Pushrod length opinion needed
Thread Starter
Team Owner
Joined: Dec 2000
Posts: 21,092
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From: Phila., PA burbs
Pushrod length opinion needed
I'm currently in the process of final assembly on a new 383 for my 91. I'm at the point where I'm setting up my rockers. I had hopes that my old pushrods would work, but I obviously wanted to check the length to be sure. I did the marker on the top of the valve trick and the below picture is the result. The line is definitely a bit to the outside so the pushrods are a bit long, I believe. Is this enough to be concerned about? I don't have an adjustable length pushrod, but I'll order one if needed.
Safety Car
Joined: Apr 2005
Posts: 3,624
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From: Dale City VA
Your about .050 too long.... maybe .100 depeding on how mch your lifter is collasping.
I'd suggest you get an adjustable pushrod and make sure of your geometry the right way. Otherwise why even bother to check it.
Will
I'd suggest you get an adjustable pushrod and make sure of your geometry the right way. Otherwise why even bother to check it.
Will
Last edited by rklessdriver; Feb 9, 2012 at 06:52 PM.
Race Director
Joined: Apr 2000
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From: Texas
I'm currently in the process of final assembly on a new 383 for my 91. I'm at the point where I'm setting up my rockers. I had hopes that my old pushrods would work, but I obviously wanted to check the length to be sure. I did the marker on the top of the valve trick and the below picture is the result. The line is definitely a bit to the outside so the pushrods are a bit long, I believe. Is this enough to be concerned about? I don't have an adjustable length pushrod, but I'll order one if needed.
Melting Slicks
Joined: Sep 2010
Posts: 2,422
Likes: 202
the absolute best way purchase a push rod length checker.... mark the valve tips with a Permanent marker to and find dead center again... 7.192 is stock length... looks like you need shorter 7.100 - 7.185
Last edited by THE 383 admiral; Feb 9, 2012 at 06:57 PM.
Thread Starter
Team Owner
Joined: Dec 2000
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From: Phila., PA burbs
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Thread Starter
Team Owner
Joined: Dec 2000
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From: Phila., PA burbs
I'll check around. I remember seeing one somewhere that each turn of adjustment was a certain length. That would probably make it a little easier for determining the length needed.
Le Mans Master
Joined: Oct 2007
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From: Akron Ohio
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St. Jude Donor '09-'10-'11
http://www.summitracing.com/parts/CCA-7702-1/
What are you using for a lifter? You can either use the regular lifter and a light "checker spring" or make a solid lifter to use with your current springs.
Checker Spring
http://www.summitracing.com/parts/CCA-4758-2/
What are you using for a lifter? You can either use the regular lifter and a light "checker spring" or make a solid lifter to use with your current springs.
Checker Spring
http://www.summitracing.com/parts/CCA-4758-2/
Team Owner
Joined: Oct 2004
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From: altered state
St. Jude Donor '05
was just wishfully thinking someone would chime in tell me it would work fine.
Get the tool and checker spring youll be glad you did.
Dont try and turn it over with those springs on liable to snap the tool
Minor inconvenience weve all been there.
Le Mans Master
Joined: Jul 2007
Posts: 5,043
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From: Tampa Florida
There is nothing worse than having to order multiple sets of pushrods from a trial and error length guess(es) or just because your measurement was "off" a bit....@ ~$80 a set these things can add up real quick.
To avoid further confusion -you may even want to buy, borrow or steal a caliper(see below) to determine your final pushrod length instead of counting the number of .050" turns from colapsed. Use the adjustable pushrod tool to get the "length" your after then use the caliper to measure the adjusted "length" of the pushrod tool.
http://www.harborfreight.com/24-inch...per-96509.html
http://www.harborfreight.com/8-inch-...per-47260.html
Race Director
Joined: May 2001
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FWIW I'm running stock pushrod length on my car. The heads have been milled slightly, the valves have been replaced, seats re-worked, the head gaskets are different, and I'm even running 1.7 rockers. There is no way that my geometry just happens to be perfect but it's been running strong that way for a buttload of hard driven miles.
I'm a good deal older and wiser now, so if I had it to do over again I'd probably check them and get the "proper" length. Since you've already checked and know that it's wrong, might as well follow through and get exactly what you need. Being said, you could probably run them just the way they are and never have a problem. Maybe roller rockers may just be a lot more forgiving in this regard than non rollers.
I'm a good deal older and wiser now, so if I had it to do over again I'd probably check them and get the "proper" length. Since you've already checked and know that it's wrong, might as well follow through and get exactly what you need. Being said, you could probably run them just the way they are and never have a problem. Maybe roller rockers may just be a lot more forgiving in this regard than non rollers.
Thread Starter
Team Owner
Joined: Dec 2000
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From: Phila., PA burbs
I should have the adjustable pushrod today. Any recommendations on pushrods once I determine the proper length? I'm using CC Pro Magnum self aligning rockers if that matters.