raising trailing arm brackets

[alistairolsen]

One is an adjuster for wheel angle, the other is moving the pickups on the chassis (subframe) and they DO NOT have the same effect.

[JimmyP]

Yeah, that DTM adjuster is awesome. Camber and toe adjustable from one side. I'm already thinking about how I could replicate it. I wonder if it's $230 per side or for both sides?

Unless you are a machinist and have access to the machines and the skills to do it, or a bro hookup with someone who does I doubt you can replicate for less than what they are asking.

Many years ago, I loaned that outboard adjuster assembly out of one of my spare Gruppe A trailing arms to a "friend" who then flaked and lost it, left it behind in a divorce, dog ate his homework, never saw or heard from him again, etc, etc.
End result is I now am now (still) missing an adjuster assembly out of one of my trailing arms.
To get someone to replicate a one off was going to be expensive.

I too am curious if that is for a pair or each, a pair would be a great deal, but even each,,, would still be cheaper than a normal person (who isnt a machinist) could make one.

[hoveringuy]

For anyone that has the 12mm raised subframe, how much clearance does that leave between the trailing arm brackets and the chassis?

[kronus]

For anyone that has the 12mm raised subframe, how much clearance does that leave between the trailing arm brackets and the chassis?

very very little, maybe 2-3mm. subframe may rub on the chassis in the middle, even.

[JimmyP]

very very little, maybe 2-3mm. subframe may rub on the chassis in the middle, even.

Yep, I know more than a few racers who said f - it and cut adjustment windows in the backseat area to access the TA bolts afterwards.
Especially if you still use a stock gas tank (vs a fuel cell), the combination of raised subframe and slotted adjusters can be a real PITA to actually adjust.

[hoveringuy]

Is that with the eccentric bolt where you need a wrench on each side?
The IE ones seem to have the extreme inside and outside sides of brackets self-threaded, so you only need access to the "easy" side of the bolts

My eccentrics are a pain even with stock subframe... Ugh

[1990m3]

Yep, I know more than a few racers who said f - it and cut adjustment windows in the backseat area to access the TA bolts afterwards.
Especially if you still use a stock gas tank (vs a fuel cell), the combination of raised subframe and slotted adjusters can be a real PITA to actually adjust.

I've seen the same thing with the subframe being raised so high people made cutouts in the backseat to adjust.

I think that DTM type adjustment kit looks pretty slick, it's the best setup I can remember seeing that an end user can weld in themselves. Looks promising for end of 2019 upgrades :)

[hoveringuy]

I've got my subframe coming back together for installation in the next week or two. I raised the IE brackets up by 12mm. I'm using IE subframe bushings, but stock rubber TA bushings.


One thing I've realized is that raising the pivot point up by 12mm also increases the lever-arm on the bracket so I've significantly beefed up the strength of the bracket welding. The other factor is that there will be a stronger fore-aft twisting force on the subframe during braking and acceleration which will put more strain on the diff bushing (and the diff cover).

The paint is Eastwood 2k Epoxy from a rattle can. Incredibly tough!

I also noticed that the IE serrated tabs come in two different "flavors". The serration on one kind is slightly offset from where the serration on the other. If my toe won't fall into a good range I could switch tabs. My math says that each notch is about 1/4 degree.

The nut is also welded to the plate, so this will be single-wrench adjustable from the inside. We'll see how that goes...

[AndrewBird]

Unless you are a machinist and have access to the machines and the skills to do it, or a bro hookup with someone who does I doubt you can replicate for less than what they are asking.

This is me. lol

Time to actually work on it is the scarcity for me.

[Massive Lee]

Instead of the slotted TA mounts, you should consider the DTM style adjuster. Can't remember who, but some vendor has it for $200 or so, and adjustment would be so much easier.

The DTM subframe was raised. And so were the trailing arm pick-up points. And those were heavily reinforced. Raising the subframe by 12mm is more than enough to get rid of a lot of camber and toe. Raising it by 9mm is not enough. Must be 12mm. I'd say that if the subframe risers came from Ireland Engineering, then they didn't do their engineering homework.

[E30SPDFRK]

Raising the subframe 12mm gains you exactly the same amount of camber reduction that raising the car 12mm does. AKA not much.

If you want to be able to use the posi-lock adjusters, you can't raise the subframe at all.

[BeirBrennerE30]

The DTM subframe was raised. And so were the trailing arm pick-up points. And those were heavily reinforced. Raising the subframe by 12mm is more than enough to get rid of a lot of camber and toe. Raising it by 9mm is not enough. Must be 12mm. I'd say that if the subframe risers came from Ireland Engineering, then they didn't do their engineering homework.

Lee, I was under the impression that the DTM cars subframe wasn't raised, but the differential was raised up relative to stock, in a attempt to correct CV angles. The outer pick up point for particularly the late DTM trailing arm had a lot of adjustment and was often much higher than stock, and higher than the inner pick up, to lower the roll center. The sweep angle decrease also lowered the roll center/reduced camber and toe change. Raising the entire subframe would have negated some of the benefit of having the roll center adjustment on the outer pickup.

[Massive Lee]

I had an original and unused DTM subframe for a week to take measures. The subframe is indeed raised by 12mm. The bell holding the diff is also different from a stock one.

[LowR3V'in]

Raising the subframe by 12mm is more than enough. Raising it by 9mm is not enough.

is 10 enough or is it 11?

[LowR3V'in]

hey so just to get this straight.

raising the subframe 12mm will do the same thing as raising the car 12mm?
period. nothing else?

Does raising the subframe up 12mm mean the ride height will change 12mm or at all?

https://store.garagistic.com/bmw-performance-parts/bmw-3-series-parts/e30-performance-parts/E30-polyurethane-bushings/poly-95a-e30-rear-subframe-bushings-standard

The 12mm raised subframe bushings reduces camber by 4.0 - 4.5 degrees (better for a street application).
Average change is from -5 degrees to -1.5 degrees (depends on suspension setup).

god daym that's a huge change. so raising the car up 12mm should do the same right?
For something so basic to the e30 there's not allot of facts out there about it.