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> Rocker geo, hoe does this look to you guy's
toon1
post Oct 28 2007, 09:04 PM
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so far the liift is good, cam card say's .426, I've got about .428.

Here is a pic. with the vave at half lift. Seems a little off(leaning back) to me.


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HAM Inc
post Nov 1 2007, 05:02 PM
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The geometry in the last photo looked a lot better.

Clayton is correct that the valve stems all need to be level. If they are off it will effect valve timing. The biggest impact will be on the cross-over point. This is the point during intake and exhaust valve overlap when the exhaust is closing and the intake is opening, but both are off their seat the same amount. This is an extremely critical point in the engines cycling. Sharp race engine builders will check the cross over points on each cylinder (requires a dial indicator on each valve) to ensure that they occur within a * of each other, that's + or - 0.5 *. No point spending the bucks on the cam and all of the other innerds if the valve stem ht's are all whacked. I guarantee the stem ht's on every head that leaves my shop are + or - .005" of each other.

Here's a trick for setting geometry that de-confuses the relationship between pushrod length and rocker shims. Remove the valve springs. Purchase a couple of shaft collars that are the size of your valve stems. Set the head on a bench with the valve stems up. Slide the collars over the valve stems (one for intake and exhaust) and set them so they will hold the valves open at half lift. A caliper works fine for this. With the valves in the half lift position set your rocker assembly in place with the valve adjuster locked where you want it. Now just keep adding shims until you have the proper geometry, which is the adjuster in line with the valve. If the intake and exhaust have different lifts you may have to make adjustments to one of the adjusters to level them both out. You may also have to make adjustments to your screws if the first positions you try are in-between what you can level with the available shims. Once you have that worked out, set the head on the engine and bring your adjustable pushrod in, adjust it to take out the slack. Now you have the correct shims for proper geometry and pushrod length to fit the space.
This works because the pushrod has nothing to do with proper geometry. The proper geometry is a function of the relationship between the rocker arm and the valve, period. This would be easier if the adjusting screw was in the pushrod side of the rocker like HP domestic rockers and some hi-lift rockers.
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toon1   Rocker geo   Oct 28 2007, 09:04 PM
toon1   here are somemore pics of the spacers. notice the ...   Oct 28 2007, 09:20 PM
toon1   one more   Oct 28 2007, 09:20 PM
Twystd1   Did you mill your rockers about 60 thou for those ...   Oct 28 2007, 11:16 PM
Joe Ricard   Hey what kinda push rod is that? Did you make on...   Oct 29 2007, 06:08 AM
TC.356   Shims beneath the rocker assemblies and longer (ad...   Oct 29 2007, 07:34 AM
toon1   Hey what kinda push rod is that? Did you make o...   Oct 29 2007, 09:29 AM
George H.   You mentioned oil for the rockers, should it ...   Oct 29 2007, 10:33 AM
orange914   I placed the dial indicator back into positio...   Nov 3 2007, 12:03 AM
craig downs   where axactly does the indicator go? wouldnt anyw...   Nov 3 2007, 12:48 AM
Joe Ricard   I oil the rocker shafts with the same oil I do eve...   Oct 29 2007, 10:26 AM
toon1   there is oil on the rocker shafts, I didnt' oi...   Oct 29 2007, 11:24 AM
Joe Ricard   What really want to know is how much of a clearanc...   Oct 29 2007, 11:44 AM
toon1   here are some more pics. I added .030 shims under ...   Oct 31 2007, 12:23 AM
toon1   2 more   Oct 31 2007, 12:24 AM
Twystd1   Uhhhh... 1) Are you setting up your rocker GEO at...   Oct 31 2007, 01:13 AM
toon1   Uhhhh... 1) Are you setting up your rocker GEO a...   Oct 31 2007, 11:15 AM
toon1   :bump: el bumpo thank's guy's   Oct 31 2007, 07:52 PM
Twystd1   Do me a favor..... Throw a straight edge across A...   Oct 31 2007, 08:47 PM
toon1   with the sraight edge on the tops of the valve ste...   Oct 31 2007, 10:20 PM
Twystd1   Your gaps are survivable. If ya want it perfect. ...   Nov 1 2007, 12:16 AM
craig downs   ahhhhh I guess its time to say something and proba...   Nov 1 2007, 01:29 AM
toon1   thank's guy's, I will give that a try. ...   Nov 1 2007, 09:59 AM
Joe Ricard   That extension thing on the Rocker adjuster is pur...   Nov 1 2007, 10:27 AM
Joe Ricard   Bump for the evening crowd. Obviously the day su...   Nov 1 2007, 03:39 PM
HAM Inc   The geometry in the last photo looked a lot better...   Nov 1 2007, 05:02 PM
toon1   thank's for the reply and the good info. H...   Nov 1 2007, 05:43 PM
Twystd1   Do not take any more than about 60 thou off the ro...   Nov 1 2007, 09:19 PM
Twystd1   CRAIG..... Post up pics of your PS tool / arrange...   Nov 1 2007, 09:28 PM
toon1   I took another .020 off the rocker. I got your pos...   Nov 1 2007, 11:18 PM
Twystd1   Since your engine was't machined perfectly to ...   Nov 1 2007, 11:45 PM
toon1   Since your engine was't machined perfectly to...   Nov 2 2007, 12:26 AM
craig downs   Ok I'll try to get some pics tomorrow. Hmmm p...   Nov 2 2007, 03:08 AM
Twystd1   TOON, A half a MM is way to much to average Do e...   Nov 2 2007, 02:27 PM
purple   I guess it's kindof a newbie question and all,...   Nov 2 2007, 03:33 PM
toon1   TOON, A half a MM is way to much to average Do ...   Nov 2 2007, 08:27 PM
Twystd1   Excellent job Keith.....!!!!!...   Nov 2 2007, 09:54 PM
toon1   DO those #'s look good? Thank's for the...   Nov 2 2007, 10:55 PM
Twystd1   Keith, YOU WILL HAVE TO START OVER ON YOUR GEO WI...   Nov 3 2007, 12:02 AM
toon1   Thank's Clayton, I'll wait till the cyl...   Nov 3 2007, 12:26 AM
Twystd1   To the guy that just PMed me about how to INSTALL...   Nov 3 2007, 01:00 AM
toon1   To the guy that just PMed me about how to INSTAL...   Nov 3 2007, 09:45 AM
HAM Inc   Been out of town for a few days, so I just got up ...   Nov 5 2007, 03:10 PM


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