SBC Engine Intake and Carb Setup Recommendation/Help

Jeez, middle of the second page we finally learn that the carbs & intake must work on one small motor and also on one wicked & nasty motor of undetermined size, cam, head, & RPM.

Do you know what this thread currently lacks??? A fully formed question. Right now all the possible answers, mine included, are shit. When it comes to asking & learning about parts selection, if you can't/won't tell the whole story......just hang a catalog on the wall and throw a dart. It'll be every bit as accurate. In this case you should probably select entirely upon the 2nd motor, and if that's too much for the 305 ask about possible crutches.

Why a guy would try to sort a chassis on a temporary multiple carb setup that's deliberately mismatched is beyond me......

Derek seems to be in the information loop, whatever he says, run with it.

good luck

 

took a performer manifold and ground all the lettering off it and painted it and motor chevy orange with adapter for 2 rochester 2 barrels and stacks. corvette valve covers and late big pipe ramshorns off our stock car painted white. same 10.1 comp as yours. nice tight motor. mallory dual pt. had glass packs. looked bitchin, sounded bitchin, ran bitchen'. 300+ hp 4000-5500....375+ tq 2000-3500.....bitchin! was 3200 lb 56 chevy 350 turbo w/ rv conv...sorry no pics

P.s. was 3.70 gear

 

I'm the one building both motors.


The other motor will be smaller, but of a differnt setup.


And capable of about 4k more RPM than the 305.

 

Gee Shifty, not sure what happened here.

Sometimes folks want to get a little educated on what is out there for induction combinations. Suggestions help point the way. I listen to all of them and pick the ones I like and seem to fit in realism of what im looking for. I already knew what I wanted, I just needed some confirmation.

If someone can learn from this thread during a search cool.

I pound metal all the time - Im just looking for information to help on my motor build; not financial criticism.

 

Nothin looks better then "trips".This is mine, i made my own linkage, works great.Not a great pic, but you get the idea.They also started out as all primaries & i converted over the 2 end ones to secondaries
JimV

 

Don't get me wrong, I love the look of tri-powers and dual quads- I wish i had the $$ to run a setup on my truck..
BUT, I never understand how this works, or why the factories did it in the first place. Even a 400 c.i. motor theoretically only needs something like a 600 cfm carb to operate at 6000 RPM.
So how the hell does a street 327 use 1000 cfm of carburetion??

 

No pissing match or ill will intended, but you're not the only one who's unsure what happened here.

From my angle this started as a question about a multi carb 305 and performance was a concern, then after a few responses you started showing budget concerns because of the economy.

Maybe the root of it is you don't realize the vast differences in a good setup for a strong 305 and a good setup for something that flows twice as much air. Because engines are just air pumps. A good multicarb setup for the 305 would probably be a 30 year old manifold designed around 283s & 327s. And you could get away with some real period (ie small) carburetors. It'd honestly be a great compromise.

That same setup, which we now know must be recycled onto something wicked, will cost a bunch of HP because it's probably got runners smaller than your heads and vintage carbs that lack the kind of tuning ability a real fire breather needs. You may not see the false economy here, but in this case properly setting up around the 305 just cost your new motor 30 horse. When you look at how many horsepower you get for your dollar, that's when false economy comes into play.

Have you ever tried to setup a multicarb vehicle, and tried to make it run smoothly and launch hard?? It's a real process trying to sort out what the carbs are doing versus what the suspension/trans is doing.

Starting to see the catch 22? Select induction around the 305, you leave power on the table with the new motor. Select the induction around the new motor, and you're fighting oversize multicarb 305 issues when you should be refining the chassis setup.

The cherry on top is that a single 4bbl holley, which can be found bolted to an intake for $200, solves all those "temporary setup" problems. Yet you won't do it because of the style penalty of a single 4bbl, even though it's temporary.

Sorry but your whole thought process just doesn't make sense. You asked for advice about setup and that's my advice like it or not. You're asking the wrong question.

Good luck either way. 55 chevy gassers are cool, you've got good taste in cars plus Derek in your corner, it'll turn out great.

 

so your camel humbs heads are going to give you around 10.25 to 1 comp ratio if your running flat top pistons, i would think you would run a long duration cam to allow for pump gas to be run, run a small tunnel ram.

 

Gassers are about power, if not true power then visual, a three deuce doesn't belong on a gasser but a four deuce or dual quad does as far as visual goes.
Why are you building a complete 305 to test with, just get a used 350, hp will probably be more anyhow. If you are trying to setup the chassis on the car you don't need to be worrying about setting up the motor with multi carbs too. Dial your chassis in then drop the new bullet in and dial that, besides if the car ran 11's it's got to be pretty close anyhow.

 

Hi
and thanks for options ive built a few Sb chevys. You cant beat
the old 4GC rochester 4 barrel on the straitway ,not smogless thou.
Get you a race cam 268 o duration 48.oo lift.... put an advance distributor weight adjustble kit into your distributor,.A set of champion spark plugs .. duel exhaust ( most any large factory muffler)..
run small 14 tires and high 3s diferentual gearing ,get ready to get rubber .... as for the spending on the duel carbs its a loosing proposition
youl end up jerking it off. The factory 60s cast manifold is fine for this arrangment , unless u try the quadrajet 500 cfm 327 carb and manifold
youl have to set the secondary auxillary to the best torque want
smoother idle get rhoads lifters...

 

Run one of these . . .

 

Interesting, and were do you purpose he get one?

 

Yeah, where do we get one?

 

for your motor, looks cool.......sucks alot

 

This an old Inglese weber intake - they don't make them anymore so you're stuck with eBay and any other classifieds you can find.

Steve

 

A 305 V8 in a 55 chevy gasser and with 3x2 or a 4x2 intake set up? you must be building a show car for sure with that there 305 and 3x2 or a 4x2 jar set up. Your better off with a 265, 283, 327 or even a 350 csb with that there cross ram with holley's hell run a rig runner, just just don't see too manny 55 chevy gasser's out there with 3x2, 4x2, 6x2, or 8x2 jars on there intake's. But if you building it just for a looker that would work for you. GOOD luck on that there build of yours.

 

a stock 305 would flood out with 2-4's

Nope, still getting it wrong.

D'ya think having no idea what a carburetor does might prevent someone from offering an opinion?
Evidently not.

 

I suppose since im running a 305, the car is a pile of crap and should be set 'a-fire' if you ask a few people around here.

All I wanted was some honest information, not "car bashing"; "get a real engine"; "your wasting your time" isses to have to wade through. (Stupid Drama)

At any rate: Thanks for all the information, most was great and informative. - got the car to fire w/ the intake shown below It roars like an animal. Im sure I will be having to play with the jetting; but may work out well with stock ones.

Had my buddy over; who raced in the 60's building slingshots and other altered chassis. Got alot of 'kudos' on the build and overall looks - he said i hit it close on the vintage look.

This is what I have been building for the past month; straight axle and all. (im not interested in the whole "straight axles dont make gassers" comments; keep them to yourself - this is the way I wanted to build my car)

Have to fine tune it and work out some bugs to break it in.

 

That intake/carb/valvecover setup is beautiful. Cool car.

 

Cross ram would be a BAD idea, the plenums are WAY too big, i dont even know if i can efficently run one on my almost race 302 chev, but i'm gunna find out

 

Who the hell made that???

 

Mr. Haney---i have 3-2,s on a 350/ with trick floe heads---lunati-504 hyd. Cam--at 60 it poof,s out the exhaust---i tried everything--can u help