C-AEA526 Spring height
Turbo Mini Forums

Hi all,
I am in process of building my stage 3 head with the above springs.
Test fitted the springs and I am getting 36.3mm for exhaust and 36.8mm for intake.
What is the correct height for these springs ?
I will be using Re13 cam with 1.3 rockers maybe 1.5 in the future.
Thanks in advance
John

Are you talking about the installed height? Or are you measuring them Un compressed?

The installed height doesn't greatly matter as they should have a fairly linier rate as they are compressed. You just need to check they are not binding at full lift.

If you want to measure the rate of the spring or the 'stiffness' then you need to measure the force needed to compress them to a given height height and calculate from that.

Installed height is about 35.6mm as you get 75lb seat pressure. You will need to use different height shims to get the required installed height.

This will give you 172lb at full lift with 1.3 rockers. 188lb with 1.5's. About right according to K Calver.

Edited by alaskanow0 on 7th May, 2015.

Class C 3rd Place Avon 2011 14.18 @101mph

Thanks for the answers Slater and Alaskanow0. That's exactly what I am looking for. Off to the shops to get shims.