[Z06] PRC LS7 heads: Pushrod length?
#1
Race Director
Thread Starter
PRC LS7 heads: Pushrod length?
For the few in here that have done the PRC LS7 heads on their LS7, can you comment on what pushrod length you ended up with? Stock is 7.8", I believe, and I have heard 7.750 from a few for the PRCs.
#4
Team Owner
Measure.
I'm running 7.8125" on stock unmilled PRC 285ccs with a comp cam.
If they are milled you will need shorter. If they are unmilled it will probably be close or a bit longer than stock.
I'm running 7.8125" on stock unmilled PRC 285ccs with a comp cam.
If they are milled you will need shorter. If they are unmilled it will probably be close or a bit longer than stock.
#5
Race Director
Thread Starter
I plan to measure(or may have them installed at a shop and they will), but I was just trying to get a feel for the reality of having to wait for custom length pushrods(longer install time) versus being able to bolt on and go. Looks like I need to figure a few extra days to get the right pushrods.
#6
Safety Car
Member Since: Dec 1999
Location: Virginia Beach, VA & Port Charlotte, FL (snowbird)
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I bought the Comp Cams pushrod length checker and measured the required length for my 0.030" milled PRC 265s. I came up with a 7.75" long pushrod requirement. This length provided me with the Katech specified optimum lifter preload, 0.070". The stock length pushrod almost completely compressed the lifter (waaaaay too much preload).
#8
Drifting
When I had WCCH do my heads and milled them .030 I used the comp cams push rod checking tool and with the CHE rockers and the cam lobes set to base circle I got .070 - .080 with the stock push rods....
Mark
#10
Team Owner
#11
I plan to measure(or may have them installed at a shop and they will), but I was just trying to get a feel for the reality of having to wait for custom length pushrods(longer install time) versus being able to bolt on and go. Looks like I need to figure a few extra days to get the right pushrods.
I needed a 7.760" 3/8" .120 3 piece pushrod to get the .060" preload I was aiming for... called at 9 am, got them overnighted and the car was on the dyno the next morning.
#12
Team Owner
Smith Bro's Pushrods offers a next day turnaround on custom length pushrods, as long as you order by 10am PST.
I needed a 7.760" 3/8" .120 3 piece pushrod to get the .060" preload I was aiming for... called at 9 am, got them overnighted and the car was on the dyno the next morning.
I needed a 7.760" 3/8" .120 3 piece pushrod to get the .060" preload I was aiming for... called at 9 am, got them overnighted and the car was on the dyno the next morning.
#14
Race Director
Thread Starter
#16
Team Owner