View single post by Art DeKneef
 Posted: 04-03-2014 11:42 pm
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Art DeKneef


Joined: 03-12-2005
Location: Mesa, Arizona USA
Posts: 299
Let me say I am as confused as you are and am trying to figure this out on one of my cars now.

It sounds like your engine is from a 1974 car.

I'll answer what I can. The C cam is the stock cam that was standard in all JHs. There is no 104 or 107 mapping with the C cam. The 104 and 107 refer to different grinds that Lotus used in different variations of the 907, 910 and 912.

The pulleys are reversible. One side goes on the intake cam and the other side goes on the exhaust cam. Then you line up the marks accordingly. This gives you your cam timing.

You are building a 2.2 L engine with Dell 45s and higher compression. Based on what I have read and understand, you will need to use either the 104 cams, 107 cams or the 104/107 combo to get the power I think you want out of the engine. Using the stock C cams will limit the engine. But with the 2.2 crank it may be torque enough for you. I don't recall anyone doing a stock 2.0 engine to a 2.2 that didn't change cams also. If there is hopefully they will chime in and share their experience.

According to the shop manual there are 2 types of cam pulleys. The original (side 1: 110EX, 115IN - side 2: 115EX,110IN) type covers the years 1973 and 1974 up to engine 10480. After engine 10480 there is a new pulley (side 1: 110EX, 100IN - side 2: 115EX,110IN) that went on catalyst equipped cars.

If I understand you correctly on the clearance between the cams and followers, the shop manual recommends valve clearance cold of 0.005-0.007in inlet and 0.010-0.012in exhaust.