EAB valve lash
 

Could someone tell me the valve lash intake/exhaust for this cam I'm putting into 49-53 1ba block with 4" stroke. I hope to have a 276 when finished. I've read enough old threads to be thoroughly confused.

Re: EAB valve lash
 

Not sure this will be of any help but the 49-51 Merc Manual says:
1949 and 1950 valve clearance (cold) .010 " to .012 intake and .014 to .016" exhaust.
1951 Merc valve clearance is shown as .013 " to .015" intake and .017" to .019" exhaust.

Another reference book shows 1953 Ford 239 V-8 is .014 " (cold) for intake and .018 " (cold) for exhaust.

Re: EAB valve lash
 

Seems to be more than a bit of confusion where the later versions also introduced valve rotators. I thought I was above all that until the inspection of the 59A in my '40 revealed an unexpected mix. The cam marked EA is the short nose, two bolt dist. type. The valves are on rotators. All looked great in the engine but after touching up the valve seating, a similar question came up. What should the valve lash be? The numbers for the rotators look pretty large. Always thought the valve lash specs came with the cam. Hate to get it wrong. Good Luck: Fred A

Re: EAB valve lash
 

This may sound completely O/T, but hear me out. I have a '54 Chrysler Hemi in my vintage dirt car. When I needed to rebuild it, i decided to do it right; I ended up with new forged pistons, prepped heads, and an Engle roller tappet cam for starters. The cam was new, but came with no instructions or even a cam card. I called Engle and had a long conversation with one of their techs (who seemed to know what he was talking about). He told me that anything between .010" and .030" would work fine. The difference is how you want the cam to work. Tightening up the lash increases duration, and backing it off decreases it. For racing at least, he said this was one of the final factors in tuning an engine. He sounded credible and all, but not wanting to take any chances, I asked him if he could get me the original manufacturer recommendation. He finally came back to me with .014" on the intakes and .018 on the exhausts. That's what I set them at, and the engine runs fine. I was vintage racing and didn't need that "last little bit". Since mine was a roller cam, maybe this doesn't apply to flat tappets, but he said it did. Just another factor to ponder.

Re: EAB valve lash
 

Someone on here posted a spec sheet on the different cams, I think it was Tilden or something like that. Anyway it contained the recommended valve lash settings if I remember correctly.

I wonder if the two values given from the merc manual post were due to the 1cm and 8cm cam or the different valve types, rotator vs non-rotator. We may never know.

Jonathan

Re: EAB valve lash
 

Someone on here posted a spec sheet on the different cams, I think it was Tilden or something like that. Anyway it contained the recommended valve lash settings if I remember correctly.

I wonder if the two values given from the merc manual post were due to the 1cm and 8cm cam or the different valve types, rotator vs non-rotator. We may never know.

Jonathan

Re: EAB valve lash
 

Re: EAB valve lash
 

Thanks for the chart I'm guessing here, but looks like my EAB cam would be .012/.014.

Re: EAB valve lash
 

Thanks. That is a great tech article.

Re: EAB valve lash
 

The change over to rotator valves in 1951 was what made the clearance change as was previously mentioned. If you are running earlier non-rotator valves with an EAB or 8CM cam or what ever stock grind then use the earlier clearance specs. If using the rotator valve, spring, & keeper assemblies with a stock grind cam then use the later 1951 clearances. Aftermarket cams are not included in this recommendation.

Re: EAB valve lash
 

Valve lash is a function of cam design, not the valve system you use.

Re: EAB valve lash
 

flatjack, Thanks.

Re: EAB valve lash
 

FoMoCo designed it and FoMoCo made the changes. The EAB cam was the replacement cam for 8BA family engines for a long time after 1952. A lot of 51 models still used the earlier cams with the new rotator valves as well. Another thing that changed in that time frame was the delete of the stellite valve seats. They may have been worried that the seats were going to break in a little farther and faster.