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Wedge Pulley

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MadMarx

MadMarx

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I'm still not happy about the temperatures of the engine so I've looked around and found many race engines with 1:1 ratio between crank pulley and water pump pulley.
My pump currently is underdriven 0,81.
I make the pulley on the pump a little smaller to speed it up, maybe this helps to cool the car.



13233118_1039522646082909_9084859164544507975_n.jpg


 
I'm allowed to but the car never had, so it remains with a belt driven pump.
Somehow it is impossible to find the diameter of the standard pulleys. Nothing on the web to find.

I've finished the work on the new pulley. half the weight of the other one.
13312702_1039906886044485_611065605756406444_n.jpg
 
My cast iron pulley on a TR3A is 0.75"wide and 4.234" OD

Why the 2 belts to the water pump? They slip at higher RPM?

David
 
2 belts?
You mean instead of 1 to go around all 3?
 
DavidApp said:
.....
Why the 2 belts to the water pump? They slip at higher RPM?

David
Click to expand...

The old configuration from Canada drove with one belt crank an pump, and a second belt was going from pump to alternator.
The new pulley I've made is of smaller diameter to speed the pump up and I made the pulley in such way that all groves are inline so that I can use several ways of driving them. I can use different combinations of belts. Changing the diameters means different lengths of belts and I wasn't sure to find a fitting one.

Why two belts to the pump:
1. two belts mean less tension to each belt. The original configuration was strapped down very hard and I feared to break the housing or the pump shaft or wear out a bearing
2. if one belt jumps off, one belt is still driving the pump as the most vital item on the engine next to the oil pump.
3. Same if one belt breaks
 
Hello Don/Marx

That is what I had assumed. the belt that goes around only 2 pulleys will get better grip due to the wraparound.

Nice work.

David
 
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