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I literally just picked up an Edmunds 2x2bbl intake for my 52 on ebay. I should be getting it sometime next week. If anyone out there is interested I can "review" the intake and do my best to "science it out" explaining obvious strengths and weaknesses, take measurements and add pictures and possibly videos. To the best of my knowledge no one has done that yet. If enough people show interest I'll get the information out there.

I would enjoy seeing the setup. My favorite mechanic here in town has a 51 Hudson with the twin carb setup, so if you need comparison photos it, let me know and I'll post some.

I'm interested as well. I've got a foundry and would like to have as much info as possible about these and other performance parts for flatheads...Packard, dodge, chrysler, and Hudson.

I have a twin H Hudson intake as well no carbs though so I could give comparison measurements and pictures. I'll let you guys know when I get it in the mail.

The seller sent out the manifold so I should be receiving it around Wednesday.

The intake arrived its in great shape. Is there any specific information anyone wants or do you just want me to do a general overview of it?

I'd like to hear your overall impressions. But I am curious about the size of the plenum and how that would affect performance, and if the two plenums are somehow connected/ballanced.

Thanks for working on this.

Overall impressions are pretty good. As way as vintage speed equipment goes its not a bad design, I have seen far worse over the years.
Keep in mind Edmunds from what I understand was a more "low end" performance company (in regards to their contemporary's many of who are still in business) and tended to be a one size fits all design so this intake to a comparable L8, Buick, Olds, Pontiac, Edmunds intake is likely very similar.
The heads they produced all had an identical combustion chamber style not saying that is a bad thing just the nature of the company.
It is a LOT heavier than I expected, not near as heavy as a cast iron intake but I was suprised. The top of mine was polished at one point but the bottom was left as cast. I don't know if this was done by Edmunds or a previous owner.
The ports are fairly roughly cast and I don't see any evidence of previous porting but it seems there is enough meat to do some light polishing if you wanted but their are some blind corners, specifically the front and rear runners so unless you went with extrude honing would never get it all smooth.

OK now the meat and potatoes part
The ports are round just like the ports in the block and measure 1 5/8 diameter.

The carbs are 6 1/2 inches apart as measured center to center on the opening for the butterflies.

The holes for the butterflies are 1 3/8 inches.

The floor of the manifold is stepped, not like a dual plane intake but the plenum seems to be on the same level but it steps down as it goes into the runners.

From the carb mounting flange to the highest point on the floor of the intake varies from 3 3/8 to 3 1/2 I think this is due to some fairly rough casting.

The lower portion seems to be about 4-4 1/8 deep but its difficult to get a good measurement.

the preheating line that looks as though it would tap into the cars heater line is 1/2 inch inside diameter and it only runs along the outside of the the intake.

The plenum seems to be divided from left to right as in the drivers side carb venturi feed the 3,4,5,6 cylinders and the passenger side venturis feed the 1,2,7,8 cylinders.

The inner runners (3,4,5,6) look as though they should tie into the outer (1,2,7,8) but using a flash light with the lights off I cant see any light coming out of the outer runners. The intake is still in its as delivered state so maybe their is some blockage in the ports.

The front and rear runners are close to 13 inches long from the center of the carb flange to the end of the port as measured outside the intake. My tape measure (the best of all calibrated instruments) will go all the way through the ports on the outside and the measurement is pretty close to the same

The inner runners are a straight shot from the plenum under the carb and are 4 5/8 inches from the end of the port to the center of the venturi and 5 1/2 inches to the divider in the plenum.

There is what seems to be original 1/2 inch "vacuum" line in the riser under the rear carb mine has a pipe plug in it and I don't know that I will be able to get it out easily. and it has another one on the forward runner 3/8 inch in diameter just forward of the "Edmunds" script. I have never seen one here in any of the pictures I have seen of these and may have been added instead of potentially damaging the intake by removing the old pipe plug.

Those are pretty much all the hard numbers I can think of I'll upload some pictures as well to show the step in the plenum and some of the more interesting points. If any more information is needed let me know and I'll get it for you.

Once I get it cleaned up I'll try to get some flow numbers compared to a stock 2bbl intake to see if it flows better than a stock piece, my guess is it will be a good bit better the plenum are is pretty generous and the carbs mount fairly high, I would almost compare it to a "medium" riser tunnel ram (you might need to be patient for this I'm building, slowly an inexpensive flow bench).

Hi Im mounting an edmonds on my 327 ,I have the carbs and obrian truckers has reissued the aircleaners albeit with a paper element rather than the oil baths
what about the exhaust? I will put a plate over the open gap of the one piece exhauset and snip out the thermal spring controlled flapper I hear dodge iron v8 327 pick up truck exhaust manifolds can be used ,the mechanic says the two duals would be really loud

Visually a small block Chevy or Dodge V8 header could be made to work (never tried it but its looking very inviting). It would take a decent amount of cutting and welding but the ports are close enough to where it could be done. Personally I don't like welding on cast iron so I would go aftermarket steel for mine, but if you are or know a good welder Iron could be made to work. Some shorty "street rod" headers would probably be best

http://www.rjays.com/Exhaust/pert_imgs/ptxH8027-1-lg.jpg

Something like those. You can usually pick up painted steel for around 75 bucks or stainless for 100 off ebay. wouldn't be as powerful as a custom set but a whole lot cheaper, its also much lighter and flows better than what the factory had.

Putting a plate (with a gasket of some sort) over the factory exhaust manifold heat riser would probably be the cheapest option out of anything. I wouldn't thing you would HAVE to cut the thermal spring to make it work just make sure the top is sealed up and it would be fine.

You referenced the sound factor of the dual carbs. You will have some noise over stock more from the lack of silencer on the carb than anything but it will not be too crazy. Honestly if you are not very use to the way the engine sounds completely stock you might not even notice.
I have ran some rather large carbs on the street back in my "racing" days with 800 CFM and no air cleaner you would hear just a little of the air coming into the carb while driving. Normally and under more spirited driving the engine noise drowned it out.