got money, LSD or suspension upgrade?

[vampire81]

dear folks,

after doing engine mods (DP/FMIC/JB4) it is now time for suspension work. car is 2013 135i M sport package, DCT.

this is my weekend toy, spirited driving. would like to upgrade the suspension, have more grip when cornering but not sacrificing ride quality.
i will be taking the car 2-3 times a year to the track.

the crappy RFTs but will change soon to Michelin PS2 and do a 225-255 front-rear.

got $2500 to spend. should i save more and get a LSD or upgrade the suspension, and what to upgrade specifically!

thanks for your help,

[worries]

Originally Posted by vampire81

dear folks,

after doing engine mods (DP/FMIC/JB4) it is now time for suspension work. car is 2013 135i M sport package, DCT.

this is my weekend toy, spirited driving. would like to upgrade the suspension, have more grip when cornering but not sacrificing ride quality.
i will be taking the car 2-3 times a year to the track.

the crappy RFTs but will change soon to Michelin PS2 and do a 225-255 front-rear.

got $2500 to spend. should i save more and get a LSD or upgrade the suspension, and what to upgrade specifically!

thanks for your help,

M3 front control arms made a pretty big difference in handling for me, adds some negative camber to the front also. I went with coilovers and I like the stiffer suspension and better looking ride height. Next up is getting rid of the runflats and getting some wider wheels, that should also make a huge difference in handling. After that is rear M3 bushings but I'm considering doing the LSD upgrade as well because the subframe needs to be dropped for both.

I tried to go with the most bang for the buck. M3 front parts were $300ish I think, and coilovers $1000ish. I would have ditched the run flats first but it's hard to justify getting rid of brand new tires so soon, maybe in 6 months or so I'll do the tire/wheel upgrade. I'm holding off on the rear M3 bushings and LSD for last since it's the most labor intensive. I was able to save money by doing the M3 control arms and coilovers myself.

Oh and I also have a 2013 DCT, with 2k miles.

[RimasRS]

Bilstein B12 Eibach pro kit which is cheap and good + M3 front wishbones, rear subframe bushings. Then save money for LSD which does not need dropping subframe like it was mentioned.

[worries]

Originally Posted by RimasRS

Bilstein B12 Eibach pro kit which is cheap and good + M3 front wishbones, rear subframe bushings. Then save money for LSD which does not need dropping subframe like it was mentioned.

Yeah I thought it did, but did some searching and you're right. One said similar parts are removed for both installs.

[josh135]

I would try out the Fortune Auto 500's or 510's coilovers out. I wish I would of went with these but they seem pretty awesome plus you can do a swift spring upgrade down the road. My suggestion is get rid of the RFT's and do the rear subfrarmes. Night and day when I did both of these things.

[miro2296]

Suspension for sure. Get the M pieces and coils.

[Stohlen]

Originally Posted by vampire81

got $2500 to spend. should i save more and get a LSD or upgrade the suspension, and what to upgrade specifically!

thanks for your help,

Answer: Buy LSD now...

http://www.1addicts.com/forums/showthread.php?t=847743

[HP Autosport]

Depends on what you will be using the car for. An LSD SIGNIFICANTLY chances the handling characteristics of your car. If I had to modify a car I would splurge on an LSD as the very first modification. With that being said, you have enough money to purchase a fairly good coilover setup so it is not an easy decision. I would buy the LSD and use the left over money to purchase the M3 front control arm kit.

-Mike

[BMW86]

I've done it all. I would go coilovers then LSD.

[int2str]

Originally Posted by vampire81

should i save more and get a LSD or upgrade the suspension, and what to upgrade specifically!

You should sell your car, add the 2500 and use it as a down payment for a lightly used F1 car. Or at least a Ferrari FXX or something. Why the hell not? Apparently nobody around here cares what problem you're actually trying to solve; not even you apparently...

When I'm thirsty, I buy a bottle of water, when I run out of disk space I buy a new hard drive. Without knowing what the problem is, recommending LSD vs. suspension is pointless.

Sounds like you haven't thought about it either. What do you want the LSD for? What problem do you thinks it solves other than "add LSD to my forum signature"? Why are you guys so bent on spending money on things without determining what they're good for?

You say you want more grip when cornering. What kind of cornering?
Grip where, front, rear?
Grip when, under braking, while turning, accelerating?
Have you considered doing an M-Performance school instead of modifying your car?
Or using the $2500 for 50 (!) autocrosses?

You mention not wanting to sacrifice ride quality. What's a sacrifice to you?
Most of the things that make a car better for the track, make it worse for the road.

Meh, your money, what the heck do I care...

It is par for the course though that nobody around here pauses with expensive LSD/coil-over suggestions and addresses the tires mentioned here first, but I gotta say though, pretty disappointed by "HP Autosport"'s reply.

I hope that's not the new name for "HP Autowerks" and is an unrelated shop. Because Harold @ HP Autowerks has always given me great advice (including installing my LSD), but Mike's comment there is less than helpful and even a bit misleading on our e-diff assisted cars.

[BMW86]

OP - I see you've got a DCT. You might want to scrap the LSD idea and focus on the coils etc. Too many $$$. Bolted ftw

[uwood]

Wow. That escalated quickly.

[ilikebmxbikes]

Originally Posted by int2str

You should sell your car, add the 2500 and use it as a down payment for a lightly used F1 car. Or at least a Ferrari FXX or something. Why the hell not? Apparently nobody around here cares what problem you're actually trying to solve; not even you apparently...

When I'm thirsty, I buy a bottle of water, when I run out of disk space I buy a new hard drive. Without knowing what the problem is, recommending LSD vs. suspension is pointless.

Sounds like you haven't thought about it either. What do you want the LSD for? What problem do you thinks it solves other than "add LSD to my forum signature"? Why are you guys so bent on spending money on things without determining what they're good for?

You say you want more grip when cornering. What kind of cornering?
Grip where, front, rear?
Grip when, under braking, while turning, accelerating?
Have you considered doing an M-Performance school instead of modifying your car?
Or using the $2500 for 50 (!) autocrosses?

You mention not wanting to sacrifice ride quality. What's a sacrifice to you?
Most of the things that make a car better for the track, make it worse for the road.

Meh, your money, what the heck do I care...

It is par for the course though that nobody around here pauses with expensive LSD/coil-over suggestions and addresses the tires mentioned here first, but I gotta say though, pretty disappointed by "HP Autosport"'s reply.

I hope that's not the new name for "HP Autowerks" and is an unrelated shop. Because Harold @ HP Autowerks has always given me great advice (including installing my LSD), but Mike's comment there is less than helpful and even a bit misleading on our e-diff assisted cars.

I agree with pretty much everything your saying but in HP Autowerks's defense I think they assumed, as I assumed, that OP had plans to do both Coilovers and LSD and was asking which first to do first.

[Stohlen]

Originally Posted by int2str

You should sell your car, add the 2500 and use it as a down payment for a lightly used F1 car. Or at least a Ferrari FXX or something. Why the hell not? Apparently nobody around here cares what problem you're actually trying to solve; not even you apparently...

When I'm thirsty, I buy a bottle of water, when I run out of disk space I buy a new hard drive. Without knowing what the problem is, recommending LSD vs. suspension is pointless.

Sounds like you haven't thought about it either. What do you want the LSD for? What problem do you thinks it solves other than "add LSD to my forum signature"? Why are you guys so bent on spending money on things without determining what they're good for?

You say you want more grip when cornering. What kind of cornering?
Grip where, front, rear?
Grip when, under braking, while turning, accelerating?
Have you considered doing an M-Performance school instead of modifying your car?
Or using the $2500 for 50 (!) autocrosses?

You mention not wanting to sacrifice ride quality. What's a sacrifice to you?
Most of the things that make a car better for the track, make it worse for the road.

Meh, your money, what the heck do I care...

It is par for the course though that nobody around here pauses with expensive LSD/coil-over suggestions and addresses the tires mentioned here first, but I gotta say though, pretty disappointed by "HP Autosport"'s reply.

I hope that's not the new name for "HP Autowerks" and is an unrelated shop. Because Harold @ HP Autowerks has always given me great advice (including installing my LSD), but Mike's comment there is less than helpful and even a bit misleading on our e-diff assisted cars.

Wow... and I thought I was a douchebag on forums... Completely unnecessary as he was asking a legit question with a legit reason. I.e. I'm gonna buy both, which will have a greater overall positive effect I can have fun with while I save for the other option?

[lastMleft]

Tough call, if you plan on doing both at some point its a toss up.

[vampire81]

hahaha
well thanks for the advices.
to clarify, the car is not going to be a track monster, and i want to benefit what i'll pay for in the "street".
the problems i'm having right now is moderate acceleration became difficult without spinning, happy tail!
second thing, car bounces in the corner and if it spins, it does violently.

the LSD will cost me $5000,, DCT here

[_Ryan_]

B14 PSS
M3 arms front and rear
Whiteline subframe inserts.

Boom, 2.5k

Then LSD.

Reason: By now, most cars are due for shocks and bushes, both of which sucked the day they left the factory. I wouldn't do the swaybar until the above is complete as you might find the balance is actually to your liking.

[John_01]

M3 rear subframe bushes, M3 front arms, M3 front sway bar.

The car desperately needs some proper dampers. The stock ones are hopeless and together with wobbly rear subframe bushes I don't think the stock suspension is worthy of either more power or an LSD. I believe the trouble you have with the car being tail happy is mostly to do with the flex in the rear subframe bushes.

[RimasRS]

Originally Posted by John_01

M3 rear subframe bushes, M3 front arms, M3 front sway bar.

The car desperately needs some proper dampers. The stock ones are hopeless and together with wobbly rear subframe bushes I don't think the stock suspension is worthy of either more power or an LSD. I believe the trouble you have with the car being tail happy is mostly to do with the flex in the rear subframe bushes.

good answer..

[HP Autosport]

Originally Posted by int2str

You should sell your car, add the 2500 and use it as a down payment for a lightly used F1 car. Or at least a Ferrari FXX or something. Why the hell not? Apparently nobody around here cares what problem you're actually trying to solve; not even you apparently...

When I'm thirsty, I buy a bottle of water, when I run out of disk space I buy a new hard drive. Without knowing what the problem is, recommending LSD vs. suspension is pointless.

Sounds like you haven't thought about it either. What do you want the LSD for? What problem do you thinks it solves other than "add LSD to my forum signature"? Why are you guys so bent on spending money on things without determining what they're good for?

You say you want more grip when cornering. What kind of cornering?
Grip where, front, rear?
Grip when, under braking, while turning, accelerating?
Have you considered doing an M-Performance school instead of modifying your car?
Or using the $2500 for 50 (!) autocrosses?

You mention not wanting to sacrifice ride quality. What's a sacrifice to you?
Most of the things that make a car better for the track, make it worse for the road.

Meh, your money, what the heck do I care...

It is par for the course though that nobody around here pauses with expensive LSD/coil-over suggestions and addresses the tires mentioned here first, but I gotta say though, pretty disappointed by "HP Autosport"'s reply.

I hope that's not the new name for "HP Autowerks" and is an unrelated shop. Because Harold @ HP Autowerks has always given me great advice (including installing my LSD), but Mike's comment there is less than helpful and even a bit misleading on our e-diff assisted cars.

How is that disappointing? Most people on this forum who have any mechanically inclined experience knows that an LSD is the single one modification that will COMPLETELY change the handling characteristics of these cars. If anyone is going to the track 2-3 times a year, LSD is the one modification that will provide the greatest improvement in lap time and behavior. Even to your point the customer is being a bit ambiguous and thus I asked what the car would be used for. I'm VERY well versed in these cars and their behavior. I'm also 'turb0mike' on the other forum and have extensive track knowledge and expertise. I don't need to give you a credential list but I assure you I know what I am talking about...

Originally Posted by ilikebmxbikes

I agree with pretty much everything your saying but in HP Autowerks's defense I think they assumed, as I assumed, that OP had plans to do both Coilovers and LSD and was asking which first to do first.

Thanks Marco... I was assuming the same thing. I'm bumbed we couldn't hang out in SF this weekend, I left SUPER early Sunday morning lol.

Originally Posted by John_01

M3 rear subframe bushes, M3 front arms, M3 front sway bar.

The car desperately needs some proper dampers. The stock ones are hopeless and together with wobbly rear subframe bushes I don't think the stock suspension is worthy of either more power or an LSD. I believe the trouble you have with the car being tail happy is mostly to do with the flex in the rear subframe bushes.

I would disagree and say subframe bushings and sway bars should be added last to a car. But once again the OP really didn't pinpoint what this car would be used for or specifically what he wants to improve, haha.

Moral of the story is when anyone puts up these sorts of questions it's hard to answer because everyone has different expectations of what a mod should do. Go ride in a car with a great suspension and then go take a ride in a car with an LSD. Should help out a little with your decision-making process.

-Mike

[HP Autosport]

Originally Posted by int2str

I hope that's not the new name for "HP Autowerks" and is an unrelated shop. Because Harold @ HP Autowerks has always given me great advice (including installing my LSD), but Mike's comment there is less than helpful and even a bit misleading on our e-diff assisted cars.

HP Autowerks is now HP Autosport, it's just a name change.

How was Mike's comment misleading? The OP asked for a recommendation and he received a good one.

Harold

[int2str]

How was Mike's comment misleading? The OP asked for a recommendation and he received a good one.

This part:

Originally Posted by HP Autosport

An LSD SIGNIFICANTLY chances the handling characteristics of your car. If I had to modify a car I would splurge on an LSD as the very first modification.

This is the disappointing advice (to me) - especially compared to all the good advice I've gotten from you (Harold) and your shop.

You're seriously suggesting that for a "canyon carver", the "very first modification" would be an LSD?!
And that such an LSD would "SIGNIFICANTLY" (your emphasis) change the handling characteristics of the car?
And this in a thread where the person that asks is still on RFT tires?

First I would contest the "SIGNIFICANTLY" part. Our cars are not simply open differentials, the adaptive braking does more than enough to keep power to the wheels. I would very, very much content that 90% of all people on this forum - including myself - could most likely not tell the difference between a 135i with and without LSD driving on a public road.

And when and how exactly does an LSD "SIGNIFICANTLY" alter handling characteristics of our cars?
A little bit under braking maybe? Mostly on acceleration out of tight corners probably. And how?

Does it get rid of under-steer produced by the awful RFTs?
Does it get rid of under-steer caused by the lack of camber?
Does it get rid of annoying the rear sub-frame flex that is easily more felt than LSD issues?
Does it make the car ride better during "normal" cornering?

How could we possibly know, based on the little feedback we have which problem the OP actually wants to solve?
Your recommendation for an LSD becomes just as good and valid then as my suggestion for an FXX.

If you take a percentage of driving where the LSD makes a difference and combine that with the fact that street driving is rarely possible/legal at the point where the LSD makes a difference, I would very much think that would be the *last* item anybody would recommend.

In fact, it was the last item you (Harold) had suggested to fix my last handling quibbles. Long after tires, camber plates, M3 bits, coil-overs, M3 bushings etc. were recommended and installed.

Again, not my money, what the heck do I care.
Just disappointing advice - coming from what is probably the best, most knowledgeable source of E82 suspension tuning on the market.

Plus I'm just generally grumpy about the rash suspension advice dished out by others on these forums these days, so that didn't help

And to get back on topic, from this follow up post by vampire:

i'm having right now is moderate acceleration became difficult without spinning, happy tail!
second thing, car bounces in the corner and if it spins, it does violently.

I don't think an LSD would significantly help with any of this.
Good summer tires (PSS, RS-3, Z1, Z2, Rivals etc.) will help SIGNIFICANTLY (lol) with the wheel spin.

Bounciness would have to be diagnosed a bit more, but my first gut instinct would say bushings, shocks & springs could probably cure that. I'd refer to the experts (like HP, TC Kline etc.) who are more experienced with this.

What do you mean by "If it spins, it spins violently"?
Was it bouncing and then snapped around?
You spun on a public road?
DSC off, I assume?