Hello gentlemen,

Background: 56 TBird with 312 YBlock, ported ECZC heads, EZC 9425 intake, mild cam (275/.423"), dual-point Mallory YH distributor with dwell at 31, stock exhaust, timed at 18 BTDC. Has a BG Speed Demon 575 cfm carb that I'm very happy with.

My question: the old Ford book says valve lash for both intake and exhaust should be set at .019". (I'm running regular stock valves). Does that figure still hold? What is your experience.

Thanks very much,

Joe

.019 lash is the generally accepted figure for these motors.  I am sure that some of the guys here can give you more advice for this, but this is the best starting figure.

Jan  Urbanczyk  Major USMC Ret.

                                                                 Bowie Maryland

Joe:

I tried to answer, got detatched from the forum.  I'll try again, hope I don't post the answer twice.

You must set the valve lash to the spec supplied by the cam manufacturer.  The .019 figure is for stock factory camshafts.  Aftermarket cams seldom use .019 clearance.

John

John - "The Hoosier Hurricane"

I  stand corrected.  Listen to the guys like Hoosier Hurricane who really know what they are talking about.

Jan  Urbanczyk  Major USMC Ret.

                                                                 Bowie Maryland

Problem is I didn't build this engine. I think judging by the specs I was given on this camshaft, it might have been a custom grind, but not entirely sure. I looked around to find cams with similar lift and duration and found an ISKY that's less duration (260) but same lift, and that one specifies a .015" lash. Meanwhile John Mummert's website doesn't seem to list the valve lashes for his common cams, but...would I be way off base if I split the difference and figured .017" when hot? (And since I'm not experienced at doing this, perhaps set at .018" cold?)

               Well I think your on the track with those settings, when i used to race dirt tracks we would mess with lash settings either up or down from the specified setting to actually get more bottom end or top end depending on the size of our tracks. But seemed to be if we went over gapped or under gapped by about .003 to .004 we would have issues!!

Todd Watertown S.D.

I have found on my 59 Ford 292 .018 cold is where it seems to run the best.

John F

Ballwin, MO

As John says, non-stock cams will not necessarily use stock valve lash settings.  If you don’t know the specs, then try the 0.019” lash setting and if it sounds excessively noisy, then reduce it to 0.015” and give that a whirl.  If possible, find out who the manufacturer of your camshaft is and get in touch with them for the exact lash recommendation.

Lorena, Texas (South of Waco)

Will I need any special tools to do this job? The Ford manual shows one, but the rest is kind of vague.

Nothing special or at least what I’d call special.  Feeler gauge set and wrenches that will remove valve covers and fit the adjusters on the rockers.  If you haven’t done anything like this before, then I’d suggest having someone that has done this before looking over your shoulder while you’re doing it.  It’s important that the lifter be sitting on the base circle of the camshaft and not on the lobe when doing the adjusting.  Here’s a link that may help.

 

Adjusting valves

Lorena, Texas (South of Waco)