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What should I set my comp beehive 26918 springs at ..
I'm running stock aluminum 374 heads with a crane 227
Cam and 1.6 rockers....
Comp recommends 1.800 installed height @125#s at the seat
Crane recommends 130#s at the seat
Now the springs are at 1.740 installed height
Suggestions???
 

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"Many" aftermarket springs are spec for 1.80" "installed height". Stock LT1 is 1.70-1.75". Setting up the 918's slightly tighter will increase their seat pressure. In your case the lower height of 1.740" should get you 130+....you would have to do the math

Typically to get a spring at 1.800" installed height you need to have the spring pockets machined down some.

If running 1:6 RR with the 227, check for coil bind on the exhaust side. You should be fine even with a slightly shorter installed height of the 918's, but check
 

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What should I set my comp beehive 26918 springs at ..
I'm running stock aluminum 374 heads with a crane 227
Cam and 1.6 rockers....
Comp recommends 1.800 installed height @125#s at the seat
Crane recommends 130#s at the seat
Now the springs are at 1.740 installed height
Suggestions???
I set Spring Pressure to the minimum recommended for that Cam.
Especially for the Street. Full time Racing is another issue.
Also take into consideration the weights of the Valve/Retainer/Spring condition of the Valve Guides, Push Rods and quality of Valve Seals.

If you have a Spring and Damper. Dampers add 10# Seat Pressure.
Very effective in reducing Valve Trane Harmonics.
Behaving like a much heavier Single Spring at high RPMs.
Behives Springs have a built in Dampener because the Winding Diameter Decreases and the Retainer is very light.

Most Street/Competition cams are done by 6500rpm. Extra Spring pressure is not needed.
Spinning a 350 to 7200rpm reliability requires a bit of thinking.
Competition cams are another Animal controlling Flex, Harmonics, and Mass.

If you have them at 1.74 inch Install Height you added a .060 Shim.
I estimate you now have about 155#/160# Seat Pressure.
Add the Damper an that is at 165#/170#.
Nothing wrong with that if you have Screw in Studs.
If your Cam does not need the extra Seat Pressure go back to 125#/130# Specs.

In Stock we set Retainer height with as little as .020 Tolerance from Coil Bind.
Most of our cams have very low lift but huge Duration to control the Mass.
High Lift Super Stock and Modified cams are a nightmare.
Springs on many of these cars have to be replaced after 50 runs.

Hope this helps.

D
 
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