Twin H VS Clifford single four

esfoder

Any thoughts on which intake makes more power on an average street machine?





I know the twin weighs about 200% more and I'm not real concerned with the origional look on this car..

[Deleted User]

According to conversations with the late Jack Clifford, the intake and exhaust manifolds are the biggest power robbers of the Hudson six, I have a 308 bored to a 326ci and I'm currently using a 7x cam from Clifford, with the stock twin H and stock exhaust and the car feels like it is trying to poop a grapefruit every time I get on it, I have the Clifford split headers to put on this winter and was just looking at the intake manifold as well.

Unknown

zombiescustoms wrote:

According to conversations with the late Jack Clifford, the intake and exhaust manifolds are the biggest power robbers of the Hudson six, I have a 308 bored to a 326ci and I'm currently using a 7x cam from Clifford, with the stock twin H and stock exhaust and the car feels like it is trying to poop a grapefruit every time I get on it, I have the Clifford split headers to put on this winter and was just looking at the intake manifold as well.

The late Smokey Yurnik used to tell a story about how he made Hudson twin H manifolds smooth on the inside... he devised a sand slurry pumping machine which he adapted to Hudson intake and exhaust manifolds. By pumping the sand slurry through the manifolds he got them thin and smoothed the inside which improved the flow of both manifolds. He gave HP improvement comments which I do not remember.

Unknown

they still do this, it is actually called extrude honing, and when I was into modifying Dodge neons, geez..... this was a common and popular practice to do with the aluminum intakes. I bet if you look around you can find someone that offers this service.

[Deleted User]

No doubt a dual or triple intake is the best, with the triple Weber being the ultimate when properly tuned. The more even the distribution, the better. The layout of a Twin-H is as near perfect as can be short of the triple weber, except the weight and my desire that it be a dual 2 barrel. The Twin-H is a good intake for street use.



Next on the scale, is the single four barrel. However, if you keep your spark plugs checked - you'll always see a little difference in the colors. Lean on 1&6, Just right on 2&5, and rich on 3&4. The big advantage with the single four barrel is no carb synchronization and better breathing than the stock two barrel. Carb choice is a booger, you need to consider how many cfm a Hudson pulls. A liberal guesstimate is 320-340 cfm @ 5000 rpm.



Even a 390 Holley is too big, but close. Its vacuum secondaries keep the velocity up in the secondaries well enough for the boosters to function good. A mechanical secondary @ 390 cfm won't do as well.



Since we've been going to car shows, I've run into alot of old dirt trackers who ran the Hudson. The original Twin-H or a Clifford 4-barrel intake with the right sized 2 barrel adapted to it come up most often as the setup of choice.



Mark

esfoder

Well I agree that 3 carbs spaced evenly is the best setup. The love of my life is giving me a lincoln tig welder for x-mas this year(yes I'm a lucky man) so I figure I'll build me one. I have three wa-1s and might as well make one for those. Any ideas as to what cfm the wa1 is rated at? Another thought is to put a two barrel in the middle and the two singles on the out side with a progressive linkage.(Common plenum)



I'll keep you posted on the progress Or lack of!!





Any ideas would be great???

[Deleted User]

If you intend to fabricate, I'd go with 3 ICH weber 1 barrels. They are about 130 cfm each, which puts you in the money cfm-wise for the street.



Not too pricey either, but I haven't checked lately.

esfoder

Hey hudsonator would you use the webers for tuneability reasons?

How about the Demon 98's. They are pricy but might work really well in a two carb configeration?





Dusty

Kdancy

esfoder- if you are still on the forum, did you ever build the three carb setup?

Ol racer

FYI

Thru the Yrs ive fabricated a lot of Intakes. Three Webers are the very best SetUp but ive never had them. Three single Hudson Carbs would be nice for the street in a slightly modified motor, but its hard to improve performance over the stock Twin H with its equal runners. Usually a smaller carb set-up is quicker (much more responsive) than a large or multiple carbs. Multiples are only good for all out racing.
My favorite set-up is a Twin H manifold adapted to dual 2bbl Carbs from a Chevy or Dodge V8. I milled down the 1bbl bases, die ground out the bores, then bolted down 2bbl adapters and utilized the Twin H linkage. Idles nice and runs Great...

Regarding Headers.... Install a Set really helps performance as mentioned, but recommend 'Coating' so they dont rust out over time....

464Saloon

Hey Mark, How the heck have you been. Haven't heard from you in a long time. You might remember my motor let go back in 07 and I set out to build a heavily modified motor. Well it got done and ran pretty well for about two years or so but I could never figure out why it would lay down about 3800. With the cam, porting, headers it should have pulled to 5000 easy. I had Randy Maas do the Weber venturi enlargement on my Twin H. Had a few problems with that at first but got them settled down. Still didn't help the top end. So I took it to my buddies at Superior Automotive Engineering in Anaheim Ca to run on the chassis dyno and sure enough it was dropping power at 3800. The conclusion was weak valve springs which puzzled me as I think I got those from Randy with his cam. Anyway the car needed a lot of other work and the motor had some oil leaks I wasn't happy with so I pulled it. After getting the head off it turned out I had some cracks. I think that was cause from a Hudson meet trip where I had the timing too far advanced. Lack of knowledge how to time the Hudson properly. They are weird compared to the motors I am typically used to. Upon further tear down the guides were shot which started to point at the machinist who also set up the springs. I was never really happy with his work anyway so I have been working with Superior to straighten everything out. Very sharp place and the owner is in his late 70's so he has a soft spot for this project. So it has been sleeved, pinned, replaced springs and guides basically gone through again. We have modified a Clifford head, welding the chambers into a heart shape and giving us about 9.2 compression. I am taking the twin h manifold out there as he is wanting to make a custom manifold for it. Told you he has a soft spot for this thing. When all is done we are going to put it on their engine dyno. I am hoping to make a local chapter meet out of it and video the whole thing. Should be fun and hopefully informational for everyone. Rob

50C8DAN

This is a company that specializes in in honing with abrasive slurry:

http://extrudehoneafm.com

http://en.wikipedia.org/wiki/Extrude_Hone_Corporation

LHudson

Hey Rob. I am Marks father. He don't get on here much anymore. He is out fighting the Civil War. Has been into that the last few years. He has not gotten his stroker motor together. I have been running the 49 a lot the last few years. One of his last projects, was tuning the carb. on the 49. We are running a Clifford intake and headers. The carb. is a early AFB, about 390cfm. We installed O2 sensors in the headers. He tuned it to run at about 3500to4000. It took some doing but it will get up and go very well. I will atest to that fact. We never installed the Weber set up. We have never ran the Twin H set up. If it does better than the set up we have it is something else. One thing we discovered was the carb leans out a lot above 3000. Mark mixed and matched a lot of different parts from AFB and Edlebrock carbs. Carberation and timing are the keys to letting the engines run like they were suppose to. I will let Mark know you asked about him. L Hud

464Saloon

L Hudson. Oh I just realized when he posted, I didn't see that this was such an old thread brought back up. I used to have his email and we would chat a lot. I last remember he was having financial/business issues and then he kind of faded away. I hope he is doing better I do miss our chats

LHudson

He is well and fine. He worked his way through all of his financial problems. He has little time for sidelines. Between his work and his farming he has little time. He is a grandfather now. He gets to go to some shows with me on occasions but not often. Only one show this year. I am keeping the 49 warm so it will be ready when he gets the urge again. lol L Hud

464Saloon

Good to hear. Tell him I said Hi and to drop me a line so I can send him some pictures. It will be a new car basically when I am done.

Kdancy

464Saloon, did you get Hudson engine finished up?