wanna911

Discuss........ Is it possible to do both?

95m3racer

They have different purposes.

It depends on many variables. For most Porsche applications, I'd suggest a tender to support the amount of droop travel they are normally setup and designed to have.

Helper springs pretty much don't have any use on track/racecars.

wanna911

I thought the helpers were for the droop, to keep the springs seated.......

Also what makes the springs un-seat? Jacking? Jumping gators etc? Is it easy for them to unseat?

Van

On my car, putting it on the lift will cause the front springs to un-seat. Never happens at the track, because I only jack up 1 side at a time - the sway bar puts enough pressure on everything to keep the spring in place.

wanna911

I've seen some pictures of helpers on some WTCC cars and I have some friends who run helpers on track cars. Trying to figure out which ones to get, sounds like tenders may complicate the build a bit and make the car variable spring rate, but would alleviate the need for helpers.

Geoffrey

The springs unseat because the damper "droop" has not been set correctly for your spring package, or you've not selected springs that will work within the damper travel.

I've not really seen helper springs on a well set up car, and am not sure why you need them if you've used the correct springs and set the droop correctly.

The tender springs are used to change the spring rate of the suspension during the initial compression of the damper. They should be collapsed when the vehicle is at rest and I use springs that are proprotional to the weight distribution of the vehicle, so in a 911, the rear tender springs have a higher spring rate than the front. I generally have to change the droop limiters in the dampers for the individual car I'm working with.

Spartan

I always thought if its a truely track only car then they are not needed. If its a hybrid (ie track and street) then they are needed as is a higher possiblilty of the suspension coming unloaded. You never know when your going to go ferris bueller on the way to the grocery store and need the tender/helper springs

Potomac-Greg

I got tenders because I got tired of explaining to people that it was "OK" to have the suspension make a huge CLANG when pulling into a driveway at an angle. I also worried that I was beating up on the upper spring perch.

Van

Let's get our terminology correct...

Helper spring: a very light compression spring to keep the main spring against the perch at full droop - is fully compressed under normal circumstances




Tender spring: a secondary spring that provides a secondary spring rate until the spring is fully compressed or it's travel is limited by a hard stop




This second pic is from a very comprehensive website on shocks: http://www.pirate4x4.com/tech/billav...lovers/Part_1/

wanna911

From what I've been able to gather the Tender springs can serve as a helper spring keeping the main spring seated under droop as well as contribute to a variable spring rate. Helpers don't have enough rate to do anything but keep the main spring seated, same is not true for the Tender.

Seems like you want to keep the spring seated, but do you want variable spring rate option with the tender at 150-200lbs or not? In the case that you don't you get the Helpers springs.

Gasser

Well, Chris Cervelli put them on my Race car...

Paddy

Hey Gasser, what spring setup are you running, main and tender spring rates?

Thanks, Patrick

Van

FYI, in a dual rate scenario, calculating spring rates is different:

Combined Spring Rate

This is used when two springs are stacked on top of each other.

Combined Spring Rate =
(Spring Rate 'A' x Spring rate 'B')
÷ (Spring Rate 'A'+Spring Rate 'B')

For example if the rate for spring 'A' is 200 and the rate for spring 'B' is 500, the combined rate is calculated as follows:

Combined Spring Rate =
(200x500) ÷ (200+500) = 143

(Source - Hyper Coil: http://www.hypercoils.com/TechTips/?TipNO=10 )

IPguy

Which "them", tenders or helpers, as you can see from other posts, they are very different.

wanna911

Doesn't seem like there is much open knowledge on the necessity of these units. I know that a lot of race cars have tenders, and many have helpers, sometimes it's hard to tell which is which, but from the conversations I've had, I know people are running both.

The question is WHY one vs the other, or what is the penalty for running neither other than noises?