Holley difference?
 

What's the difference between a street Holley and a marine Holley besides the j tubes and vacuum ports?

I belive everything is redisigned ( grooved and bushed throttle shaft, J-vents ect. ) so fuel cant leak into the engine compartment

shouldnt you be working ???:lolhit::evilb:

I have researched this much myself and the only real difference I could find was the j-tubes. When you look at all the spec on both I can't ever seem to find any difference. I do know the j-tubes can be easily converted to a street carb. As you know if the Coast Guard sees the straight tubes you will be ticketed more than likely. I could easily be missing something here however I have rebuilt several of each and yet to find any difference in the internal components. I have also run holley street carbs on marine applications and noticed absolutely no diff. Some models use a different float system for marine carbs also perhaps due to the rougher environments. Hope this helps. Basically the j-tubes just keep any excess fuel back into the carb.

"USCG approved" and holleys already have a habit of causing fires from leaks in the pump diaphram.
Dont even think of using or coverting a car carb, you never know what the insurance Co might do if something bad happens.

Ok how about opinions between Holley and Edlebrock carbs?

Limited to 750 cfm by Eldelbrock.

i love edlebrock carb they dont seem as tempermental as a holly. on the other hand holly is designed for straight hall ass and in my opinion would be the best for a boat considerin the application and constant high rpms, what i sayin is if you have a race car put a holly on it, if you have a street strip cruiser put an edlebrock on it. and by the way i have auto mtive holly 750s in my boat and love them.

What's the application?
Keep in mind the Edwlbrock = Carter AFB = Weber used by Merc on their last carbed motors up to the 410hp, 502.
You can find used Webers for under $100 easily.

J-tubes and jetted up slightly for the most part....as far as the edelbrocks, as other said good std cruising carbs, use a pair of 600's on my 454's, they never see over 3800, and they work great, but for real performance holleys are much better...

I'm building a 383 for my 23' wellcraft I tend to take it easy on my stuff, I like to run without breaking if I can. I know lots of people with big fast boats so I'm tempted to keep up every now and then.

So you're certainly under 400hp......
If it's a budget issue and your not running too big of a cam or after the last 20hp at 5500rpm, go with the Weber off a Merc BBC (under $100). It will probably be jetted ok as is. The only thing you might have to fab/modify is an inverted flare fuel line. Although one from a Merc 260 SBC motor might work.
A Merc Qjet from a 330/365hp Merc would work for that too and are generally better at starting and idle.

I hope to be right at or just under 400hp. I'm running a fairly high compression ratio for a marine engine just over 10 to 1 and a cam that's going to want as much dry exhaust as I can give it.

Well Merc used the Webers on their 410hp 502s, so they'll flow in that range, and Qjets were used up to 370hp motors. Both are about 750cfm. So like I said, you might gain a few hp by going to a 800+ cfm Holley if you honestly think you'll be pushing 400hp, not sure if that would translate into even 1 mph more.
But since this is the "Budget" section, I'm going to guess that used marine Webers will be a lot cheaper and easier to find than marine Holleys.

What cam are you running and what heads are on there? I ran a RPM intake with a JET mod'd merc QJet and pull 436 Hp on the dyno. If you want to run a Qjet that is setup well for the 383 power curve in a boat let me know, I want to get rid of it. I have a pro systems carb on a single plane intake now, pulling just under 500hp.

The Weber Merc Carb 750 CFM is good to 550 hp. I believe he rates the 750 qjet good to 475 hp. The 750 Vac Secondary Holley is good from 400-550 and the 800 vac for 500+. This is out of Dennis Moores book "BB Marine Performance".

I'm going to be running a 750 weber on my 439 bbc. IMO a 750 on a 383 is going to be too big. 650 would be a good size for that motor.

I have a 750cfm holley on my 355,runs sweet! :)

here you be the judge

http://www.youtube.com/watch?v=I78vehnSmF8

nice !you are set up real good .i would copy your set up in a heart beat .how fast do you go???

fixx
 

in that vid lower 70's,,the boat throws you around a bit and its hard to read the gps at times..i dont have a recall on mine

mind you all the power is going through a volvo 280 drive..

Be real simple to email Holley for an answer.
http://www.holley.com/TechService/TechRequest.asp

put a Hp Holley or a 4779 on it,Garry Williams here sell the j tubes,run a flame arrestor ,only prob is if the needle and seat sticks,ck the prices of the street Barry Grants, might be real close to Holley

Where do I find this Garry Williams? I would like to pick up several sets of the J tubes?

Here's a place you can get the J-tubes. I got a set and converted a street 850 DP and it works great. Part number 85-453. $7.59 each. Besides the J-tubes Holley advertises that their marine carbs have the fuel metering system calibrated for a boats unique engine load.
http://www.carburetion.com/parts.htm

601-939-5861. located in Florence, Ms. tell him Rob Stringer sent ya.


He's dry and short.Pat Musi uses him a good bit,

I would contact patrick at pro systems

Gary Williams = Best carb guy ever!!!
Run one of his carbs on my drag car , never had to touch it .
Tell him what you have and what your doing with it and he will custom make the perfect set up for your app.

I second Pro Systems. That guy knows how to set up a carb.