1954 HUDSON 308 REBUILD

Browniepetersen

After a bad experience on the road today it looks like I am going to be rebuilding my 308 that is in my 1954 Hudson Hornet Special Coupe.  Last 308 that I did I added 5/8" grade 8 studs, Aluminum pistons with slotted racing rings, flattened the head and block, and opened up the exhaust and intake valves to two inches.  Is there anything else I should be doing?

duncan

I also  releived the valves installed a 31 10 40 cam and a Randy Maas timing chain set  1/2 grade 8 bolts and steel heavy flat washers.145 alliminum head shaved 0.40,  Port and polished the intake and exhaust manifold and ports to the best of my ability.Flattened the oil pump cover. pluged each end of oil gallery with allan wrench 

plugs.  54 Hornet Hollywood I also installed the bigger Hudson valves.    super twin H power   Ray

duncan

I also had the hornet 308 engine bored out to    3  7/8  Ray

RichardD

You should get hardened washers--they are made.

duncan

Sorry that is what I used  Ray

Chris Smith

Brownie, if a performance upgrade is in order, consider new valve guides with those 7x valves, cut the valve reliefs to more than 7x, a Maas timing chain, a Hughes full flow oil conversion, headers, have the rod bushings replaced and hone both ends of the rods, grind and micro polish the crank shaft. a bigger cam , cut Singh grooves in the head. A new oil pump gear. Electronic ignition. This is in addition to all the things you stated. Also find a place that thermal cleans the block, head, and intake. If you go the custom piston route, it would be trick to use gapless rings also, and rig up a pcv system. A wheel barrow full of cash will assist in the rebuild also. Half inch grade eight head bolts or studs with thick teco washers are what you want.   

RL Chilton

You're not alone, Kenny!

Lee ODell

What would be the recommended distributor maximum mechanical advance and advance curve and vacuum advance for 7X engine? How much loss of MPG from Twin H engine to 7X engine.

I lost 4 MPG changing from 2 barrel to Twin H.

What are the Pros and Cons going to 7X engine?

Lee O'Dell

RL Chilton

Lee-

That's an abstract question. It all depends on what you are really talking about.  Firstly, you don't want a true 7X engine for a street-driven car, as it would be completely impractical.  You might want some 7X type of modifications that you could utilize on a street car and that would be very do-able.

Also, "7X" and "gas mileage" don't even belong in the same sentence, so forget about those ideas.  A properly tuned 308 (stock) with Twin-H will get 15-16 mpg on the highway, period.  Any hopped-up modifications are going to get you much less.  

Some other cons:  

1.  Hideously expensive.

2.  Not practical for street-driving.

3.  Re-build rate exponentially faster (which means more expensive)

4.  Known, trusted sources to do modifications could probably be counted on one hand.

5.  Time to do the job properly is probably 3X longer than a stock re-build

6.  Irreversible.

7.  Hideously expensive.

Some Pros:

1.  Brag and/or cool factor.

2.  Blowing the doors off other 60+ year old stock cars

3.  (Give me a minute . . . I'm still thinking . . .)

4.  The sound of a dual exhaust on hopped up flathead six with a lumpy cam is truly something to behold for a flathead lover.  

Some thoughts on cost factor:

I believe when you are talking about a project like hopping up a flathead 6, money should not even be a factor.  You have to do it for the love of the marque, the love of the history of it.  If you are an engine re-builder, then it's even more doable.  OR, if you are independently wealthy, then ignore the whole cost factor (although rich people I know don't do that).  Speaking from a bit of experience, the work we did on the convertible's motor was probably beyond what I should have done, what was practical or smart.  Recently, I got to drive the car for the first time and it made the pain of building that engine worth the effort (but it still wasn't smart).  And no, not the pain of physically building it, because I didn't, other than to design what I wanted, but, rather the pain of paying for it.  SOME of the modifications include:

Milled Head

Decked

Line Bored

Compression matched

Ported, Polished

Balanced Dynamically, statically

Monster Cam

Hardened seats on exh. valves

7X relief on block

NOS Twin-H jetted to handle the better-aspirated engine

Gasket matched

Special Ignition modifications

1/2" head bolts

That's a lot for a 60+ year old street engine.  And this is not a brag, just an education for anyone reading this, but keep in mind, I could have BOUGHT 3 Monster V-8's with 450hp/475lb crate motors for what was put into this engine.  (And no, I'm not rich.  That's the main reason this car took 8-1/2 years to complete).  

Don't be discouraged, though!  Just do your homework and know what you are getting into before you run out of gas 1/2 way through the project.  

Lee ODell

Russell

The main reason I ask the question was so anyone wanting to build a 7X engine would have a good idea what they were getting into. Having been a hot rodder, I was aware this kind of build was for hot rodding and I didn't think 7X would be a good daily driver especially for in town speeds and club cruises. Not personally having any Hudson hot rodding experience I wanted to know and everyone else to know, if the build purpose was to once in a while to go fast but still use it as a daily driver to know the down side, if a built Hudson had poor drivability like any other racing motor at slow city driving and for HET cruising.

Thank you for some real insight beyond bragging rights. I know if I had the $$$'s I would probably do it too. As the old say goes: "once a hot rodder always a hot rodder". However I tend to like getter gas mileage today.

Lee O'Dell

KTRON

Why would a 7X modified engine be impractical for a daily driver???  Is this a seat of the pants response or???

If all your doing is increasing the efficiency of the valve train and giving it a little more fuel, you shouldnt need to rebuild it any more often than a factory engine.....providing you have adequate cooling and are not bumping up the governed speed or compression too much...

Chris

Chris Smith

I doubt that many Hudson owners drive them daily anymore so that in mind, the goal should be smiles not miles per gallon. Have any of you seen Butch Smith's blown stroker Hornet engine on youtube? 

duncan

Is there much difference between a 311040 cam and a 309742 cam.  Ray

Browniepetersen

I now have the engine apart and we determined that we bent the rod that spun the bearing.  Also, since there is a lot of clean up required for the crank we have located another one to take its place.  I will be back at the machine shop in the morning to determine what the bore is going to be and then order parts.  I have been speaking a lot with Dale Cooper the past week so the parts will be soon on their way and I can start the machine work.  I will do a final pass once our parts get here.  It is a lot of fun being  back behind the controls of a machine--even if I question that I know what I am doing.

Since the engine is out, I have pulled the hood and fixed the broken spot half way across the air damn opening.  I will paint the underside of the hood before it goes back on.  Also pulled all the stainless grill and will take it down to the shop for buffing.  Yes, I did detail the inside of the engine bay.  I am not sure how one can have more fun.

Glowplug

Swap the crank with a 262 and build an hot rod Hornet engine

Browniepetersen

Been there, done that:  About 95 time frame I built a 1952 Hudson that I raced on the Bonneville Salt Flats and set a new land speed record.  It was a lot of fun, but with this "Retirement" Hudson I expect to have a nice performing car that will take me cross country a number of times.  The build back then was much the same as the engine that will be in this car.  I like to think of it as a modified 7X car with 225 hp.

Chris Smith

That sure is a handsome car Brownie. Do you know where it is now,and is it painted and lettered the same?

Browniepetersen

It sold a few times and then I lost track.  I sold it to buy my English Hudson.  I seem to have a hard time holding onto cars.  This 54 is my last (famous last words) so it should be around for quite a while.

Chris Smith

Looks like a keeper to me also.

Swede

Hello fellow Hornet admirers. I will be selling a 1954 Hornet 4 door with a Jack Clifford Racing built 7X- 308 engine. You might want to take a look if you are interested in the 7x engines. It has: aluminum head, twin H power, aluminum pistons, 1/2 inch head bolts, Clifford headers, dual exhaust, Isky cam, 7x valves, and bored and stroked.
The car will be listed in the Sept edition of White Triangle News.

The car is in good running condition. Located in Washington state.
You can post here if interested. John

53jetman

Well Fellows, my '54 Hornet Coupe engine has had several modifications including 7x intake and exhaust valves, and a.060" over-bore.  The car has Dual Range Hydra-Matic and a 2.62 rear gear.  On regular trips to the Smokey Mountain Nat'l Park from Lima OH down I-75 I  have been fortunate to get 20 -21 MPG time after time, driving at 65 to 70 mph.  This is  over a time period of five years, having driven the car now 11,000 miles.  Granted, you have to keep it tuned properly, but decent MPG can be achieved.

Glowplug

I agree with mileage, my 54 with twin H and hydramatic. Same on engine .060 over and everything was balanced.

Browniepetersen

Not sure what it is with my luck.  Got the engine apart and started the build.  There were some small cracks in the valve ports but they cleaned up with the larger valves to be installed.  Next it was a bad crank, found one and got it machined and ready for build up.  Then it was the cam. Got a new one on order. And, today it is the exhaust manifold with a big crack.  Oh, well, this is fun--or I would not do it..... ya right!

Glowplug

You are actually lucky to find the problems now

Ol racer

I dont worry about minutr crackd... Perhaps consider a set of headers then build your exh fron there, ...Jet Hot Coated would make then last alot forteved. A Lot of power is lost in restrictive stock exhaust manifold....

Browniepetersen

Have all the parts and will now start the assembly.  Did notice that there was another crack in the manifold.  Welded it up today.  It will not be long now....

Browniepetersen

AT LAST all the parts are inhouse or on the way. It became difficult to find a cam for the car; but today, Randy Maas put one in the mail for me. Among other improvements, (I.e. valves, rings, Maas Timing Chain, Al pistons, .040 over, ect, I have selected a Super Street Cam with 402 lift and 276 duration to finish up the build. Excited to get this car on the street. One or two weeks at the most. Not too sure on the math but with the .040 over this should give me about 320 cid.  Not sure what the hp will be with machining, 7X valves and the street cam?  Randy tells me that there will be no difference with the idle with this cam and a stock cam?  Just more "Thump."  By the by, this is all bolted to an Ike Smith tranny...  My error, the cam is a 372/254.  Just spoke with Randy and he saw my post and gave me a call. 

RL Chilton

Sweet, Brownie!  Probably be in the 250 range on HP, but the torque, man.  Should be off the charts!

54Hollywood

Ray,

In case you didn't find an answer to your question about the differences in the two cams, here is some info I found from my old Clifford notes.

The 309742 (7x flat top) cam has a lift of .355" and a duration of 258 degrees.

The 311040 (Super 7x) cam has a lift of .390" and a duration of 268 degrees.

Hope this helps.

Tim in WI.

duncan

Tim

Thanks for the post.  When I bought our car the engine had a 309742 cam in it. one lobe was wore so I used a 311040 cam.I am wondering if this was a good choice .  Hudsonly  Ray

Kdancy

More camshaft info--
http://openforum.hetclub.org/discussion/166655/306344-camshaft-just-profiled#latest