cam timing on a vernier wheel

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rosscoe
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Post Tue Apr 11, 2006 8:59 am

alrite guys

I need some help here,Ive got a wild cam sittin in me shed,its a piper bp285.The power band is from 2200-7000 rpm,the duration is 292 on inlet and exhaust.valve lift is 10.66mm on both.timing is 36-76,76-36, :? full lift,inlet ATDC 110deg?? :?

I understand the most of it,but for the timing and the atdc 110deg,its kinda lost me

any help would be greatly appriciated
cheers
Widge
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Post Tue Apr 11, 2006 11:15 am

As far as I understand it the 36-76,76-36 refers to the opening and closing points of the valves. So for example the inlet valve will open 36 deg before top dead centre and close 76 deg after top dead centre and vice versa for the exhavust (although I don't know which is which)
I assume you have a vernier cam pulley with the cam?
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rosscoe
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Post Tue Apr 11, 2006 12:33 pm

In the process of aquiring a vernier now.
Widge
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Post Tue Apr 11, 2006 12:36 pm

I'm not even sure if you actually need one, I would have thought the cam will have been made with the correct alignment.
I dunno hopefully someone who knows about this will come along.
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rosscoe
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Post Tue Apr 11, 2006 12:53 pm

HMM

Uve got me thinkin now widge,I thot u had to fit vernier wheels with wild cams,to get the timing rite :?
Widge
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Post Tue Apr 11, 2006 12:58 pm

Well not nessicarly, I think (although I may be wrong) that the vernier pulleys are for really wild engines so you can play with the timing, or if you have ruined the timing by decking the block etc