1955 308 engine questions

I have been told by Cole at Wildrick, that I have a crate 308, stamp number F14837.

I've been looking at 7X camshafts on the form from 2015and 2015 as well at 21st Century Hudson.

Today, I looked at my camshaft, for measurements and cast number.My cam number is309742. Lobe height is 1.557 lobe diameter is 1.199 by digital calipers. I again looked online and the form from 2014 and 2015. By my cam number, I have a factory 7X camshaft with hydraulic lifters. I checked the oil pump drive gear, it appears to be a steel gear. When i rebuild my engine, I plan to install a bronze gear and a true double roller timing chain.

My head that I have for this engine is a 308. Larry at Clifford Performance told me how to check for thickness on my head. My head is just shy of 2 inches thick. Larry told my that my head is completely stock thickness. He suggested that I shave my head .060 for better compression

I've built engines as a professional mechanic for 23 years before I retired from the trade 15 years ago. Everything that I've seen of this engine, says that it was a low mileage engine before it was parked. I purchased this engine from Ron Falk. I tore the engine down, including removing the crank, to forcefully remove the rust frozen engines. This destroyed the pistons but no damage to the rods. There are no cracks anywhere on the block, including between the valve seats.

My question is simple, should I use the 2 inch intake valves and 1.687 exhaust valves? If I use these larger valves, will I also need to enlarge the  air intake chambers for better air flow? I know the valve seats will need to be enlarged for the larger valves. At this time my engine has 1.847 intake valves and 1.570 exhaust valves. Years of rust have eaten these valve stems up badly. This includes the valve guides.

Any and all input will be helpful will be greatly appreciated, being that this is my first Flathead engine to work on.

Thanks Wookie



  • 7XPacemaker7XPacemaker Posts: 496Senior Contributor
    edited October 2020
    I am not a big fan of the hydraulic lifters in the Hornet engines. I would go with solids if I had it apart, but that is just my opinion! 
  • 54coupe54coupe Posts: 792Member
    I would only mill the head enough to be sure it is flat and true. My opinion on the valves is that to get the full benefit of going with larger valves, you must open up the block between the valves and the cylinders. I do this on any engine I build for my own use.
  • blondwookieblondwookie Posts: 239Member

    would i have to have my cam resurfaced for mechanical adjustable lifters?
  • blondwookieblondwookie Posts: 239Member

    would you be able to show me exactly how to open up the combustion chambers including porting?

  • 54coupe54coupe Posts: 792Member
    Is your email address correct in your profile? I will see if I can get some photos together to send to you.
  • blondwookieblondwookie Posts: 239Member
    Ya it is.

  • 7XPacemaker7XPacemaker Posts: 496Senior Contributor
    They used to Parkerize the cam to harden it up for solid lifters.
  • Hudnut54Hudnut54 Posts: 3Member
    I would look for a 262 head to get higher compression instead of using a good stock compression 308 head 
  • KdancyKdancy Posts: 2,499Senior Contributor
    Agree with hudnut. Get a good "inspec" 262 head if you are determined to raise compression.
    The Hudson out of spec head thickness is 1.94". I have personally never measured a 308 that measured a full 2", and that includes a 308 NOS head. It miked out at 1.985.

  • pedro31168pedro31168 Posts: 9Member
    sorry to butt in but reading your comments , which are great info. 
    i have a 51 hudson six  with a 308 head can anyone tell me the torque settings please.
    thanks in advance 
  • KdancyKdancy Posts: 2,499Senior Contributor
    Look at the Hudson club store, they have all the manuals you will need to work on your Hudson. Also, Ken Cates hudson website has a lot of extra info. Well worth visiting. 

  • blondwookieblondwookie Posts: 239Member
    Hello everyone,

    I have learned a lot from everyone on this site. I have been looking for cam information on line. I found a rather good cam article written by Kdancy. This article from, I think from, 2014 helped me a great deal.

    I have looked a the information on this site concerning multiple carburetors on a Hudson 308 engine. I like the vintage speed intake tri-power.

    My engine will be turned into a 7X engine for my coupe. I have spoken with Larry at Clifford Performance. He told me that Jack tried the multiple carburetors, with no real success. He found that the Weber carburetor worked the best over any other carburetor.

    I  like to read what everyone says about different kinds of intake setups for my 308. I'm not to sure about using a computer with fuel injection, yet I'll continue thinking about it.
    I have saved many of the documents that I have found as well sent or suggested to me. this includes how Jack Clifford used to adjust his valves.

    When I have extra money again, I'll buy pistons, 7X intake and exhaust valves, along with guides. I have found a race engine building machinist in Douglass Wyoming. He has a lot of experience in machining flat head engines, for performance.

    I'm still slowly dismantling my 48 super six coupe so I can start the restoration of my car. Any more information on my car will help me a lot. I still need a few non wear brackets, like body bumper mounting brackets, being that one of mine had been either cut or torn apart. I also need the rear frame mount bracket for my rear-end sway-bar brace.

    Thanks Wookie
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