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autogateman
MMT Sponsor
Joined: Thu Sep 16, 2010 10:32 pm Posts: 4036 Location: Gonzales La
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 determining connecting rod length
i just bought a motor that has evt connecting rods, and am trying to figure out if theyre the stock length or not because i am going to sell them. mike at evt said the longer ones would only be used on shaved pistons, but they dont appear to be shaved. yeah i know it seems to answer my own question, but this motor has every part evt sells/sold and cant imagine that they changed everything BUT the pistons. i just dont wanna sell somebody these thinkin they are factory length and they install them and cause damage. is there a way to measure them? thanks,Rod
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Tue Nov 30, 2010 5:53 pm |
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BradS
MMT 1000 Club
Joined: Wed Jan 14, 2009 5:23 am Posts: 4514 Location: Lafayette, La
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 Re: determining connecting rod length
With a ruler
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Wed Dec 01, 2010 7:44 am |
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MaXXis85
MMT Elite Member
Joined: Wed Jan 14, 2009 7:23 am Posts: 6233 Location: Tarkington, TX
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 Re: determining connecting rod length
There are enough folks on here with blown up motors they can measure a stock rod for ya. You need something more accurate than the ruler ur 3rd grade teacher gave ya.
_________________ Bayou Surface Drive 337-351-0362 Tarkington, TX 77327
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Wed Dec 01, 2010 7:49 am |
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BradS
MMT 1000 Club
Joined: Wed Jan 14, 2009 5:23 am Posts: 4514 Location: Lafayette, La
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 Re: determining connecting rod length
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Wed Dec 01, 2010 8:00 am |
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UNCLE-J
MMT Sponsor
Joined: Fri Jul 24, 2009 7:26 am Posts: 10388 Location: S-Ville, LA
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 Re: determining connecting rod length
The most common reasons for using a pushrod that is longer or shorter than stock are: a decked cylinder block or heads, thicker/thinner head gaskets, small base-circle camshafts, aftermarket rocker arms, longer-length valves, valve jobs with varying seat depth, non-stock lifter designs and/or seat height, and converting to an adjustable valvetrain. These variables inevitably alter pushrod length; however, following these easy steps will help prevent improper geo-metry and ensure your engine's longevity.
Zero out the Comp Cams pushrod length-checking tool, ( http://www.summitracing.com/parts/CCA-7709-1 ) then install it in the lifter's pushrod seat and within the pushrod guide plate on the cylinder head (if applicable).
If your camshaft requires valve lash (our mechanical roller cam calls for 0.012 inch), insert the proper feeler gauge between the rocker-arm tip and the valve tip.
If the rocker-arm tip is beyond the 11/43-forward position, you need to return the lifter to the cam base circle, shorten the adjustable pushrod, and slightly loosen/tighten the rocker-arm adjustment nut (changing the initial 11/43-forward position). Next, readjust the checking-tool length so that it achieves zero lash on the backside of the rocker arm. Then roate the engine through its firing in order to note movement range of the rocker-arm tip.
While holding up the pushrod end of the rocker arm, turn the rocker adjustment nut so that the rocker-arm tip is approximately at the 11/43-back position on the valve step tip. Note: the more you tighten the rocker adjustment nut, the further it moves the rocker-arm tip toward the 11/43-back position.
Rotate the engine through its firing order to open the valve as cam lobe increases. Stop when the cam lobe is at maximum lift. As the lobe lift increases, the rocker arm should move toward the opposite side of the valve tip (the 11/43-forward position).
Note how many turns out from zero the tool is. For each 360-degree rotation of the threaded end (adjustment amount indicated by thin white lines), add 0.050 inch to the measurement. For example, this checker tool (PN 7994-16) has a 7.80-inch length when zeroed out. To that we added three turns out (0.050 inch x 3) from zero, which brought us o a final length of 7.950 inches.
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Wed Dec 01, 2010 8:08 am |
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BROOKS
MMT 1000 Club
Joined: Tue Jan 13, 2009 9:46 pm Posts: 4596 Location: East TEXAN Proud
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 Re: determining connecting rod length
_________________ Git a Gator-Tail or ride in mines wake ...... MtrFact !!!!! '05 Model .... Still Number One on the Water !!!!
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Wed Dec 01, 2010 9:23 am |
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JIMMY W
MMT 1000 Club
Joined: Tue Jan 13, 2009 8:02 pm Posts: 4534 Location: South Louisiana
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 Re: determining connecting rod length
Push Rods???? 
_________________ 17/54 GT EXTREME Center Console, Huntdeck w/ GTR 35
Hoyt Mods and some other goodies
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Wed Dec 01, 2010 10:00 am |
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quackconsumer
MMT Elite Member
Joined: Wed Jan 14, 2009 7:54 pm Posts: 5582
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 Re: determining connecting rod length
I thought we were talkin bout connectin rods?
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Wed Dec 01, 2010 10:05 am |
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MaXXis85
MMT Elite Member
Joined: Wed Jan 14, 2009 7:23 am Posts: 6233 Location: Tarkington, TX
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 Re: determining connecting rod length
_________________ Bayou Surface Drive 337-351-0362 Tarkington, TX 77327
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Wed Dec 01, 2010 10:39 am |
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autogateman
MMT Sponsor
Joined: Thu Sep 16, 2010 10:32 pm Posts: 4036 Location: Gonzales La
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 Re: determining connecting rod length
nice try J, but yes, i am talkin bout connectin rods
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Wed Dec 01, 2010 10:40 am |
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UNCLE-J
MMT Sponsor
Joined: Fri Jul 24, 2009 7:26 am Posts: 10388 Location: S-Ville, LA
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 Re: determining connecting rod length
sorry.. I was just trying to be a Smart Azz in a very short time..
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Wed Dec 01, 2010 10:44 am |
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take'emgator
MMT Super Elite Member
Joined: Mon Oct 19, 2009 6:38 pm Posts: 10201 Location: SETX
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 Re: determining connecting rod length
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Wed Dec 01, 2010 11:00 am |
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craig
MMT Elite Member
Joined: Tue Jan 13, 2009 7:53 pm Posts: 7515 Location: Chauvin
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 Re: determining connecting rod length
What's the wristpin diameter?
_________________ 1750 GatorTail Extreme/Stage 3 37 GTR HD Procrastination is a lot like masturbation. Sure it sounds great at the time but, in the end your only f--k--g yourself.
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Thu Dec 02, 2010 10:30 am |
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autogateman
MMT Sponsor
Joined: Thu Sep 16, 2010 10:32 pm Posts: 4036 Location: Gonzales La
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 Re: determining connecting rod length
nevermind guys, stock length
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Thu Dec 02, 2010 9:04 pm |
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