Timing belt a non-standard pitch?
#1
Three Wheelin'
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I just measured the timing belt pulleys on my 87 project engine, not to re-invent the wheel but possibly make new pulleys. I expected a 10mm pitch but the diameter of the pulleys and number of teeth imply a 3/8" pitch instead. Am I crazy? Could Porsche have specified an inch size belt?
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When you can BUY new cam gears which we KNOW work for like $112 each WHY would you want to guess at the proper material and go to all the effort of making them finishing the surface then proving over many years of driving that they worked.... I guess I could plow a field plant wheat grow a crop grind the grain and make bread but WHY ?
#6
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I think they are actually a standardized metric HTD design
I agree with Jim if your intent is to make an identicle gear.
But if you make one that makes cam timing adjustments easier and tooless then maybe I this would be worth it...
LO
I agree with Jim if your intent is to make an identicle gear.
But if you make one that makes cam timing adjustments easier and tooless then maybe I this would be worth it...
LO
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#8
Three Wheelin'
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Originally Posted by Jim bailey - 928 International
When you can BUY new cam gears which we KNOW work for like $112 each WHY would you want to guess at the proper material and go to all the effort of making them finishing the surface then proving over many years of driving that they worked.... I guess I could plow a field plant wheat grow a crop grind the grain and make bread but WHY ?
Glen, the gears are aluminum except for the crank gear which is steel. For measuring, multiplying the pitch by number of teeth gives you a circumference which the diameter can be deduced from, the difference between 3/8" and 10mm is significant in overall diameter, much more than differences of peak and root of the groove.
#10
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Originally Posted by Jim bailey - 928 International
When you can BUY new cam gears which we KNOW work for like $112 each WHY would you want to guess at the proper material and go to all the effort of making them finishing the surface then proving over many years of driving that they worked.... I guess I could plow a field plant wheat grow a crop grind the grain and make bread but WHY ?
#12
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Originally Posted by Mike Simard
I've considered making gears in order to have a more durable coating, probably hard anodising.
#13
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Originally Posted by Jim bailey - 928 International
I guess I could plow a field plant wheat grow a crop grind the grain and make bread but WHY ?
#14
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Originally Posted by Shark Attack
why did we fly to the moon? we sure didnt bring back anything of value