My gasket set has come with 8 small and 16 large valve stem seals but nothing to say which to use. Does anyone know which ones I should use and where?
The set is for 318, 340 and 360 motors, mine is a 340
They all seem to fit and my guess would be that the retained type might go on the inlet valves because the old larger ones are grooved and grip the stem guide in the block. The old smaller ones do not and they were on the exhaust valves.
The first one is positive type seal the best type as they clip onto the valve guide, most times you need the guides with a groove for them to click into, (stock type may not) and fitted to the inlet as it needs less lubricant due to less heat but more vacuum. The others are the stock type that fix to the valve stem and ride up and down with the valves, the taller one is inlet and the smaller umbrella is for the exhaust smaller for more lubrication and heat protection, the second from left (16 of) can be used for either in your kit. You are quite correct with your assumption. Hope this helps
Petty Roadrunner 416 Stroker 4 Speed
*MMA-609*
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