F-206 1987 engine rebuld
 

well buying a 383 crate engine does sound nice but I'm on a tighter budget than that due to a lot of other repairs that are being done right now as well. it sounds like a set of heads is the best thing to do I've heard of people using VORTEC chevy heads and having big gains not sure if it's true. I'm for sure going to use the comp cams performance marine grind cam with a performer intake and edelbrock carb. now I'm thinking about the heads..

Re: Formula F-206 1987 engine rebuld
 

switching to the Vortec Heads will net you an EASY 40Hp..... I used Dennis's Book and have a 358 SBC Pushing 380hp@5200Rpm's......

Re: Formula F-206 1987 engine rebuld
 

I gained almost 2 (GPS)mph switching to thruhull Stainless Marine Exhaust on my 86F3LS with the 5.7....This was with the original motor with about 700 hours on it...All in all I have gained 9mph going from the stock 350 to my new 358 Roller

Re: Formula F-206 1987 engine rebuld
 

what kind of boat are you using for the 358 roller motor?

Re: Formula F-206 1987 engine rebuld
 

well it looks like I'm going to have a pretty stand rebuild nothing to fancy this time.
1. bore .30 over
2. edelbrock intake
3. edelbrock marine carb
4. compcams performance marine grind cam

hopefully it will produce a little more than 260hp but I'm not sure it will gain to much.

Re: Formula F-206 1987 engine rebuld
 

1986 F3LS