Touring Rear Spring Question

[bimmerd00d]

I'm on the hunt for some stiffer springs that will raise the wagon. It came with SLS deleted and B&G springs with Bilsteins all around. I'm not the boy racer who likes to tuck the ass end to the ground. I want to use my touring. SO, i know 525i sedan springs are too soft for the rear. Are E34 540i rear springs the same rate as the 525i? What about E32 735/740i springs? The Bilsteins out back work pretty well.

We're just talking rears here, the front is right where i like it.

[genphreak]

e32 would be stiffest, I expect 750 would be stiffest, followed by 740 and 735 ones (may be the same). Your current ones might be sedan springs. I am going to fit e32s to mine one day when I find a set...

[Tiger]

You have to make sure the diameter of the spring coils are the same.

The difference between the standard suspension and SLS suspension is in the rear spring... SLS spring is usually about 1/2 coil shorter due to SLS assisted support. If they have wagon spring without SLS... that would be it but I think all wagons came with SLS... so no market or desire to produce that.

As for sedan springs... the rear spring is usually the same and sometime the front spring is different to support the engine.

[bimmerd00d]

You have to make sure the diameter of the spring coils are the same.

The difference between the standard suspension and SLS suspension is in the rear spring... SLS spring is usually about 1/2 coil shorter due to SLS assisted support. If they have wagon spring without SLS... that would be it but I think all wagons came with SLS... so no market or desire to produce that.

As for sedan springs... the rear spring is usually the same and sometime the front spring is different to support the engine.

As i stated before, SLS has been removed and has B&G's all around. In theory couldn't I use E32 rear springs and shock mounts? The struts are the same i thought. I read somewhere that the coils are a tad thicker, but that might have just been teh fronts springs.

[Tiger]

http://forums.bimmerforums.com/forum/archive/index.php/t-370223.html

Make phone calls.

[bimmerd00d]

http://forums.bimmerforums.com/forum/archive/index.php/t-370223.html

Make phone calls.

Well that doesn't help me, i'm already at that point. It's lowered now, it doesn't bottom out, it just looks tacky to me. It functions/handles like it's on rails. Bav Auto is overpriced crap. My SLS has already been deleted, i dont need someone to tell me how to do that. My question in here was if E32 springs work in an E34. Make phone calls...........read my thread :D

[genphreak]

AFAIK, e32 struts and springs are the same as e34, just the spring and of course shock grades are different. Be sure to check the strut top mounts, they wear a lot and besids, are different on cars with SLS to non SLS, I'm not sure how, but they have different part numbers... I've never heard of anyone changing them during a conversion tho

[Tiger]

Being a prick does not encourage people to help you... you will see.

I know what you want. I advised you to make sure the spring diameter are the same. This is important. Genphreak did not say this in his first post.

I told you usually all sedan rear spring is the same rate, just the front is different due to engine.

SLS springs are shorter in the back... you bought a wagon lowering spring with SLS kit from B&G. There is no w/o SLS spring kit.

I spent time to search for SLS delete spring that doesn't cost $2000. I saw that.

Then I couldn't find any more info on the SLS delete spring that brings it to stock height... and that is when I told you to make calls.... you didn't say you did made calls.

I spent 3 hours of hard search for you... out of generousity. That's the way it work on forum. I don't have 3 hours to waste for unappreciative folks.

So good luck from here on.

[Brandon J]

Wow, I have not posted in a long long long time.

If you guys remember, I am the one who held all those e34 big meets that was also featured int he Roundel.

First off, never assume spring rates just because of the BMW model. Just because you have a 740 does not mean it has a higher spring rate than a 735 for the rears.

Bimmerd00d has actually been with the community since roadflea.

Anyways, I understand what Bimmerd00d is asking. He is using his wagon as a daily driver for point A to point B. Spring rates don't necessarily mean the car height will raise. I have done over 2 dozen sets of suspension on e34s and various combinations of springs and shocks. Years ago I did catalog the spring rates and spring numbers, but that was 2 computers ago and I don't have my spreadsheets.

I guess what Bimmerd00d is looking for is just a cheaper alternative to the rear. Oh, there is a $10 solution to the handle the sls as I have done it on 2 M5s and 2 wagons. All US wagons came with sls, but not all Euro wagons came with sls. The correct way to set the height is to use Euro wagon springs. That will give the correct height as well as correct spring rate. Now, if you don't care as much about the spring rate, then go ahead and play with the springs. A stock sedan spring along with the added rear weight of the wagon will in affect lower the stock height of that spring, thus better matching the height of your front B&G springs.

As far as the height and matching, there is the static height, then the suspension travel variance in motion. So, static height should be good, but my only concern is when the car moves, tucks on acceleration, and handling bumps. The matching of the spring height, rate, strut travel and strut compression and rebound settings can affect your ride. As long as you just use the touring from point A to point B as a daily driver, then I am assuming this isn't as much of a concern. Plus, your roads in Texas are pretty good roads. If it were me, I would find matching sets, but that's because it is me. My roads here in Chicago need more balanced and compliant suspension, even for daily driving.

Hope that helps. Either way, good luck with your venture.

[bimmerd00d]

Wow, I have not posted in a long long long time.

If you guys remember, I am the one who held all those e34 big meets that was also featured int he Roundel.

First off, never assume spring rates just because of the BMW model. Just because you have a 740 does not mean it has a higher spring rate than a 735 for the rears.

Bimmerd00d has actually been with the community since roadflea.

Anyways, I understand what Bimmerd00d is asking. He is using his wagon as a daily driver for point A to point B. Spring rates don't necessarily mean the car height will raise. I have done over 2 dozen sets of suspension on e34s and various combinations of springs and shocks. Years ago I did catalog the spring rates and spring numbers, but that was 2 computers ago and I don't have my spreadsheets.

I guess what Bimmerd00d is looking for is just a cheaper alternative to the rear. Oh, there is a $10 solution to the handle the sls as I have done it on 2 M5s and 2 wagons. All US wagons came with sls, but not all Euro wagons came with sls. The correct way to set the height is to use Euro wagon springs. That will give the correct height as well as correct spring rate. Now, if you don't care as much about the spring rate, then go ahead and play with the springs. A stock sedan spring along with the added rear weight of the wagon will in affect lower the stock height of that spring, thus better matching the height of your front B&G springs.

As far as the height and matching, there is the static height, then the suspension travel variance in motion. So, static height should be good, but my only concern is when the car moves, tucks on acceleration, and handling bumps. The matching of the spring height, rate, strut travel and strut compression and rebound settings can affect your ride. As long as you just use the touring from point A to point B as a daily driver, then I am assuming this isn't as much of a concern. Plus, your roads in Texas are pretty good roads. If it were me, I would find matching sets, but that's because it is me. My roads here in Chicago need more balanced and compliant suspension, even for daily driving.

Hope that helps. Either way, good luck with your venture.

Ahh now this is how these posts should go, informative without all the BS. I was thinking of going the euro 525iT sport spring route. If i can get ahold of a pair, i'll just get the full set of 4 and be done with it. The E32 springs are just super easy to find around here, hence the reason for this thread.

[genphreak]

Am pretty sure that 740 will be heavier springs than 735; so long as they are both from iL bodies. The weight distribution of the 740 is different to 735, the engine being a bit lighter, the trans much heavier and the rear of the 740 heavier by a maybe 25kg, so I am pretty sure 740 rears would have much higher rates and make the car a little higher than normal too. Of course old rears seem to sag, so maybe all that will just work out perfectly height wise. The front springs would certainly be very different, but if using the touring for carrying things, the springs will need a stiffer rate. I reckon from a balanced point of view 735 spring may be a much safer bet. I'd definately try those first.

Of course, you can alwasy go to a spring company and have them make something 'just right'- they simply measure the front spring rates, the car weight distribution and overall travel- do some calcs and then make the springs.

BTW: Be sure to lay something down in the rear, the carpet doesn't take much of a beating :)

[genphreak]

Hey Tiger, I'm sure he didn't mean it like that... Of course without more words, it can often be hard to tell. Try erring on the side of 'goodwill', I just can't imagine why BD would be deliberately poking like that. This forum is hardly bf afterall...

[bimmerd00d]

Hey Tiger, I'm sure he didn't mean it like that... Of course without more words, it can often be hard to tell. Try erring on the side of 'goodwill', I just can't imagine why BD would be deliberately poking like that. This forum is hardly bf afterall...

Not at all, but if someone pokes the bear, the bear attacks :D

[Brandon J]

Am pretty sure that 740 will be heavier springs than 735; so long as they are both from iL bodies. The weight distribution of the 740 is different to 735, the engine being a bit lighter, the trans much heavier and the rear of the 740 heavier by a maybe 25kg, so I am pretty sure 740 rears would have much higher rates and make the car a little higher than normal too. Of course old rears seem to sag, so maybe all that will just work out perfectly height wise. The front springs would certainly be very different, but if using the touring for carrying things, the springs will need a stiffer rate. I reckon from a balanced point of view 735 spring may be a much safer bet. I'd definately try those first.

Of course, you can alwasy go to a spring company and have them make something 'just right'- they simply measure the front spring rates, the car weight distribution and overall travel- do some calcs and then make the springs.

BTW: Be sure to lay something down in the rear, the carpet doesn't take much of a beating :)

Again, we shouldn't assume. Just because it "makes sense" doesn't mean to go that way. I have seen many many times that the wrong outcome happen. Why? Because there are so many options and variations in the BMWs. I understand your logic about the iL, but unless you have seen these different springs like I have, I wouldn't assume. Plus iL's were sls too. The height does not depend on spring rate. Spring rate is for the ride. You can always do the old "chop job" and cut a spring coil and you then get a stiffer rate spring with lowering. Again, he can play, or get the euro non-sls spring set. Or he can go cheap and play with existing springs. To get springs made is more than just those simple calculations you mentioned, especially if there is a variable spring rate component. Have you ever gotten springs made? It can be a pain the the rear! Especially waiting to get them made and hoping they actually work right. I have seen custom springs that were not made right from reputable companies. The coil spacing was wrong and even not enough coils. Ha, corners also were different heights by more than 1/2 in. and that is when everything was settled.

The best solution is to go with what has been tried and tested. You know the result and can trust the outcome. Plus, it is less work overall. Find a matched set for non-sls euro sport. Many wagon owners have done this when they deleted their sls and want a factory sport ride, but nothing too low out back. Or, look for other aftermarket springs that are specifically for sls rear delete. I have seen many people go cheaper and end up spending more in the end to correct things.

[genphreak]

Again, we shouldn't assume. Just because it "makes sense" doesn't mean to go that way. I have seen many many times that the wrong outcome happen. Why? Because there are so many options and variations in the BMWs. I understand your logic about the iL, but unless you have seen these different springs like I have, I wouldn't assume. Plus iL's were sls too. The height does not depend on spring rate. Spring rate is for the ride. You can always do the old "chop job" and cut a spring coil and you then get a stiffer rate spring with lowering. Again, he can play, or get the euro non-sls spring set. Or he can go cheap and play with existing springs. To get springs made is more than just those simple calculations you mentioned, especially if there is a variable spring rate component. Have you ever gotten springs made? It can be a pain the the rear! Especially waiting to get them made and hoping they actually work right. I have seen custom springs that were not made right from reputable companies. The coil spacing was wrong and even not enough coils. Ha, corners also were different heights by more than 1/2 in. and that is when everything was settled.

The best solution is to go with what has been tried and tested. You know the result and can trust the outcome. Plus, it is less work overall. Find a matched set for non-sls euro sport. Many wagon owners have done this when they deleted their sls and want a factory sport ride, but nothing too low out back. Or, look for other aftermarket springs that are specifically for sls rear delete. I have seen many people go cheaper and end up spending more in the end to correct things.

Indeed, all very valid points. I dare say the best way is seldom to try with these cars- or assume- I too have learned this (too many times). The cheap route would perhaps be a spring mount that spaces the spring the desired height above the strut perch- If one can make one that won't break that is...

[MicahO]

Ahh now this is how these posts should go, informative without all the BS. I was thinking of going the euro 525iT sport spring route. If i can get ahold of a pair, i'll just get the full set of 4 and be done with it. The E32 springs are just super easy to find around here, hence the reason for this thread.

Like Brandon, I haven't posted in a long damn time either.

Where are you located? I've got a pair of non-sls Touring Sport springs bought through Maximillian back in 2000 or 2001. I'd have to dig back and see if I've got the receipts or emails, but I spec'd them for my '92 Touring, they should be well-suited to any other US-spec Touring.

Never used, I installed the front sport springs and then never got around to the rear and the SLS-delete.

email me, micah.oc at gmail. I'm travelling for the next 2 weeks......

[bimmerd00d]

Like Brandon, I haven't posted in a long damn time either.

Where are you located? I've got a pair of non-sls Touring Sport springs bought through Maximillian back in 2000 or 2001. I'd have to dig back and see if I've got the receipts or emails, but I spec'd them for my '92 Touring, they should be well-suited to any other US-spec Touring.

Never used, I installed the front sport springs and then never got around to the rear and the SLS-delete.

email me, micah.oc at gmail. I'm travelling for the next 2 weeks......

very cool, emailed :)