Rear end stability for the 1m

[frenzy757]

Hey Everyone,

I tried searching and didn't find anything that was really recent (lots of really old posts).

I was wondering if over time, people were able to dial in the 1m to have better rear end stability (putting power down) out of turns etc.

If so what was the fix? LSD upgrade? tires (maybe except for r-comps)? Suspension? Wing?

Curious to see how the research and technology has advanced over the years for these cars!

[nachob]

Originally Posted by frenzy757

Hey Everyone,

I tried searching and didn't find anything that was really recent (lots of really old posts).

I was wondering if over time, people were able to dial in the 1m to have better rear end stability (putting power down) out of turns etc.

If so what was the fix? LSD upgrade? tires (maybe except for r-comps)? Suspension? Wing?

Curious to see how the research and technology has advanced over the years for these cars!

I have toyed with the idea of a softer rear bar and I believe Steve Dinan said he softened the suspension slightly on the 1M somewhere for better turn in and stability. I haven't actually done much though. I have found the the speed and pressure you apply to the gas pedal has a fairly direct correlation to the rear stepping out so I have decreased the rate and pressure to throttle application with pretty good success and it was a no cost modification.

I'm also intrigued like you if anyone has used an adjustable rear bar or softer suspension settings to keep the tires on the road. Thank you.

[JP-1M]

Originally Posted by nachob

...
I have found the the speed and pressure you apply to the gas pedal has a fairly direct correlation to the rear stepping out so I have decreased the rate and pressure to throttle application with pretty good success and it was a no cost modification.
...

What? Are you mad? I good car must be completely nannified with mechanical and electronic magic such that I can mash the gas pedal to the floor with steering at full lock and wet pavement and the car must still not spin its drive wheels. I expected you, of all people, nachob , to know better!

OP, my reply is a friendly jab at a forum vet, not a critique of your original question which I find relevant, but alas have no input into. I deliberately leave my 1M as close to stock as possible.

[frenzy757]

=) no worries.

My situation is that I am getting more into tracking. I had a 1m before. Sold it, got an S2000 and sold that all for the name of "Adult" things like home buying.

Now I have some funds and I want a car that I can track, get better at driving, and have the car scale with me.

I am leaning towards an e46 m3 (which I had in the past), but honestly, one of my favorite cars of all time is the 1m coupe. However, it was a bit twitchy (too much that I don't want to track it too much), but if I could dial it out somehow and have the car be great on track then I might take the plunge!

[10"]

Originally Posted by frenzy757

=) no worries.

My situation is that I am getting more into tracking. I had a 1m before. Sold it, got an S2000 and sold that all for the name of "Adult" things like home buying.

Now I have some funds and I want a car that I can track, get better at driving, and have the car scale with me.

I am leaning towards an e46 m3 (which I had in the past), but honestly, one of my favorite cars of all time is the 1m coupe. However, it was a bit twitchy (too much that I don't want to track it too much), but if I could dial it out somehow and have the car be great on track then I might take the plunge!

The more you drive it the better driver you become, in my opinion. Also the more you drive it the more predictable it becomes. Most of the people I've seen call the 1M twitchy haven't had a lot of seat time...

Take the plunge and sort it out later!

[Dackelone]

I think your best mod for quashing the rear oversteer coming out of the corners is a fresh set of tires. Some Michelin PSS or PS4S or Cup2's would probably be your best mod.

Btw... How old and tire model are you running? I hope not the original PS2's...

[The Wind Breezes]

If you want more rear end stability then loosen up the rear and tighten the front. Stiffer front anti roll is a easy bandaid. Putting a big camber differential between rear and front, with more in the rear, will also help vastly with stability although of course you will give up a little straight line accel grip which shouldn't matter unless you're on a autocross course or something. Camber mod would be my first suggestion. For serious high speed stability you would need to add rear downforce. The easiest way is a wing.

I will take a predictable car that understeers any day over a car with amazing turn in that's dangerous. 99.9% of drivers will end up being faster in the "slower" setup due to greater confidence and safety.

[10"]

Originally Posted by Dackelone

I think your best mod for quashing the rear oversteer coming out of the corners is a fresh set of tires. Some Michelin PSS or PS4S or Cup2's would probably be your best mod.

Btw... How old and tire model are you running? I hope not the original PS2's...

Great advice. PSS really sort out the car compared to PS2s. Far more predictable...

[godzilla-1]

My first mod was tyres. I fitted toyo R888's and have so much confidence in the car since doing that. Second mod was bilstein clubsport coilovers and a modest track/fast road wheel alignment setup. The result: Very confident consistent and predictable handling. Its still all about respecting your right foot though especially when you have 500 pounds of torque as a result of a few engine mods and a good remap.

[gmx]

Proper alignment and throttle mapping helped me the most. OEM throttle maps especially M-mode are too sensitive to control with the right foot. I would not use DSC off in conjunction with M-mode. This probably contributes to the twitchiness since the driver is requesting almost 80% torque/throttle when the physical pedal is only depressed 25% as an example.

To feel more connected but keep the OEM character, solid rear subframe mounts should be considered. Bilstein Clubsports are on the cards for me too.

To track this car, at a minimum you need camber plates and a decent tyre such as PSC2 or dedicated set. Then the standard check list; fluid/pads etc.
I insist you see the shortcomings of the suspension and then go from there. The front is too soft and under threshold and trail-braking can lead to the rear floating around as the front strut cannot resist load transfer. An alignment will help here but you will still feel it. Pushing this car and braking to the apex has given me an armful of lock a handful of times, but I'm also not a pro.

I started slow and am happy with my journey although I knew it would lead me down this path eventually. Overall, I've enjoyed it a lot and look forward to more.
Beware, this car will not set blistering laptimes and probably won't even with equal development to say, an E92 M3 - it's just not about that and never was since it's conception.

[M3 Adjuster]

Originally Posted by 10"

Great advice. PSS really sort out the car compared to PS2s. Far more predictable...

and now P4s is another leap..

Originally Posted by 10"

The more you drive it the better driver you become, in my opinion. Also the more you drive it the more predictable it becomes. Most of the people I've seen call the 1M twitchy haven't had a lot of seat time...

Take the plunge and sort it out later!

+1 I have found that suddenly I have become a lot more confident in the chassis in the last year or two.

Camber plates for the front are a neccessory.
Wider than OEM rear tires help with getting the power down and rear end stability

As far as being an ideal track car... If you are getting a car for it's primary purpose to be a track car then an E46 is a better option with lower running costs and potentially better performance depending on how far you go with the mods.

[searchdev]

Hi there, this is my first post so be gentle :-)

I track my 1M exclusively. I have about 30 track days at tracks such as Mosport, Watkins Glen and Mont Tremblant.

My car, up until last week, was stock. My philosophy is to get 100% out of the stock car before doing upgrades.

So I completely agree with you about the behaviour of the rear-end. I come from a Z4 M Coupe, which is a very well mannered car so the 1M felt like a wild bull.

On the street, good tires make a bit of difference but with a short wheel base and a lot of torque, the car will feel uncomfortable when pressed.

My comments relate more to the track. The Pilot Sports are not a track tire so upgrading to PSS's or P4S's is a great move. When you get to the limits of them you can upgrade to RE71R's or RS4's.

The single biggest thing that I did to stabilize the car on the track is the M
button. I find that with it off, the turbo spools up when I am accelerating out of the corners. Where I am with my speed, 4th gear and the revs, the turbo punches me in the back and makes the car unstable. By using the M button, the power comes on smoother. Many will say that the M button makes it more twitchy but for me, when the waste gates are closed, the turbos provide smooth power. It took me a year before I pressed the M button and I had many very uncomfortable moments before I did.

So caveat is, you need to be smooth with the throttle. That is good practice in any car. Use it like a light switch and you will have twitchy issues regardless.

From my experience, the 1M is a very fast track car. I am doing great lap times which keep up with good drivers in e92 M3's. You have to work at it and it takes time but this car does fly.

For interest sake, i just installed MCS 1-way suspension with Vorshlag camber plates. I am also now running a square set up of 275's Nitto NT01's. My comments above are about stock with a good tire.

I hope this helps in a small way. Enjoy the car on the track. Drive safe!

[CarJunkie]

I did camber plates and stiffer FSB at the same time, so it is hard to evaluate toe contributions of each. It seems to me that addressing the understeer on corner entry really helps with corner exit. Camber up front does that really well, and the car wants to rotate. The throttle is used to settle the car rather than to induce oversteer which I found myself doing before the mods. Coilovers added much better feel and control, but the balance of the car was transformed by giving the front end more camber than the rear. As counter-intuitive as it seems, I found that inceasing front grip relative to the rear truly settled the rear.

[Dackelone]

Originally Posted by searchdev

Hi there, this is my first post so be gentle :-)

I track my 1M exclusively. I have about 30 track days at tracks such as Mosport, Watkins Glen and Mont Tremblant.

My car, up until last week, was stock. My philosophy is to get 100% out of the stock car before doing upgrades.

So I completely agree with you about the behaviour or the rear-end. I come from a Z4 M Coupe, which is a very well mannered car so the 1M felt like a wild bull.

On the street, good tires make a bit of difference but with a short wheel base and a lot of torque, the car will feel uncomfortable when pressed.

My comments relate more to the track. The Pilot Sports are not a track tire so upgrading to PSS's or P4S's is a great move. When you get to the limits of them you can upgrade to RE71R's or RS4's.

The single biggest thing that I did to stabilize the car on the track is the M
button. I find that with it off, the turbo spools up when I am accelerating out of the corners. Where I am with my speed, 4th gear and the revs, the turbo punches me in the back and makes the car unstable. By using the M button, the power comes on smoother. Many will say that the M button makes it more twitchy but for me, when the waste gates are closed, the turbos provide smooth power. It took me a year before I pressed the M button and I had many very uncomfortable moments before I did.

So caveat is, you need to be smooth with the throttle. That is good practice in any car. Use it like a light switch and you will have twitchy issues regardless.

From my experience, the 1M is a very fast track car. I am doing great lap times which keep up with good drivers in e92 M3's. You have to work at it and it takes time but this car does fly.

For interest sake, i just installed MCS 1-way suspension with Vorshlag camber plates. I am also now running a square set up of 275's Nitto NT01's. My comments above are about stock with a good tire.

I hope this helps in a small way. Enjoy the car on the track. Drive safe!

Since you are tracking your 1M so much... perhaps consider installed an Accusump made by Canton. It will provide oil pressure in critical conditions such as hard cornering or hard braking... when the engine can run without enough oil pressure. For track cars this can mean the difference between an engine overhaul or not.

www.accusump.com


I would also be changing your fluids after each track event, like brake, oil, diff, trans fluids. Well... maybe diff and trans you could go a few events before changing... but engine oil and brake fluid changes are a must.

As for tires why aren't you running Michelin Cup2 tires ? I also assume you aren't running stock brake pads or brake lines ?

M3 Adjuster Maybe you can post that video of your 1M coming out of a corner and spinning or almost spinning off, from a few years ago...

Dackel

[gmx]

Originally Posted by CarJunkie

I did camber plates and stiffer FSB at the same time, so it is hard to evaluate toe contributions of each. It seems to me that addressing the understeer on corner entry really helps with corner exit. Camber up front does that really well, and the car wants to rotate. The throttle is used to settle the car rather than to induce oversteer which I found myself doing before the mods. Coilovers added much better feel and control, but the balance of the car was transformed by giving the front end more camber than the rear. As counter-intuitive as it seems, I found that inceasing front grip relative to the rear truly settled the rear.

I'm actually the opposite. Balance wise, it understeers and is front-limited despite maxed front camber on otherwise OEM suspension. I do not abide by "throttle steering", imo that is just bad practice and not the quickest way. It will also bite you in this car.
My experience is with stock fitment in 19" with Cup2s in OEM fitment tyres; 245 front and 265 rear.
I actually find the car really stable in fast corners due to this, which is simply more speed to be unlocked.

Ultimately by next season, I will aim for:
Bilstein CS 2 ways
18x10 with 275 square
Solid rear subframe mounts

Then proceed from there after evaluating it.

[searchdev]

Thanks for the reply Dackel.

I will look into Accusump. Thanks for the suggestion.

I change my fluids regularly. Probably too often but I would rather be safe than sorry.

I find the PS2's really expensive. I got the NT01's used on a set of used Apex wheels. They have a track day or two left. I will then go to RS4's. I hear the grip is slightly less then the RE71R's but they don't wear as fast. My tire of choice has been the RE71R's but with a stock set up I have only been able to get about 4 track days on them when I am pushing the car. With the new set-up I should be able to get better life from my tires. Camber alone should give me a few more days.

I am at the track next week and eager to feel how the car handles with a proper track set-up.

[ayao]

Originally Posted by searchdev

Hi there, this is my first post so be gentle :-)

I track my 1M exclusively. I have about 30 track days at tracks such as Mosport, Watkins Glen and Mont Tremblant.

My car, up until last week, was stock. My philosophy is to get 100% out of the stock car before doing upgrades.

So I completely agree with you about the behaviour of the rear-end. I come from a Z4 M Coupe, which is a very well mannered car so the 1M felt like a wild bull.

On the street, good tires make a bit of difference but with a short wheel base and a lot of torque, the car will feel uncomfortable when pressed.

My comments relate more to the track. The Pilot Sports are not a track tire so upgrading to PSS's or P4S's is a great move. When you get to the limits of them you can upgrade to RE71R's or RS4's.

The single biggest thing that I did to stabilize the car on the track is the M
button. I find that with it off, the turbo spools up when I am accelerating out of the corners. Where I am with my speed, 4th gear and the revs, the turbo punches me in the back and makes the car unstable. By using the M button, the power comes on smoother. Many will say that the M button makes it more twitchy but for me, when the waste gates are closed, the turbos provide smooth power. It took me a year before I pressed the M button and I had many very uncomfortable moments before I did.

So caveat is, you need to be smooth with the throttle. That is good practice in any car. Use it like a light switch and you will have twitchy issues regardless.

From my experience, the 1M is a very fast track car. I am doing great lap times which keep up with good drivers in e92 M3's. You have to work at it and it takes time but this car does fly.

For interest sake, i just installed MCS 1-way suspension with Vorshlag camber plates. I am also now running a square set up of 275's Nitto NT01's. My comments above are about stock with a good tire.

I hope this helps in a small way. Enjoy the car on the track. Drive safe!

This is an interesting thought that I’ve never considered. The M button makes the throttle even harder to modulate on the street but on track I can see how altered wastegate mapping might be beneficial.

[M3 Adjuster]

Originally Posted by searchdev

Thanks for the reply Dackel.

I will look into Accusump. Thanks for the suggestion.

I change my fluids regularly. Probably too often but I would rather be safe than sorry.

I find the PS2's really expensive. I got the NT01's used on a set of used Apex wheels. They have a track day or two left. I will then go to RS4's. I hear the grip is slightly less then the RE71R's but they don't wear as fast. My tire of choice has been the RE71R's but with a stock set up I have only been able to get about 4 track days on them when I am pushing the car. With the new set-up I should be able to get better life from my tires. Camber alone should give me a few more days.

I am at the track next week and eager to feel how the car handles with a proper track set-up.

One simply cannot afford to track a 1M without camber plates. 4 track days on the stock setup means around $250 a day for a tire expense which is obviously not sustainable.



Camber plates are the single greatest mod for the 1M. A set of camber plates is $600 and will more than double the life of any tire on the front end, and you don't even need to do anything else.

Look forward to hearing your comments after the camber plate/ suspension install.

With regards to the M button.. I have found I don't like it in most situations.

I tried doing runs in autocross with it on and off. With the M button on , the hyper sensitive throttle simply made fine adjustments of the throttle more difficult and cost me time particularly in slaloms . I was hoping that keeping the wastegate closed and turbos spooled would make a difference but they didn't.

Using the M button on track does make a lot of sense. I've noticed that in long sessions on track I don't mind the more sensitive throttle input and I get used to it and one of course there is lots of time at WOT. Keeping the turbos spooled up to come out of a corner down a straight has a clear advantage.

Sadly I use it so little that i typically don't turn in on every session. I'll try and use it a bit more perhaps but I've gotten really comfortable with the stock mapping.

On the street I prefer the M button OFF. I sometimes switch it on if I want to do a fun cloverleaf.

[JP-1M]

searchdev
M3 Adjuster

What you are both saying about the M button and its effect on the wastegates is a revalation. To date the only trustworthy info I have seen is indicating it only changes throttle mapping.

I’ll wander off to Google and start searching myself, but do either of you have a link to any information documenting this behavior?

[ayao]

Originally Posted by JP-1M

searchdev


What you are both saying about the M button and its effect on the wastegates is a revalation. To date the only trustworthy info I have seen is indicating it only changes throttle mapping.

I’ll wander off to Google and start searching myself, but do either of you have a link to any information documenting this behavior?

https://www.1addicts.com/forums/showthread.php?t=866565