Has anyone done a full m3 conversion?

[Zombie1]

http://hpashop.com/BMW-E8X-E9X-to-M3...conversion.htm has anyone done the whole kit, if so what's the review?

[fboutlaw]

Originally Posted by Zombie1

http://hpashop.com/BMW-E8X-E9X-to-M3...conversion.htm has anyone done the whole kit, if so what's the review?

Done everything except for the rear lower link. That part requires you to change springs / struts, which I had done prior to swapping all the components.

Verdict: it's an amazing transformation. The e82 stock (non M) has a very soft suspension and play between every component in the suspension. Normally you'd get that play in all direction from your tires, but with run flats, they are so stiff you get little play. Thus the suspension has to take care of the compliance in our cars. If you switch to non-RFT, you will immediately notice that the car feels sloppy, which is because you've added a mode of travel to your car in all directions (x, y, and z), which are not tuned to match.

M3 / 1M cars are built for normal tires. They assume the suspension should provide the proper travel for your wheels, but the tires will take care of the comfort aspect. The parts are lighter and have better joints between all parts.

Now as a review, I did everything in stages, so I'll go stage by stage:

1. Strut tower bar
- This does nothing over stock parts. Only install if you need access to the top of your struts (certain adjustable shocks adjust at the top).

2. Front roll bar
- Limited roll side to side significantly over stock. Less understeer through corners. Car still very sloppy, hard to settle into a corner.

3. Rear subframe bushings, Rear roll bar
- Subframe bushings helped the subframe feel connected to the chassis. Before it felt like the rear wheels were floating under the car in all directions. Less roll in the rear of the car. Now you could feel the rear of the car, but honestly with the rear roll bar, it felt too stiff. I now had to be more careful into corners, and watch my corner speed, resulting in countless autox spins. The rear was now connected to the ground and the sloppiness of my driving was very apparent.

4. Front tension rod + wishbones
- Huge difference. You can now feel the road surface through your steering wheel. The added camber of the wishbones also adds to corner grip.

5. Rear guide rods + upper arms
- Huge difference. The rear of the car now really feels connected. I can push the car through corners and not have the rear tires flexing in unpredictable ways, letting me get into corner slides without feeling out of control (like before). Able to be very accurate with the throttle as it translates directly to the ground rather than building up stored energy in the suspension.

6. Rear toe arm
- Haven't installed yet. Sitting in my garage until my next alignment. I expect this will make the suspension react faster as it's way lighter than the stock part, but I'm honestly a bit sketched out the the adjustable arm instead of a forged aluminum part. We'll see next season.

So overall. If you're going to do it, do all you can. Leave out the rear camber link kit unless you are doing coilovers. And leave out the strut tower brace unless you need access to an adjustable pin at the top of your front shocks.

Once you're done, expect a better car. I just crossed 30k miles this weekend and the car is far superior now than it was at mile 0.

[Dackelone]

Originally Posted by fboutlaw

Done everything except for the rear lower link...

You also did not change your tie rods to M3 units.

[Zombie1]

Originally Posted by fboutlaw

Done everything except for the rear lower link. That part requires you to change springs / struts, which I had done prior to swapping all the components.

Verdict: it's an amazing transformation. The e82 stock (non M) has a very soft suspension and play between every component in the suspension. Normally you'd get that play in all direction from your tires, but with run flats, they are so stiff you get little play. Thus the suspension has to take care of the compliance in our cars. If you switch to non-RFT, you will immediately notice that the car feels sloppy, which is because you've added a mode of travel to your car in all directions (x, y, and z), which are not tuned to match.

M3 / 1M cars are built for normal tires. They assume the suspension should provide the proper travel for your wheels, but the tires will take care of the comfort aspect. The parts are lighter and have better joints between all parts.

Now as a review, I did everything in stages, so I'll go stage by stage:

1. Strut tower bar
- This does nothing over stock parts. Only install if you need access to the top of your struts (certain adjustable shocks adjust at the top).

2. Front roll bar
- Limited roll side to side significantly over stock. Less understeer through corners. Car still very sloppy, hard to settle into a corner.

3. Rear subframe bushings, Rear roll bar
- Subframe bushings helped the subframe feel connected to the chassis. Before it felt like the rear wheels were floating under the car in all directions. Less roll in the rear of the car. Now you could feel the rear of the car, but honestly with the rear roll bar, it felt too stiff. I now had to be more careful into corners, and watch my corner speed, resulting in countless autox spins. The rear was now connected to the ground and the sloppiness of my driving was very apparent.

4. Front tension rod + wishbones
- Huge difference. You can now feel the road surface through your steering wheel. The added camber of the wishbones also adds to corner grip.

5. Rear guide rods + upper arms
- Huge difference. The rear of the car now really feels connected. I can push the car through corners and not have the rear tires flexing in unpredictable ways, letting me get into corner slides without feeling out of control (like before). Able to be very accurate with the throttle as it translates directly to the ground rather than building up stored energy in the suspension.

6. Rear toe arm
- Haven't installed yet. Sitting in my garage until my next alignment. I expect this will make the suspension react faster as it's way lighter than the stock part, but I'm honestly a bit sketched out the the adjustable arm instead of a forged aluminum part. We'll see next season.

So overall. If you're going to do it, do all you can. Leave out the rear camber link kit unless you are doing coilovers. And leave out the strut tower brace unless you need access to an adjustable pin at the top of your front shocks.

Once you're done, expect a better car. I just crossed 30k miles this weekend and the car is far superior now than it was at mile 0.

thanks very useful review

[Sleeps]

Originally Posted by fboutlaw

Done everything except for the rear lower link. That part requires you to change springs / struts, which I had done prior to swapping all the components.

Verdict: it's an amazing transformation. The e82 stock (non M) has a very soft suspension and play between every component in the suspension. Normally you'd get that play in all direction from your tires, but with run flats, they are so stiff you get little play. Thus the suspension has to take care of the compliance in our cars. If you switch to non-RFT, you will immediately notice that the car feels sloppy, which is because you've added a mode of travel to your car in all directions (x, y, and z), which are not tuned to match.

M3 / 1M cars are built for normal tires. They assume the suspension should provide the proper travel for your wheels, but the tires will take care of the comfort aspect. The parts are lighter and have better joints between all parts.

Now as a review, I did everything in stages, so I'll go stage by stage:

1. Strut tower bar
- This does nothing over stock parts. Only install if you need access to the top of your struts (certain adjustable shocks adjust at the top).

2. Front roll bar
- Limited roll side to side significantly over stock. Less understeer through corners. Car still very sloppy, hard to settle into a corner.

3. Rear subframe bushings, Rear roll bar
- Subframe bushings helped the subframe feel connected to the chassis. Before it felt like the rear wheels were floating under the car in all directions. Less roll in the rear of the car. Now you could feel the rear of the car, but honestly with the rear roll bar, it felt too stiff. I now had to be more careful into corners, and watch my corner speed, resulting in countless autox spins. The rear was now connected to the ground and the sloppiness of my driving was very apparent.

4. Front tension rod + wishbones
- Huge difference. You can now feel the road surface through your steering wheel. The added camber of the wishbones also adds to corner grip.

5. Rear guide rods + upper arms
- Huge difference. The rear of the car now really feels connected. I can push the car through corners and not have the rear tires flexing in unpredictable ways, letting me get into corner slides without feeling out of control (like before). Able to be very accurate with the throttle as it translates directly to the ground rather than building up stored energy in the suspension.

6. Rear toe arm
- Haven't installed yet. Sitting in my garage until my next alignment. I expect this will make the suspension react faster as it's way lighter than the stock part, but I'm honestly a bit sketched out the the adjustable arm instead of a forged aluminum part. We'll see next season.

So overall. If you're going to do it, do all you can. Leave out the rear camber link kit unless you are doing coilovers. And leave out the strut tower brace unless you need access to an adjustable pin at the top of your front shocks.

Once you're done, expect a better car. I just crossed 30k miles this weekend and the car is far superior now than it was at mile 0.

Is there a parts list for all the possible M3 suspension bits that you can use on the 135 or that is recommended. Would love to know exactly what you used. This is a great write up by the way, thank you!

[fboutlaw]

Originally Posted by Flew The

Is there a parts list for all the possible M3 suspension bits that you can use on the 135 or that is recommended. Would love to know exactly what you used. This is a great write up by the way, thank you!

You can get just about everything at HPA (link from OP), ECS Tuning, or getbmwparts.com

Here's how I went.
HPA: strut tower brace, front wishbones, front tension rods, F/R sway bars, Rear toe adjuster, subframe bushings + bushing tool rental
ECS Tuning: Rear upper link, rear guide rods

One really nice thing about ECS is that they provide new hardware (bolts/nuts) for when you are changing links.

One really great thing about HPA is that you can rent a bushing puller and replacement kit. It's a hard job and I can't imagine doing it without the proper tools.

If you have questions about which part will fit, just look for what BMW used on the e82 M coupe at www.realoem.com.

[lastMleft]

Originally Posted by fboutlaw

Done everything except for the rear lower link. That part requires you to change springs / struts, which I had done prior to swapping all the components.

Verdict: it's an amazing transformation. The e82 stock (non M) has a very soft suspension and play between every component in the suspension. Normally you'd get that play in all direction from your tires, but with run flats, they are so stiff you get little play. Thus the suspension has to take care of the compliance in our cars. If you switch to non-RFT, you will immediately notice that the car feels sloppy, which is because you've added a mode of travel to your car in all directions (x, y, and z), which are not tuned to match.

M3 / 1M cars are built for normal tires. They assume the suspension should provide the proper travel for your wheels, but the tires will take care of the comfort aspect. The parts are lighter and have better joints between all parts.

Now as a review, I did everything in stages, so I'll go stage by stage:

1. Strut tower bar
- This does nothing over stock parts. Only install if you need access to the top of your struts (certain adjustable shocks adjust at the top).

2. Front roll bar
- Limited roll side to side significantly over stock. Less understeer through corners. Car still very sloppy, hard to settle into a corner.

3. Rear subframe bushings, Rear roll bar
- Subframe bushings helped the subframe feel connected to the chassis. Before it felt like the rear wheels were floating under the car in all directions. Less roll in the rear of the car. Now you could feel the rear of the car, but honestly with the rear roll bar, it felt too stiff. I now had to be more careful into corners, and watch my corner speed, resulting in countless autox spins. The rear was now connected to the ground and the sloppiness of my driving was very apparent.

4. Front tension rod + wishbones
- Huge difference. You can now feel the road surface through your steering wheel. The added camber of the wishbones also adds to corner grip.

5. Rear guide rods + upper arms
- Huge difference. The rear of the car now really feels connected. I can push the car through corners and not have the rear tires flexing in unpredictable ways, letting me get into corner slides without feeling out of control (like before). Able to be very accurate with the throttle as it translates directly to the ground rather than building up stored energy in the suspension.

6. Rear toe arm
- Haven't installed yet. Sitting in my garage until my next alignment. I expect this will make the suspension react faster as it's way lighter than the stock part, but I'm honestly a bit sketched out the the adjustable arm instead of a forged aluminum part. We'll see next season.

So overall. If you're going to do it, do all you can. Leave out the rear camber link kit unless you are doing coilovers. And leave out the strut tower brace unless you need access to an adjustable pin at the top of your front shocks.

Once you're done, expect a better car. I just crossed 30k miles this weekend and the car is far superior now than it was at mile 0.

What's the cost for all these parts ^^^^?

[flinchy]

Originally Posted by Rukuss

What's the cost for all these parts ^^^^?

$500-600 for the front tension rod and control arm (wishbone)

$250 for rear sub frame bushings (plus half a days labour)

$500(?) for front and rear sway bars

Most kits/parts seem to float around the $500 mark

Strut brace is $200-$250 for aluminium straight bar, $500ish for an m3 one (not worth it imo, WAY too exxy and eh not a fan), $500+ for a carbon fiber one (lighter stiffer an prettier hah)

[Southjersey128]

Just took my rear sub frame out tonight. Doing the bushings and e92 sway bar tomorrow morning. Dropping the sub frame was easier than I thought, took about an hour.(keep in mind I'm a certified tech with 13 years experience, using a tranny jack and lift. ) I suspect getting the bushings out and in is going to be the hard part, I did not get the tool from hpa. I think I'll cut the old ones out and use a ball joint press to get the new ones in. No need to save the old ones. Next up will be the control arms and rods for the front. That's a few months away though. Thanks for the detailed post, let's me know where I'll stand after each stage!
Installed the bushings and sway bar this morning. If your thinking of not renting the tool I would highly recommend you re think it. Took me an hour to throw together a makeshift install tool. After I got the sub frame back in the car and drove it, it was just as post described. Sharp in the rear, seems like it took out a lot of under steer also. The e92 bar does seem a little too stiff but with just the power of the 128 it is way easier to control than the 135 I would presume. Makes it real fun to drive and much more comfortable too. Thanks again for the spot on post.

[int2str]

Originally Posted by fboutlaw

1. Strut tower bar
- This does nothing over stock parts. Only install if you need access to the top of your struts (certain adjustable shocks adjust at the top).

Very informative post. One minor correction/addition on this point:
The M/// strut tower brace is adjustable and can give you additional negative camber or help move the shock tops more into the center of the opening.

[fboutlaw]

Originally Posted by int2str

Very informative post. One minor correction/addition on this point:
The M/// strut tower brace is adjustable and can give you additional negative camber or help move the shock tops more into the center of the opening.

This is bull. I want to post an annoyed picard here!

How? Does it expand the through thru holes for the bolts through the top of the strut tower? You can move your stock suspension over to the end of the thru holes without the tower. The adjustability in the arms is just to get it to fit, not to control camber.

[int2str]

Originally Posted by fboutlaw

This is bull. I want to post an annoyed picard here!

Honestly, I thought so too at first. But it does!

How? Does it expand the through thru holes for the bolts through the top of the strut tower?

The sad truth is that the chassis/shock towers without a brace can actually move in/out. So the adjustment is not the relative position of the shock to the tower, but the two towers to each other.

The M3/1M bar has elongated slots which allow you to make the bar longer (push the towers apart = less camber) or make the bar shorter (pull the towers together = more camber).

I found this out the hard way, btw. and have 100% proof. Camber on my car with my TC Kline camber plates fully maxed (shock adjusters touching painted metal of the car in the cut-out) was -3.1 degrees. After swapping the stock bar to the M3 bar with the car sitting on the ground, the car had nearly -4 degrees of camber (-3.8 to be picky). Now I have the car dialed to -2.8 degrees and I can comfortably adjust the shocks now nice the adjuster is no longer touching the painted metal.

I talked this over with a local autocross instructor and he confirmed that the slots are for camber adjustability.

[fboutlaw]

Originally Posted by int2str

The M3/1M bar has elongated slots which allow you to make the bar longer (push the towers apart = less camber) or make the bar shorter (pull the towers together = more camber).

I found this out the hard way, btw. and have 100% proof. Camber on my car with my TC Kline camber plates fully maxed (shock adjusters touching painted metal of the car in the cut-out) was -3.1 degrees. After swapping the stock bar to the M3 bar with the car sitting on the ground, the car had nearly -4 degrees of camber (-3.8 to be picky). Now I have the car dialed to -2.8 degrees and I can comfortably adjust the shocks now nice the adjuster is no longer touching the painted metal.

I talked this over with a local autocross instructor and he confirmed that the slots are for camber adjustability.

I dislike flame wars, but sir, you are generally incorrect.

With camber plates, there are two levels of adjustability.
1. The camber plate itself
2. Where your bolts sit when they come through the strut tower

Because you have to unbolt the three bolts when you adjust camber, it's very easy to adjust BOTH at the same time without knowing it, making your camber plates unreliable as reference measurements unless you mark the bolt position to the frame. Most likely that's the adjustment you're seeing. It's not the towers varying by inches.

More importantly, if your statement was factual, you have clearly invented a new metallic compound for your ground control camber plate thru bolts. Their torque settings are probably 19lb ft. They're honestly not that strong and are made to be able to shear in a collision. You've somehow mitigated that shear and are pushing the car apart using them. Quite frankly, you should patent your new material.

The correct way to install the towers and adjust camber to prevent the shear is to:
1. Take the airbox assembly out.
2. Loosen the adjustments on the strut tower brace
3. Jack up the car
4. Loosen the three top nuts on your strut
5. Make your adjustments to the strut alignment
6. With the M3 strut tower brace loose, torque the top nuts down to 19 lb ft (camber plates), 25 lb ft with no camber plates
7. Put the car back down
8. Torque the bolts on the strut tower brace based on the resting position they are at when the car is at rest.
9. Other side
10. replace airbox

The adjustment is to account for manufacturing tolerances in the car and secondly to allow you to move the 3 top bolts in their channels and still have the thing fit in the car.

Sorry, but my BSME, MSME, and years of experience in mechanical and systems engineering prevent me from allowing this on the forums. Your installer was right. They allow for camber adjustability, but you misunderstood him. The camber adjustment is done at the top of the tower. The strut bar allows for some range in camber, but it does not make it, nor does it have any bearing on your final settings.

[int2str]

Originally Posted by fboutlaw

I dislike flame wars, but sir, you are generally incorrect.

Fair enough. I don't mind a good argument at all. Nor do I mind being wrong .

Most likely that's the adjustment you're seeing. It's not the towers varying by inches.

Unlikely given previous attempts to max out camber that way - but possible.
Also I'm not talking inches, but mm....

More importantly, if your statement was factual, you have clearly invented a new metallic compound for your ground control camber plate thru bolts. Their torque settings are probably 19lb ft. They're honestly not that strong and are made to be able to shear in a collision. You've somehow mitigated that shear and are pushing the car apart using them.

That's a pretty good argument. Though the torque setting not being directly related to the shear strength. Assuming a shear strength of 500lbs per bolt (not unrealistic, I'd say), it's 1500lbs per side which is not so bad .

Also, if you're saying that in no way does the brace affect the distance of the top shock towers in relation to each other. Than you're in effect saying that no bar is needed in the first place. And that the chassis rigidity would prevent any relative movement of the shock towers at all.
Am I to understand you correctly?

Sorry, but my BSME, MSME, and years of experience in mechanical and systems engineering prevent me from allowing this on the forums.

...
it does not make it, nor does it have any bearing on your final settings.[/QUOTE]

Again, very much value your input on this and I'm not going to claim to be an expert here. That does not distract from the fact that it actually did make a difference for me.

I am very happy concede to be wrong on this one though. Just need a little more convincing

[Inconspicuous]

A reasoned debate between intelligent, technically literate participants that hasn't devolved into ad hominem attacks and is on its way to producing useful, reliable conclusions? If I'm dreaming this, don't wake me up.

BTW, fboutlaw, thanks for that detailed and informative breakdown of the M3 bits. Probably the most thorough analysis of their impact that I've read yet, and a post I will undoubtedly revisit when I tackle my own suspension.

[daixloxbmw]

Originally Posted by Inconspicuous

A reasoned debate between intelligent, technically literate participants that hasn't devolved into ad hominem attacks and is on its way to producing useful, reliable conclusions? If I'm dreaming this, don't wake me up.

BTW, fboutlaw, thanks for that detailed and informative breakdown of the M3 bits. Probably the most thorough analysis of their impact that I've read yet, and a post I will undoubtedly revisit when I tackle my own suspension.

+1000!!!

[fboutlaw]

Originally Posted by int2str

Fair enough. I don't mind a good argument at all. Nor do I mind being wrong .

Glad we cleared that up.

But there are a couple parts that I was unclear on.

- At rest, there is no impact with the strut tower bar. It should be installed so that there is zero force exerted on the system in any location.

- The purpose of having the strut tower bar is to limit movement under loads. In a corner, you support the entire weight of the car plus the acceleration (F=ma) of the roll through the springs which translate force into the frame. Instead of that force coming into sheet metal of the frame, the bar takes the force and braces against the firewall in the center of the car. That way you get the stiffness of the sheet metal plus a brace against the firewall. The brace limits how much the tower top can move under load, and will help to maintain the geometries you selected at rest rather than have a huge variance in corners making them unpredictable.

- Alignments and adjustments should be measured with the car solidly on the ground under loading specified by BMW. As the strut bar is taking no load at this state, it does not play into the alignment (camber) if done properly.

- Most cars to not have strut bars. Most people don't like to drive hard and would prefer a cheaper car and this is one extra part. It's not needed if you don't care about preserving geometries under load.

Continued Review

To continue my review in my OP of this thread. I just got the rear toe arms in this weekend from Rogue Engineering. Predictably, they once again bring better connectedness to the rear of the car by taking out the awful rubber bushings the e82 non-M has.

However, I would not recommend them unless your car is severely dropped to the point where your alignment shop complains that they cannot align your wheels. The eccentric bolts provide more than enough range unless your car is slammed to the ground.

Recommendation: Get M variants from ECS or Silver Springs BMW. It's much better to have a solid aluminum forging than an adjustable tube just to limit moving parts. I'm scared the joint may come loose during driving, but have little basis here except that it's hard to get to the nuts to get them tight when the link is on your car.

[ShocknAwe]

Excellent posts thank you. Can anyone comment on the recommended order of install assuming this would be done in stages to a car on stock m-sport ride height?

[fboutlaw]

Originally Posted by ShocknAwe

Excellent posts thank you. Can anyone comment on the recommended order of install assuming this would be done in stages to a car on stock m-sport ride height?

Assuming you're not changing springs / struts or putting in an LSD:

1. Front install
- Front E92 Sway
- Wishbones
- Control Arms
2. Rear install
- Rear upper links (both)
- Subframe bushing swap
- (Optional) Dinan rear sway bar
3. (Optional) Extras
- (Optional) M3 Rear toe arm
- (Optional) Front strut brace
- (Optional) Spring / strut package or coilovers

Doing all front or rear suspension at one time is a huge time saver and cost if you're having a garage do it. The rear is a huge pain to do. Swapping bushings requires dropping the rear subframe and disconnecting the drive shaft. Once it's down, it's real easy to work on and get everything done in one shot. You really don't want to repeat this operation if you can avoid it.

The front is more important that the rear in our car so that you get the sway bar in there to limit understeer. The e82 loves plowing through corners, so this will keep you more set and give you a little camber for added corner grip from the wishbones.

After the front is done, the major thing to do in the rear is the subframe bushings. The rest is nice to have.

[1Pirate]

I have all the front M3 suspension pieces, including an M3 E93 FSB. My car also has Koni sport dampers and non runflat tires. Next I'm considering doing some of the rear suspension upgrades in stages. I'm thinking about doing the rear guide rods and upper control arms first. After that the rear subframe bushings and maybe the rear upper link kit.

What do those of you who have done these mods think about the sequence of the mods and/or the benefit of those mods? I know that the rear subframe bushings are generally considered one of the best mods to the rear suspension, but I'm not as sure about the other mods.

[fboutlaw]

Originally Posted by 1Pirate

What do those of you who have done these mods think about the sequence of the mods and/or the benefit of those mods? I know that the rear subframe bushings are generally considered one of the best mods to the rear suspension, but I'm not as sure about the other mods.

[1Pirate]

Originally Posted by fboutlaw

I have read the thread. Several times in fact. Not everyone has followed the same steps nor done the same mods in the same order.

In my opinion the front M3 suspension mods are a no brainer. The rear mods I'm less certain about. If you read my post you saw that I'm asking about the rear guide rods and upper control arms and whether whether they are worth doing and whether doing them before the rear subframe bushings is the way to go. I know you did the subframe bushings first.

As I said not everyone has the same opinion nor has everyone followed the same steps. For example in your first post you mentioned that one of your stages was to install the rear guide rods and upper controls arms. However, in a subsequent post you only mentioned the rear subframe bushings and rear upper links (which you didn't mention in your first post) when you were discussing which rear M3 parts to install.