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Tim Orme
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Hi, wondering if anyone can advise. New to the message board so if the topic's been covered before, forgive me !

I have a set of Lotus Excel SE cams / housings (107/104 combination), I'm intending to fit them to my standard U.K. spec 907 engine and move to an HTD belt / vernier pulley set. Will these cams be worth using in my engine or should I put my standard cams into the Excel housings. What cam timing figures should I use. Any advice appreciated

 

Tim

Greg Fletcher
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The 107/104 combo with vernier pulleys is a very cool setup. There are a number of great posts on the board, try the search feature and see what comes up.

You'll be looking for a 104 MOP to really take advantage of what the cams can offer and needless to say a 2.2 would provide the best basis for that. Some among us would say you simply must have the 2.2, but I think the standard 2 liter can still offer enough to make your switch well worth the effort.

Tim Orme
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Thanks for the advice Greg, funds won't stretch to a 2.2 conversion at the moment but it's something that I will be considering in the future.

Jensen Healey
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The 104 cam will cause binding of the stock valve springs. You will need to either change the springs to the performance version or use a milder cam.

I have been taking baby steps with performance upgrades. I have a pair of 107 cams but I know that installing them and getting them shimmed could have the car down for weeks. Most of the time is spent waiting for shims. I also have not purchased any 104 pulleys but have a set of 102's from a later JH.

Then there's the re-tuning of the Dellortos....

Call me lazy,

Kurt

JH 13148

Tim Orme
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Thanks Kurt, that's something I hadn't considered ! So it's head off as well then (just changed the head gasket - typical) Wanted to use the later cam housing to eliminate the oil leaks once and for all - can't seem to make the re-useable gaskets seal properly and each time you want to check the valve clearances, it's oil over the manifold (sorry - headers)  time !

 

 

Jensen Healey
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It would be cheaper to use two 107 cams and skip the cost of new springs, head gasket, exhaust gaskets, and intake gasket. 

Just a note on valve adjustment, shoot for the high side on the clearance. The clearances only get tighter and it should stay within tolerance longer.

Kurt

LambandAndy
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I have removed valve springs on other engines by making an adapter to screw into a spark plug hole and applying compressed air to keep the valve in place while using an "overhead" style valve spring compressor to remove the collets.

Never tried it on a Lotus motor but it should work.

Andy



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