Right, I'm building up my big valve head and I'm fitting my FR32 cam kit from my old head. As it was bought as a kit and has only covered about 500 miles I am changing the whole kit - cam, followers, posts and I'm keeping them in the order they have bedded in to. The only thing that came in the kit that I'm not changing are the new valve springs because the BV head has double springs - or should I change them for the single Kent ones?
The first thing I have noticed is that to get the correct valve clearances, all the follower posts needed to be screwed in much further than they were in my old head, 3-4 threads more in fact and most of them now have only 3-4 threads visible. I am assuming this is because the valves in my new head are longer and therefore protrude higher than the other valves did in my old head.
I have read that longer valves can upset the valve geometry and give a shorter valve lift - is that right?
What should the actual valve lift be when using a FR32 cam kit? I'm sure I read somewhere that it was around the 11mm mark. In any case, whatever it should be, they should all be the same, shouldn't they?
I havent got round to measuring the exhaust valve lift yet but these are the lift measurements for the inlet valves:
No1 9.84mm
No2 10.57mm
No3 9.81mm
No4 10.12mm
What should the actual valve lifts be? Do the exhaust and inlet valves have the same lift?
There's obviously something up there so how do I correct it? Is it a matter of grinding/filing the tops of the valve stems or the bottoms of the followers a bit at a time and re-checking the lift?
Thanks in advance
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