Aarons NEW Coilover DIY, B3/CQ stuff.

[my2000apb]

I picked up a setup for my B3, somone else has already done all the work. The problem is, they are coming with springs suited to a track/drag car. 700/800 spring rate. What would be a good spring rate for a daily driven 80q? Don't get me wrong, I don't mind a firm ride, but would like to keep the teeth I have left in my mouth...

id say 350 all around

[All_Euro]

More rate in the back helps turn in response and will allow your car settle (front to back) over bumps at the same time... not sure what the right combo for the 80 is though.

[DE80q]

I have read on other's projects all kinds of different combo's used. It looks like the 2B kit uses 350 on all 4 corners as Tim mentioned. I remember seeing somewhere on MG that someone was useing F380/R400. I dont have the equipment to measure corner weights, so cant really go through and do the measurements.

I was thining F350/R375 should be quite liveable and handle well, with the 10vt and all the heavy pieces attached to it up front.

thought?

[Colin2750]

I'm 400 front 450 rear, KW v1s, front swaybar on front and rear with a rear strut bar and a torsen rear diff. Handles like a champ. Will come out on me if hard on the brakes, could slide it nicely with more power and/or wet surface.

Basically what I'm saying is DO STIFFER IN THE REAR. I used to have 360 in the rear and it was understeer city.

[pilihp2]

Stiffer in rear. Do it. Never do stiffer in front, unless you want a boring ride.

[scubagli]

Does anyone know what effect turning the steering arms in will have on a street car? The first set of coils I built I have to run 20mm spacers to get a stock wheel to fit on the 4k...


Old and grumpy.

Anyone? It seems like it would make a really big difference on the outer wheel.


Old and grumpy.

[DE80q]

From reading over this thread, and its sister over on MG, seems that a lot of people are having a problem with the springs rubbing the strut nuts. The setup I snagged is no different. Is there any reason that we are stuck using the 2.5" ID spings, and cant go up to a slightly larger in diameter spring? Would there be somthing in the way?

[Colin2750]

From reading over this thread, and its sister over on MG, seems that a lot of people are having a problem with the springs rubbing the strut nuts. The setup I snagged is no different. Is there any reason that we are stuck using the 2.5" ID spings, and cant go up to a slightly larger in diameter spring? Would there be somthing in the way?

I don't see why not, the stock spring is much bigger.

[speeding-g60]

the kicker there is you need the appropriate sized lower perch for the right sized sleeves. i dunno if there is one. but to use a larger spring the perch needs to be correct.

someone else can do the footwork on that, my springs dont rub my nuts, i dont know what you guys are doing wrong.

and if mine did rub my nuts, i would take that little edge on the strut nut down with a grinder and call it good. its just a casting flash anyhow.

[mr_aj_johnson]

Personally I'd go with 300-350 range and send some HD's back to bilstein for a revalve. $70 per tube, their motorsports guys might have some good info on valve rates. Koni's would be just fine as well.

[SEStone]

My adjusters are seized so I'm going to be replacing them soon. I went with the A1 Racing parts here, including the set screws to lock the collars in place. The set screws seem to have damaged the sleeve threads, so all the adjusters are basically immobile.

To prevent this, I'd like to go with a lock/jam nut type of setup next time. These A1 parts are the only ones I've found with these big blocky threads, so I was thinking of just buying two perches per corner and running the second upside down to jam against the real spring perch. I have enough adjustment range that I think the extra thickness will not be a problem.

Thoughts?

Sam

[speeding-g60]

that seems to be the way many companies do it.

[pilihp2]

The set screws on mine damaged my threads as well as seized and stripped on the fronts. I had to drill mine out. What a bitch.
Definitely like your idea Sam.

[ringbearer]

I agree with this idea. My Koni sleeve and perch set came with nylon tipped set screws but the jam nut solution is better in the long run.

[Wheeljack]

Agree that the A1 set screw is a poor design for these. I used a few dabs of silicone to keep mine in place, but that only works because I tend to 'set it and forget it' for my uses.

The other option is like Ground Control which uses a split ring design which can be clamped with a screw. Even with these, care must be taken to keep the screw from seizing over time, but still better than the set screw design.

I think I like the jam nut approach best though. It would be nice to have a better option than running two perches back to back though. The threads are probably ACME and some other manufacturers may have compatible parts, or possibly a full setup alternative to the A1 stuff.

[Zaworek]

Im finally back on working on my coupes after a longer break and instantly runned in into little problem and wanted to ask for some wisdom from You guys. I have the coupe uprights and bought the sleeves from a1 and they dont fit on my up rights. They are tiny bit smaller. The question is should i look for another sleeves or maybe i could use urs4/6 up rights and built the coilover using them for the coupe. The coupe will get wide body later and i think using the urs4/6 up rights F/R would make it easier with custom lower control arms to offset the diffrence. Please let me know your opinion.

[DE80q]

To get the sleeves to fit you will need to grind down the housing some. I have done this on many uprights with no ill effects.

As for the UrS uprights, I have no idea.

[speeding-g60]

take the paint off the housings.....

[A1QSHIP]

Does anyone know what effect turning the steering arms in will have on a street car? The first set of coils I built I have to run 20mm spacers to get a stock wheel to fit on the 4k...
Old and grumpy.

Turning the steering arms inward or outward will affect what is known as the Ackerman Angle. Even raising or lowering the arm can have an effect on Ackerman Angle. Essentially, this is the angle that the wheels take when a vehicle is in a turn. Here is a youtube video that gives a basic understanding of Ackerman Angle. This guy has other useful videos posted as well.
https://www.youtube.com/watch?v=oYMMdjbmQXc
There are other videos that are linked to the above that give more information but the above is a good start.

If you are really studious I can recommend a book titled "Race Car Vehicle Dynamics", by Bill & Doug Milliken.
http://www.millikenresearch.com/rcvd.html
Ackerman Angle takes in to account vehicle wheelbase, steering rack position & type, steering link length, steering arm length & angle inwards/outwards from the centerline of the vehicle. Also considered is the range of motion that the steering arm takes as the suspension moves thru its range of travel.
I used the information in "Race Car Vehicle Dynamics & took measurements to determine on a C4 chassis that the Audi engineers knew what they were doing when they set position of the steering rack & the angle for the steering arms on my UrS6. It was very close to what the Milliken's thought was ideal for a street vehicle.

On a vehicle meant for a road race course or if you are trying to improve a situation involving front tires scrubbing in a turn there may be benefits to moving the steering arm position.
For a drag car keeping the front wheel toe measurement close to zero as the front of the vehicle moves upwards & downwards would be the ideal. I helped a friend align his drag car (Nova) & then had him take pictures of the car as it moved down the track. We then realigned his car with the front of the vehicle raised to where it trended to be during the course of a run.
HTH, Chris

[speeding-g60]

For a drag car keeping the front wheel toe measurement close to zero as the front of the vehicle moves upwards & downwards would be the ideal. I helped a friend align his drag car (Nova) & then had him take pictures of the car as it moved down the track. We then realigned his car with the front of the vehicle raised to where it trended to be during the course of a run.
HTH, Chris

this, is how i have my awd drag car aligned. me in it, and ~1" lifted in front to simulate how it actually drives down the track.

[A1QSHIP]

FWIW, Messaged Albert @ AKmotorsport about the steering arm position on KW suspension front struts for the B3/B4 chassis. He replied that the dimensions were the same as stock. Without having the front struts side by side.....

[pilihp2]

FWIW, Messaged Albert @ AKmotorsport about the steering arm position on KW suspension front struts for the B3/B4 chassis. He replied that the dimensions were the same as stock. Without having the front struts side by side.....

Albert makes some cool stuff, but he isn't super helpful when you have questions....

[Zaworek]

The sleeves won't pass the treaded area on the housings. Would have to take bit there which I don't think is good idea will post pictures when I get home.

Also I see you guys talk about kw's
Cam I still get a set for the coupe in US ?

take the paint off the housings.....

[DE80q]

The sleeves should easily pass the threads. Check to see what the inside of the sleeve measures. It should be right around 2.170" iirc.

[Zaworek]

Will check and post my results

The sleeves should easily pass the threads. Check to see what the inside of the sleeve measures. It should be right around 2.170" iirc.