LT1-LT4 Modifications 1993-97 Gen II Small Block V8

pushrod length opinions

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Old 06-25-2010, 09:52 AM
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Default pushrod length opinions

I made the newb mistake of ordering pushrods without checking them. I went on someones advice that they used stock length with the cam i'm running (cc503) I have been putting it off but i went out this morning and tested. (Method:sharpie on the valve stem, installed and adjusted rocker and rotated through all four strokes twice) I only had time for one. More after work this afternoon. The mark seems to be very close to center on the valve stem, maybe just slightly toward the exhaust side of the head. What worries me is that the contact patch doesn't go all the way across the stem. Just looking for opinions on the pic and also if the method i used sounds correct. Thanks!
Old 06-25-2010, 09:57 AM
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Forgot to add that I'm running comp ultra pro mags with arp studs, hardened pushrods and guideplates.
Old 06-25-2010, 10:53 AM
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your PR length check method is correct. what I see is the "allignment L to R of the RR may be off. ISKY adjustable guide plates should solve that by allowing you to line up each RR dead nuts on the valve stem tip.

regarding the length...the marks show the 7.200" (stock) as being "slightly" long. 7.150" may be the ticket but a PR check tool would confirm.
Old 06-25-2010, 11:56 AM
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Originally Posted by ******
your PR length check method is correct. what I see is the "allignment L to R of the RR may be off. ISKY adjustable guide plates should solve that by allowing you to line up each RR dead nuts on the valve stem tip.

regarding the length...the marks show the 7.200" (stock) as being "slightly" long. 7.150" may be the ticket but a PR check tool would confirm.
agree with the l to r alignment, as for the length if it was my car i would leave the 7.2's in
Old 06-25-2010, 01:02 PM
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Length looks good to me if they are slightly to the exhaust side.
Old 06-25-2010, 10:57 PM
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Ok thanks alot guys. I feel better now ha. i never even knew adjustable guideplates existed. I wonder why the ones I have don't work? just curious...
Old 06-25-2010, 11:21 PM
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Did you make that lifter solid before performing the test?
Old 06-26-2010, 04:05 PM
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no i didn't... I was thinking about that yesterday. Maybe it wasn't pumped up. How do you "make" a lifer solid? I did soaked them before i installed them.

Last edited by ebeard; 06-26-2010 at 04:12 PM.
Old 06-26-2010, 04:11 PM
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you disassemble the lifter and put something solid in i and reassemble it
Old 06-26-2010, 06:12 PM
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Originally Posted by speed_demon24
Did you make that lifter solid before performing the test?
Correct question. You have to use a solid lifter, an adjustable pushrod length checker to measure correct pushrod length. If the heads are not milled, with that cam, stock length pushrods-7200" shouldn't be an issue.
Old 06-26-2010, 10:47 PM
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Yeah i guess it was fine the way it was, but atleast i learned something. Also spent half an hour in the grass tonight trying to find part of the lifter i dropped on the way back in the house lol
Old 06-27-2010, 08:55 AM
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Originally Posted by ebeard
Ok thanks alot guys. I feel better now ha. i never even knew adjustable guideplates existed. I wonder why the ones I have don't work? just curious...
Well, what guideplates do you have? Maybe they are not the right ones.
Old 06-27-2010, 09:02 PM
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Guideplates used: http://www.summitracing.com/parts/TFS-30400623-8/
Old 06-27-2010, 10:43 PM
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Originally Posted by ebeard
Hmm...most people seem to use those without issue.
Old 06-27-2010, 11:16 PM
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i run those guideplates aswell... dont have problems with them
Old 06-28-2010, 04:44 PM
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Circle Track magazine and others as well disagree with the solid lifter approach to finding the correct pushrod length. Well, unless it's a solid lifter cam, of course, and then zero lash is used. With a hydraulic cam all you do is use the stock lifter and even set the preload.

I can post the link to the article if verification is needed.

I wonder who came up with the idea that you have to pull the intake manifold to find the correct pushrod length anyway. Seems that it's one of those things that got started, then was just passed around.

Jake
Old 06-28-2010, 04:51 PM
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Originally Posted by JAKEJR
Circle Track magazine and others as well disagree with the solid lifter approach to finding the correct pushrod length. Well, unless it's a solid lifter cam, of course, and then zero lash is used. With a hydraulic cam all you do is use the stock lifter and even set the preload.

I can post the link to the article if verification is needed.

I wonder who came up with the idea that you have to pull the intake manifold to find the correct pushrod length anyway. Seems that it's one of those things that got started, then was just passed around.

Jake
They have been saying this for years and many people have been doint this without problems.. People have also been only using the stock lifter and still the same results. I guess its more for people that are not good with adjusting the correct preload to get the precise measurement for the correct pushrod. But to each is own and I just use a solid lifter that I have laying around. When you do a cam swap, the intake comes off anyway. So why not check it and replace P.r if needed.
Old 06-28-2010, 07:58 PM
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Originally Posted by ebeard
Speedinc had to modify mine a bit to get it perfect. Never really double checked to see what they actually did though.



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