Amro

Ok, I went back through the archives and have learned a bit. Now, I have a few questions that I don't think have been hashed out.

1. Koni basically has 3 different types of shocks. The one setup for Audi appears to be a twin tube hydraulic. From what I understand, hydraulic shocks only control rebound and not compression. Basically compression control is left to the spring. Do I understand this correctly?

2. Looking through their PDF file, I see on their coil over "threaded suspension kit" they recommend the kits be installed with bump rubbers. Is this already part of the A4 or is this separate?

3. The kit part number for my A4 2.8q looks to be 1150-5019. The individual shock or strut part numbers appear to be 82-2427(f) and 8210-1162(r). Do these parts, along with the progressive rate springs, define the coil over kit?

4. Their notes state the fronts are ride height adjustable. The rears are ride height adjustable and "externally adjustable". What does externally adjustable mean?

5. What are the spring rates?

Hopefully all you guys "burned out" on answering the same questions over and over will have something new to answer.

Thanks for any help,
Amro

Chip G

All shocks (as far as I'm aware - or at least all relevant shocks to this discussion) will damp oscillation in both the compression and rebound direction. Springs do not 'damp' compression. A shockless spring will oscillate until the energy put into it is damped by friction - this is the role of the shocks. Where compression and rebound come into play is this - low level shocks are non-adjustable and have set levels of compression and rebound damping (which are frequently different). Simple adjustable shocks allow you to adjust the damping in one direction, or in both directions simultaneously. Double adjustable shocks allow you to adjust damping independently in compression and rebound. This is good because say for instance you stiffen your springs. You now want MORE rebound damping (since the spring is trying harder to extend) and LESS compression damping (which effectively adds spring rate and stiffens your ride). Hope this makes some sense....

BTCC A4

Ive got a group buy on em! Email me at oettinger@kittymail.com

eharleq

All shocks are hydraulic.

Compression dampning varies dramatically from model to model. They have charts to help. Linear is stiff, digressive is better, the Audi sports have a mild blowoff (pressure bypass) for very sharp bumps.

I use celasto bumpstops from Ground Control.

Shock-NOT strut. Kit is spring and shock. Don't have the numbers handy.

External adj. is a manual valve on the outside. Vastly better than the take off and twist the shaft of the standards.

Spring rates are a bunch of lies as far as I have found. Only way is a coil tester.

Audiboy

I have tried to stand on my springs and measure the compressed height after but I keep falling off ;P

zain

But nobody could tell me mine. I've heard anything from 400 to 600 lbs...

Audiboy

by measuring the compressed height and knowing the corner weight - or at least the average of one side, because each corner affects the other.

Just to give you an idea, if you have 500lb/in springs, and the front of the A4 weighs 2000lbs, then I expect your springs to be 2 inches taller when taken off the car. If they are any longer, then your spring rate is much lower.

The Koni and progressive designed coils are trickier, that they have to be measured as like two separate coils. Either way, if I had only measured my coil height before I installed it, I would now by now my spring rate. I think I have 300/350 but I couldn't read the German spec sheet so the units I have used are probably all whacked up. One of these days, I'll have to adjust the rebound again so I'll measure - or stand on my spring again and see if I don't fall off this time ;P

zain

have somebody measure the travel. Set damping this way too I suppose...

Audiboy

All I have to do now is measure the empty ride height and with me in it (or GF with a bunch of sacks of rice) to see how much it lowers and get the spring rate from there. Thanks he he