Just another Push rod question!!!!
Just another Push rod question!!!! I have a torquer V3 cam with PRC LS6 2.5 heads milled to 61cc, engine is stock block so no decking was done. When I used a PR checker it said I needed a 7.375 pr (.075 preload added on) or close to it. I have both 7.400 pr's (TSP recomended) and 7.375 pr's as well. What I have found is when I use the 7.400 pr's. The intake valves go 1 1/4 to 1 1/2 turns to 22 ft/lbs. and the exhaust valves go to 1 3/4 to 2 turns. When I use the 7.375 in both exhaust and intake, the Intake goes 1 turn or so and the exhaust runs down to 1 1/4 to 1 1/2 turns. So what I did was used 7.375 in the exhaust valves and the 7.400 in the intake valves. My question is does the Torquer V3 have two different base circles on the intake verses the exhaust. My guess would be yes based on what I have done here. I would also guess this based on the lift value that the intake is running (.643) verses the exhaust (.598) I assume the lift being higher then (+.600) makes this lobe have a smaller base circle than the exhaust. true?
Thanks in advance
Troy
Thanks in advance
Troy
Last edited by 1NASTYZo6; Apr 24, 2010 at 08:23 PM.
I have a torquer V3 cam with PRC LS6 2.5 heads milled to 61cc, engine is stock block so no decking was done. When I used a PR checker it said I needed a 7.375 pr (.075 preload added on) or close to it. I have both 7.400 pr's (TSP recomended) and 7.375 pr's as well. What I have found is when I use the 7.400 pr's. The intake valves go 1 1/4 to 1 1/2 turns to 22 ft/lbs. and the exhaust valves go to 1 3/4 to 2 turns. When I use the 7.375 in both exhaust and intake, the Intake goes 1 turn or so and the exhaust runs down to 1 1/4 to 1 1/2 turns. So what I did was used 7.375 in the exhaust valves and the 7.400 in the intake valves. My question is does the Torquer V3 have two different base circles on the intake verses the exhaust. My guess would be yes based on what I have done here. I would also guess this based on the lift value that the intake is running (.643) verses the exhaust (.598) I assume the lift being higher then (+.600) makes this lobe have a smaller base circle than the exhaust. true?
Thanks in advance
Troy
Thanks in advance
Troy
I just installed a TSP 233/239 596/605 on a 112 with 5.3L Stage 2.5 heads that were milled .023. We ended up a little less than 1.75 turns to get to full tq. (about 1 2/3). It is nice and quiet with this setup.
My setup used 7.375 pushrods. I tried 7.400 and they ended up with 2.25 turns to full tq. 7.350 would have put me right on 1 full turn. I was told better to be slightly on the high side then on the low side.
I have heard the question about two different sizes being asked before on the board and have only seen one answer so far, 1 size, no need to stagger the lengths.
Worked for me..... Good Luck!!!
Thanks for the info. I know most use just one lenght. I guess I was more comfortable with the preload being equal on each valve. I guess my question is really coming down to if the torquer V3 has different base circles for intake and exhaust. I guess I will give TSP a call on Monday and find out if I have done this right or not. PS The car runs fine with different lenght PR's. Just has the expected valvetrain noise, not real loud just noticable. I have read on another post about using different lenght PR's as well. I guess its just personal taste. 
Troy
Troy
I have seen a number of guys use two different length pushrods. Can't answer the question on the cam, but I seem to remember someone saying the lobes are different. If you have the cam card, you may be able to check Comp's web site for the lobe data.
The reason I ask is that (if you're using ls7 lifters) is to mention that the stock style lifters have a very generous range for acceptable preload, as it's somewhere around .050-.080 (give or take). Even with the different lobes for intake/exhaust, you may be within the acceptable preload range for both the intake/exhaust with one given pushrod length.
^If this is accurate information, then your varying measurments would make sense. If you used 7.4 or 7.375 pushrod on all valves, what would this make your preload for intake/exhaust for each length?
The reason I ask is that (if you're using ls7 lifters) is to mention that the stock style lifters have a very generous range for acceptable preload, as it's somewhere around .050-.080 (give or take). Even with the different lobes for intake/exhaust, you may be within the acceptable preload range for both the intake/exhaust with one given pushrod length.
The reason I ask is that (if you're using ls7 lifters) is to mention that the stock style lifters have a very generous range for acceptable preload, as it's somewhere around .050-.080 (give or take). Even with the different lobes for intake/exhaust, you may be within the acceptable preload range for both the intake/exhaust with one given pushrod length.
