7.235 PR length???
#1
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7.235 PR length???
so i measured the PR on the heel of the cam. snugged down the rockers. twisted the PR length checker. got out my digital calipers and measured. i come up with 7.235. does that sound right?? then if i add the .060 preload for the cadillac lifters i get 7.295
Last edited by pdd; 01-15-2007 at 03:29 PM.
#2
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If you're running an XE-R cam, you typically need to run a .050" longer pushrod than stock to maintain the .100" factory plunger depth. Milled heads, thinner gaskets and different lifters will change this.
With your combination:
.030" mill
.040" gaskets
.060" plunger depth
A 7.350" pushrod is the closest thing that will give you the .060" plunger depth.
With your combination:
.030" mill
.040" gaskets
.060" plunger depth
A 7.350" pushrod is the closest thing that will give you the .060" plunger depth.
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2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
#4
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Originally Posted by pdd
why the heck am i so far off?
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2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
#6
Originally Posted by pdd
why the heck am i so far off?
Open the checking pushrod to the length you came up with by adding .060 and then see how many turns of the factory rocker bolt from the basecircle to fully tightened (representing the pushrod preload). If your measurments are right I bet you will be a little over one full turn from zero lash to fully tightened. If thats the case you are good to go although I would run a little more preload (closer to .100 which is a little less than two full turns) for an even quieter valvetrain). Make sure you are on the heel of the cam (basecircle) on the cylinder you are checking...
Tony M.
PS...What rockers are you running?....stock??
#7
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How are you measuring the length of the adjustable? You need to use the indicator on the side (two opposing white lines), with each turn equal to 0.050" longer in pushrod length. If you are using the Comp pushrod with the 6.800" base length, then 10 turns would be 7.300" pushrod length. Note also that the pushrod measurement is done in gauge length, not what you measure with a tool like a vernier.
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#9
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Originally Posted by vettenuts
How are you measuring the length of the adjustable? You need to use the indicator on the side (two opposing white lines), with each turn equal to 0.050" longer in pushrod length. If you are using the Comp pushrod with the 6.800" base length, then 10 turns would be 7.300" pushrod length. Note also that the pushrod measurement is done in gauge length, not what you measure with a tool like a vernier.
#10
Originally Posted by Tony Mamo @ AFR
Pat...
Open the checking pushrod to the length you came up with by adding .060 and then see how many turns of the factory rocker bolt from the basecircle to fully tightened (representing the pushrod preload). If your measurments are right I bet you will be a little over one full turn from zero lash to fully tightened. If thats the case you are good to go although I would run a little more preload (closer to .100 which is a little less than two full turns) for an even quieter valvetrain). Make sure you are on the heel of the cam (basecircle) on the cylinder you are checking...
Tony M.
PS...What rockers are you running?....stock??
Open the checking pushrod to the length you came up with by adding .060 and then see how many turns of the factory rocker bolt from the basecircle to fully tightened (representing the pushrod preload). If your measurments are right I bet you will be a little over one full turn from zero lash to fully tightened. If thats the case you are good to go although I would run a little more preload (closer to .100 which is a little less than two full turns) for an even quieter valvetrain). Make sure you are on the heel of the cam (basecircle) on the cylinder you are checking...
Tony M.
PS...What rockers are you running?....stock??
#11
Originally Posted by jetblast
that's the method i used to come up with .350 push rd. my preload was 1.75 turns, now is 1.25 turns and my valvtrain is much quieter.
Tony
PDD....Gotcha on the rebuilt stock rockers....they should work fine.