What is best carb for a crate 350?

A

Aquadzac Captain

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Re: What is best carb for a crate 350?

Thanks for the lookup. Still going with 600 cfm Marine carb with J spill back overflow tubes. I should keep me from blowing up cause I forget to hit the fan sometimes. Right now online I can get new one between $285 or higher and used about $150 or higher rebuilt.<br />Thanks for the assistance.
 
A

Aquadzac Captain

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Re: What is best carb for a crate 350?

Thanks Fishermark, will work on the squarebore adapter after I take the old carb off and double check and then find some wiring diagram to go electric choke. I like the plug and play settings. I am almost done here. Wheww...
 
A

Aquadzac Captain

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Re: What is best carb for a crate 350?

Thanks Fishermark, will work on the squarebore adapter after I take the old carb off and double check and then find some wiring diagram to go electric choke. I like the plug and play settings. I am almost done here. Wheww...
 
bomar76

bomar76

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Re: What is best carb for a crate 350?

Or just forget the whole idea of a choke on it.<br />When we changed the intake manifold to a high rise I totally removed the choke, butterfly, and all associated garbage.<br />Boat starts 1000% percent better w/o it, unless it has sat a week I don't even pump the throttle once to prime. <br />I rarely boat in 20 degree weather;) , so it's good riddance to that thing.<br />Picked up a little on WOT too.<br /><br />But to be a downer, those spread bore to square bore adapters are horrid HP thieves.
 
achris

achris

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Re: What is best carb for a crate 350?

Flashback,<br /><br />The 700cfm is the smallest injection system available, and this is MAX air flow, and since it's injection I don't need to worry about low air flow at low engine speeds not picking up enough fuel, it's injected in. <br /><br />Dunaruna,<br /><br />Supplier in Aust wants an arm and a leg, and your 16 year old daughter phased in over 3 years. It's good to have friends stateside. ;) <br /><br />Aquadzac Capt.<br /><br />Be careful of the Carter/Weber/Edelbrock. I am replacing my Weber because of a problem with fuel leaking/dribbling after the engine is shutdown. None of the manufactures will even acknowledge the problem. I also have 2 other friends here in Perth with the same carb/problem and have found 2 more people on this forum with the problem.<br /><br />Chris..............
 
R

RomanRegal

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Re: What is best carb for a crate 350?

I recently upgraded from a Rochester Quadrajet to an Edlebrock 600 Marine. The carb is a vast inprovement on my 1987 5.7L 350. One thing to watch is that Edlebrock reccomends the use of a ported spacer. The open spacers, squarebore to spreadbore, may allow pooling of gas in the space in the manifold below the carb. This could be the problems some people are having with gas leaking. This recommendations comes from Edlebrock itself. I spoke to a tech and that was the advice he gave me. I hooked up the electric choke, which my previous carb did not have to the coil wire. Good Luck Roman
 
achris

achris

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Re: What is best carb for a crate 350?

Roman (or anybody else),<br /><br />How do I tell if I have a spreadbore or a squarebore? And what's a ported spacer?<br /><br />Chris.............
 
Fishermark

Fishermark

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Re: What is best carb for a crate 350?

As they say, a picture is worth a thousand words. Here is a qudrajet (qjet), or spreadbore carb. Not the small primaries and large secondaries:<br />
quadjet.jpg
<br /><br />Here's a picture of an adapter you may need:<br />
2066.jpg
<br /><br />I say "may need" because some spreadbore intakes have more "meat" on them than others and it is possible a squarebore carb will fit without any vacuum leaks. See how it fits on the manifold.<br /><br />(A squarebore manifold has four even sized holes or a large square opening. A spreadbore manifold has unequal sized holes).
 
M

Mark Bennett

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Re: What is best carb for a crate 350?

AChris,<br /><br />Could you be perculating the fuel out of the bowls due to heat?? Edlebrock has an insulating gasket ($20) about 3/8" thick that is used to help keep the gas from boiling out of the bowls once shut down if you are having a heat or vapor lock condition.<br /><br />Mark
 
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RomanRegal

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Re: What is best carb for a crate 350?

If you look at the picture of the adopter in Fishmarks post, a ported spacer will have 4 distinct andgled ports or holes. The pictures is a open design and not recommended by Edlebrock. Rochesters Quadrajets are spreadbore carbs. If you replace it with a squarebore, you need the adapter. <br />Roman
 
achris

achris

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Re: What is best carb for a crate 350?

Hi guys,<br /><br />Thanks for this info. I'm more 'legs and lectrics' (and outboards), so this is a newish area for me.<br /><br />Chris.........
 
A

Aquadzac Captain

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Re: What is best carb for a crate 350?

ROMAN, I think, like you, I will move from my Rochester 4MV Quadrajet to the Edelbrock 600 cfm for my crate 350. So what I read since I am moving from a spread bore (Rochester 4MV) to a square bore (Edelbrock 600) is an adapter.When you say ported you mean with 4 holes and not the wide open mouth like shown in the uper pictures. Do you recommend new or rebuilt?? A savings of a 100 bucks I believe.
 
flashback

flashback

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Re: What is best carb for a crate 350?

Yep the adapter under my carb looks just like the one in Fishermark's pic.
 
achris

achris

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Re: What is best carb for a crate 350?

Hi all,<br /><br />Just checked my Weber carb and the manifold it's all sitting on. At the moment I am thinking 'Bingo'. I have a spreadbore manifold and a squarebore carb. Could Mercruiser have been so stupid, or am I missing something else? If this cures the problems I can forget the idea of injection and apologize to the carb for calling it so many bad names :) . I will start a new post and let y'all know.<br /><br />Chris....... <br /><br />P.S. Special thanks to Roman for that little nugget of info that has pointed me in the right direction, I hope.
 
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RomanRegal

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Re: What is best carb for a crate 350?

The swap is easy. An adapter, gaskets, and new carb. The ported spacer is sold by Edlebrock. I picked one up at a NAPA store. I never regretted the swap. The carb I bought was brand new. It was a fresh start.<br />Roman<br />There is one other option, if you want to go that way. One could also go and replace the manifold. That would give you a square bolt mounting without the adapter. But, more money!
 
achris

achris

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Re: What is best carb for a crate 350?

Hi Roman,<br /><br />I have sourced and priced an adaptor locally. $50. Cheap enough to try just to see if it makes a difference. Once the engine is running the current carb is superb. I was thinking that all the problems were the carb too, hence the name calling. <br /><br />Many, many thanks for your help, (you have no idea how much this thing has been p***ing me off)<br /><br />Chris.........
 
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