4 Barrel Carb on a straight six?

[TwoFiftyShifter]

I have a 230 I6 in my GMC, and it runs really well. I plan on keeping it in there for the time being. I have an Offenhauser 4 barrel intake/exhaust manifold sitting around, and was wondering if, besides the cool factor of a 4 barrel on a six, would it yield any performance?

[Joey~AP]

I had a racin buddy that had a strait 6 in his street stock. It would run circles around the cars in the Stock Car class....that werent anywheres close to stock!

As far as I new....he had an Offy, Holley 4 bbl, cam and headers.

I dont think just a carb change would help.

They all need to be compatible.....flow wise.

Make sence?

[fixie]

Once apon a time looooong ago (yes im oldder) I used to drag race with a fella who allways ran inlines some not to stock and some where close to stock. He could take on most small blocks and do fairlly well. he would run a small cam and the offy with a carter carb tuned down with smaller jets and vacume secondarys. Not that hard to do with our trucks. You can just run the mannifold and carb if you want to play with the tune up. Also you might want to run a little more timing. The more you do the more you will learn. So bolt it up and have some fun they aint gunna make any more of um.

[MacAttack]

If you’re willing to match the other horsepower determining components to the carburetor it would be well worth the effort, but if it’s just for ‘the look’, you’ll just be shoving raw gas out the tail-pipe when you tromp on the throttle.

[Heater63]

Heck yes put it on; or sell it to me. You will need HEI and Headers to make it work well though.

Read Clifford Engineering, Inliners.org site, google Leo Santucci; his book tells how to hot rod a L6 all the way up to your money runs out.

[ol Curt]

If you put a Holley 390cfm it is progressive...i.e. you are only using two barrels till you get into it. Headers, RV cam, offy or clifford intake and the carb will make a difference performance wise. Clifford intake for drag racing, the offy for street performance.
However, because of the way the heads are made on the old inlines, you might want to consider having some head work...lump ports, polishing and porting, etc to make it flow better. If the high performance is really important, in addition to the head work I would think about three single or two barrel carbs. They do a better job of equally supplying fuel to all cylinders if you get them all in sync.

[vin63]

I ran a Holley 390 cfm carb atop an Offy intake on my L6 in my '63 Chevy II for many years, including drag racing it. It was the best performance modification I made to the L6 because that 4bbl carb was so much more efficient than the single-barrel Rochester. For daily driving purposes, I really only used the first two barrels and I would get 20+ mpg on the freeway with a PowerGlide. I broke the pinion shaft on my rear end twice after the induction install (intake, carb and headers), so I ended up putting in a Ford 9-inch.