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racing97 racing97 is offline
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Join Date: Mar 2004
Location: So. Ca.
Posts: 477
Quote:
With the height correct, and the new valve spring fitted, should i be able to rotate the springs
The answer is no.
The basic setting for a spring is its proximity between the coils with safety in mind this would be 1.25mm. To measure this you can do some ghetto math on the cam by measuring the highest point on the lobe and subtracting it from the narrowest and multiplying it by the rocker ratio 1.45 that will give you the number you need. Now you need to either come up with a vernier that will give you a comfortable sense of accuracy or sacrifice a retainer by cutting a notch in it so that you can measure from the bare head or perch to the top of the installed retainer on the valve. This will provide you the base installed height. Take the spring, retainer and spring seat over to a vise and with the cam lift compress the spring package to the cam lift then compress it to solid height the remaining clearance less 1.25 mm in total will be your shim height if it is a huge push rod after market spring you will have too much seat pressure but if it is a porsche spring this will give you everything much fancier equipment will and if you come to a spring the requires many more or less shims you probably should replace it. You will be somewhere between 60 and 70lbs on the seat.
This procedure will work in a pinch on anything;
regards
Old 05-28-2018, 11:17 AM
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