Ohlin RT guys: front wheel/tire sizes/offsets

[Thoglan]

Apparently Ohlins is one of the few that offers such a “feature”.

I actually thought it was a good feature, means you can dial in your bump/droop without effecting the ride height which is super cool. My biggest complaint is that the same adjustment doesn't exist on the front shocks since your ride height is essentially determined by the bump/droop travel because the overall travel is so low. Would have made even more sense to have an adjustable shock body there but they chose not to for some reason.

[LSB4Me]

My bad, I assumed that collar/threads were there for people wanting to go with true rear coilover!

So somebody just adjusted it too short for you then Max?

All good man! I was surprised to learn about the rear shock length adjustment myself. Apparently Ohlins is one of the few that offers such a “feature”.

My rears were either lengthened out of the box or left at stock length. I can’t be sure which. I do know that my droop was excessive and that shortening the rears 10mm gave me more stroke in the rear—counterintuitive, I know—thereby giving the rear shock a chance to actually dampen impacts. At stock (or elongated) length, my rear shocks were overly compressed at rest and never stood a chance.

[Tbonem3]

My bad, I assumed that collar/threads were there for people wanting to go with true rear coilover!

So somebody just adjusted it too short for you then Max?

[LSB4Me]

I was at 13” before the adjustment last week and am still at 13”, though I might go up as you suggest, Tyler. I do have subframe plates.

As others have said, the rear shock is independently adjustable for droop … and apparently available dampening stroke. Ohlins doesn’t say much about how/when to make this adjustment (my gripe above), but they were quick to suggest it over the phone and were dead on.

Attachment shows the adjustable collar on the rear shock and the lack of clarity about when to adjust, unless that’s just obvious for shops that understand droop adjustments.

[Obioban]

Front tire clearance is a huge PITA with the Ohlins. I ended up using a front beehive spring that was short enough that I could get the spring perch above the front tire (along with camber plates that moved the upper spring point as high as possible), which allowed me to run normal wheel/tire offsets with large tires (and not have to compromise my car with huge amounts of camber). It took a ton of trial and error to get it dialed in, and ended up clearing by 1-2mm.


I think the Ohlins are one of the best setups for this car once you get them working, but getting them working up front (with track sized tires and not stupid camber) is a HUGE PITA compared to... anything else I've run. Really, you should go in knowing that a 245 is the biggest tires you'll run up front (fine for cars that don't see track use) or that you're in for a fight... or offset/camber compromises.

[repoman89]

There is definitely an adjustment to the shocks too. They have a threaded insert and locking ring to set the length. Easy to see in pics: https://www.ohlins.com/product/road-...2001-2005-e46/

[Obioban]

Never heard of adjusting the height or droop or a rear damper for this car, at least not off the shelf stups. How do you adjust the length of the rear shock? AFAIK, you can adjust rebound and/or comp, and you can adjust the ride height with the spring perch. Then you bolt in the stock. Please describe or show a pic/video!

I think stock rear is at 14" and most go to 13" which is a 25mm drop. If you go to 13.2" that's a 20mm drop as they suggest, assuming 14" even is stock rear (I think front was 14.5")

I also don't understand the "all droop, no bump" unless he was just exaggerating. All droop is where the car is up in the air and the wheel is hanging down as far as the shock will let it. That'd be like a 18" rear ride height lol. I'm just not understanding.

The Ohlins' rear shock is adjustable length, so you can set ride height and bump/droop independently. The shock body itself is threaded, it screws into the bottom yellow part, and there's a locking collar:



It's pretty great, actually. Lets you dial in front ride height to optimize for bump/droop, and set rear ride height by optimizing for rake, then setting rear bump/droop from there.

[Tbonem3]

You're running 13" in the rear NOW, so before you were almost down to 12.5"? Yes, that was your problem. I think the confusion has been you referring to the shocks, but it's not the shocks, it's the springs on their perches that are adjusted up and down for ride height. Ohlins or whoever telling you about the shocks' range weren't quite telling the truth (or whole truth) - it's not the shocks, it's your roll center/susp geometry that's the issue being too low.

I doubt there's any adjustment to the dampers themselves besides the rebound (and consequential comp).

If you have subframe plates, and don't have the corrective CMP bushings, you should probably go up to 13.125" to compensate for the lowered subframe.

[LSB4Me]

I had my shop shorten the rear shocks by 10mm. They said a few mm shorter would have been problematic.

I am happy to report that I immediately noticed more travel in the rear. Playing with settings now to finalize the setup, but it’s pretty clear that I was running into the bump stops on any/every road undulation. FWIW, I am running 13” rear ride height with 275/35/18 PS4S and 35psi.

[Tbonem3]

My Ohlins setup out of the box is currently 13" in the rear with 19s as another data point.

Just for more perspective, where did you put the rear spring adjuster at? All the way down, somewhere in the middle, all the way up?

[Epsilon]

My Ohlins setup out of the box is currently 13" in the rear with 19s as another data point.

[Tbonem3]

What are you at now? 13" is lower than what Ohlins told you is bump stop territory, yet the car drives like a "dream" which is why I always take a grain of salt with anything anyone says. I'll assume that car in the shop doesn't have 3mm thick racp/subframe plates that lower the subframe, or has the cmp corrective bushings.

[LSB4Me]

The sensation I’m getting from the rear is that I have no “up” travel. As if the rear shock is choked up to the point of not being able to dampen correctly—or at all, in my case. The Ohlins instructions talk about adjusting the rear shock length, but they don’t do a good job of explaining when/why, imo. The conversation yesterday put it into perspective. Apparently, this is an Ohlins feature. We’ll see what happens when I shorten the shock, thereby taking the shock out of its near-full compression at rest and giving the shock a chance to help absorb impacts.

Ohlins said they have a shop car running 13” ride height in the rear. That’s my ride height. They said their car rides like a dream.

By “all droop; no bump”, he was referring to the movement available to the shock. It can only release down, but any up travel runs me into the bump stop.

If the rear stock height is 14”, I will only shorten the shock 10mm.

[Tbonem3]

Never heard of adjusting the height or droop or a rear damper for this car, at least not off the shelf stups. How do you adjust the length of the rear shock? AFAIK, you can adjust rebound and/or comp, and you can adjust the ride height with the spring perch. Then you bolt in the stock. Please describe or show a pic/video!

I think stock rear is at 14" and most go to 13" which is a 25mm drop. If you go to 13.2" that's a 20mm drop as they suggest, assuming 14" even is stock rear (I think front was 14.5")

I also don't understand the "all droop, no bump" unless he was just exaggerating. All droop is where the car is up in the air and the wheel is hanging down as far as the shock will let it. That'd be like a 18" rear ride height lol. I'm just not understanding.

[LSB4Me]

I was told—by Ohlins—that the rear shock length is set for a 20mm drop. Going lower than that, they said, necessitates shortening the shock to maintain shock stroke and keep the rears off the bump stops.

As I began to describe my driving dynamics, the guy (Brian) at Ohlins cut me off as he knew what was going on. In his words, I have all droop; no bump. This makes complete sense to me. I will report back.

Anyone know the stock rear ride height?