Technical Spreadbore carburetor for 302 Ford, what should I be looking for?

I’ve a spread bore intake for a 302, are there any particular carburetors I should be looking for, or can a quadrajet be set up properly for one?
I had a 350 I pulled from a truck, with an SP2P intake with an edelbrock carburetor on it, and if memory servers it was a spreadbore intake as well, but been so long I can’t really recall.
So many years ago I needed a C6 transmission, found one behind a 400 Ford engine. Guy asked if I could haul the engine away with it. It was still bolted together, it had a SP2P intake and a Holley carburetor on it. (Imagine a person who has had 2 of those intakes in their life ), but I don’t recall if it was a spreadbore intake or not either. But I don’t recall an adapter on either engine.

So, what should I be looking for that will work or can be setup for a 302 ci engine?

Thanks

 

Maybe a picture of the intake would help?

That said, I guess you could run a 650 Quadrajet from a 305 Chevy and be pretty close on fuel mix if you have to have a spreadbore.

 

I can get a pic after I get up ( night shifter) but it’s a Holley street dominator intake. Spread bore with a plenum divider, but not a true “dual plane” intake.

 

It is going to depend on several factors- what year 302 (head changes), cam shaft, exhaust, etc. I agree with @onetrickpony - a 305 Chevy unit should work.

 

I have an old Holley SB that came with my 396, I plan on using it again once the engine is back together. For a GM unit, I would look for something pre-computer over something newer.

 

does it look like these ones I found a pictures of on ebay?



My guess is that you can just add a plate and run a square bore Holley or AFB type carb on it. Like the one that comes with the Edelbrock Performer intakes

https://www.summitracing.com/parts/edl-2732




but that's just a wild**** guess.

I'd hate to see a perfectly good Quadrajet wasted on a Ford motor!

 

4300?
https://en.wikipedia.org/wiki/Autolite_4300_carburetor
Just sayin'. It is a Ford.
Mike

 

Agree, a properly set up Quadrajet is about the best street carb ever. The knockoff Holley, Carter, Autolite, et al spread-bores can be made to work as well.

The thing to remember with randomly mixing and matching carbs is the linkage, fuel lines, choke lines, vacuum and air cleaner will all have to be dealt with individually. Then, there's jetting.

In the H.A.M.B. tradition of paying it forward, I've got a couple of rebuilt Quadrajets on the shelf. If I can determine one would work for your SBF 302" application, you can have it for postage and packaging.

jack vines

 

The Quadrajet was used on a Ford engine as an OEM carb. I believe it was the 429. @Crazy Steve would know for sure.

 

The Ford 4300 spread bore base is not the same as a Qjet, but could probably be made to work on that intake. But they're a pain to get working right, not a very good carb design.

 

Quote squirrel: "I'd hate to see a perfectly good Quadrajet wasted on a Ford motor!" End quote

OUCH!

Ford did use the Q-Jet on a 429.

Ford also used a Carter TQ on a 460.

And in Australia, Ford used a number of TQ's on performance cars.

A consideration would be if you are using an automatic transmission that REQUIRES the special kickdown arm on the carburetor. Thus, if you need it, using the 305 Chevrolet Q-Jet might prove difficult. No issues with a standard transmission.

The Ford 429 Q-Jets are scarce, in demand, and EXPENSIVE!

The Ford 460 TQ is scarce, but only in demand for folks wanting a TQ on a Ford, and not so expensive as the Q-Jet.

Either of the above could be recalibrated for use on the 302. Both are 750 CFM (150 primary/600 variable secondary).

Jon

 

I'll have to have my core guy watch for them. We toss most carbs, because by the time the forty year old carb is pulled from the car by the scrapper, brought to us loose in the back of a truck and dumped in the yard, they often are already busted.

jack vines

 

@carbking , does the suggestion to use a quadrajet from a 305 sbc sound ok?
Any thoughts?

 

Phil - the Ford calibration is going to be different from a Chevrolet calibration.

Virtually ALL Q-Jets produced before 1975 were 750 CFM (150 primary/variable 600 secondary). There were a few 800's and a few 850's (all are scarce).

Q-Jet jets are readily available. SOME Q-Jet rods are available. Q-Jet hangers are available. Re-calibration should NOT be a problem.

As I stated earlier, if one is using a dogmatic transmission, one should determine if the special kickdown arm is required.

So with the CFM and the calibration parts availability, one does not need to search for a 305 carb; physical (arm, fuel inlet, etc.) considerations would be more important.

And anyone even thinking about the consideration of maybe using a Q-Jet should acquire a copy of the book on Q-Jets written by Cliff Ruggles.

Wish he would do one on Carter, I don't have time.

Jack - the dogmatic transmission ones are only expensive; the standard transmission ones are EXPENSIVE!

Jon

 

Don't know of anyone that can make that carburetor run good, including me.
Probably right up there at the top, with the worst carburetor designs.

Bill

 

Ford used the Quadrajet on the '70-71 'plain' 429 CJ motors, primarily for emissions purposes. The SCJ got a Holley, along with a solid-lifter cam and adjustable valve train.

 

That intake will run a square bore carb no problem. You might need a spacer place to get a good seal.

 

Why not just use a Holley 4165 or 4175 spread bore carb.
Both are 650cfm, one is mechanical secondary, the other vacuum secondary.

Bill

 

SP2P intakes are dual plane, small runner, high velocity intakes meant for good low-to-mid-range torque. Especially good for towing, RV, mileage applications. One really woke up my O/T Torino wagon w/ a 351M.
I used a square bore 600 Holley on mine.

 

Mine has a divider casted in the center, kind of an open plenum/dual plane. Will get pic after I get some coffee down me.

 

I appreciate the offer Jack, as was brought up, it would have to have the linkage for the Ford kickdown as I have the C4 for it. I recall now the Holley I have off the 400 with the C6 behind it, did have a linkage for the ford kick down.
Using that Holley might be an easier solution for me
Thanks again

 

If you use the Lokar kickdown cable setup or equivalent, you don't need the lever on the carb.

 

The 302/C4 came from a 70-72 Ford conversion van. I don’t know much about it other than it was drove in and parked, then abandoned.
Anyways, here some pics, and I also found an adapter that should do the trick. I’ll have to check the numbers on the Holley, but I recall it being a 625 or 650 CFM.

 

Summit sells the identical cable set-up for 1/2 the price... and you can use any carb.

 

That’s a neat old intake manifold. I think the Holley you mentioned would be the best bet. I also noticed, that intake has a provision for EGR. Don’t forget to make or buy a block off plate for it.

 

I was (gasp) actually thinking of using an EGR valve.
My understanding is the reintroduction of the exhaust gases cools the charge, allows for some more timing advancement.
It’s ugly like an HEI, but I’m not a “open the hood” type of guy.
FWIW, it’s time I drag up a ‘35 Ford chassis I have out back, get another PU on the road and complete the “de-street rodded” stuff I did some 20 years ago, give the truck its personality back.

 

That Holley in the pictures looks like a 3310, which would be a 750 cfm carb.

 

I remember working on a Chevy wagon late 70s model that was running one of these Holley's. I remember it ran real nice. Could be an option.

 

I’ll have to take my glasses out when cools off and get the numbers. To darn hot out now.

 

I had an ‘80 FBody with I think the same carburetor, but I don’t remember it well enough.