intake info? dual quads or keep it simple?

So I have a 54 chevy that we setup for a v8/open driveline conversion. I was on the fence for sometime about doing a crate motor or a rebuild. I went the rebuild route because I like old parts and why not get dirty. The motor is a 1969 300 hp sbc.The tranny I plan to run is a turbo 400 in front of a 57 rearend.

So i got to talking to a customer of mine this week and he says I have just what you need. I just want my car to be a cruiser. I dont have much engine knowledge and have heard that multiple carbs can be a pain. The guy says it is a stock manifold from a 57 vette. What do you guys think i should run?

 

Pain free cruiser? I'd go with a stock 4bbl. intake and carburetor! Dual quads are sexy, but a PIA.

 

if you realy want just a cruiser go with a single carb. multi carbs are cool, but are touchy. once set up they are fairly reliable, but you have to enjoy constant tinkering.

 

Exactly. Easy to over-carb with multiple carbs. Smallest 4-barrels are about 390 CFM = almost 800 CFM total. Getting the idle set right is sometimes an issue. Getting certain (end) cylinders to starve can be a problem depending on the location of the first two barrels that supply gas/air.

But they look cool. If I was to run them I'd use the smallest QuadraJets I could find and hook up both carbs primaries at once, to promote even gas/air mix in all cylinders. This all depends on the manifold, etc.

 

Me: 2-4's 390cfm each...straight linkage...no starving cylinders...nice throttle respose...fuck the mileage...its a hot rod. (cam profile fyi: intake lift: .442 exh lift: .465, duration @.050: Intake: .214, exhaust: .224, lobe center: 112 degrees)

 

Just a cruiser,single 4-barrel-------bad ass cruiser 2-4-barrels

 

Not many are running the old style 2x4 manifolds on any brand motor......so.....I'd run it in a heartbeat.

what the worst that can happen?..end of the world?

 

Multiple carbs=multiple problems. Tinkering cuts into your cruising time.

 

Well, the intake you picture in your post came from the factory with a pair of Carter WCFBs on it and, although the front carb didn't have a choke, both carbs had mixture screws, so it stands to reason that you could scare up two WCFBs from 283-327s and make them work. Don't think about a pair of the easier to find 4GC Rochesters, though....they run into each other when you try to bolt them on.

 

Better look into finding the carbs that will fit that intake. That would be my first move, then see if it's worth the out lay to impress your buddies when you pop the hood.
That intake also requires a small distributor cap to clear the rear carb, something else if you don't have one.
Myself I run a mild sbc with two 600 cfm Carters on straight linkage for the past couple years, don't really mess with it much.

 

I ran the same setup back in 68 on a low horse stock 283/4 speed 64 Malibu SS for a year. I was 17 and barely had the skills to put it on and get the distributor back in. The car before that was a 56 Belair 2dr ht with a 348 Tripower.

40+ years later I still have multi carb cars.two 3x2 and one 2x2...and a spare 348 w/3x2

Go buy that thing

 

I had the same decision a couple months back. Same intake as yours. I sold it to pay for a good set of '461 heads. I later picked up a Edelbrock C4B and TM1 Tarantula. Gonna go that route.

 

--------------------
Ditto on that. If it's a 'cruiser' and not a
true "the only vehicle I've got, daily driver",
go with the early 'Vette intake and a pair
of small quads. Don't be scared of it either.
Remember that that same intake set-up
was considered 'tractable' and 'user-friendly'
enough that Chevy offered it as an option
on regular passenger cars in '56 and '57,
not just on the 'semi-exotic for the time'
Corvette.

Mart3406
=========================

 

Dual quads with a progressive linkage (which I recommend for the street) is a pretty easy set-up. I know, I've installed 'em on cars for 45 years and my Buick's got the factory set-up which has been trouble free outside of normal carburetor maintenance.

BTW, that dual-quad set up was also fitted to 265s!

Heathen's right that the manifold originally had WCFB 4Bbls, but a set of small Carter AFBs should fit OK.

If you run the dual-quads, you may want to consider a slightly hotter street cam that'll still work with the TH400's torque converter, as you will have a lot of intake capacity - this has been mentioned in other posts. Also, it's advisable to install a set of headers and low-restriction zorst to make the most of the induction system. I'm sure you'll like the added performance the multi-carb arrangement offers.

Hope all this helps.

 

I had a stock 1956 Chevy with the factory 2X4 set-up when I was 17.. No problems and it ran just fine!

 

you better check the price of those two carbs that manifold takes. you could easy have $2500 or more in just the carbs and linkage.

i would go with the single 4 my self.

 

2 carbs = Twice as much time in the shop

 

I have had a few cars with 2X4's and really had no problems and the last set, about a year ago got 20 mpg on the hwy, Really! It was a light coupe and had 2.73 gears. Out of all the multi carb setups 2X4's are the easiest to deal with, at least it has been that way for me. The 36 SD I am building now has a 283 with an old Corvette 2X4 setup on it and that's what it will run!

 

^I'll agree with you on a point, Toast. If you're going to go multi carb 2x4's is better than running 4x2's....or more.

 

On a closed hood car, I vote for everything as simple and reliable as possible

 

Yep, 4x2's are probably the hardest, at least the side by side type, you have to run all 4 at the same time and sync the setup. 6x2's you "can" run the center 2.

 

You'll want to check into getting the carbs. I think only the WCFB's fit and they are not all the same.

 

A bit OT, but just to comment about the 4x2 set up (Man-A-Fre and similar) or 6x2s (linked or progressive), you need to get one of these handy devices:


I've had one in my toolbox for over 40 years and have used it to tune countless multi-carb set ups. At one stage, there was a 4 Bbl version available for those running linked dual-quads.

 

You can get good reliability and decent fuel mileage with either a single or dual carb setup.

One issue with the manifold you picture is the throttle bores are closer together from side to side than non-WCFB carbs by 1/4 inch.

If it were me (and I have set up LOTS of these), I would put two Carter AFB 400 CFM carbs (part number 9400s or 9410s - you can mix or match) on a pair of the 1/4 inch fiber spacers from the 1950's. You have to machine an 1/8 from each side of the throttle bores for clearance. Run solid linkage. Use chokes on both, and idle on both. Extremely reliable. Set it up and forget it except when you open the hood to show.

Jon.

 

I had bought a carb sync for my 2x4 TR setup (pair of holley 650dp's) and it came with different sized adaptors that went up to 5 1/8". You could actual make one with a carb cap put a hole in it then mount uni-sync (like above) on to it. I had ran single 4 setups for years and going to the shows things started looking the same so after an engine refresh decided to go with the multiple carb look. It did take a little more work (mine set crossways see photo album) and with the TR setup liked more initial advance and need a couple extra minutes to warm up it was worth the effort and hey we are hotrodders right?

 

Heres whats in my 50 Chevy sedan delivery cruiser. Not a minutes trouble and way cooler than one carb.

 

The Uni-Syn is still availible form Edelbrock. My Dad told me to never run multiple carbs without one, which is odd, because he never ran multiple carbs, but a guy in his car club had a three deuce set up on a flatty in '58 or '59.

The choice is yours, of course, but that manifold might be good for trading later.

 

The Uni-Syn is a helpful tool in synchronizing multiple carbs when solid linkage is used. It is not used for dual quads with progressive linkage (primary carb, secondary carb) or tripower with progressive linkage (center carb primary with the two ends secondary).

And while useful, most of us old-timers learned to do the synchonization listening to the sound of the carburetors with a home-made stethescope (a piece of vacuum hose).

Jon.

 

wow guys i am floored by everyones responses. I picked out a polished alum. intake with 1 single 4. As far as I can tell from my research i came from 265/283 sbc corvette. my motor is a 350 thanks again

 

No factory aluminum 4bbl intakes for 265/283s. The first one came on the '62 340hp 327. What is the casting number directly behind the carb mount?