Does anyone know why TA says to set valve lash on their solid cams with the engine cold ? Seems to me it should be set when the engine is warm . The engine doesn't run cold after all...My cam is quiet when its cold but the valves get noisy when it warms up..What are you guys doing about this? ....
Mike, You have aluminum heads, right? I have the same issue with my heads. Valves are dead quiet when cold, but get clickey when hot. I e-mailed JW about this. Apparently, the aluminum heads grow quite a bit when hot, and the lash increases enough to cause some noise. Here is JW's reply to my question on whether aluminum heads require more lifter preload. "Larry, more preload.. as an example, when I set lash on a solid lifter cam motor, if I want say .022 hot, I will set it at about .012 cold on the stand, and it will about right when we re-check them hot on the dyno. This is with alum heads. They swell up that much. I typically set alum head motors on the stand, with roller rockers and a hydraulic cam, at 3/4 of a turn past zero lash. Under steel covers, roller rockers will be just a touch noisey, but not objectionable typically. Nothing you can hear without the hood open typically. But all this can vary, Alan's motor was silent when I ran it here on the stand, and on the dyno, and you have heard that one now.. Rocker noise is a pain in the ass. All of my vendors that do machine work for me, also build engines, and not one of them will guarantee perfectly quiet valvetrains anymore. JW"
Larry i do have stage one aluminum heads, the cam card calls for .022 on the intake and .028 on the exhaust cold .I didn't realize the heads swell that much :shock: I guess the valve covers are coming off again time to tighten this bad boy up some ..So whats up with the cruises here on the island anybody doing captree yet? Thanks for the help... :3gears:
I plan to tighten my lash 1/4 turn, and see if that makes a difference. Captree never stops. As long as the roads are clear, and the sun is out, there are cars there every Sunday. Ron and I have been out there a few times during the fall and winter. After Memorial Day, the Captree lots starts charging $$, and the action moves to the old OBI lot(mob scene). But I think this year, they will be building there, so who knows. As far as cruises, there is Kohls parking lot on Saturday afternoon/evenings(was there this past Saturday) 4 miles south of Exit 52 LIE. Also Tuesdays on Hempstead Turnpike, just east of Newbridge Road in Levitown. Bellmore should be starting soon.
Something sounds fishy to me. .022-.028 sound to me like hot lash not cold. With Iron block and alum heads we set the lash .005 tighter when cold, and recheck on the dyno after it gets to operating temp. Usually pretty close.
Rick, Are we talking Buick aluminum heads or just aluminum heads in general? Might different aluminum heads expand more or less? Pedestal roller rockers vs. stud mounted rockers. Could any of that make a difference?
On my solid roller I set them cold just for the convience of doing them at home instead of at the track However,I use the same as what Rick mentioned above. Go about .005 tighter than the card calls for and that will be good when hot.
.005" tighter is just a general figure. Their are too many variables to make it a steadfast rule. If you want to set things cold, get the engine to temp and set one cylinder. Then let the engine cool overnight and recheck the lash. Then go ahead and set the rest to the new cold lash setting. You should never deviate from the manufacturers recommended lash setting by more than .004-.005" +/-. The takeup part of the ramp will not tolerate this for a long period of time. If the car runs better ( makes more power either way) then you have the wrong cam.
