I finally got around to buying a valve spring tester and testing some lowish mile ap1 valve springs... I have never seen this info posted so I figured i'd share my results

I found 55lbs on the seat for the intake and exhaust.

I'm looking for some high mile springs and some later ap2 springs to test.

Coincidentally these springs have the same seat pressure as a couple different sets of k20 springs I have laying around.

 

Would you be interested in some 100K mile AP1 springs? I should have a few in about 2 weeks. Thanks for the info also.

 

yeah, i'd be interested in those to test.. just one intake and one exhaust spring would do

 

Might as well get/test a couple so you can compare for variance.

 

haha nice! now this is a topic i wouldnt mind reading about in my "probability and statistics for engineers" course!!!

given the data of ap1 and ap2 intake and exhaust valve springs what is the probability that an ap1 valve spring will require 55lbs of force to compress it after 100k miles lolol !!

very interesting topic OP !! kudos

 

Wadzii, do you know what the stock numbers are for these springs? I.e. how much have they deteriorated in performance over time?