M3 vs. ti spring plate

[zoner]

A few weeks ago, my right front strut started feeling like it was hanging up when I would maneuver to park or pull out of a parking space. I got under it over the weekend and discovered what looked like the upper spring plate hanging up on the bearing when you turned the wheel from lock to lock.

When I replaced everything (entire front suspension minus control arms) about 6 months ago, I used the M3 bearing but ti upper plates. I'm thinking this might be my problem. Either that, or maybe I have a defective bearing? I just need to know if I can use the M3 upper plate with the ti spring (H&R) - are they the same diameter?

[spidertri]

Did you get new M3 strut hats? Good brand?

Here's some info I found:

Suspension

One of the first things you may notice: most parts catalogs list shocks/springs/struts for the E36 with 3 different fitments... 1 for the 95 M3, 1 for the 96+ M3, and 1 for all other E36s built after 6/92. This is crap.

First, be aware that all E36 coupes and sedans have the same chassis mounting points.

Second, there is no reason for 95 M3 aftermarket parts to be different from 96+ M3 aftermarket parts, unless you are looking to mix and match. Then the issue becomes spring perch diameters. At the top, stock E36 and 95 M3s have the same diameter upper spring perch (although the part number is different). The 1996+ M3s have a slightly smaller upper perch. At the bottom, non-M3 springs are a significantly larger diameter, so it follows that the lower spring perches welded onto non-M3 struts are too big for M3 springs.

From this, you can conclude that any M3 spring will fit any M3 strut, with the appropriate upper perch.

Found here: http://www.protoworks.com/cgi-bin/C-...Are_Like_Legos

[zoner]

I used Lemförder M3 (96+) strut bearings with 318ti upper spring plates (Genuine BMW). My thinking is that because of the added caster with the M3 bearing and the (assumed) corresponding increase in angle where the bottom of the bearing would contact the spacers/upper spring plate, the fact that I mixed the bearing and spring plate from different applications is causing the assembly to bind as it turns. Does this sound plausible?

If all E36's have the same diameter upper spring perch, I should be able to swap out the ti upper plates with M3 upper plates that were made to correspond with the bearings.

Thanks for that info. Dave- it is very helpful and I think it pretty much answered my questions.

[familytruckster]

Any new info on this? One of the next mods I'm planning is M3 strut mounts.

[zoner]

Not yet, but just last night I ordered what I believe to be the correct parts to remedy the problem I'm experiencing. I'm planning on installing the new parts over Veteran's Day weekend, so I should be able to update the outcome shortly thereafter.

I think the problem is both with the upper perch, as well as the washer/support used between the perch and bearing. On the ti, it is a rather thin washer whereas with the M3 bearing, it appears to be much thicker and is even called a 'support' in the catalog, rather than a 'washer'. The price difference is considerable, and I'm anticipating that this 'support' provides a much greater clearance between the m3 bearing and the upper perch. Presently, there appears to be a lack of clearance between the two, which is why I think it is hanging up as the strut assembly turns from side to side.

I'll try to take pictures to document my trials, tribulations, and outcome.

[familytruckster]

Thanks! Just was looking at realoem... Interesting. At least the parts are inexpensive...Another edit.. .FCP has the M3 strut mounts for 40 bucks!

M3




ti

[zoner]

$40 is a great price for the strut mounts. I paid over $60 each for Lemförder mounts from Pelican. I've ordered parts from FCP Groton in the past for other cars and have never had a problem with service or quality. In my experience, Tischer tends to have better prices on a lot of parts but if the price is comparable, I like to order from Pelican because I can usually have it at my door the next day (their warehouse is about 20 miles away from me).

Additionally, I think the prices listed on realoem are a little dated- the upper perches were about twice the price (from both Pelican and Tischer) than the list price shown on realoem, and several other parts had a pretty wide price discrepancy (in the wrong direction, unfortunately) from those listed on realoem.

[familytruckster]

Pelican is good, ordered from there a good bit. Tischer is on my way to work, and FCP gets them to me next day.

I am really interested in what the difference is for the spring plate-and if the ti spring will work on it.

80 bucks for the strut mounts plus the washers/support is a heck of a deal over 3-600 bucks for caster/camber plates.

[familytruckster]

Might want to see if it's the spring plate hitting the strut tower due to the added neg camber. Depending on clearance it might be possible to just clearance the ti spring plate enough. The M3 spring plate is a smaller diameter than the standard 3 series. Which means the spring pad and spring are also smaller diameter.

Although that also seems strange because people run a lot of camber with CC plates and don't have issues.... Guess that could be because of less caster.

Just some thoughts...

[NiteOp]

this helped me. Because you can see the differences over the M3 and non M3 spring hats item #8 (also #9).
http://www.vorshlag.com/images/catal...tockstyles.jpg

EDIT! the link from Spiderti explains all sorry i read it after i posted....noob. the 95 and the 318ti spring hats match up.

[familytruckster]

ooh, nice pic. Makes sense. Hmm.

[familytruckster]

Any update on this?

[zoner]

I'll find out for certain this coming weekend- I pulled the old suspension out of Bodo (my '95) this past weekend and the revised setup (new spring hats and spacers) is going into Sabine (my '97) on Saturday. I'd like to do a detailed account of Bodo's dismantling just for reference's sake, but I'm usually racing against the clock and daylight when I'm trying to get too much done in a day.

I should be able to provide an update by this time next week...

[familytruckster]

Very good! Keep us posted!

[zoner]

I just realized that I never followed up on this...

It was indeed the larger diameter of the ti upper strut plate that was causing the problem, as was evidenced by a shiny, worn spot on the outermost lip of the strut plate and a corresponding wear spot where it was contacting the inside of the strut tower. The additional caster of the M3 strut bearing was pushing the whole assembly further back into tower and causing the contact when the steering wheel was maxed out all the way to lock. Now I know why the M3 plates are smaller in diameter!

The following seems to be the correct combination for anyone wanting to install M3 strut bearings to increase caster and have it function correctly on a ti (without the upper plate hitting the inside of the strut tower):

Use a '96+ M3 strut bearing (p/n 31332227897)
Use a '95 M3 upper strut perch (p/n 31332227348)
Use a '95 M3 'support' between bearing and upper plate (p/n 31332227342)
Use a '95 M3 upper spring pad (p/n 31331128523)

Do not use the ti upper plates with the M3 bearing!