350 CID Carburetor

[2wheeldeal]

I have a 1976 24ft cabin cruiser Reinell with a Volvo Penta 350 CID 5.0L
My Carburetor needs work or I'm willing to replace it if that's the recomended path. Currently it has a 2 barrel Carter and I'm wondering if anyone knows what CFM I'll need to look for if I replace it. Should I go to a 4 barrel? WOT is 4200. Should I stick with a 2 barrel? The boat is used for both cruising and water skiing but I'd rather it ran well for the skiiing because I'm sure it would then run just fine for cruising.

So CFM?
2 or 4 Barrel?

Thanks

 

[xtraham]

Re: 350 CID Carburetor

stick with the 2 bbl, get the # from the carb pickup a kit a float, and a gallon can of carb cleaner from a local parts store, completely disassemble the carb soak it over night, wash it off with water, blow it out with compressed air install the new kit, they are very simple to rebuild,

 

[FreeBeeTony]

Re: 350 CID Carburetor

FYI.........a 350 is a 5.7L....................

 

[Scaaty]

Re: 350 CID Carburetor

Most 350's I see have 4 barrel's, and I tossed my Quadrajet in the trash, put on a 600cfm Edelbrock Marine carb, and have not looked back in remorse since

 

[2wheeldeal]

Re: 350 CID Carburetor

OK so we have one vote for the 2 bbl, one for the 4 bbl. Anybody else have the tie breaker answer?

Thanks all for the help thus far BTW.

 

[Boomyal]

Re: 350 CID Carburetor

If you go with a 4bbl, ya better learn some severe throttle restraint. When you get into the secondaries, you can watch your gas guage needle head south quick. You will undoubtedly notice the power difference when you want it, however.

I went from a 2bbl on my 5.0 ltr/302 and it made a signifigant difference. However, when I took it down to Shasta this summer, at $6 a gallon of gas, I learned some restraint in a hurry. You could still go fast but you better not do it in a hurry.

Also it is widely accepted that boats benefit most from vacuum secondaries as opposed to mechanical ones. Others might have a different opinion but the Edelbrock only has mechanicals

 

[Reel Poor]

Re: 350 CID Carburetor

It's just to easy to replace or rebuild the 2 barrel you have now.

Going to a four barrel will be a lot more costly and labor intensified for the small gain, although noticeable. Intake, gaskets set, throttle bracket, 4 barrel carb, fuel line, oil change, valve cover gaskets, exhaust manifold gaskets, setting timming, adjusting throttle cable, and who knows what else you may actually run up against when you open up a can of worms. If you were replacing or rebuilding the engine I would be the first to say, go for it. But this is not the case. Run what ya brung.

 

[John_S]

Re: 350 CID Carburetor

I've heard that some volvos with 2brl carbs, already have a 4brl manifold. Some sort of adapter plate is used. With only the cost of carb, gasket, flame arrestor, fuel line, and possibly throttle bracket, it might lean you to the 4 brl.

FWIW, the edelbrock 1409 and Rochester Q-jet have mechanical butterflies, but have vacuum controlled air flow. On both these carbs, there has to be enough airflow/vacuum to open the air door, when the secodary butterfly are open.

 

[xtraham]

Re: 350 CID Carburetor

my point with sticking with the 2bbl is like Boom and Rp

1- everything is already there= cheap

2- my experance with a vessel of that size, the secondarys will have to be open to plane the boat and

3- with the cost of fuel today it's not worth the small gain in top end

4- if you can afford the extra 3 to 4 gph go for it

 

[wvit1001]

Re: 350 CID Carburetor

Unless you know what your doing or are willing to pay someone else to do the work I would stick with what you've got.

And with a 24' cabin cruiser it's not like you have a speed boat anyway.

 

[2wheeldeal]

Re: 350 CID Carburetor

Haa ha, wvit you sound just like all my friends, it ain't like I got a pot of gold on the water here. It's just a sturdy old Piece of Ship, which I happen to like a lot. However you're all correct when it comes to gph so I think the 2bbl posse wins it. Thank you all for all the help, I'll go with the rebuild.

 

[imported_rosco]

Re: 350 CID Carburetor

first, a 5.0L is not 350cid, it is 305cid. a 350cid is 5.7L

second, you need to figure out the maximun CFM,s your engine will handle, that will determine what carburator you need. sticking a 700cfm 4 barrel on a engine that can only flow 500 cfm will do one of two things, 1. if it is mechanical secondaries, flood your engine out every time you floor it, 2. if it is vacume secondaries, just sit there looking cool, but do close to nothing for you.

rule of thumb, a 350cid, all stock, no high flow heads, high rise intake and such, look for 600cfm max. get vacume seconddaries so it is idiot proof to boot.

305, try 500 cfms. not gona find alot of 4 barrels that small, but i think rochester made a 475 cfm for the 305 vette motor, so it stands to reason there is probably a marine application for it too.

holly makes a very nice 500cfm 2 barrel, dont know if there is a marine application. you can check to see what mercruiser used on their 5.0 HO engines, chances are, it wil be better than what you have, and there will be a marine application ready to go in a box.

check holly first, they do make marine carbs. if you have to buy mercruiser, it will cost twice as much as it needs to.

need to determine weather you have a 305 or 350 first. it is important.

replace it. just not worth fixing.

 

[xtraham]

Re: 350 CID Carburetor

"replace it. just not worth fixing"

lot's of good info rosco, except for replacing,
carbs just don't go bad, heavy float, dirty, bad needle and seat, yes
out of the hundreds of carbs that I have rebuilt I have only seen a very very few that were not repairable mainly because of a worn throttle shaft, i.e.: taxi's and police cars with a zillion city miles on them.......
I would go with 30 bucks for parts over 250+ bucks for a new carb any day...........