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Formula29 08-20-2004 11:00 PM

holley or quadrojet
 
I have twin 330 mercruisers, I need to rebuild carb's, I was wandering if going to holleys would be a better choice? if so would a 600c.f.m be big enough?

Airpacker 08-21-2004 06:25 AM

Re: holley or quadrojet
 
The Quads on your motors are a perfect carb for the application. swapping to 600 or so holleys would gain you nothing and cost you plenty. Those q jets can flow big power if the rest of the engine can make use of it. You could use them to make 400hp plus if cammed correctly. Save the bucks and rebuild them, they are simple to do if you can follow the instructions that come with rebuild kits. replace the floats at the same time and whatever you do, DO NOT LOSE the little spring under the primary power piston( the thing with the needles hanging on it. They are a nightmare to get replacements for.

Big Boys Toys 08-21-2004 06:28 AM

Re: holley or quadrojet
 
I would stick with what you have!
Unless you want to start fooling around with new fuel lines, and possibly having to play around with jetting. Holleys are great but do require a considerable amount of tweaking.
Rebuild your existing carb and forget about it!!!!!
Good Luck
Brian

Formula29 08-21-2004 07:40 AM

Re: holley or quadrojet
 
Thanks for the advice, that's all I needed, I will repair the quad's. Thank's for the input!

rob.elliott 08-22-2004 05:03 AM

Re: holley or quadrojet
 
I have quadrajet, which my boat mechanic frequently called quadrajunk. Maybe he was screwed up, but it seemed that it was never set right, either it'd bog down really bad coming out of the hole from too much fuel, or not open up enough to pop out at a reasonable rate. What's up with that??

cig1988 08-22-2004 05:30 AM

Re: holley or quadrojet
 
A major mistake made rebuilding these carbs is the lead plugs in the main body leak and create vacuum leaks. Get some 2 part epoxy and neatly apply over all the lead plugs.

deboatmon 08-23-2004 08:26 AM

Re: holley or quadrojet
 
I've used both. I like the better mid range feel and the improved tuneability of the Holley. More power ? Maybe not at WOT, but maybe at cruising RPM. Just seems a better carb for a boat. Smoother feel all around.

BlueWater1 08-30-2004 01:00 AM

Re: holley or quadrojet
 

Originally Posted by cig1988
A major mistake made rebuilding these carbs is the lead plugs in the main body leak and create vacuum leaks. Get some 2 part epoxy and neatly apply over all the lead plugs.

I am new here .. but how would you know that when you don't even know how to change your engine oil?


Originally Posted by cig1988
I have 365 magnums and was under the impression it was 6 quarts with filter. Changed oil and checked with 5 quarts and dip stick reads full. Boat is on the trailer and is level. Should I put the 6th quart in?

Duh !!

cig1988 08-30-2004 02:52 AM

Re: holley or quadrojet
 
Goes to show you how much you know. If the dip stick was installed incorrectly the level would be low... Post#1? Good start. We all know who you are because you were spotted on the freeway towing your hobie cat with the '82 chevette.

Ted G 08-30-2004 06:59 AM

Re: holley or quadrojet
 
Q-jets are prone to leaks at the bowl plugs under the base. They should be epoxied when you have them off. They are also almost as infinitely tunable as a Holley if you know how. For the bogging problem the secondary air flaps need to be tightened up just enough till the bog goes away, simple to do but lots of people don't know how. Some of the crispiest throttle response I have ever seen has been with a Q-jet. Those that know them love them, everyone else rebuilds their Holleys every year or so :rolleyes:


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