TR2/3/3A Finding valve lash with cam specs?

[karls59tr]

Is anyone familiar enough with camshaft terminology that could tell me the appropriate valve gap for this cam: 227 degrees @ .050".........280 degrees cam lift ........ 420" valve lift on 109 degree lobe c/l
Any help most appreciated Karl

 

[CJD]

I'm afraid the specs do not tell the valve lash. You will have to contact the manufacturer for the recommended valve lash. There is a very mild slope on cams that takes up the lash without shocking the valve train...called the ramp. The ramp is something the manufacturer chooses and is not related to the left or duration specs.

 

[Andy Blackley]

Karl:

John's advice is best. Your cam doesn't seem to be on this list: > Triumph Cams <

Valve lash values are all over the place on that list, so its hard to deduce anything from just the specs you have given. Only the cam grinder will know for sure. I note that none of those listed have as much (gross?) valve lift as you indicate.

Andy

 

[karls59tr]

Karl:

John's advice is best. Your cam doesn't seem to be on this list: > Triumph Cams <

Valve lash values are all over the place on that list, so its hard to deduce anything from just the specs you have given. Only the cam grinder will know for sure. I note that none of those listed have as much (gross?) valve lift as you indicate.

Andy

I'm going to get in touch with the cam grinder. I vaguely remember .016 but that seems a long way from the stock .010. The Tr3 seems to run OK at .010 except for an irregular idle. No other modifications except for exhaust header.

 

[Andy Blackley]

I have the Isky TR-555 grind and use 0.015 which was recommended with the documentation.
Seems to work well.

 

[CJD]

The sound of the engine is always a good check. At the proper lash, only we gear heads can hear the slight ticking from the valve train. If there is too much, then it starts to sound like a sewing machine that your wife thinks is "cute"...the point being everyone notices the excessive ticking. If too tight you hear nothing, and normally get a rough idle.

 

[karls59tr]

I have the Isky TR-555 grind and use 0.015 which was recommended with the documentation.
Seems to work we

 

[karls59tr]

You must have the TR-555+10 Isky cam according to the chart. It seems the chart is using the .040 measurement rather than the .050 one? I"m finding it difficult to wrap my head around the whole issue.

 

[mctriumph]

Try 14 thousands but remember the ZDP in the oil above all .....
MD