Offenhauser Dual Quad intake......

[61belairbubbletop]

I've been looking all over, and can not find a Offenhauser HIGH RISE Dual Quad
intake manifold for my 333 heads.

There was a LOW RISE Offy on ebay yesterday morning for $200 (buy it now)
but I passed, cause I'd rather have a HIGH RISE, (Plenty of room under 38
Ford hood).

I'm beginning to think maybe I should have bought it !

Can someone please advise me on where to go ?

Thanx,

Randy

 

[models916]

Summitracing Has 3 Versions

THY HERE

http://store.summitracing.com/egnse...6+4294840094+4294888960+4294925239+115+400429

 

[Nuts]

Will this help ???

Don't mean to hijack this thread but I've got a question ??

Models,

I'm currently running a modified factory 2X4 manifold on my 409 with 817 heads. I just can't seem to get everything running right and wonder if one of these might work better with my setup. She was running very rich with both carbs (Eldb 500's) working together, I changed to a progressive linkage and got the O2 down where it should be but now it has flat spots and just doesn't run right. : From the description, it sounds like each carb would be feeding separate cylinders with this setup. Would that be better and easier to tune ?

 

[models916]

ports of call

At least the ports would line up. If you don't match port the heads with Chevy intake I would think you would get some puddling at lower rpm. I run 2x4 600 cfm Edelbrocks with solid front linkage and vac. secondarys. Single choke on rear carb. No flat spots anywhere, great idle even in gear as low as 800 rpm. I can stomp on the pedal and just smoke 'em up. I have the high version, but It would look more original with the low and stock air cleaner. If I had to do over, I would use the low version and tune the setup with spacers. Tall version just fits under the hood with .25" spacer/gasket and air cleaners. I had a big port single intake with 750 Holley on mine originally and it ran poorly at all RPM.

 

[rstreet]

I am running the low 2 X 4 Offy with 500's and progressive with great results. I believe that is due to the port match of the Offy. How about jetting/rods(too aggressive?)

 

[Nuts]

More Questions ???

rstreet,

What are you using for an air cleaner ? I see that the carb spacing is about 1" different for the Offy manifold. Do you have a picture ???

 

[TomO]

While talking with my future engine builder about my 472/409 project he said to use the low rise offy with 2/500s. I will be using 340hp heads (817's).
Tom

 

[MileHiSS]

I bought a high rise last month from Show Cars. I have a low rise also, but I'm waiting to check hood clearance before I sell it.

 

[rstreet]

Nuts. Yes I have pictures that I can send because I am not sure how to post them here. Anyway I am using two small chrome cleaners until I can find a cast oval that fits to Offy. Someone is getting ready to cast them soon I was reading. The linkage was a piece of cake and the fuel line was easy once I solved the filter problem

 

[Nuts]

Pictures Please

rstreet,

Please do send me picture if you can. to Mr-Nuts@cableone.net

Thanks

 

[models916]

hood clearance

Lots of hood clearance with the high-rise offy.

 

[SS425HP]

Nice engine bay

That sure is a nice clean engine bay. I like the fuel lines. And, the breathers on the valve covers. Nice, clean installation.

 

[rstreet]

Nuts pictures

Nuts.....
I sent the pictures of my 2X4 set up while up here in Jim SS 409 territory(toronto) so you should get them. Let me know if you didn't.
I forgot to tell you that if you go with the Offy manifold you will need to get a set of ss 12 point intake bolts from ARP p/n435-2101. This set includes the small headed bolts needed but more important includes 4 very small headed bolts for the divided runner area bolts....Looks good but I don't remember if the pictures show them

 

[dq409]

Don't mean to hijack this thread but I've got a question ??

Models,

I'm currently running a modified factory 2X4 manifold on my 409 with 817 heads. I just can't seem to get everything running right and wonder if one of these might work better with my setup. She was running very rich with both carbs (Eldb 500's) working together, I changed to a progressive linkage and got the O2 down where it should be but now it has flat spots and just doesn't run right. : From the description, it sounds like each carb would be feeding separate cylinders with this setup. Would that be better and easier to tune ?

Nuts, I would go back to solid linkage and rejet or change the meter rods to lean up the carbs.
Then adjust the idle circuit on both carbs.
I believe doing it this way gives a smother idle and better reaction off idle.

As far as eiser tuning once you get the jetting right the tuning is a snap.
just like tuning one carb but with two.

That is,,, tune one carb at a time the same way you would adjust any carb.

By just changing the linkage you did nothing to address the running rich problem.

Also those of you running the two small air cleaners you don`t have enough air filter surfice for your engines. I would use the K & N type filter for a little more air flow.
Even then you will have some restriction but it is about all you can do if you are running those types of filters,,,

Good luck, dq