7 replies to this topic

[tb205gti]

Hi, I have a cam for the engine I'm building - I always thought it was a Kent 276 - but now I'm not so sure. It has "276" engraved, but looks like a regrind from an original cam. (1 raised ring between lobe 5&6)

Lift is 7.4mm on the exhaust and 7.7 on the inlet - but i do not know the seperation angle, timing, nor the full lift angle. 

 

..So what do I aim for when setting it up? 106 deg like the KentCams 276? Or do i fit a dial gauge on the cam once in the engine (no head or pushrods fitted, so I can spin it freely) and then start measuring? (What lift is the duration on the KentCam measured, and is it cam lift or valve lift that is used?)

 

 

[nicklouse]

lets see the 276 marking.

[tb205gti]

lets see the 276 marking.

I'll try but it has been fitted to the engine - so har to get a picture of it :/

[nicklouse]

s

 

 

lets see the 276 marking.

I'll try but it has been fitted to the engine - so har to get a picture of it :/

 

but if you are doing the timing you should have it right infront of you as they stamp the timing end of the shafts

eg

[mini13]

measure it,

 

check where its timed on the inlet as per normal, and then pull the DTI off and check it on the exhaust lobe, you'll then be able to work out the LCA,

 

Also, its definatly worth puting the DTI on each lobe in turn, zeroing it on the base circle and checking what lift you get on each lobe, this is a good way of checking cam wear on a built engine.

 

If you want to get really fancy, you can plot the lift every 5 degree's and tick it into an excel spreadsheet to get a nice graph,

 

also I'll add that most cams are timed "straight up" so for a 276 witha 106 LCA, it would be timed at 106 degree's so exhaust is open 106 btdc, and inlet 106 deg after, and depending on your needs you can go either side of that a couple of degree's. generally advancing will pull the bottom end up at the expense of top end, and visa versa.

Edited by mini13, 03 May 2018 - 08:48 AM.

[tb205gti]

I have measured the lift on each lobe - and it is "as expected". The cam is brand new - have never been used - so no wear.

 

@nicklouse: If there was a stamp in the end it would be easy to identify, but there isn't. :/

[carbon]

OP - you mention that lift is 7.4mm on the exhaust and 7.7 on the inlet - is this lobe lift (ie lift measured at the pushrod) or the actual valve lift?

[Retroman]

I would have been measuring it before putting it in

 

If its not marked KC +++  its not Kent, they have been marked KC for what over 40 years ?