14 years - 1991 325ix, Stroker/5-Speed (N52 swap?)

[nando]

Yeah, i think next is recovered seats and heated elements, then she might even like it. :p

[tinkerputzer]

Hooray glad to hear! Now to get a fresh set of r888's on there :)

[DER E30]

Sweet! I love my Koni/GC :up:

[AWDBOB]

Glad you like the Konis, man!

You're definitely at the same ride height as me. I'm still wondering if I'm going to fry another set of boots if I throw my new axles on without raising my car up.

Also, hit up Axle Express in Schenectady, NY. They rebuild axles for $50/axle, boots included. They just did two sets of fronts for me.

I just got all poly bushings and a 19mm rear sway so I will let you know how the car feels after I throw that stuff on.

[nando]

Measure from the center of your wheel straight up to the fender lip/flare. then we will know. :)

I've had hit or miss luck with boots. I know a lot of them have gone bad from my exhaust. it's almost always the passenger inner boot that goes bad. this time both inners were bad and one outter, but the driver's inner had tens of thousands of miles on it, and I know for a fact the otter that went bad was from a track day I did in 2009. The hubs were crazy hot from braking, I think something like 800f (I had a pyrometer and wrote it down somewhere). melted the boot a bit but it didn't start spraying grease badly until now.

what I really want to do is make a heat shield for the passenger side, although ceramic coating on my headers helped a lot. the drivers outter is still fine and has hardly any wear, I think I did that one in 2006. oh yeah, these shafts have over 300,000 miles on them and have never been rebuilt.. still pretty tight. 80,000 miles have been lowered. :)

I'm not really sure you need the upgraded rear bar. my honest opinion is to leave it alone, or upgrade both.

I drove around for months with no front swaybar (I took it off to test fit the E46 bar, which hasn't quite worked yet). At first I couldn't really tell a difference, but then I put it back on. the response and cornering is a lot better, I'd never go to no front bar again. I feel like the larger sway bar in the rear with a stock front would have a similar effect.

With all the different setups I've had, I always felt that the balance of the stock swaybars are honestly about right. The only improvement that makes sense to me is to uprate both ends. I still want to finish that project and maybe put some kits together but that won't be until later this year.

I have a spare set of axles I want to send out, thanks for the tip. My CV grease days are over I think, lol. Funny how that changes - I used to have way more free time than I had money, and now I can buy whatever parts I want but I don't have the time to put them on my car..

[AWDBOB]

Measure from the center of your wheel straight up to the fender lip/flare. then we will know. :)

I've had hit or miss luck with boots. I know a lot of them have gone bad from my exhaust. it's almost always the passenger inner boot that goes bad. this time both inners were bad and one outter, but the driver's inner had tens of thousands of miles on it, and I know for a fact the otter that went bad was from a track day I did in 2009. The hubs were crazy hot from braking, I think something like 800f (I had a pyrometer and wrote it down somewhere). melted the boot a bit but it didn't start spraying grease badly until now.

what I really want to do is make a heat shield for the passenger side, although ceramic coating on my headers helped a lot. the drivers outter is still fine and has hardly any wear, I think I did that one in 2006. oh yeah, these shafts have over 300,000 miles on them and have never been rebuilt.. still pretty tight. 80,000 miles have been lowered. :)

I'm not really sure you need the upgraded rear bar. my honest opinion is to leave it alone, or upgrade both.

I drove around for months with no front swaybar (I took it off to test fit the E46 bar, which hasn't quite worked yet). At first I couldn't really tell a difference, but then I put it back on. the response and cornering is a lot better, I'd never go to no front bar again. I feel like the larger sway bar in the rear with a stock front would have a similar effect.

With all the different setups I've had, I always felt that the balance of the stock swaybars are honestly about right. The only improvement that makes sense to me is to uprate both ends. I still want to finish that project and maybe put some kits together but that won't be until later this year.

I have a spare set of axles I want to send out, thanks for the tip. My CV grease days are over I think, lol. Funny how that changes - I used to have way more free time than I had money, and now I can buy whatever parts I want but I don't have the time to put them on my car..

I shall do just that (measure) later on today! And it really is hard to tell with these damn boots. When you install them do you leave a little extra slack for the added angle they're at from being lowered? The ones on the axles I just put on were pretty tight without much give, and I'm thinking that's what may have caused it.

I've always found that cars come with a touch of understeer from the factory, and I've felt that specifically with the iX since I've had my suspension on. I'm thinking that the bigger rear sway will help tighten up the back end and correct the understeer. I also did a solid diff bushing and poly trailing arm bushings to combat the same issue, so we shall see how it works out.

That is funny. It seems that in the stage I'm in I don't have the time or money

Edit: In the picture on the previous page, are you on 225/50 R888s?

[nando]

there will always be a touch of understeer on an ix - I've gone down that road too, and you don't want to eliminate all of it. do you already have camber plates? the biggest issue is overheating the outsides of the front tires (due to lack of camber). otherwise, if you eliminate all of the natural understeer the car will be very twitchy at the limit and prone to snap oversteer.

Other than maxing out front camber the solution is to adjust your driving line and just accept that you will have a little understeer - the trade off is you can be back on power much sooner and get away with a lot of stuff the RWD cars can't.

yeah, they're 225/50 R888s. I got this set in 2012, from 2009-2011 I ran 235/50 R888s. I like the 225s better.

[AWDBOB]

there will always be a touch of understeer on an ix - I've gone down that road too, and you don't want to eliminate all of it. do you already have camber plates? the biggest issue is overheating the outsides of the front tires (due to lack of camber). otherwise, if you eliminate all of the natural understeer the car will be very twitchy at the limit and prone to snap oversteer.

Other than maxing out front camber the solution is to adjust your driving line and just accept that you will have a little understeer - the trade off is you can be back on power much sooner and get away with a lot of stuff the RWD cars can't.

yeah, they're 225/50 R888s. I got this set in 2012, from 2009-2011 I ran 235/50 R888s. I like the 225s better.

Gotchya, duly noted. I already have the rear sway so I'm going to run it and see how it feels.

And nope, haven't picked up the camber plates. They're like 3x more than I could ever see myself paying for camber plates. My Ohlins plates for the Evo ($4500 coilovers) were only $130ea, so I find it kind of ridiculous that GC wants $400 for them.

And sweet. I think I'm going to stuff a 225/50 r888 on my weaves this time around and see how they work out!

[nando]

the quality is fantastic though - and also the only game in town for the ix, unless you want to lose a couple inches of travel.

the bearings for the springs are these crazy German made UHMW Polyethene doughnut shaped things that don't actually have moving parts (no rollers, balls, needles, etc). UHMW is a super tough material and it's almost as slippery as Teflon - we use it in industry all the time for things that last 50+ years out in the elements.

[AWDBOB]

the quality is fantastic though - and also the only game in town for the ix, unless you want to lose a couple inches of travel.

the bearings for the springs are these crazy German made UHMW Polyethene doughnut shaped things that don't actually have moving parts (no rollers, balls, needles, etc). UHMW is a super tough material and it's almost as slippery as Teflon - we use it in industry all the time for things that last 50+ years out in the elements.

I guess that's cool and all ;) At least you're getting a good product for your money.

They will definitely happen before tires and final alignment.

[The Dark Side of Will]

I've always found that cars come with a touch of understeer from the factory, and I've felt that specifically with the iX since I've had my suspension on. I'm thinking that the bigger rear sway will help tighten up the back end and correct the understeer. I also did a solid diff bushing and poly trailing arm bushings to combat the same issue, so we shall see how it works out.

You can't fight physics. The physics is that the front end is heavier, the front contact pressure is higher than the rear and the front tires will slide first.

The iX is more front heavy than other E30's AND loads the front tires with drive torque. The only way to eliminate understeer is to give it a bulldog stance with significantly wider front tires than rears... and then you're still at the mercy of the camber challenged front suspension.

Fieros are similar, but the other direction... 45/55 weight distribution with square tire fitment from the factory. It tended to oversteer, so GM used a big front bar to try to make it "safe" with understeer. They just succeeded in making it snap oversteer. It is possible to upgrade a Fiero with a square tire fitment and have it handle ok up to the limit, but once it starts to slide, it's back to physics and oversteer... which means that it's basically unrecoverable once you push just a smidge too hard.

The only way to get it right is to dramatically widen the rear tires and stiffen the rear suspension. I'm running 205's with stock springs, softer than stock bar and Konis front, but I have 245's with 325# springs and Konis rear. The stock rear spring rate is ~190. It's pretty darn neutral and easy to recover from a slide. A rear bar actually makes it harder to drive.

I also did a mild job on my Pontiac 6000 AWD. With Koni struts, minivan springs, 16x8 wheels and 245/50's on the front and 16x7 wheels with 205/60's on the rear, it was close to neutral, yet had 60/40 weight distribution. It had an open (but lockable) center diff, so minute variations in tire size didn't bother it.

Not sure if we can get close enough to the same diameter front/rear to have a differential fitment not hurt the VC in an iX.

Edit: 225/50's and 205/55's should be close enough to the same diameter to work.

[nando]

there's no reason to run different front and rear tires. the amount of understeer left in a well setup ix isn't enough to cause any issues. it's not a fiero. :p

whatever minimal amount I couldn't dial out with suspension I could alter with tire pressures. camber and roll stiffness are going to help the most. as far as front heaviness, it's not really that front heavy - it's still really close to 50/50 (52/48 or something like that). it's not an audi either.

I kept a log of my tire temps that I took with a pyrometer. if you are overheating the outside edges of your front tires then the car will understeer. the most obvious way to fix that is more camber, caster, and more roll stiffness. more tire pressure up front helps too, I typically ran 50/30 psi with the hoosier A6s. on regular tires the delta is smaller but I still typically ran more up front than in the rear. but if you can get the front tires to heat evenly there's really no issue. with a bit more power the car will throttle steer too.

to be honest all you're going to do is reduce the car's overall grip and make snap oversteer more likely. I still got heat into the rear tires it just took longer to happen.

[The Dark Side of Will]

as far as front heaviness, it's not really that front heavy - it's still really close to 50/50 (52/48 or something like that). it's not an audi either.

Lol, funny you mention that... My girlfriend's '02 A6 is 60/40, as was my Pontiac 6000 AWD. The Audi never lets you forget it, either.

I thought the iX would be worse than that... I thought a regular RWD E30 had worse weight dist than that, for that matter...

I kept a log of my tire temps that I took with a pyrometer. if you are overheating the outside edges of your front tires then the car will understeer. the most obvious way to fix that is more camber, caster, and more roll stiffness.

Lol, only one of the three is available in an iX! ;)
I used to think that Adem Ergen's AWD M3 build was barking up the wrong tree by keeping the M3 strut towers and caster, but now I'm thinking he may have arrived at a good answer for the wrong reasons.

with a bit more power the car will throttle steer too.

Interesting...
The aforementioned A6 theoretically has a 40/60 power split, but only understeers when I apply power in a corner.

to be honest all you're going to do is reduce the car's overall grip and make snap oversteer more likely.

My experience with the Fiero is the opposite... you're more likely to end up with a car that's hard to handle and has snap oversteer if you're fighting the tires and weight dist than if you're working with them.

I'll give the 225/50 & 205/55 combo a go if I can find an economical wheel swap to put 8's on the front and keep 7's on the back.

Don't forget that stiff bars on both ends ALSO reduces overall grip.

[nando]

what do you mean? you can add plenty of camber with camber plates (more than -3 degrees) and enough caster with the plates and offset bushings. I don't think you'd want the strut towers totally upright, there's got to be a reason the ix only comes with 1* of caster stock.

I really don't think there's a point to different tires. seriously - I went through a lot of A6's in my day. All it will mean is you can't rotate them so they will wear out faster.

[The Dark Side of Will]

Cool. I didn't realize there was that much static camber available. Obviously with 2.5" ID springs, there's a lot more room to move the strut around inside the strut tower.

Stiff bars increase weight transfer. They're used to make the end with lower contact pressure have less grip to match the end with higher contact pressure.

BMW has to put their steering racks under their engines.
The inner ball joints have to be located close to the inner tie rod ends to minimize bump steer.
The knuckles have to fit inside wheels of a certain size.

These packaging requirements mean that BMW strut front suspensions end up with low roll centers.
This means that they don't get camber gain from the roll center and instead need to use a lot of kingpin inclination to get camber gain. The E46's have something like 17 degrees of steering axis inclination (SAI)
Using a lot of kingpin angle means that there's no caster-induced camber gain available, and the tire actually loses camber at higher steering angles. In order to have caster induced camber gain, caster angle has to be greater than SAI.

All of this means that BMW strut front ends do a horrible job at maintaining camber and making good use of tires.
That means that BMW strut front ends need to be very very stiff in order to minimize body roll... which is why really stiff bars help almost no matter what.

E46 Xi's end up with 5-6 degrees of caster stock, so I guess BMW rethought their understanding of how caster and AWD interact... Or maybe they just didn't want to build an AWD-specific body anymore.