Bilstein Gpa Coilovers

[evojay71 0]

I'm running GPA Bilstein coilovers,gravel inserts and 185lb springs on my 205 1.9 road rally car but it still feels way to hard on the rough whites we use,just seems to bang alot and no give I don't want to change the set up but is there anything I can try to soften things up a little i.e would helper springs work at all??? Any good advice would be great!!!

[welshpug 1,683]

how low are you running it?

[Craigb 2]

Have you stripped them down recently , I had this with mine a couple of years back . they were full of water . I drilled a small hole in the base of the strut body, now if any water gets in there it is pushed out on the next compression stroke.

 

Also how old are the inserts . I've just replaced mine as i was concerned that they were stiffening up , now the front end feels much better.

 

A final thing to consider is are you running any pre load on the springs , or do they come loose off the pans when on full extension

 

185's are normal for road rally spec , but i am considering trying some longer 170's once i've worked out what i really need

[evojay71 0]

Have you stripped them down recently , I had this with mine a couple of years back . they were full of water . I drilled a small hole in the base of the strut body, now if any water gets in there it is pushed out on the next compression stroke.

 

Also how old are the inserts . I've just replaced mine as i was concerned that they were stiffening up , now the front end feels much better.

 

A final thing to consider is are you running any pre load on the springs , or do they come loose off the pans when on full extension

 

185's are normal for road rally spec , but i am considering trying some longer 170's once i've worked out what i really need

 

I've run them all different heights on different events and really feel no different to me really

I've rebuilt the only one event ago so they're fine,I had another pair of springs and put those on I've said in my thread they were 185s but they could even be 175s??? He did say but can't remember for defo but they didn't seem any softer either.

[SPGTi 2]

I run the same on my road rally car. I have 9" 185lb springs and use helper springs. I find it spot on, and get no crashing or banging.

 

Steve

[philfingers 5]

they really need stipping after every wet event and drying out. 185 is std gravel spec, they should be fine. I've got an Mi in mine and Andy BAker (AB Motorsport) advised 200-300 progressives do to the slight extra weight of the Mi (alloy) over an 8v. Mine were ok, no crashing but need new inserts as it's like a pogo stick at the moment. The rumours that billies last forever is untrue, they're still much better than anything else other than proflex in my opinion

[evojay71 0]

I run the same on my road rally car. I have 9" 185lb springs and use helper springs. I find it spot on, and get no crashing or banging.

 

Steve

 

This may well be worth a try,I've never had anything to do with helper springs,is there any poundage that I should go for or do they come as is???? By the way is there just the one gravel insert availible or are there softer options??? Cheers!

[Rom 0]

Im tempted to get some helper springs for my coilovers too. But didnt know what ones, lb wise.

How does it calculate ? Adds on to spring rate ? or some fancy formula

[evojay71 0]

Im tempted to get some helper springs for my coilovers too. But didnt know what ones, lb wise.

How does it calculate ? Adds on to spring rate ? or some fancy formula

 

I'm confused.com!!! Obviously the helpers will be softer than the springs your running,think I'll have a looksey at my Demon thiefs catalogue for options. I do have a set on my jumbo Proflex I bought off a mate for my Evo,if they'll fit?? But I have no idea of poundage.

[Rom 0]

Mine are Gaz, so are 2.25 inch ones, not sure what billies are. The poundage for helpers is very low iirc, like 25 lb etc. But unsure on length and poundage to try.

 

And tbh, im a little unsure of what they do...and do say help ! Obviously they could take up any slack when the shock is uncompressed, to make sure springs stay seated, but do they have another use.

[alync406 4]

And tbh, im a little unsure of what they do...and do say help ! Obviously they could take up any slack when the shock is uncompressed, to make sure springs stay seated, but do they have another use.

 

As far as i know all the helper springs are for is keeping the springs seated when the shock is uncompressed,that is why they are very low lb rates.

[philfingers 5]

yep basically they are very low rated so are there to take up any slack in the system. You're rate would still be 185 basically as once the car is sat on it's wheels the helps are fully compressed/coil bound. Obviously you need to wind your ride height adjusters down to keep the same ride height

[ifcho 0]

1. Tender Spring - The Tender spring relies on a Main and Tender spring concept that provides a softer initial rate when both springs are compressed together, then delivers the desired firmer ending rate once the Tender spring closes completely. The Main spring determines the final rate of the system. The Tender springs are available in a variety of linear-rate as well as progressive-rate characteristics and determine the initial rate of the system.

Използва се като по-мекичка пружина, в началото на хода на окачването.

 

2. Helper Spring - A Helper spring is used to prevent the main spring from becoming loose in the spring seat when the wheel is at full droop. The Helper spring, unlike the Tender spring, has very little spring rate, and therefore has no effect on the suspension characteristics of the vehicle. Up to 50 mm of spring-to-perch gap can be covered with the use of a Helper spring.

[Rippthrough 98]

No, they don't add to the spring rate, they actually make it softer until the helpers are fully compressed.

 

Say you have 9 inch long, 200lb/inch main springs, and 1 inch long, 40lb/inch helpers, and the helpers will be coil-bound at half an inch.

 

To get the helpers to compress fully, you obviously need 20lb of loading to compress them the half inch.

However, you've also now got 20lb of load on the main springs, so they will compress 1/10th of an inch.

 

So, the initial spring rate for the first 0.6 inches of travel would be 20/0.6 = 33.3lb/inch.

 

After the first 0.6 inches of travel you will then be totally on the main spring at 200lb inch.

You can give yourself a 'progressive' spring rate this way with a longer, stiffer helper, but it results in two different rates rather than a true progressive curve.

Edited May 3, 2009 by Rippthrough