View Full Version : Comp 988 dual valve springs = lifter noise???

12-28-2011, 06:20 PM
Has anybody running the Comp 988 dual valve springs notice any extra lifter noise? I'm noticing enough noise to be annoyed. I'm running the Comp 410 cam and I understand the dual springs were not required but were recommended for my 4.0L OHV aplication. The additional seat pressure has me concerned that the lifters (Brand new Hylift-Johnson) won't be able to keep up. I'll give them a few miles to work any air out before I do anything but was interested in anybody elses experience.

What are your thoughts?

12-28-2011, 07:10 PM
Here is some more infor that I dug up

Sealed Power VS1630 (I think these are factory replacements - can anyone verify factory spring specs)
Closed force @ 1.5" = 98lbs
Open force @ 1.15" = 177lbs
This equates to 225lbs/inch

Comp 988 dual valve springs
Closed force @ 1.6" = 117lbs
Open force @ 1.1" = 232lbs
This equates to 230lbs/inch

So basically there is little difference with respect to what the lifters would have to overcome between the factory springs and the Comp 988 springs.