Question about shortened strut housings.

[2002maniac]

When you shorten the strut do you have to cut threads inside the tube for the strut collar nut? I'm not planning on this mod, just curious.

[1991 318is]

Not a clue.

But I was wondering why there are no responses. Apparently it's not a stupid question or someone would have jumped on the opportunity to call you a dumbass. Maybe 22 people viewed your post and don't know the answer. I personally haven't seen a tap or die that big. The strut is secured in the cast spindle/caliper bracket . It could be disassembled, shortened, and reassembled in the same manner. Probably with heat and/or special tools. Some vendors offer shortened struts. The answer to how it's done may be you buy them.

[redcarbon]

what I have gathered is that yes, you chop off the threads of the housing, then chop off as much as you want to take out and then weld the section with the threads back on so that you can secure the insert with the top nut thingy.

This does not seem trivial because it would be hard to get that part on parallel again without some mitreing or two clean chops. but what do I know, I've never done it.

[Beej '86 325es]

What they do is take a 4" section out of the middle and weld it back together.

[StereoInstaller1]

I was just wondering what would be done to make sure there was enough threaded material left to seat the top nut properly.

Any real industrial tool supply would have that size tap or die, but I bet they would be $100 each. I wanted to buy one for bicycle sizes, the bottom bracket one was like $150.

Why would they remove 4"? Seems like your strut cartridge would have to be really tiny then...is this a "Track Only" thing?

I have only done the drop on mine, but then Jordan did just about all of the work, but the principal is the same (or nearly so) on any strut.

Luke

[Beej '86 325es]

Yeah, they use a shorter strut, I believe it's actually from a certain model of VW Corrado. From what I understand it's supposed to put the shock in a more useable range. Probably more intended for track vehicles. I'm going to do this to my car (whenever I get the other strut pulled), which I'm turning into a street toy / autocrosser / occasional track day. As an added bonus, that's 4" less you have to jack up your car to get the tires off the ground. :)

[rwh11385]

shortened = tits mod on the track. there's no real other reason to do it. you may be fast with regular sized konis, but if you are competiting (in actual race) with someone in an identical car but with short konis, they will be faster.

and e36s, there are just manufactured shortened housings. bolt on.

[StereoInstaller1]

shortened = tits mod on the track. there's no real other reason to do it. you may be fast with regular sized konis, but if you are competiting (in actual race) with someone in an identical car but with short konis, they will be faster.

Let me guess...lighter weight make you faster?

JK
Luke

[boom-monkey]

Let me guess...lighter weight make you faster?

JK
Luke

Feel free to correct, but I'm fairly positive is because it gives you more usable suspension travel, making you less likely to hit bumpstops.

While we're on the topic, anyone know of a shock with a shorter housing to be used for the rear? My Bilsteins really only have about 2" when my car is sitting level.

[rwh11385]

Let me guess...lighter weight make you faster?

JK
Luke

Think of it this way: why would a car with dampers produced to ride with the car lowered 1.5" work well when racing lowered at 3"? and this is why when you slam your car, it'll ride like shit and handle like shit

Robbie is right on. Shortened Konis and housings work better for lowered racing cars.


Konis have shorter tubes for both front and back. What are you on anyway? Am I crazy to put you on Spax? or what?

[boom-monkey]

You correct sir. I'm sitting on Spax with Bilsteins front and rear.

Saving up some money and will probably run shortened strut housings with Konis.

Although as of right now I'm not sure the springs I'll run. Still debating between GC and H&R Race. We shall see.

[Mystikal]

Thought I'd throw in some experience.

With no bumpstops and regular Konis, the E30 strut has enough travel that a stock sized tire can contact the plastic liner up top (although just barely). So with short bumpstops (mine are less than 1"), you're already using most of the physical room in the wheel well. The only advantage I see to shortened housings is the ability to use longer and therefore softer bumpstops, and perhaps the argument of employing a "better" part of the stroke range.

In any case, unless it's competitive racing, it's in no way useful.

[coupeowner]

This does not seem trivial because it would be hard to get that part on parallel again without some mitreing or two clean chops. but what do I know, I've never done it.

Using a bandsaw you can get two even cuts, then use an old strut to line up the two pieces after you have cut the 2" chunk. Get a good welder to put the two pieces together (with the old strut still keeping everything lined up). I would also suggest welding on the M3 swaybar tabs while you have the struts out and a welder on hand.