E34 Subframe Reinforcement Plates - Review

[Mr Project]

Well, last week I installed Bruno's Subframe Reinforcement plates. Color me satisfied!

First my setup:
1991 535i 5-speed, 180,000 miles
Stock suspension of unknown age, stock swaybars
Recent thrust arms, pittman arms (dog bones) are pretty worn, subframe bushings have very minor cracking (probably still ok).
Tires: Goodyear Eagle HP 215/60/15 in front, 225/60/15 in rear

Installation:
I was removing my A/C for conversion and thought I'd throw these in. Not counting 15 minutes of jacking the car up and setting it down, this took maybe 15 minutes to install. I had the car on jack stands, supported the rear suspension with the jack, and used my impact wrench to pop the 22mm and 13mm nuts off. Then, wipe the dirt off the steel parts, slap Bruno's plate in, and bolt it back up. Easy as pie. I didn't have a torque wrench at that moment, so I tightened them to around 100 foot-pounds with my calibrated elbow and cheater bar. Also, he calls these 'plates', but they are some kind of urethane, not steel or aluminum. Have no fear.

Driving impressions: (100 miles of highway, 50 miles of city, about a week so far)
The first thing I noticed, and probably the biggest difference, is the 'mushy' and 'squatty' feel is VERY much reduced in certain situations. When I pull out of my neighborhood, I often have to accelerate pretty hard through 1st and 2nd gear while turning left. That 1-2 shift under power while turning used to create a big 'squat and squirm' movement in the rear suspension. Not anymore! Power delivery is more controlled and less dramatic, with a much greater sense of firm body and rear suspension connection.

This effect is rather noticeable in applying power in corners. There is a much reduced tendency to 'squat and squirm' at all times when applying power in a corner, with a much more satisfying and controlled 'feel'. Color me impressed!

I don't know yet if this has any effect on wheel hop. (haven't tried any shenanigans)

NVH: I am getting to be a big wuss in my old age, so I was concerned that this modification might increase my NVH levels unacceptably. Those fears were unwarranted. No significant NVH increase at all. There might be a slight increase in audible impact harshness in the rear suspension, but it is so slight as to be totally undetectable with any type of other noise...radio, sunroof, fan motor, etc. Around town with our horrible roads, there is no significant ride difference I can detect.

So, for the price, I highly recommend these. I think they will be sufficient for me to delay my plan to replace all of my rear suspension bushings for a while. I'll do my dogbones sometime and that will probably be good for me for a while.

Armen - no affiation with Bruno or racingking.ca

http://www.racingking.ca/Canada/Scri...?idproduct=693

[George M]

Nice write up Mr. P...you tap all the bases. Kudo's to Bruno for introducing this new product!
George

[Bruno]

For storing my tire for so long ahhahaha.
I am still hopping to see you the 27th July in the evening if that is ok with you.

[George M]

You don't have to bring a set Bruno...just come on over.
I would really like to install fresh sub frame bushings but don't feel like renting the fancy BMW tool from Brett. If you have the BMW subframe extractor/installation tool...bring that, and when I am done, I will ship it back to you.
George

[Bruno]

developping parts for the E34/E32...

I am picking up the thrust arms bushing inserts this afternoon.
I have 8 sets available, and I will probably put them on the website tomorrow or monday.

[Scott H]

I'll be halfway to Detroit next weekend near Kalamazoo.....I could meet you guys and hand you cash for a set Bruno. Install them, and drive them back home to Chicago......hmmmmm

and......I have a few things to talk to Bruno about......G-mann you know what is up so far

[Mr Project]

I do want to thank you, Bruno... this is a great product at a great price, and nobody else is committed to our community like this!

[Bruno]

I'll be halfway to Detroit next weekend near Kalamazoo.....I could meet you guys and hand you cash for a set Bruno. Install them, and drive them back home to Chicago......hmmmmm

and......I have a few things to talk to Bruno about......G-mann you know what is up so far

I will be in Michigan the 27th in the evening until the 29th of July, then I am going back to Canada with 2 racing seats, 2 harness, 1 tire, 3 sets of rims, a trailer hitch...

[George M]

...a compressed air tank pressure gauge and misc. MAF stuff...

George

[jplacson]

Are these reinforcements needed? I mean, is the E34 suject to the same subframe failure as the E36 and E46, which is why these plates are needed?