Another roller question

ecmo92

New Member
Joined
Mar 14, 2002
I called hartline and found out what the kit has and it sounds like a good deal. My ? is do you need new springs when going with a roller? Ive been doing some searches and noticed a few saying they were getting them. Is this a must? I dont know if this will help but Ive got around 4k on my new motor before the flat tappet cam failed. So the springs I have arent that old. I just dont want to spend money if I dont have too.:(
 
Springs should always match the cam. The springs the cam manufacturer recommends are ones picked to keep the lifter in contact with the lobe through the intended rpm range of the cam. If springs are stiffer than needed you'll cause extra valve train wear. If springs are to weak the lifter will hammer on and off of the lobe and transmit that through the valve train. You learned one 4k lesson already......Fool me once shame on you, fool me twice shame on me :D

HTH: Jason
 
???????????

Roller cam springs are usually of a higher rate due to the added weight of the lifters...using a spring that is designed for a flat tappet can/will limit the rpm capabilities of the engine due to valve float .
Spring pressures are usually:
flat tappet- lowest.
hyd roller- next highest.
mechanical roller-highest.
Example:
My hyd roller had,[when new], springs that were 130+ seat, and 380# open at .550 lift. After some 20 passes and 10 dyno pulls, the engine refused to rev past 5700. [The original revs were well over 6000] a check of the springs revealed the seat pressure to be 100# and WFO was 300#.
I am now using the CC "beehive" springs. The design is such that the wt of the valve/spring assy is about the same as a standard spring w/ titanium valves. CC states the new springs should allow as much as 1200 more rpm....:D They install at a higher pressure:
Seat is now 170# and open is 400#. These values will drop some once the engine has been run for a few passes.

FWIW, the way the original springs were killed is thot to be hi rpm burnouts.....The driver has been "re-educated"..:eek:

going to the TnT tomorrow.. more later..
 
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