Author Topic: valve adj  (Read 3191 times)

68Zproject

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Re: valve adj
« Reply #15 on: June 10, 2014, 10:27:47 PM »
Stock 302 other than the cam, lifters and rockers.  I have roller tipped 1.52's.  That thing really went a lot better than the engine I had with the LT1 cam.  In fact when I got the heads, they were supposed to have had the intake unshrouded as they were 1.94's, but I noticed it hadn't been done so I had it done when I got the heads fixed. The heads were also ported.  3.73 rear and m21.  No dyno in the budget.
68Z28

ko-lek-tor

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Re: valve adj
« Reply #16 on: June 10, 2014, 11:59:40 PM »
You may want more gear or an M20, IMO.
Putting you First...Keeps me First. Talent on loan from God. Helping the hobbyist and exposing the fraud
1969 SS/RS 396 coupe Hugger Orange X22 712 bought in 79
1969 SS 350 coupe LeMans Blue 713 bought in 79
1969 307 4spd. coupe Daytona Yellow 711 bought in 85

69Z28

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Re: valve adj
« Reply #17 on: June 11, 2014, 08:07:23 PM »
I have to agree with Bentley on the M20. Works great with 3.73's and 4.10's in first gear. Don't seem to have that kind of lag the M21 has in first gear. 2nd thru 4th should be the same IIRC. For the my car launched pretty well with the 4.10's, kind of like a punch in the face. With the 3.73's now back in it's much less of a shock on launch. Much smoother.       
GaryC

'UNRESTORED' 1969 Cortez Silver X33D80 Z28

hotrod68

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Re: valve adj
« Reply #18 on: June 12, 2014, 01:58:58 AM »
  For anyone reading who has a hydraulic cam, I have a foolproof method of adjusting juice lifters. Use the sequence as suggested above by cook. To adjust the valves, back off of the rocker arm until you can spin the pushrod between your fingertips. Then slowly tighten the nut down until the pushrod stops rotating. Turn the nut EXACTLY one-eighth of a turn and your hydraulic lifter is set. Do not go 1/4-turn. I've found that with a performance or even stock cam, this sets the lifter preload perfectly. Hope this helps someone.
HotRod'68  1968 SS350 coupe undergoing frame-off resto/rod. 386/350/4.11s
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Mike S

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Re: valve adj
« Reply #19 on: June 12, 2014, 02:18:02 AM »
 For anyone reading who has a hydraulic cam, I have a foolproof method of adjusting juice lifters. Use the sequence as suggested above by cook. To adjust the valves, back off of the rocker arm until you can spin the pushrod between your fingertips. Then slowly tighten the nut down until the pushrod stops rotating. Turn the nut EXACTLY one-eighth of a turn and your hydraulic lifter is set. Do not go 1/4-turn. I've found that with a performance or even stock cam, this sets the lifter preload perfectly. Hope this helps someone.
Lots of room for hydraulic installs....
Every BB hydraulic cam I put in I did the following:

Coat base with moly-lube and install lifters  (Soak in oil over night but do not pre-pump prior to installing)
Rotate engine to get the lifter on the lobe bottom
Turn the rocker arm adjusting nut until the lifter plunger moves about 1/16" down from the plunger retainer

At this point you can fire up the motor and usually do not have to adjust them afterwards.

Mike
67 LOS SS/RS L35 Hardtop - Original w/UOIT
67 NOR SS/RS L35 Convertible - Restored

hotrod68

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Re: valve adj
« Reply #20 on: June 12, 2014, 04:54:43 AM »
  Mike............that 1/8 turn roughly equals 1/16". And yes....once you fire it up they don't need adjusting again. It sets the lifter plunger just right to eliminate pump-up when you spin the engine up.
HotRod'68  1968 SS350 coupe undergoing frame-off resto/rod. 386/350/4.11s
Butternut Yellow    black standard interior

68Zproject

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Re: valve adj
« Reply #21 on: July 04, 2014, 04:05:06 PM »
Just a follow up.  Got the car running yesterday ( after a whole day of cursing as my Pertronix distributor seemed to be the reason it didn't start) and when I went to adjust the valves when hot, they were right on at about .016.  I lashed them cold at .018.  Some had to be tweaked a hair tighter or looser, but the cold .018 was pretty close.  Thanks all who contributed.  It's great to be on the road again.
68Z28