Offenhauser Intake

I picked up this intake today. There isn’t a solid p/n on it. Does this look like an oddfire intake to you guys? It came with an oddfire cam, gasket set and distributor.

 

No EGR port in the back for a 231.

 

The manifold looks like an Offenhauser Dual Port intake manifold p/n 6035DP. Check it out on Summit website.
https://www.summitracing.com/parts/ofy-6035dp

 

Looks like it but, measure across the flat where it seals to the lifter valley. Should be 7.5". I had one that was 7 1/4" that I think is for a 198.

 

It's for the 225.............

 

I’ll have to measure it up!

 

The intake measures out at 7.5" so it looks like it is for a 225.
Now the question is..... Is the dual port really any better than the older style Offenhauser that I am currently running?
The dual port does have the necessary water temperature ports for EFI sensors, more clearance for HEI distributor, and almost no electrolysis wear.

 

The whole idea of the dual port was to have small high velocity runners for the primaries (on a 4 barrel carb) to help low end torque. That idea isn't going to work with your 2 barrel TBI. I'm assuming your adapter will let air into the primary and secondary ports all the time. It should work fine, you're just not using the concept of the thing.

 

Frankly I wouldn't go through the trouble of swapping them.

 

Your probably correct, but the new intake would clean things up a bit and provides more distributor room.
My main concern would be a decrease in performance due to the true 4 bbl design. I was thinking about milling out a decent portion of the divider.

 

I should probably just plan on yanking my single port intake some day and having my brother tig up the bad electrolysis areas, mill down some material in front for HEI clearance, and tig a bung into it for the water temp.
I have a hard time believing that the dual port would be an improvement over my current setup. The divider looks like more of an airflow obstruction than anything.
Someday when the engine comes out, I plan on having the heads smoothed out and ports matched.

 

From the Offy catalog. Fwiw I run the 360 equa flow. Lots yak on Buick boards about Offy being fos about the dual port design

 

That would be my guess too. I can't see it making much difference if the smaller port isn't all the way to the valve. Ford had a weird 6-port head setup on the 2-valve 3.8 V6's for a while, but it was to have two different runner lengths, not cross sectional areas.

 

I swapped a Holley Street Dominator intake, which is a large open plenum design with just a divider in the middle and put on a Offy Dual Port. I was hoping it would improve low end torque and throttle response but I really don't notice any difference.

 

I'm pretty convinced the small valves negate much intake mods. Ime dual pattern cams help alot.