TOPIC: water manifolds?

Hi everyone. Trying to find out if they make water exhaust manifolds for a buick 350. No luck so far. Any info would be great thank you.

Hi,
I read your other post too. OMC used the 300 V-8 and the 225 V-6 Buick. These are the same blocks except the V-6 is 1 cyl short on each bank. You are not going to parts exchange much between the 350 and the 300. The cam in the 350 is probably going to be OK, but not optimized for marine. Pedestrian auto 350's have pretty torqey conservative cams which is basicly what a marine cam is.
Regarding all the comments on valve seats, 73 and later will have the hardened seats in the auto 350. 71 and newer have lower compression which would be what you want for the boat. 70 and older have higher comp ratios. Carb from the 300 will be jettted wrong for the 350 and if a 4BBL will be the older Rochester swuare bore rather than a Quadrajet style that would be the 4 BBL on the 350. If they have 2 BBL these have similar styles at least, swap out the jets and the richening spring. USe the 300 carb (marine) on the 350 i you can swap the jets.
It's important to have a marine fuel pump and flame arrestor installed. The 300 pump will not like metahnol in the fuel so get a new pump. The 350 is aoutomotive and should not be used. Mallory or Holley MAY make a marine pump still, if not go electric marine. The pump has to be compatible with alcohol use make sure that it is.
The timing chain cover on the marine motor is CAST IRON on the car it is aluminum. I think the covers are all the same so swap it out use all cast iron on the marine. The oil pumps are in the timing cover and there are kits to boost pump performance, get one, it is a Buick weakness.
Look at a Buick performance supplier, there are still a few specializing in Buicks. Rotation will be the same.
You can find aluminum water cooled manifolds from Glenwood Marine
That's the best you are gonna do. Here aluminum is OK as water is not contacting both metals at once like in the timing chain cover.
You may find the the exit position of the manifold is not correct to fit to the out drive but you probably can adapt something.
Personally I'd rebuild or repair the 300 rather than swap in the 350 but that is me. You may find the motor mounts do not line up as the blocks are different widths. Also, the outdrives have torque and HP limitations I believe OMC stepped up the outdrive for larger V-8's.
Good luck!
Randy

either way V-6 or V-8 which ever you have GLM or Osco will have what you need. There are plenty of after market marine manifolds out there.
My engines were 1959 293's Randy that is why I did the hardened valve guides.

Like said in the other post..need manifolds, Fred Warner..link

shop.ebay.com/fredwarner1/m.html?_nkw=&_armrs=1&_from=&_ipg=25