The Definitive Suspension Guide for your E36 M3

[Herb]

Slightly OT : Is that you joenationwide in November's GRM UTCC article? 39th overall, 18th in class.

[joenationwide]

Slightly OT : Is that you joenationwide in November's GRM UTCC article? 39th overall, 18th in class.

Yeah! That was me! Did that come out already?

Can you scan the pic and post it?

[acastillo]

As far as the AST 4100s what spring rate did you go with?

400/500. The rear 500's I received were a bit short (120/80), so they're sending me slightly longer, softer springs (140/70).

Thanks for the detailed explanation on increased bump travel...certainly makes sense.

Tough to say which made a bigger improvement...AST's or OEM bushings, since the A/B comparison is 7mo apart.

I will say though that even small but sharp road irregularities or expansion joints, that would not be enough to cause the koni/eibach suspension to bottom out on the bumpstops, previously used to transmit harshly into the cabin. Immediately after the AST install the car seems to glide over these small bumps/joints with less perceived harshness. Whether it be increased bump travel, or the difference between the dampeners, I am happy.

[Herb]

Yeah! That was me! Did that come out already?

Can you scan the pic and post it?

Came in yesterday. It kills me when they do the month gap publications !
No scanner, but I snapped pics with my phone real quick.

[joenationwide]

Came in yesterday. It kills me when they do the month gap publications !
No scanner, but I snapped pics with my phone real quick.

Thanks Herb!

Wow, thats awesome, they included the thank yous to my friends who got my car back together in 3 days!

Its funny to see that I was 18th, but considering my class was "anything more than 4 cylinders" I don't feel bad. Its a street car vs. race cars.

Herb, btw...I always liked your S52 E30!

[Herb]

Thanks, I do miss it , and it has more HP/tq then when I had it. At this last track day I got to ride in it, and if I had more time that day I could have driven it too.

On topic, I see TRM coilovers in my future .

[BryDog]

Anyone have a perspective on the Turner H/I stock suspension?
http://www.turnermotorsport.com/html...D=E36TMSISTOCK

And what changes to the Definitive Guide would you make if you were to change to R-Compound tires?

* Great thread btw.

BryDog

[Frankiez]

What is the "divider" if I want change lbs/inch to Kg/cm?

[M3Alpine99]

The Poly RTAB(and other bushing locations as well) has been going on for years. Still haven't seen a comparo on the same track back to back in the same conditions to give some sort of factual numbers to compare. I do track days and the AKG RTABs have worked just fine. Until something that comes out and makes a more firm statement I am fine with running them.

[EuroPhreak07]

Subscribed

[SG_M3]

What is the "divider" if I want change lbs/inch to Kg/cm?

divide by 56

(1kg/mm)*(25.4mm/1in)*(2.2lb/1kg) => 1 kg/mm = 55.88 lb/in

[Frankiez]

In the first page there is a mention of "f650" "R700". f meaning front and r rear, but is that figure 650/700 lbs/inch or something else, if it is something else, what it is converted to Kg/cm? Usually I have seen European manufacturers using 90kg front and 120 rear? Is the divider then 5.6?

[SG_M3]

In the first page there is a mention of "f650" "R700". f meaning front and r rear, but is that figure 650/700 lbs/inch or something else, if it is something else, what it is converted to Kg? Usually I have seen European manufacturers using 90kg front and 120 rear? Is the divider then 5.6?

correct, 650 lb/in and 700 lb/in, in kg/mm it is 11.6 kg/mm and 12.5 kg/mm

Kg/mm = lb/in:
16 = 896
15 = 840
14 = 784
13 = 728
12 = 672
11 = 616
10 = 560
9.0 = 504
8.5 = 476
8.0 = 448
7.5 = 420
7.0 = 392
6.5 = 364
6.0 = 336
5.5 = 308
5.0 = 280
4.5 = 252
4.0 = 224
3.0 = 168
2.0 = 112

[cmzwirner]

Joe,

Im planning to get into autox this season, but i want to keep my track build as low budget as possible so i have leftover cash for driving schools/HPDE's. I also dont want to dump thousands into it, and realize i dont like it.

But anyways... My current e36 m3's setup right now is:
Square 7.5" DSII's on 225x45R17 star specs
Koni Yellow SA w/ Eibach Pro Kit
Stock front/rear swaybar

I plan to do one or two events to see if i like it, and if i do ill start outfitting the car with more suitable parts.

Ill be replacing the eibach pro kit springs with the GC coilover conversion kit, adding a front sway, and putting in camber shims for -2.5 up front. I also have an m50 manifold kit here that i might install. But i fear that may trow me out of a class that i can be competitive in.

What do you think of these plans? Anything else you would recommend?

[CGS12]

Joe,

Im planning to get into autox this season, but i want to keep my track build as low budget as possible so i have leftover cash for driving schools/HPDE's. I also dont want to dump thousands into it, and realize i dont like it.

But anyways... My current e36 m3's setup right now is:
Square 7.5" DSII's on 225x45R17 star specs
Koni Yellow SA w/ Eibach Pro Kit
Stock front/rear swaybar

I plan to do one or two events to see if i like it, and if i do ill start outfitting the car with more suitable parts.

Ill be replacing the eibach pro kit springs with the GC coilover conversion kit, adding a front sway, and putting in camber shims for -2.5 up front. I also have an m50 manifold kit here that i might install. But i fear that may trow me out of a class that i can be competitive in.

What do you think of these plans? Anything else you would recommend?

Have you ever been to an autocross before? How many track/HPDE days do you have?

[joenationwide]

Anyone have a perspective on the Turner H/I stock suspension?
http://www.turnermotorsport.com/html...D=E36TMSISTOCK

And what changes to the Definitive Guide would you make if you were to change to R-Compound tires?

* Great thread btw.

BryDog

When running R-comps, you may want to go up in spring rate to compensate for the extra body roll due to extra grip. For me, I never changed my front rate of 525#, but I did go up in the rear from 450# to 550# and now 650#. Those rates still work really well on street tires. Upping the rear rates was actually more to help make the car more neutral and less understeery in long sweepers (which you tend to see more on track). Another thing with R-comps, you need dampers that can handle more spring and control the car better. Thats why I switched from konis to PSS9 dampers, the PSS9 dampers can control/damp body motions better.

The Poly RTAB(and other bushing locations as well) has been going on for years. Still haven't seen a comparo on the same track back to back in the same conditions to give some sort of factual numbers to compare. I do track days and the AKG RTABs have worked just fine. Until something that comes out and makes a more firm statement I am fine with running them.

I installed poly RTABs before OEM RTABs with limiters became the hip thing to do. I have no problems with my poly RTABs after 4 years and maybe 60 track days and 60 autoxes. Either solution seems to work fine.

divide by 56

(1kg/mm)*(25.4mm/1in)*(2.2lb/1kg) => 1 kg/mm = 55.88 lb/in

I think I saw your old M3 at Summit Point last weekend.

Joe,

Im planning to get into autox this season, but i want to keep my track build as low budget as possible so i have leftover cash for driving schools/HPDE's. I also dont want to dump thousands into it, and realize i dont like it.

But anyways... My current e36 m3's setup right now is:
Square 7.5" DSII's on 225x45R17 star specs
Koni Yellow SA w/ Eibach Pro Kit
Stock front/rear swaybar

I plan to do one or two events to see if i like it, and if i do ill start outfitting the car with more suitable parts.

Ill be replacing the eibach pro kit springs with the GC coilover conversion kit, adding a front sway, and putting in camber shims for -2.5 up front. I also have an m50 manifold kit here that i might install. But i fear that may trow me out of a class that i can be competitive in.

What do you think of these plans? Anything else you would recommend?

I think your plan sounds great. The GC coilovers will really improve the car's autox abilities. I'd follow the spring rate suggestions in the guide. I'm dead set on 525# front spring rates, and anything from 450-550# rear rates. I think you'll absolutely love it. I'd also get a larger front sway bar and set it to full stiff for autox. With the 525# front rates and a larger front sway bar, your M3 will respond instantly to steering inputs without any noticeable lag due to front body roll. This will allow you to stay ahead of the course and not get behind. Slaloms will be your playground. For long sweepers, you'll need to learn to rotate the car by lift throttle oversteer.

A lot of people say don't mod the car until you are a good driver. I think now I can finally respond to that statement.

While I agree, learning to autox (or as is most commonly seen) learning to track a car that is fully modded with extra power, crazy suspension, and race tires is a bad idea. You'll never be able to explore the limits and the car will always be faster than you.

But at the same time, driving a stock car can be very limiting and frustrating, even when learning.

So my suggestion to a novice wanting to mod the car and the driver simultaneously, is to only mod the suspension in order to maximize the contact patch of all 4 tires. In other words, go out and get a decent suspension and good alignment, and then learn to drive the car on regular street tires. This way, the car's suspension is working as it should, and wearing the tires evenly, but the car's limits are easy to explore because the tires aren't all that grippy. And at the same time, you'll learn to tweak and adjust the suspension to suit your driving style. You may want to set it up fast and loose, or tight and tidy.

Thats how I learned to become a good driver. I bought suspension for my M3, and then I autoxed on pilot sport all seasons for a year. I was near bottom of the pack. The next year I got azenis, and was top 3-4. The year after that I got Neovas and was running toe-to-toe with national trophy winners. Both the car and I got better simultaneously.

[BimmerBoyUSMC]

When running R-comps, you may want to go up in spring rate to compensate for the extra body roll due to extra grip. For me, I never changed my front rate of 525#, but I did go up in the rear from 450# to 550# and now 650#. Those rates still work really well on street tires. Upping the rear rates was actually more to help make the car more neutral and less understeery in long sweepers (which you tend to see more on track). Another thing with R-comps, you need dampers that can handle more spring and control the car better. Thats why I switched from konis to PSS9 dampers, the PSS9 dampers can control/damp body motions better.

I installed poly RTABs before OEM RTABs with limiters became the hip thing to do. I have no problems with my poly RTABs after 4 years and maybe 60 track days and 60 autoxes. Either solution seems to work fine.

I think I saw your old M3 at Summit Point last weekend.

I think your plan sounds great. The GC coilovers will really improve the car's autox abilities. I'd follow the spring rate suggestions in the guide. I'm dead set on 525# front spring rates, and anything from 450-550# rear rates. I think you'll absolutely love it. I'd also get a larger front sway bar and set it to full stiff for autox. With the 525# front rates and a larger front sway bar, your M3 will respond instantly to steering inputs without any noticeable lag due to front body roll. This will allow you to stay ahead of the course and not get behind. Slaloms will be your playground. For long sweepers, you'll need to learn to rotate the car by lift throttle oversteer.

A lot of people say don't mod the car until you are a good driver. I think now I can finally respond to that statement.

While I agree, learning to autox (or as is most commonly seen) learning to track a car that is fully modded with extra power, crazy suspension, and race tires is a bad idea. You'll never be able to explore the limits and the car will always be faster than you.

But at the same time, driving a stock car can be very limiting and frustrating, even when learning.

So my suggestion to a novice wanting to mod the car and the driver simultaneously, is to only mod the suspension in order to maximize the contact patch of all 4 tires. In other words, go out and get a decent suspension and good alignment, and then learn to drive the car on regular street tires. This way, the car's suspension is working as it should, and wearing the tires evenly, but the car's limits are easy to explore because the tires aren't all that grippy. And at the same time, you'll learn to tweak and adjust the suspension to suit your driving style. You may want to set it up fast and loose, or tight and tidy.

Thats how I learned to become a good driver. I bought suspension for my M3, and then I autoxed on pilot sport all seasons for a year. I was near bottom of the pack. The next year I got azenis, and was top 3-4. The year after that I got Neovas and was running toe-to-toe with national trophy winners. Both the car and I got better simultaneously.

You, sir, are a true inspiration.

[CGS12]

When running R-comps, you may want to go up in spring rate to compensate for the extra body roll due to extra grip. For me, I never changed my front rate of 525#, but I did go up in the rear from 450# to 550# and now 650#. Those rates still work really well on street tires. Upping the rear rates was actually more to help make the car more neutral and less understeery in long sweepers (which you tend to see more on track). Another thing with R-comps, you need dampers that can handle more spring and control the car better. Thats why I switched from konis to PSS9 dampers, the PSS9 dampers can control/damp body motions better.




I think your plan sounds great. The GC coilovers will really improve the car's autox abilities. I'd follow the spring rate suggestions in the guide. I'm dead set on 525# front spring rates, and anything from 450-550# rear rates. I think you'll absolutely love it. I'd also get a larger front sway bar and set it to full stiff for autox. With the 525# front rates and a larger front sway bar, your M3 will respond instantly to steering inputs without any noticeable lag due to front body roll. This will allow you to stay ahead of the course and not get behind. Slaloms will be your playground. For long sweepers, you'll need to learn to rotate the car by lift throttle oversteer.

A lot of people say don't mod the car until you are a good driver. I think now I can finally respond to that statement.

While I agree, learning to autox (or as is most commonly seen) learning to track a car that is fully modded with extra power, crazy suspension, and race tires is a bad idea. You'll never be able to explore the limits and the car will always be faster than you.

But at the same time, driving a stock car can be very limiting and frustrating, even when learning.

So my suggestion to a novice wanting to mod the car and the driver simultaneously, is to only mod the suspension in order to maximize the contact patch of all 4 tires. In other words, go out and get a decent suspension and good alignment, and then learn to drive the car on regular street tires. This way, the car's suspension is working as it should, and wearing the tires evenly, but the car's limits are easy to explore because the tires aren't all that grippy. And at the same time, you'll learn to tweak and adjust the suspension to suit your driving style. You may want to set it up fast and loose, or tight and tidy.

Thats how I learned to become a good driver. I bought suspension for my M3, and then I autoxed on pilot sport all seasons for a year. I was near bottom of the pack. The next year I got azenis, and was top 3-4. The year after that I got Neovas and was running toe-to-toe with national trophy winners. Both the car and I got better simultaneously.

Joenationwide its interesting you have 525f and 650r spring rates on your car
now, as a friend of mine swears by 500f/600r for spring rates with his TC Kline suspension on his E36 M3. I really wonder if this is near an ideal split in front and rear spring rates. My friends M3 is so smooth on track compared to my fresh OEM suspension. His car corners so flat its ridiculous. His suspension has no drama, no pitching and rolling, no getting unsettled on bumps like mine. After doing a complete rear and front suspension rebuild this winter I really didn't have money for coilovers, well it was more of a choice of buy suspension or do lots of HPDE's. So I chose working on driver instead. I'm going to try R-comps for my next event in June, really wondering how that will work with soft stock springs, and dampers.

So Joe what would I need to to do to get into NASA TT. I just got promoted to HPDE4 with NASA and have been running BMWCCA advanced group for a while. By the way The HPDE4/instructor/TT run groups are nuts compared to BMWCCA. Its almost like your out there racing!

[cmzwirner]

Have you ever been to an autocross before? How many track/HPDE days do you have?

Nope! But i m going to a test/tune day on saturday, and an autox on sunday.

And joe, thanks for the input! Im starting ot with the GC coilover kit. Well see how these do at my first event. I hope to use this event to learn the dynamics of the suspension and car. If i place down bottom, oh well.

I went with 525f/500R. Hopefully this will suit me well!

[joenationwide]

Joenationwide its interesting you have 525f and 650r spring rates on your car
now, as a friend of mine swears by 500f/600r for spring rates with his TC Kline suspension on his E36 M3. I really wonder if this is near an ideal split in front and rear spring rates. My friends M3 is so smooth on track compared to my fresh OEM suspension. His car corners so flat its ridiculous. His suspension has no drama, no pitching and rolling, no getting unsettled on bumps like mine. After doing a complete rear and front suspension rebuild this winter I really didn't have money for coilovers, well it was more of a choice of buy suspension or do lots of HPDE's. So I chose working on driver instead. I'm going to try R-comps for my next event in June, really wondering how that will work with soft stock springs, and dampers.

So Joe what would I need to to do to get into NASA TT. I just got promoted to HPDE4 with NASA and have been running BMWCCA advanced group for a while. By the way The HPDE4/instructor/TT run groups are nuts compared to BMWCCA. Its almost like your out there racing!

Yeah, 500/600 or 525/650, its all pretty similar and basically comes down to driver preference. Some guys run 450/650 on track which should be fine, but I would not recommend that for autox...too soft in front and the car will likely respond too slow and maybe want to overshoot the intended rotation.

R comps aren't something I generally would encourage. Now maybe you got a good deal on a used set and your street tires are done, thats fine. But at least for me, the only time I'll buy R comps is if I am competing in TT trying to win more R comps. Any time I do a non comp track day, its always on street tires. No changing tires at the track, bringing an extra set, and you get longer life. Not to mention passing everyone who is on R comps.
I would suggest getting a good suspension setup before buying new R comps. Getting max grip via proper suspension setup from a street tire is better than less than optimal setup running R comps. Plus you get more even wear on the tires.

Now in NASA MA HPDE4 is instructors only. If you want to get into TT, you just contact the TT coordinator and ask for a check ride, at which point they'll ride with you for a session and let you know if you are ready. They are really looking to see that you are safe, in control, and aware of other drivers around you. Last event our TT coordinator asked me to give a TT hopeful a check ride. He was dressed like the red Stig, drove a raced out E46 M3, and was way too wild and aggressive. We went off track twice, almost hit the tire wall once, scared me to death (I had already been in a crash earlier that morning). Needless to say....he didn't get the sign off.

TT is a lot of fun, and can be far cheaper than W2W racing. Check the classing before you go any further. I'm in TTC with suspension, R comps and aero. I'd rather be in TTD with just suspension and street tires. And take baby steps getting faster. There's no rush. Smoothness usually prevails.

Nope! But i m going to a test/tune day on saturday, and an autox on sunday.

And joe, thanks for the input! Im starting ot with the GC coilover kit. Well see how these do at my first event. I hope to use this event to learn the dynamics of the suspension and car. If i place down bottom, oh well.

I went with 525f/500R. Hopefully this will suit me well!

You should be off to a great start. Get some seat time with the car on the new suspension and a good alignment. Once you've driven it for a while, have a local fast driver try it and see if they have any comments (on the car and on your driving). It could help your driving and your setup, and let you decide if you want to make adjustments in the future. Good luck!

[das borgen]

TT is a lot of fun, and can be far cheaper than W2W racing. Check the classing before you go any further. I'm in TTC with suspension, R comps and aero. I'd rather be in TTD with just suspension and street tires. And take baby steps getting faster. There's no rush. Smoothness usually prevails.

extremely wise insight there

[CGS12]

Yeah, 500/600 or 525/650, its all pretty similar and basically comes down to driver preference. Some guys run 450/650 on track which should be fine, but I would not recommend that for autox...too soft in front and the car will likely respond too slow and maybe want to overshoot the intended rotation.

R comps aren't something I generally would encourage. Now maybe you got a good deal on a used set and your street tires are done, thats fine. But at least for me, the only time I'll buy R comps is if I am competing in TT trying to win more R comps. Any time I do a non comp track day, its always on street tires. No changing tires at the track, bringing an extra set, and you get longer life. Not to mention passing everyone who is on R comps.
I would suggest getting a good suspension setup before buying new R comps. Getting max grip via proper suspension setup from a street tire is better than less than optimal setup running R comps. Plus you get more even wear on the tires.

Now in NASA MA HPDE4 is instructors only. If you want to get into TT, you just contact the TT coordinator and ask for a check ride, at which point they'll ride with you for a session and let you know if you are ready. They are really looking to see that you are safe, in control, and aware of other drivers around you. Last event our TT coordinator asked me to give a TT hopeful a check ride. He was dressed like the red Stig, drove a raced out E46 M3, and was way too wild and aggressive. We went off track twice, almost hit the tire wall once, scared me to death (I had already been in a crash earlier that morning). Needless to say....he didn't get the sign off.

TT is a lot of fun, and can be far cheaper than W2W racing. Check the classing before you go any further. I'm in TTC with suspension, R comps and aero. I'd rather be in TTD with just suspension and street tires. And take baby steps getting faster. There's no rush. Smoothness usually prevails.

Yah I here you on the street tire thing. I love my Dunlop Dirrezza's, but after 15 or so track days they are shot. I picked up a set of 225/17/45 NT01's that have three track days on them for $250, so I'm going to run those until their shot. I'll then buy a new set of the Dunlops. Passing E46 M3's running R-comps and coilovers in a pretty much stock E36 M3 with 100K on the clock does give one a sense of accomplishment!

I currently have swapped strut hats, and the thickest Bimmerworld camber shim installed for 3.7 right and 3.4 degrees left front camber. I could only get
1.1 degrees of camber for the rear on either side. The car has no understeer now, but the back end of the car likes to rotate a bit and I know this is due to the lack of rear camber.

Now that you have gone to a higher rear spring rate how does you car handle on street tires?

[khaos]

Question: can this be done piece by piece? ie. springs with stock struts, then add konis, then plates and swaybar?

[PrinceE30]

Question: can this be done piece by piece? ie. springs with stock struts, then add konis, then plates and swaybar?

Start with camber plates. Even with soft, stock springs and shocks, they will do a world of good more than starting with springs and shocks. They should also make the most noticeable difference in actual maximum grip and handling properties. If you want to spend a little less, start with the big front bar like H&Rs. I'm finding the front bar to more and more useful to keep the rest of the car (ie. the rear) in check and prevent the car from tri-podding coming out of turns.

After the above, try to do springs and shocks at the same time. The only reason to do one and not the other is for something like SCCA stock class racing where you can change shocks (inserts, Ohlins SA OE replacement struts) but not springs.

1. Camber Plates
2. Front Bar
3. Springs and Shocks (get a good coil-over system - TRM, AST, TCKline, Koni, Bilstein, Moton)
4. Replace bushings while doing the above

On a related note, does anyone know the largest E36 front bar available? I found the Hotchkis @ 33.4mm tubular steel (300-380% stiffer than an M3 front bar). How does the H&R compare? Anyone know?

[scooper]

doesn't turner sell a 30mm front sway as well as GC? I believe next to the hotchkiss bars, the GC are the stiffest, but I have no proof of this.