Rocker arm shims....
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From: TEXAS
Rocker arm shims.... Well, I'm trying to get the preload just right on my valvetrain 
, but I can't seem to get it 'with-in spec'. I'm using 7.40 hardened pushrods with Comp-R lifters and an aftermarket cam. 7.35 pushrods seem too small, but 7.40's are just a hair too long. Does anyone know who sells a good variety pack of shims so I can get preload correct?
Thanks,
, but I can't seem to get it 'with-in spec'. I'm using 7.40 hardened pushrods with Comp-R lifters and an aftermarket cam. 7.35 pushrods seem too small, but 7.40's are just a hair too long. Does anyone know who sells a good variety pack of shims so I can get preload correct?Thanks,
I used sheetmetal to make a couple sets until I got it right. I had the exact same problem with the same setup but heads milled .030 and stock 7.38" pushrods. Here is a chart I used. http://www.slotcar.com/drs/gachart.htm
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From: new england
Originally Posted by felton316
Well, I'm trying to get the preload just right on my valvetrain , but I can't seem to get it 'with-in spec'. I'm using 7.40 hardened pushrods with Comp-R lifters and an aftermarket cam. 7.35 pushrods seem too small, but 7.40's are just a hair too long. Does anyone know who sells a good variety pack of shims so I can get preload correct?
Thanks,
, but I can't seem to get it 'with-in spec'. I'm using 7.40 hardened pushrods with Comp-R lifters and an aftermarket cam. 7.35 pushrods seem too small, but 7.40's are just a hair too long. Does anyone know who sells a good variety pack of shims so I can get preload correct?Thanks,
I used spare Jesel shims from my SBC setup, they work very nice.
Dont Comp R lifters require adjustable rockers for proper use?
I believe that the R's require a preload between 0.000 and 0.010 max. The website says .008, but there's a little slack in there. Thats gonna be fun without an adjustable valve train.
Thats why I decided to just go with stock.
Thats why I decided to just go with stock.
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From: TEXAS
Oh, I forgot to mention that the heads were milled .030". Adjustable rockers would make this a hell of a lot easier, but I dont have $800 to drop on some new rockers right now. So I will have to shim it!
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Originally Posted by Reboot
If the heads were mille.030 the 7.35 pushrods should not be too short. Especially with CompR's.
If only took me 2 or 3 tries to get it right. They require very little preload.
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Launching!
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From: St. Louis, MO
I sure hope that you are NOT using the pushrods to set/change the pre-load because that is NOT how its done. The pushrods have absolutely nothing to do with adjusting the pre-load. The length of the pushrod is determined by where the rocker arm contacts the tip of the valve. You FIRST need to determine the correct pushrod length and then check/adjust your pre-load using shims.
Last edited by BergerMan; Jan 11, 2004 at 03:53 PM.
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Originally Posted by BergerMan
I sure hope that you are NOT using the pushrods to set/change the pre-load because that is NOT how its done. The pushrods have absolutely nothing to do with the pre-load. The length of the pushrod is determined by where the rocker arm contacts the tip of the valve. You FIRST need to determine the correct pushrod length and then check/adjust your pre-load. Once you check & adjust the first one, the rest should be the same.
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From: new england
Originally Posted by BergerMan
I sure hope that you are NOT using the pushrods to set/change the pre-load because that is NOT how its done. The pushrods have absolutely nothing to do with the pre-load. The length of the pushrod is determined by where the rocker arm contacts the tip of the valve. You FIRST need to determine the correct pushrod length and then check/adjust your pre-load. Once you check & adjust the first one, the rest should be the same.
Launching!
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From: Oceanside CA
Originally Posted by felton316
Well, I'm trying to get the preload just right on my valvetrain , but I can't seem to get it 'with-in spec'. I'm using 7.40 hardened pushrods with Comp-R lifters and an aftermarket cam. 7.35 pushrods seem too small, but 7.40's are just a hair too long. Does anyone know who sells a good variety pack of shims so I can get preload correct?
Thanks,
, but I can't seem to get it 'with-in spec'. I'm using 7.40 hardened pushrods with Comp-R lifters and an aftermarket cam. 7.35 pushrods seem too small, but 7.40's are just a hair too long. Does anyone know who sells a good variety pack of shims so I can get preload correct?Thanks,
Crane has a kit, #99179-1 that will work with bridge-type rocker assemblies (that's what we have stock). I believe these will work as they go between the bridge and the head. Give 'em a call and see if they'll work on the LS1.
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