Carb ?

[shirkey4750]

Getting ready to put a new carburator on the boat, 26' Rinker with 350 Chevy and Mercruiser outdrive. Debating whether to go back with Quadrajet or Holley spreadbore. Has anybody ran the Holley? What was the comparison of the two?

[Ryan00TJ]

I've ran a Holley 750 since 92. I replaced the original QJet at that time. I like the Holley much better. It's so simple to work on and tune a caveman could do it. It has dual idle circuits that you can fine tune your idle, re jetting is simple. Everything about it screams simplicity.

[shirkey4750]

Thats why I'm leaning towards the Holley, as I have boxs and boxs of Holley parts on the shelf.

[Speed955]

I just recently did a bunch of stuff to my Merc 260. One of the things I did was changed my Quadrajet to a Holley. Don't get me wrong, Quads are great carbs but I am just more familiar with Holley's. I consulted several carb experts and went with a 600 cfm Holley. The 600 cfm on a small block has incredible throttle response, I did have to fatten up the secondaries a bit but it just flat out screams. I know there will be some that disagree going with a "little" 600 but you would be amazed, I was stunned:D

[BDMar]

When it comes to boats I am almost always a big proponant of going with a larger carb... within reason. And I hate vacuum secondaries on a boat. With that said we have had great luck with the Holley 0-80783C 650 vacuum secondary carb. With a manifold, exhaust, and small cam it works great. It is not a Marine carb and not Coast Guard legal. So I am officially going to tell you to go with the 0-80559. It is a 600 vacuum secondary marine carb. and actually will work better if you don't do any upgrades to your engine other than the carb.
If you don't change your intake you will have to install a square bore plate under the carb to seal it to the spread bore intake. We use Edelbrock part number #2732. It is a thin steel plate and comes with the gasket. Make sure you use the gasket supplied with it between the manifold and the plate. The gasket is a little larger than a standard Holley gasket and seals the plate to the intake. Or put a good alum intake with a square flange on and it will run even better.:D

[TIMINATOR]

Use a performer rpm airgap and a edelbrock 600 or 750 carb. The combo works great. Done it for many customers. While you are in there, a Comp cams 268 or 270 works great too! We have used 280 Comp with thru transom exhaust and its awesome!! TIMINATOR

[shirkey4750]

Thanks everybody just purchased a 650 Holley spreadbore marine carb. Will the airgap manifold perform in an enclosed engine compartment?

[BDMar]

Yes it will. Make sure you get the Performer Air Gap (spread bore) and not the RPM Air Gap (square bore).

[cfm]

We have used 280 Comp with thru transom exhaust and its awesome!! TIMINATOR
Stock manifolds with thru transom ? If no, which manifold or header ?
Thanks.

[spectras only]

CFM , are you looking for ways to brake the 35 mph barrier ;) :D

[cfm]

CFM , are you looking for ways to brake the 35 mph barrier ;) :D
The speed limit went thru so FUGG YEH !!!
I'm not going down without fighting to the end.
As far as the above question, I am just looking for more info for the old data bank ie: grey matter.
I know this cam very well, as do many since it's been out since the Flinstone's, but just not in boats with watered down exhaust systems.
I do have something up my sleave, you'll be one of the first to find out if I follow thru with it.

[tpmarine.com]

The speed limit went thru so FUGG YEH !!!
I'm not going down without fighting to the end.
As far as the above question, I am just looking for more info for the old data bank ie: grey matter.
I know this cam very well, as do many since it's been out since the Flinstone's, but just not in boats with watered down exhaust systems.
I do have something up my sleave, you'll be one of the first to find out if I follow thru with it.
CFM,
I did not know that you lurked on ***boat...:D Hope all is going well, I need to make the time to give you a call to see what you have been up to.
Don B.

[cfm]

Don,
I like Tech sections - it's where you can learn some cool schit. LOL.
Unfortunately, some tech sections are too "i'm right your wrong."
This one seems cool enough. Just as long as no one takes my remarks as 100% we are all set. He,he.
I'm almost always around, call when you want. If I'm awake I'll answer.

[Desert Rat]

Use a performer rpm airgap and a edelbrock 600 or 750 carb. The combo works great. Done it for many customers. While you are in there, a Comp cams 268 or 270 works great too! We have used 280 Comp with thru transom exhaust and its awesome!! TIMINATOR
This is pretty much what I did to mine and felt a noticable difference. I went with the Marine Edelbrock 600 and the 268 cam. Carb is easier to tune IMO then a Holley. You can change metering rods eaiser the Holley jets.

[deeee]

I put one of those holley spread bore carbs on my boat but I had to make 1 inch spacer so the float bowl would clear the thermostat housing. What would I have to change to eliminate that 1inch spacer. Would changing the intake manifold work or can I put different thermostat on.