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Camshaft profiles?

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burgundyben

Jedi Hopeful
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Sorry....another question..

Our car is fitted with a vented bonnet and leather strap, a 100M badge, cold air box and Le Mans carbs and manifold.

I dont know about the camshaft though, it may be a standard cam, it may be a Le Mans cam, what is the difference in lift and timing? And more to the point how different are they? what the HP gain?

whilst its all apart I thought I'd go for a lip seal conversion and a little bit of lightening of the flywheel too!

Is there what I might refer to as a 'stage1' tune? ie Le Mans cam and carbs, and 8 lbs off the flywheel? (afterall no point having a helium filled flywheel and a dopey cam)


Thanks again!

P.S. have attached a pic of the car.
 

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[ QUOTE ]
Sorry....another question.

[/ QUOTE ]
Nice looking car. I,m sure you are anxious to get it running properly.

The standard Hundred Four cam has a lift at the valve of 0.403", intake duration 230 degrees, exhaust duration of 230 degrees, overlap of 15 degrees, & rpm range of 1,000 to 4,500.

The standard LeMans cam has a lift at the valve of 0.434", intake duration 246 degrees, exhaust duration of 240 degrees, overlap of 31 degrees, & rpm range of 1,000 to 5,000.

Which cam is installed could be checked by carefully measuring the lift. Standard lift at cam would be .278", LeMans lift at cam would be .299".

The standard engine was advertised to have 90 horsepower. The LeMans engine with larger carbs, higher compression pistons, & the cam, was advertised at 110 horsepower. I can't say how much of the increase was due to the cam. There would definitely be some gain with the cam.

There should be a number of shops that can remove 8 pounds or more from the flywheel. Be sure to have the flywheel/clutch assembly rebalanced if it is lightened.

I would definitely have the crankshaft & rods checked for cracks, as the cranks are somewhat prone to cracking after being run at higher rpm's, & they are pretty old.

If you are changing the pistons, & everything will be in excellent condition, consider using pistons with slightly higher compression ratio than the standard 7.5/1 or the LeMans, nominal 8.2/1. A ratio of 9/1 would be a good target.
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