Lotus Elan and Lotus Elan Plus 2 Forums

No action in the 'Common...' section so I'll repost over here.

I'm trying to track down a ticking noise and as part of the 'journey', I noticed the valve clearances are quite wide: Intakes are .010 and exhaust are .014 to .015. The cams are reground with specs of, intake: .417 lift, .105 ATDC lobe center, 247.4 duration. Exhaust: .416 lift, 105 BTDC lobe center, 247.7 duration. Valve overlap of 37.6 crank degrees. This all from the cam spec sheet.

I asked the engine builder if I can close up the clearances and he said those are in spec per the cam grinder, but he couldn't tell me the consequences if I closed them a somewhat, especially the exhaust. Actually the exhaust clearance calls for .012-.014, still a bit wide for my tastes, in regards to tracking down the ticking noise.

So, the question: Can anyone tell me what the consequences might be, if any, if I close up the specs to something like .008 on the intake and maybe .009 - .010 on the exhaust, based on the cam grind?

As an aside: the shims in it now are really big, using the top hat style on the exhaust side and I did purchase some shims to cut the clearance to .012 but I had to take off about 2mm of the skirt of the shim to not hit the keepers, which tells me there's not a lot of tip left. Maybe one of the shims could be 'rocking', causing the ticking?
Just another thought.

Thanks!

If you mixed up the cam followers or you may have one thats loose in its bore -it is very important not to mix the cam followers up and return them to the bore holes they came from ===ticking lifters are not bad if you hear the valves you wont have to see them -[old axiom ]--ed

Thanks Ed. Cams haven't been out since the build, about 5k ago. Ticking has been there from nearly the beginning.