Projects Project: 331 Hemi in 1950 Hudson Coupe

Well, I thought I'd start this thread as this is going to be a fairly long process and I want to do it right. Thru some bit of fortune, I have picked up a 1955 Chrysler C300 331 Hemi, or at least the important stuff. I am missing some things like valve covers (I need the dimpled ones), crank, complete rods (mine are missing the caps), oil pan, cam; but these can purchased. My plans are to install this with an automatic tranny in my 1950 Hudson Coupe which is also a long project in and of itself. Since I'm also trying to finish my son's '56 Dodge 2dr HT, I will be buying parts as I can, trying to find the good deals with the help of guys here. The block is clean with cosmoline, the cylinders have the cross hatched marks and it's been line-bored, the heads look to have been done, along with the adjustable rockers. Of course all these will be sent out soon to double checked and miced. I hope to pick your brains guys and can't wait to get this baby fired up!

 

The first step, that doesn't cost anything, is to start the planning. I want to have a nice street/strip (once in a while just for fun). I need to be able to run on pump gas (which in AZ is 87-91 w/ seasonal oxygenation). Since I can't afford to go the blower route (man, that is so sad too), I will run with the original dual quad manifold, probably with a couple adapters and Edelbrocks run on progressive linkage.

So, any thoughts on c/r, pistons, rods, cam, etc. you guys have please let me know. I'm also reading all the Hemi technical sub-forums. Suggestions for the planning stage are appreciated.

This is my first "planned" engine build so I may have what some would consider "stupid" questions, so please be patient.

 

Awesome starting point, you came to the right place, much great info here. Just do a search on hemi or hemi tech and prepare to do a few hours or days of reading!

 

I guess we'll ignore the other posts and start over?

10:1 is safe on pump gas, but the only way to get there is with forgings. Use a 56 style cam. Use your cam retainer plate if you have one, you will also need the 56-58 style beveled washer/spacer and woodruff key.
With a bit of work you can install a 392 crank (if you can find one) or stay with the stock unit...but then you can also weld it up and offset grind for a few more inches. Stock rods are fine with a stock crank, or go to Eagle or ?? for rods for stroker pieces. 383-400 rods work well with the 392 crank swap.

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Hudson steering is going to give you some clearance issues for that swap, I suspect, based on looking under the hood of my own '49.

As for the Hemi, I'd be shocked if there wasn't a crapload of tech threads you could research using the search feature.

 

Sounds like an awesome project. I'm going to be really interested in how you handle the steering problem since I'm stuffing a 331 into my 1950 Dodge. Make sure you take lots of pics of that part!

 

Glad you started this Jay! Now we can focus on your questions at hand!

I know you had a lot of questions regarding what you REALLY need to do with this motor for the performance you're expecting. Maybe you should re-state some of those questions, but I saw you mention everything from push-rods to Pontiac rods in those threads.

Stock replacement 331/354 rods will be just fine! Pick up a set of some used rods in good shape and drop them off with your machinist to have them inspected and cleaned up. Could even have them peened if you wanted. Probably not needed.

Something to think about, since you need a starter and flywheel is, make sure you get a matching set. (I.E. 172 Tooth arrangement or 146 Tooth arrangement) The starters cannot be mis-matched. So check out your adapter options in the Transmission Adapter threads in the tech section and you will find out what you need for an adapter and what starter is recommended. You may have to go with a right-side starter (passenger starter) if you're going to have steering clearance issues.

Planning is always good! Just ask away and we'll be glad to get down on your questions and help you figure out what you need.

Again, re-state some of those questions. Can't remember them all.

That intake is AWESOME!

 

Pic of car?

 

Yeah! I second that! I would like to see the car because Hudson's RULE, but also because I'm curious about the steering issues mentioned.

Hudsons are sort of light, if I recall. Might not take much to get that thing going. Unibody, right??

 

Bruce Crower of Crower Cams put a Chrysler hemi in an bathtub Hudson coupe in the early '50s, blown with carbs for Bonneville...understand that yours is for the street, but still a cool precedent ... think he ran over 150 on gas with it.

 

Attached are pics of the Hudson as I originally bought it and had it shipped out here (it's black and white) but after tearing down the fenders, the dreaded perimeter frame rot was there. So after searching for a couple years, I found another '50 Pacemaker Coupe in Maricopa, AZ. I bought the car with another guy who wanted the other parts and I kept the unibody, front fenders and rear wheel wells, and rad support side panels. I plan to install the frame stub and MII kit strip the shell and use the useable parts from the original car on the unibody.....one out of two!

Sorry guys, I should have mentioned the Hudson is getting a Fatman's stub and MII kit w/ power rack and pinion. This should give lots of open room for things.

 

Sorry, scooter suggested this one thread, so I'll keep everything here from now on. At least it's in one place.

 

From the look of those rockers, I'd for SURE break them down and sanitize them inside and out...especially inside. To keep everything where it should be, letter/number stamp EVERYthing...ie stamp each rocker for the position it is on the engine...I2/E2, I4/E4, etc, then an indicator of some sort for which shaft is the intake and which is the exhaust and which end is forward. Also just as important, the position of each individual rocker stand...D1, D2, P1, P2, etc...D=Driver side, P=Passenger side. If you screw up the rocker stands, you'll sure as hell put the oil feed stand in the wrong position and starve the rockers of oil. METAL STAMP your reference marks...that way whatever solvent you use won't wash off the reference marks. Each rocker has oil feed holes. Use the correct size drill bits and twist it back and forth through the holes BY HAND to get the baked on deposits out of the holes. Do the same to the feed holes in the shaft and oil feed rocker stands. The holes through the center of the shafts themselves need to have the 5/8" welch plugs removed and the holes cleaned out...they will be almost, if not, plugged solid with sludge. Use a digital camera, when you can...they're a great help in reassembly. When you reassemble the rockers/shafts, use a thin coat of a light grease. They'll rust/seize quick if you don't.
If you are going to use a Chevy automatic, get the adapter for it that puts the starter on the passenger side...it will use the Chevy flexplate and starter. I used a mini starter on mine...

 

Thanks for the hints 345 Desoto. I learned on my Dodge, it's a torn down to just the bodyshell sitting on the frame. I bouht tons of "zip-loc freezer storage bags that I write on with a sharpie. I draw pics and store in a file to know how something goes back together. I'm almost anal about it. That's why there shouldn't be any, or at least minimal, problems putting that car back together. The rockers are very clean on the outside though it may not look like it in the pics. I am going to do as you suggest and tear them down. Good idea about the drill bits to clean out the holes, I'd forgotten that one. When I bought the Dodge I bought a small set of number die stamps to use as needed. I also use yardsticks driled and marked with a sharpie for hanging valves and such. I have learned to use some, sometimes wierd, methods for marking.

As a side note, I have advanced atrophy in the brain and other neurological issues that have a really bad effect on short-term memory. Because of this, I am very aware that I must be vigilant in doings things in a way that will assist in keeping everything as it should be once they need to go back together. Just a bad hand of cards, but I have learned how to deal with it. That's why all suggestions are especially appreciated.

Keep mthem coming guys and I'll try and post my questons from the other threads here later today. I'm off to volunteer in my son's classroom this morning.

Jay

 

Please, for the safety of yourself and of the other unsuspecting motorists out there, reconsider the dreaded "stub/MII/power rack"syndrome. This stuff is fine for a lightweight 6 cylinder or lightweight small block powered whatever, but not even marginally capable of safely handling the weight of an early hemi, its related cooling system, modern tire technology, and the overall weight of the car. Looks to me like the frame in the pictures is straight and certainly could be strengthened and improved on with gussets and braces to handle the load an iron hemi is going to impose. Said another way, how much did the original Mustang II weigh, what type/size tires was on it, and what was the front to rear weight distribution.......

 

Congratulations on picking a great nostalgic hot rod Hemi engine for your Hudson coupe project.
As soon as I read about your thread, it immediately brought to mind the one Bruce Crower ( as also mentioned previously in this thread by 296ardon) ran 150+ MPH at Bonneville. As a young man in the late 50's or early 60's, I was lucky enough to personally see this car (This was after his World Record Bonneville runs) and watch it make several 1/4 mile passes at a local drag-strip just outside of Phoenix, AZ. It was not setup for drag-racing and spun the tires almost the whole 1/4 mile, but it did make some very impressive horsepower. If my memory serves me, I think he had a 6-71 GMC Supercharger with 8-2's on top of that Hemi, and the stock hood still closed and latched. From what I remember,I think he drove the car to and from Bonneville, after his record runs. To say the least, it was a very big deal for me to see and, watch it run.
During this same time frame, a friend and I also built a car (51 Ford cpe.) with a 331" Hemi that I raced in and around Phoenix, but thats another story.
Good Luck, and I'll be following this thread for future updates.

 

I have looked at different articles and talked with Fatman's tech guys and these stubs have been used for particularly any kind of set-up. They use different springs depending on your motor application. They used a stub on a Ford pick-up with a 392 Hemi. So, I'm not worried at all about using this stub with the 331. The front suspension on a Hudson was good for it's time, but the center steering bushings are a major pain, having to be changed out all the time unless you happen to have a perfect link which is difficult after so many years gone by. Engineering wise, I don't think 50 some year old technology is always better than what they can design nowadays. These stubs and all the MII systems out there whether Fatman's, TCI, or others, have all been engineered for hot rods and customs being built today, they are not using the original Mustang II specs. The MII is just the common name used for these systems since that's where the design originally started from, The systems out today, are certainly not engineered exactly like the old Mustang II's. They were a bit scary back when these were being robbed out of the Mustang II's and adapted to hot rods. I used a '63 Corvair van IFS and heavier springs when I built a '38 Dodge coupe with a 327ci back in 1980, I just didn't like the weak appearance of the original MII's.

So, don't worry, the stub will be just fine and I don't anticipate having the front end come flying off at 80 mph on the freeway! (though that might be one hell of a ride....probably to one's death though! :-().

 

Thanks RHestand, wish I could have been there to see that! But I was just coming into the world than, actually in Phx (but shortly our family moved back to SoCal). The supercharger is a dream, but I don't think I can afford one unless I hit the lottery out here, or by some small chance someone feels charitable and will take a lower price (I'm dreaming again I know! lol). But I think I may be able to get some decent speed with the dual quads running on the original manifold and the help of planning by folks around here.

 

Yeah scooter, the Hudsons have a real nice set of lines on them, though I was actually looking for a Merc when I found out about Hudsons. I knew nothing of them, but have grown to love the design of some of them. I am now an officer of the AZ chapter and have great fun with the members. The Coupes have a nice look to the top and trunk, though the Broughams (2dr sedan) makes the best slope for a chop. There is one sweet chopped Brougham over on another forum I post at and it's the best chop I've seen on one. The coupe tends to have a gun-turrat (sp?) top, which is why they look best unchopped IMO.

The steering is a major pain when putting in anything other than a flat six. The center-point steering is in the way. There is a guy up in the NW that has put a 396 BBC in the original frame, though had to make a few mods to the firewall engine stance in order to make it work. It can be done, but personally I don't like the center point steering on these. They have a bushing that's always going out and it's really hard to find a good shaft that allows the bushing not to wear so quickly. But that's just me. Others like it just fine. Yeah, they are light, I think mine weighted in around 3,200 stock, a lot less than many sedans today. The unibody gives you a nice low center of gravity, though sometimes that perimater frame is a PITA, especially when it comes to a c-notch, though I've seen it done.

296ardun, another one that I would have liked to see.....ahh, if only cash was not an object! LOL

 

Same motor I have in my 51 Merc.You might try G&G Mopars for your valve covers (909)825-0307.

 

So I'm going to try and move the questions I previously had around the various Hemi Tech threads to here in one place. I have read a lot on the Tech archives, so if I post questions here, it's because I still want other's opiion and suggestions or that I didn't fully understand something. Some of you may think questions are idiotic, but I'd rather be considered an idiot than build the wrong motor and prove it.

One of the first things I read about is the piston/rod/mains/crank issues. I do not have a crank, pistons (well there melted), rod caps (and I don't think I want to trust the rods either). I know 73RR has stated that I could go with a 392 crank which I believe it will need some machining on the mains, crank, and the rods in order to do this. How difficult is it to get a 392 crank?

Will it be easier to find and use a 354 crank. I see some cranks advertised on eBay (many with a 20/20 grind noted) and very rarely ones on Craiglist. I understand that even a not so good crank can be purchased and machined to good specs?

Is it easier to find a 331 crank? Since I have a '55 C30 block, is there anything specific I need to insist on like certain years, none ground over a certain spec, etc.?

I need this to be part of an overall plan, so if you guys could give me some additional needs/wants while using a 392/354/331 crank, it would be useful. Like, say you recommend a 392 crank, would I then need to figure on using Pontiac rods and have them machined, would a specific piston size be recommended along with it? Etc. This way I can plan on what to be looking for when shopping around. Time is not a major concerned because I have to finish another car and the Hudson will be a long term project.

I will post the other questions to date here soon.

 

Thanks for the tip, I'll give them a call today or tomorrow. I also have a line on a guy my neighbor knows that has tons of Chrysler hemi stuff from all years, more than he even knows he has! Im going to try and make a connection there as well. I have a feeling those are going to be an expensive deal, but they look cool! Nice set-up you have!

 

The 331 and the Hudson should make for a beautiful and potent combo. The hamb is a great source for info and parts for your hemi build. I have managed to save quite a bit of money by watching the classifieds and not being in too much of a hurry with my own hemi build.

 

Well, Jay, not to worry about engine related assembly. Plenty of help on the Hamb when you need it...as for short term memory, many of us have that problem without a diagnosis...

As for valve covers, you have several choices and prices generally reflect condition.
Check this link: http://www.jalopyjournal.com/forum/showthread.php?t=112948&highlight=hemi+valve+covers
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Been reading and listening on cranks, pistons, and rods, so how about I throw this out for the group to consider. It seems 392 cranks are very expensive, require lots of machining mods, and are hard to find, so I think I will rule it out for now.

My thought was what about using a 354 crank w/ 1/2" welded stroker, Pontiac rods, and not sure on the pistons, maybe stock hemi pistons? In reading it looks like the Pontiac rods will give you cheaper rods and bearings, and the 1/2" stroker crank servicing gives you a longer stroke. Is it worth the machining cost (flatlanders price is $725) to get the extra 1/2 inch stroke? Maybe it's not, what do you think? I have no rods now and no crank, so whatever I do, I start from scratch. 392 cranks, I think, are just out of my price range and that extra money could be used elsewhere in the build.

Since we're on cranks, is a 50+ old damper worth using? Or is it better to buy a later model LA damper and one of Tom Water's "stepped crank keys" so you can buy a stock one and not have to buy a "modified" 340 damper, like the one Hot Heads sells?

I'm starting at the bottom end guys, what are your thoughts?

 

Comments in RED...

 

Jay, don't over-think this. These are not small block Chevy motors. You do not need crazy high lift cams and other wild stuff to build a good performing and a reliable Hemi. These are remarkable engines!

What kind of ACTUAL performance numbers are you really looking for??

 

Any 55-56 crank from a 331/354 hemi or 301/331/354 Poly will work.

 

An reason you didn't include 1951-1954 years, George? It's Leo's book again, isn't it!?

 

Scott, just how short is your memory..??? Remember that little 0.200" problem recently discussed ?? You, my friend, are waaaay too young for CRS.

Cranks from 54 to 58, 301-331-354 will all work.

...I am almost sorry that I mentioned stroking as an option....
Jay, give up the Poncho thing. As Scooter suggests, the cost to make them work will be more than paying the premium for the 354 bearings. If you really want to add some stroke for bragging rights then match the 392 stroke and use the 383-400 rod. This will raise the pin 0.014" but still allow you to use a stock replacement piston. The 400 rod bearing is cheap. However, if you want more than 8.5:1 comp then make a slightly longer stroke to move the piston higher or use all stock parts and buy a set of forged pistons. The $725 number you have for crank work is about the same as a set of 10:1 forgings.

Unless your stock dampener is in excellent condition, replace it. ANY late small block dampener can be fitted by either re-broaching the keyway or by using a stepped key. Anyone with a mill can step some key stock. If you re-broach the hub then just remark the outer ring for timing marks. Virtually anything you do to install a late dampener will require new markings. Timing tape also works well. This is not rocket science.
FWIW, we also sell all of the aforementioned stuff......


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