E23 Suspension Question

[DSpoljaric]

What OD size are the fronts and rears? The front OD can be 174, 180, or 190mm. Rear is either 114 or 125mm.

[BONDOSPECIAL]

when I measured my old 745i it had 180mm front. I measured 735i rears at 114mm. 735i front should be 174mm. Not sure what size the 745i original rears would be. The only way to know for sure is measure your car. You never know what a previous owner swapped on there (on my old car I found the previous owner had swapped 735i rear spring/strut assys on there to delete the load levelling original suspension)

[DSpoljaric]

I've gone back and forth with H&R over the last two months trying to get the correct config for my 86 745i. OE front is 180mm and rear is 114mm. H&R does not offer the 180mm front any longer. So I received yesterday a set of 174mm front / 114mm rear and will install them soon to verify that there is not issue with the 174mm vs 180mm for the front application. Based on everything I've measure so far, it looks promising.

Take it from me, be sure to measure your e23 front and rear springs OD before buying any springs.

[BONDOSPECIAL]

That is a pretty significant difference in coil spring diameter which is going to affect whether the spring sits in the spring pockets correctly. I replaced struts on my 180mm e23 setup and had them apart, and don't remember there being enough room to fudge a .25" smaller diameter spring in the same housing. Changing to donor 735i housings set up for a 174mm spring should not be a big deal though

[DSpoljaric]

We shall see! I'll report back soon.

[Hit Man X]

Well...

31311119707 and 31311119708 front strut housings both cross for US and ECE cars. Borrowed from RealOEM.com when I searched for 11/84 745i strut housing.



Part 31311119707 (LEFT FRONT SPRING STRUT) was found on the following vehicles:
E23: Details on E23
E23 733i Sedan, USA
E23 735i Sedan, USA
E23 728 Sedan, Europe
E23 728i Sedan, Europe
E23 728iS Sedan, Europe
E23 730 Sedan, Europe
E23 732i Sedan, Europe
E23 733i Sedan, Europe
E23 735i Sedan, Europe
E23 745i Sedan, Europe

Details for all

[CMG]

I will be putting up a for sale thread soon they are both the same size springs. FYI i assume we have all read about supposed differences in spring diameters, but i have personally had up to 10 different oem and aftermarket sets and they all have the same diameter. If you guys have different diameters then what year and models are they off of? I posted threads with info a year or two ago when i was doing my suspension.

[DSpoljaric]

1986 745i
Front: 180mm
Rear: 114mm

[ltflint]

I have some Motorsport series lowering springs I would be willing to sell.

These are the best springs for an E23 IMHO.

I love the Motorsport series springs on my car.

[Hit Man X]

How do they ride versus Dinans?

[BoolJames]

Roughly how much u paid for your whole Coilover set up? If u dnt remeber it's okay.

[CMG]

These are the best springs for an E23 IMHO.

I love the Motorsport series springs on my car.

what other springs have you had to compare them with though? The complete dinan set up is by far the best e23 suspension. The ST springs are pretty darn close to Dinan too. I would love to get my hands on some racing dynamics springs as they are the only progressive ones and i'm curious how they feel. I can't speak for motorsports series or h&r but i know bavauto are on the bottom of the list for springs. The dinan and st springs i have are both about 6" in front and 3.5" in rear, i'll check out a better conversion. Whoops looks like i need OD

[DSpoljaric]

The H&R are progressive as well.

[CMG]

Yeah i just checked the pics it looks like it. I'm sure the h&r work good but last i checked they were expensive too

[DSpoljaric]

About $350 including shipping.

[CMG]

Looks like the dinan and st are 180mm and 114mm which seems to be most springs

[ltflint]

what other springs have you had to compare them with though? The complete dinan set up is by far the best e23 suspension. The ST springs are pretty darn close to Dinan too. I would love to get my hands on some racing dynamics springs as they are the only progressive ones and i'm curious how they feel. I can't speak for motorsports series or h&r but i know bavauto are on the bottom of the list for springs. The dinan and st springs i have are both about 6" in front and 3.5" in rear, i'll check out a better conversion. Whoops looks like i need OD

Driven two 745i's on Dinan springs. I find the Motorsport series to be a better all around set up, but you say the Dinan is the best by far, you must be right.

[CMG]

I'm talkin dinan springs and dinan valved billies combo. I've never ridden the mosport so they might be similar as well. Are they progressive? Got pics? This stuff was gone over last year or two in my threads but other than springs and sways and of course strut bars the only other suspension parts there were was the dinan camber plates. Using fresh billies makes a huge difference when adding springs. Imo just having fresh oem bushings and ball joints with springs and sways and fsb is about all you can do with these cars. I highly recommend it.

[SicStang03]

These are the best springs for an E23 IMHO.

I love the Motorsport series springs on my car.

I didn't know you were on Motorsport series springs. Can you provide any details on the springs? Also, a pic of the way your car sits? You have HD Bills paired with them?

[ltflint]

The springs are paired with custom valved Bilstein sports. They were sold as a package back in the 80's. I have a copy of the catalog somewhere, but I believe Hitman has a PDF of it.

The car also has the Motorsport Series swaybars. 29mm up front.

When I bought the car, it appeared that all of the suspension stuff had been on there for a very long time, but it rode and handled very well on the drive home to Memphis from Phoenix, AZ. I also did a trip over to Vintage in Winston Salem. Last spring, I sent the rear Bilstein Sports back to Bilstein and had them rebuilt. I need to do the fronts, just haven't gotten around to it.

The car handles just as well as the two Dinan sprung cars that I've driven, and the ride is actually better. I know that's subjective, but I have put about 12,000 miles on the car since I bought it a little over two years ago and it is a superior road trip car as far as comfort and handling as any of the 5 cars that I currently own.

I'll try to dig up the catalog if Eric doesn't beat me to it and see if it has the spring rates.

[Hit Man X]

I have it. If anyone wants it, drop me a note. I even have a sticker from them

Also have factory ECE prospective brochure showing the price (in DM) and code of all options. Keith (with the Hartge E23) sent it to me.

[CMG]

For suspension in general having fresh joints and bushings as well as good wheels makes huge handling improvements. The sways, springs and billies are the icing on the cake. Has anybody searched somehow all the old car magazines for mention of motorsport series from back in the day? So Flint you're saying your stuff was on the car years ago? That's interesting cuz that meand it wasn't part of that nos lot. I didn't realize they had matching billies too. Does it have the adjustable endlinks too?

[Hit Man X]

Yes, three way front and rear.

[ltflint]

Yes, three way front and rear.

Exactly.

[CMG]

Not holes i meant adjustable length heim ball joints type links?