Did something change with the 3850 roller springs? Im pretty sure when I ordered my valvetrain kit from my local PBM dealer in his flyer it was printed these springs were good to max lift of .720". Now when I look at these springs for replacement the website shows max lift of .650". Did something change, is it a typo or am I over stressing my springs on my engine by running a .680 lift cam with them?
cgarb wrote:Did something change with the 3850 roller springs? Im pretty sure when I ordered my valvetrain kit from my local PBM dealer in his flyer it was printed these springs were good to max lift of .720". Now when I look at these springs for replacement the website shows max lift of .650". Did something change, is it a typo or am I over stressing my springs on my engine by running a .680 lift cam with them?
I say it's a typo. I just set up a set this AM.
255@1.910
635@1.250
670@1.200
1.150 CB
Last edited by user-9274568 on Tue Apr 26, 2016 1:25 pm, edited 1 time in total.
cgarb wrote:Chad, typically how many passes are your customers getting out of a set of 3850 springs before they are no longer within spec?
Depends really. The John Force burnout guys, one season. I had a set of 3850's back not long ago with 2 seasons on them. Best guess around 250 passes. Most are Erson cam equipped engines as well. I use this spring and a 3860 as a standard spring, then option from there.
The seat pressure is always good, open pressure goes away.
Is valvetrain heat the main issue with the open pressure going away, rpm related or is it just the material they are manufactured from. Would extra oil to cool the springs help that somewhat?
cgarb wrote:Is valvetrain heat the main issue with the open pressure going away, rpm related or is it just the material they are manufactured from. Would extra oil to cool the springs help that somewhat?
Maybe. I've seen it with all springs. I even did a KMotion K1000H test with a customer.
Im sorry but I will use the pbm valves and retainers, but the springs coming from pbm/epw are not high on my list at all. Being the highest stressed part on a roller cam race engine I don't think its worth the risk to have them drop psi early in there life. I have tested new ones and they were soft on the specs. I will stick with manley or isky.
PS: The last custom roller cam I received was extremely nice.
Eric found the core I needed to fit the grind with the cast dist gear I wanted.
10 business day’s to my door with a “Cam Pro” report. Thank You!
Eric is with Howards Cams.
I have used a few Erson cams in the past. Always perform as expected!
cspeier wrote:There are several Erson springs that are the same as Manley. just saying...
No way...they are all made in separate little factories inside one big factory...just like left twix and right twix. Same part but completely different once they get placed in their respective packaging.
