4 barrel Carb question

[suburban99]

1972 k10 350/350. Currently has a quadrajet 4 barrel and runs ok.
Truck has 33x9.5 x15 skinnies and gets about 14mpg. I plan to keep the 350 as its recently (1500 mile) rebuilt and add a 700r4. Should I keep the quadrajet or switch to an edelbrock? Had an edelbrock on my 304 CJ and was quite happy with it...or should I go right to TBI?

[cleszkie]

Keep the Quadrajet until you have the means to install a TBI system. I would steer away from the Edelbrock, especially if your Quad is currently working good for you, which it sounds like it is.

[davepl]

If you've got a Q-Jet and it's running well, they run (almost) as nicely as EFI when properly calibrated, so enjoy and ignore! I wouldn't poke that dog with a stick, as they say...

[Wide Open]

What has you saying it runs ok versus the Edelbrock running good on the Jeep?

I've always liked the quadrajets better than the Edelbrock's for mostly stock applications (drivability) and a Holley or derivative for high performance applications.

[Alex V.]

Yep, if your Q-jet is in good tune keep it. About the only thing an Edelbrock or Holley do better than a Q-jet is pour fuel in mass - and the Quadrajet is no slouch at that if the secondaries are working right. They are rated at 750-800 CFM, after all.

[truckster]

Quadrajet. I would spend money on a quality remanufactured Quadrajet before I'd buy a new Edelbrock. And I've owned and worked on Edelbrock, Carter, Weber, Holley (and Motorcraft).

[CCCC]

Please pardon the piggyback here, but this thread is very timely for an issue I'm having with an Edelbrock (1904) version of the Quadrajet on a '71 350 ci.. It simply started overflowing/flooding at idle and two good dismantle/check/adjust efforts have failed to fix - made it worse actually - fuel now coming out the vent. I'm going to rebuild it with a new kit, but in the meantime am thinking about buying a replacement.

What vendor (online?) do you recommend for purchase of a rebuilt Q'jet - who has the best product/guarantee? I am thinking of going to the later version (1980s) with electric choke, assuming it comes calibrated for the older SB350. Would like to retain the same fuel inlet/filter arragement. Do you see any possible problems there?

Thanks for any info/advice.

[jr1000yarder]

http://www.customrebuiltcarbs.com

Really good people and I'm sure Phil has the right # for your truck in stock

Just my .02

[CCCC]

Originally Posted by jr1000yarder

http://www.customrebuiltcarbs.com

Really good people and I'm sure Phil has the right # for your truck in stock

Just my .02

Thanks. Just sent him an inquiry.

Any other reccs folks?

[Gromit]

Sorry to spoil the party; but I have to offer my own opinion for those willing to stray from the OEM path and that is for the Quickfuel Slayer 600 CFM Vacuum Secondary four barrel. SL-600-VS

It is about $318 complete from Summit or Jegs or maybe even Quickfuel direct

http://www.quickfueltechnology.com/c...600cfm-vs.html

The vacuum secondary makes it very forgiving and somewhat self-adjusting compared to say a 750 CFM mechanical secondary Holley with the fiddly four corner idle mixture settings.

It is all aluminum (instead of weaker zinc) has the clear sight windows for setting the floats; all parts are available individually and at a reasonable price; full rebuild kits are cheap, and the killer app is their vacuum secondary rate is adjustable with a screwdriver - just 1/8th turn of a screw and it is like swapping out a spring on the Holleys and clones..

[CCCC]

Thanks Gromit - this is interesting. Went to their site and couldn't find much detailed info on overall bore setup and choke type - maybe I didn't seek very well. Do you know if it is square or spread bore and if it comes with electric choke?

[Gromit]

It is square bore, and I do have a spreadbore manifold but I found I needed a carb spacer anyway to have clearance for the vacuum hose to my brake booster and PCV vacuum hoses.

So I used a Mr. Gasket spacer that also functions as a spread bore to square bore adaptor with the SL-600-VS carburetor.

The adaptor was $32 from Oreilly's (photo attached). Item # MRG 1932

QuickFuel and Edelbrock and Moroso also sell similar ones.

Yes, it has an electric choke - just one wire to run to the fuse block "Ignition Unfused" terminal (key on power) - I used an in-line fuse - $3.00 from Oreillys.

Mine worked out of the box with no choke adjustment necessary.

[CCCC]

Thanks, Gromit.

[CCCC]

Originally Posted by jr1000yarder

http://www.customrebuiltcarbs.com
Really good people and I'm sure Phil has the right # for your truck in stock
Just my .02

Got reply this AM - he will sell the rebuilt ED 1904 with ethanol-proof components, electric choke and calibrated for older 350 - says will bolt on with no hassles - for about $400 plus S&H. Sounds like a good guy. Thoughts?

[leftybass209]

I think everyone above pretty well covered the topic, but to lend my opinion-

The Edelbrock carb in and of itself is negligible as to how much fuel it would save you over a well tuned Quadrajet, or how much performance it could offer. For every post I've seen where someone says they saved fuel, I've seen one where people claim it was a waste of money.

I have an Eddy 1406 on my crate 350, backed by a 700r4, and i'm certainly not sipping gas. The Edelbrock isn't just a bolt on carb for most people. It is very sensitive to fuel pressure, usually requiring a regulator or an Edelbrock fuel pump that can consistently put out pressures below 6psi. Also, they are sensitive to heat and can experience carb boil/vapor lock issues, so often they need an insulator gasket and/or a phenolic carb spacer. So that $xxx.xx priced Edelbrock carb often needs to be coupled with new fuel lines, pump, and carb spacer. The Quadrajet however, can be rebuilt for under the base price of the Edelbrock, and still offer equivalent performance and fuel economy.

I think it's important to note that once you factor in the cost of the entire transmission swap and whatever carb or fuel delivery system you choose, you'll have to put thousands of miles on your truck, just to break even on the amount of fuel you'll save. With an OD transmission, You'll only start to save gas in 4th gear. Being super generous and optimistic, you may gain 5-7mpg over an equally tuned vehicle not using overdrive, using hyperdrive characteristics. That's A LOT of 4th gear driving mileage to recooperate the cost of the transmission and fuel delivery system.

The swaps you are considering are best justified for personal enjoyment, and the benefits of going EFI over carb (ease of starting, elevation driving etc.)

Best of luck with your decision!