Intake question?

[Anonymous]

I was browsing through summit racing's website and I stumbled upon an offenhauser aluminum intake that they produce and sell brand new for a ford 200. It holds three carbs. but how can this work if the stock head/intake are one casting? are you supposed to mill or cut off the stock inake? I would post a pic but I havent figured out how to yet. any clarification would be greatly appreciated.

Thanks,
Jason

 

[64.5 TX Stang]

You got it, you have to drill two holes in the log for the outboard carbs, then the whole assembly bolts to the log.

 

[powerband]

I was browsing through summit racing's website and I stumbled upon an offenhauser aluminum intake that they produce and sell brand new for a ford 200. It holds three carbs. but how can this work if the stock head/intake are one casting? are you supposed to mill or cut off the stock inake? I would post a pic but I havent figured out how to yet. any clarification would be greatly appreciated.

Thanks,
Jason

Here's the adapter and some typical carbs:

After machine work and installation it looks kinda' like this:

That's the intake side, usually you will see the exhaust worked to match the intake improvement. First step is a port divider for the head and maybe some porting and polishing:

And then a set of Headers to complete the package:

There are many alternatives from mild to all-out performance that are determined totally by YOU.

Powerband 8)

 

[Anonymous]

WOW,

thanks guys very informative.

Powerband,
After doing this modification how much of a difference have you noticed from the popular "large single carb". also how is the port divider being held in place in the exhaust port?

thanks again awsome

 

[powerband]

WOW,

thanks guys very informative.

Powerband,
After doing this modification how much of a difference have you noticed from the popular "large single carb". also how is the port divider being held in place in the exhaust port?

thanks again awsome

Awesome question ! - That is an issue that is narrowly specific to the grateful few who have experimented with both setups on the same "known good" consistent engine. I have been running up an older HiPo 250 that was built with old school techniques and parts including the Offenhauser 3X1 setup. . The initial start and cam run-in was done with a Carter YF 1bbl carb from a 170 with the outer carbs blocked. After consistent tuning I put a progressive linkage Holley/Weber 5200 2bbl with an 2bbl adapter. That added significant performance. I then tried a Holley 7448 350CFM 2bbl and it really kicked up the power. I finally got back to the original 3 - Holley 1904 setup and found the clean rebuilt Holley's were in bad shape. I tried each one individually on my '63 Wagon's faithful 170 and found only one was usable even after "rebuild kits". I started collecting and matching Holley 19xx carbs and found three that work well together. The meager performance of the center carb before the cool "mechanical progressive" outer carbs open up accentuates the effect of the engine screaming towards redline. Translated into - seat o' the pants - when you tromp on it it - it hauls a%$....

The improved flow charecteristics of the multiple ports becomes evident. With the 2bbl synchronous carbs the power comes on earlier and smoother and tops out probably just below the more complicated and $$ Offy setup. I am waiting for delivery of a Holley 500 CFM version 4112 2bblcarb because if the Offy setup improves flow then three 2bbls .... hmmm...

It's a sickness,

Port divider is usually ground to fit carefully and tack welded in but Hooker Header recommends "Interference fit" which I ground even more carefully and use with success in one engine.

Powerband

 

[Anonymous]

Thanks powerband for such a detailed reply. I cant imagine how many hours you spent tuning and changing carbs to achive your results. Its killer!
I have gone through 3 rebuilt holley 2 barrels and havent had success with any of them. As a matter of fact I am driving with a "too rich" air/fuel mixture as we speak. I'll be changing to a weber soon.
I have looked into the offy intake and the word is there is currently an 8 month backorder due to the fact that they discontinued the linkage. So I am patiently, OK impatiently waiting for the new intakes/heads from FSPP to hit the market.

thanks again and yea sickness is a good way to describe it

 

[johnnyzoom]

I think I'm starting to feel a little under the weather.

 

[fxp]

It's a sickness

And judging by the photos powerband you're terminal - congratulations.

 

[Anonymous]

Hey guys, I can't see the pics. Sounds awesome!

 

[Anonymous]

I have gone through 3 rebuilt holley 2 barrels and havent had success with any of them. As a matter of fact I am driving with a "too rich" air/fuel mixture as we speak. I'll be changing to a weber soon.

wsa111 posted details on what you need to do/change to make a 500 work....

If you are just bolting the 4412-500 carb on without going to 68 main jets you are losing much fuel miliage. The restrictors under the power valve should be in the .052-.055 diameter, not the stock .061 diameter. The idle restrictor in the metering block should be in the .030 diameter instead of the stock .034 demenision. The 500 is a great carb but you will lose some power & much fuel economy if not jetted leaner in all areas. Once you have leaned it out then put an 8.5 power valve to prevent a lean condition on transfer from the idle circuit to the main jets

The info should probably be stickied.....these numbers will get you started. The Holley 2-bbl is not really a "bolt on and go" carb!