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#1
06-16-2009, 09:01 PM
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Valve springs. Yes/no or suggestions.
Going to run a HR with SR lifters. Heads have been cut and installed ht is now at 1.7"
Found a set of springs. 1.8 installed, 125lb seat, 1.1 coil bind, 438lb per inch. Thought. Install @ 1.750= 147lb on the seat. Lift is .540"= 383lb open. this leaves .110 from coil bind. Good/bad or is there a roughly stock diameter spring that is better than what I have come up with? I have already bought/replaced more parts than I care to on this project.
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72 GTO 400-M20 Lucy Blue 86 2+2 Black 09 G8 GT red 08 Torrent GXP (wife's) 09 G8 ST (UTE) black A pissed off fat house chimp on dope would be a lot more deadly. |
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#2
06-17-2009, 06:01 AM
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Spring specs are stated with out the inner step of the retainer factored in, so if the box states 147lbs at 1.750" your installed height of 1.700", or plus .050" will add 22lbs if the spring rate is 438lbs per inch.
If you than add in the 1/8" inner step ( and I am guessing at around 1/8") of the retainer which will add in another 40 or so pounds, you will end up with 200 or so pounds of seat pressure. This will be ok for 6500 rpm with the lobes of a HR roller.
__________________
Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
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#3
06-17-2009, 06:02 AM
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Sorry , that should have said minus .050" not plus.
__________________
Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
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#4
06-17-2009, 09:23 AM
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Gotta ask. Why are you going to use a HR cam with solid lifters? Not challenging, seeking "rationale". I know of several doing it, but am curioius why you chose that "path".
Depending on the grind, seat pressure for a solid roller must be at least 160-180 lbs. 125 is DEFINITELY not enough. If you're using Comp XE lobes, 160 will suffice. If not, closer to 200 is probably better. Make sure, if a street-driven engine, you use a lifter with POSITIVE oiling to the wheel. Crower calls their's "HIPPO" (high pressure pin oiling) and Comp calls their's "Endurex". Either are excellent for street use. Jim |
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#5
06-17-2009, 09:31 AM
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X 2 on the spring pressure.
hyd roller lifters with 147/383 is Ok if in the 235@.050 plus range. You can run as close as .050 coil bind without long term issues. |
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#6
06-17-2009, 01:00 PM
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Quote:
-For performance? -For durability?
__________________
Matt 70 GTO 400 4-speed "Turbos make no noise and leave the line like Baby Diarrhea!" - GTOGeorge |
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#7
06-17-2009, 05:48 PM
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Quote:
I will want to check them carefully for that As I do remember a young lad that got these almost new valves from a set of heads and put them into his 48's back in the early 70's..... The intake is an extreme lobe 242 @ .050 164 @ .200. The exhaust is a marine lobe 250 @.050 and 166 @.200 LS is 112 with 540/541 Lift. Lobes are #'s 3317 and 3377
__________________
72 GTO 400-M20 Lucy Blue 86 2+2 Black 09 G8 GT red 08 Torrent GXP (wife's) 09 G8 ST (UTE) black A pissed off fat house chimp on dope would be a lot more deadly. |
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