|
By joey - 17 Years Ago
|
|
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
|
|
By Cactus - 17 Years Ago
|
|
.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.
|
|
By Hoosier Hurricane - 17 Years Ago
|
|
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
|
|
By Cactus - 17 Years Ago
|
|
I stand corrected. Listen to the guys like Hoosier Hurricane who really know what they are talking about.
|
|
By joey - 17 Years Ago
|
|
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?)
|
|
By tnt56 - 17 Years Ago
|
|
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!!
|
|
By John F - 17 Years Ago
|
|
I have found on my 59 Ford 292 .018 cold is where it seems to run the best.
|
|
By Ted - 17 Years Ago
|
|
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.
|
|
By joey - 17 Years Ago
|
|
Will I need any special tools to do this job? The Ford manual shows one, but the rest is kind of vague.
|
|
By Ted - 17 Years Ago
|
|
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
|
|
By DANIEL TINDER - 17 Years Ago
|
Joe,
Since you did not build this motor, likely you don't know how much wear on the rockers?
Unless they are fresh, and you have an educated touch with the feeler gauge, accurate lash settings a crapshoot.
If you really want to set them close with the least fuss (assuming you figure out what they SHOULD be), and want to get into doing your own mechanical adjustments/maintenance on a regular basis, I recommend picking up a vintage P&G gapper tool (I like the 300 model). A couple .000s either way can really make a difference in how well a Y-block runs (see: HRM June/'61).
|
|
By joey - 17 Years Ago
|
|
Ted (1/21/2008)
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.DANIEL TINDER (1/21/2008)
Joe,
Since you did not build this motor, likely you don't know how much wear on the rockers?
Unless they are fresh, and you have an educated touch with the feeler gauge, accurate lash settings a crapshoot.
If you really want to set them close with the least fuss (assuming you figure out what they SHOULD be), and want to get into doing your own mechanical adjustments/maintenance on a regular basis, I recommend picking up a vintage P&G gapper tool (I like the 300 model). A couple .000s either way can really make a difference in how well a Y-block runs (see: HRM June/'61).Thank you for your replies, and for your reference links. I will read all the material. The reason I asked about special tools is because the Ford manual describes a "Combination Adjusting Tool" to be used for valve lash adjustment. I can't see anything I couldn't accomplish with regular tools but I wanted to make sure. Daniel, I looked up that P&G gapper and it looks like something I should have. 
I'm going to scout around to see if I can find one used before I start this job. To answer your question the rockers (entire valve train) was new exactly 10,200 miles ago, so they are relatively fresh. However, valve lash is something I still want to check on. Joe
|
|
By DANIEL TINDER - 17 Years Ago
|
Joey,
Just make sure it has the "X" base adapter (for OEM Ford/Y-block retainers) and "#2" inner barrel. The cable/camera dial-lock switch not really needed (unless you have a truck cam and can idle with a couple of plug wires off) as dial is just too hard to read accurately with motor running. The "J" rocker hook comes in handy though.
"Combination adjusting tool" mentioned in the manual for early jamb-nut adjusters?
|