Inliners International Forums General Discussion Engines Triple Carter/holley weber VS 4 Barrel....Thoughts?

When presented with the aluring prospect of using my OFFY triple carb intake with 2 barrel adapters and three carter webers, or the second idea of using a clifford four barrel intake with like a 500 CFM edelbrock, I wont use a holley...I cant bring myself to do it. Anyway, what do you guys think would be better for HP, and torque, and gas mileage, and throttle response. I have heard that 4 barrels are not as good because the carb is farther from the end-ports, and fuel distribution is not as good, supposidly it runs like 15% leaner on the ends, and that the triple corrects this, and is better for all around driveability. Thoughts anyone? by the way I will be using this on a future caddy 261 totaling 285-290 cubic inches, with highly ported/polished cylinder head, clifford hearders, clifford 270 degree cam, .470 lift with high lift intake rockers, enlarged intake/exhaust valves, all balanced with HEI and like 9-1 or 10-1 compression and a 5 speed.

If you run syncronized linkage to all 3 2 barrels it will require plenty of carb tuning and still it might not have the street manners your after.(3 2 barrels is alot of carburation)Alot of guys use progressive linkage and run just on the center carb at cruise. The four barrel would likely be the most practical. I personaly like the look of a few rochester singles on that manifold.

yeah singles are a possibility, but i have seen people here use trip carter weber progressive 2 barrels with much sucess on standard 235 's, im talking about the carter's that tom langdon sells. thoughts anyone?

yeah singles are a possibility, but i have seen people here use trip carter weber progressive 2 barrels with much sucess on standard 235 's, im talking about the carter's that tom langdon sells. thoughts anyone?

There's a guy I met at an Inliner's met from Ohio a few year back,he runs 3 of those Holley-Webers carbs on a modified 261.I never rode in his car,but the guy is very knowledeable and drives long distances in the vehicle.
In my opinion,the central located 4bbl creating a lean mixture on the end cylinders is not necessarily true.I've run a 4bbl on a 261 for many years and now on a 302 GMC for several years.On both engines,there is no indication of a mixture problem.I'm not saying the 4bbl is the ultimate set up,2 or 3 carbs is probably better in some situations,but on a street engine,the 4bbl will function just fine if it's tuned properly.
On my 302 GMC I run a rather small 390 cfm Holley 4bbl.This engine has a cam ,headers,actual 9.5 compression Venolia pistons,small block Chevy V-8 valves and other modifications.The head is not really ported however.For street driving,the small carb seems to giver better response and power up to 4500 rpm.This engine makes an estimated 230-240 hp.The stock 302 head is supposed to have better breathing than a ported 235-261 head,so don't be afraid to run a small carb or carbs,in my opinion anyway.

Dear Mr. Dbane;

The 3 pot manifold with 2bbl adapters is a good idea. I've not done it, but plan to on my 278". As mentioned; there's constant adjustment on the linkage if you "stab it" often, but thats Hot Rod life.

The Clifford with a 390 CFM Holly is good too as you avoid all that adjustment (saving fuel) & only lose a little power.

With $3.00 a gallon gas It's a "toss up". The single 4bbl is probably the cheaper (purchase/operating) choice, all things considered.

How you plan to drive it will be the determining factor I feel.

BTW: Manifold vacuum is equal throughout making the 15% lean (end cyl) a myth.

Good luck.

I got two HWs on a dual Offy and it`s a pain in the a... to keep em syncron.

The Clifford intake with the wide open plenum will distribute more evenly than 2 or 3 carbs that are constantly going out of tune.

Talk to clifford what carb they recomend for your Clifford cam.

just my ct 2, Frank

dbane,

i've got two CARTER/webbers, that i bought from tom langdon, on a 181 ci mercruiser 4-banger. the engine is in my Model A and has a 4-speed behind it. for my money, those carbs are one of the best investments i ever made.....right out of the box, they ran perfect on my homemade, water-heated intake. it'll start no matter how cold, or hot, is very responsive and i think i get excellent mileage, considering i've got quite a bit of work done to the engine. i don't see why 3 of them wouldn't work as nicely on your six........

I use a single 4/barrel on my racing 311" GMC. Technically the GMC and Chevrolets 6's are an odd fire if you count the pulses between the shared intake ports.

The real key to a good running engine with any of the combinations using carbs is a good consistant vacuum signal. I set quite a few records with a single Braswell 2 barrel which flowed over 700 cfm on a tube manifold which was not same length to all ports. I went to the 4/barrel when I figured out how to use a 292 Clifford manifold on a GMC 270 "H" head.

The additional venturis mixed fuel better and the factory taper of the Clifford increased the port velocity at the valve so I made more power. Next I will trying a Precision Engineering hi-rise manifold off a 292 as soon as I'm done with work..

The other key is to warm the manifold by using exhaust or water..Good Luck..#35

If you order your multiple carter/webers from Langdon tell him what they are for and he will jet them right. They are progressive carbs so you can run straight linkage. Last I knew the electric choke model cost around $80.00 each new. Can't get a good performance 4 bbl for that! Four bbls are like Cheby 350 motors, everybody has one.

They are around 230 cfm each. With your motor specs I think a carter/weber tripower would work fine and get respectable milage(as good/better as any 4 bbl). I have the carter/webers for my 225 ci motor.

Well It's a "toss up" with good arguements on both sides.

Those 'modern' 2bbl carbs look like a good deal, running progressive etc.

Is that slant 6 going into the 51??

John, the slant will be in the 51 Ply truck along with a T5 5 speed.

That sounds like a good place/combo.

Keep the other one stock like you made it.

You'll have to post some pics when done.