Sorry for hijacking..
I'm planing a 1955cc build.
I'm using standard-ish dual port heads and single barrel twin carbs,hd single springs,cm pushrods,1:1.1 rockers on abolt up shafts and a new old stock bug pack 4062 cam (I know they don't make them any more).
Any tips or advice?
Mild cams
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Marc
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- Joined: Thu May 23, 2002 12:01 am
Re: Mild cams
With .415" valve lift there's not much margin for error in the rockerarm geometry. You won't know until you put the parts together if your pushrod lengths will be correct, so budget time for futzing with that. "Swivel-foot" adjusters aren't mandatory but might be helpful, as might lashcaps. HD singles should be fine for your build; put steel shims under them so they don't chew up the heads as they rotate, .015/.020" should be enough if the valve seats aren't sunk.
If the rockers are used, they'll have wear on the sides that leaves a bump where the slit in the rocker stand is - that needs to be removed since it'll bang into the stand at the higher lift and interfere with properly setting the sideplays. Wet sandpaper on a sheet of glass works well for getting rid of it.
Be sure to use oil with a good ZDDP package like Brad Penn or Valvoline ZR-1 and don't go below ~2000RPM for the first 10-20 minutes and you should be OK using the HD springs for breakin. I won't recommend a good lifter choice since I'm not current on today's market. I think Febi are still considered OK, if a little heavy.
If the rockers are used, they'll have wear on the sides that leaves a bump where the slit in the rocker stand is - that needs to be removed since it'll bang into the stand at the higher lift and interfere with properly setting the sideplays. Wet sandpaper on a sheet of glass works well for getting rid of it.
Be sure to use oil with a good ZDDP package like Brad Penn or Valvoline ZR-1 and don't go below ~2000RPM for the first 10-20 minutes and you should be OK using the HD springs for breakin. I won't recommend a good lifter choice since I'm not current on today's market. I think Febi are still considered OK, if a little heavy.
