Body roll

[menelaos]

Bilsteins ROCK!

[Gkacmaz]

Originally Posted by M_Bimmer

How does the F15's active stabilizer bar (aka, roll bar) perform over the traditional F15 27mm stabilizer bar?

It looks like it would be just a swap. Am I missing something?

Its a pretty big difference. Without DHP but with Adaptive Suspension the car really feels boaty in comparison. With DHP it stays very flat in corners, the X5 drives much smaller than it actually is. İts not like a sedan but man for a big SUV to handle like that is incredible

[yupetc]

A major update for you folks

I sped things up and got the whole X5 build finished. Since the thread is about body roll and the stabilizer bar, I'll only shed light on how does Ultra Racing front and rear sway bars perform. Upon starting up the car and driving it around the neighborhood, I noticed the entire body roll disappeared. Though my X5 has been down for nearly 6 months, upon building the engine with brand new forged internals and a whole bunch of upgrades, I thought I would forget how it felt before I install these sway bars. But I gotta say: These sway bars really eliminated all, if any, body roll. Doesn't matter a speedy sharp corner or a slow progressive turn, the "sway" is gone. Upon each turn, it literally just want to slide me butt off the seat position upon those sharp maneuvers. Back 6 months ago, I remember it would tilt like a boat upon these turns around the neighborhood. But yeah, these sway bars are very stiff, and it made the car dash through the corners without any swaying.

There is a slight issue, though: I'm not sure if it's me rushing through the install of everything and possibly missed something; but I do experience a thump/clunk noise upon road bumps. Granted, this stabilizer install is only a small part of my build. I basically took the car and tear it down to the last part and build it back up with EVERY mod I ever wanted in one-go. As far as suspension is concerned, H&R lowering springs, Bilstein B6, new mounts, stabilizer links, etc. I ended up taking the wheels off and double checked my bolts. From a quick eye scan, everything appears to be nicely buttoned up, and tightly. But I'll spend the next weekend to re-do all joints and connections. Hopefully I can trace it and find where the sound's coming from.

I'm really hoping this noise isn't caused solely by the stabilizer bar, to the point where I'll have to put the stock one back on. But I'm not a person who can tolerate these noises. So let's see what can I find next week. But overall, if any of you are curious about body roll, these stabilizer bars from Ultra Racing absolutely does a swell job. And look at my previous few posts you'll find the eBay links to help you buy it. For under a thousand bucks, it's money well spent for folks with standard suspension to rid the body roll. Cheers and motor on, all.

[acmurda]

Originally Posted by yupetc

A major update for you folks

I sped things up and got the whole X5 build finished. Since the thread is about body roll and the stabilizer bar, I'll only shed light on how does Ultra Racing front and rear sway bars perform. Upon starting up the car and driving it around the neighborhood, I noticed the entire body roll disappeared. Though my X5 has been down for nearly 6 months, upon building the engine with brand new forged internals and a whole bunch of upgrades, I thought I would forget how it felt before I install these sway bars. But I gotta say: These sway bars really eliminated all, if any, body roll. Doesn't matter a speedy sharp corner or a slow progressive turn, the "sway" is gone. Upon each turn, it literally just want to slide me butt off the seat position upon those sharp maneuvers. Back 6 months ago, I remember it would tilt like a boat upon these turns around the neighborhood. But yeah, these sway bars are very stiff, and it made the car dash through the corners without any swaying.

There is a slight issue, though: I'm not sure if it's me rushing through the install of everything and possibly missed something; but I do experience a thump/clunk noise upon road bumps. Granted, this stabilizer install is only a small part of my build. I basically took the car and tear it down to the last part and build it back up with EVERY mod I ever wanted in one-go. As far as suspension is concerned, H&R lowering springs, Bilstein B6, new mounts, stabilizer links, etc. I ended up taking the wheels off and double checked my bolts. From a quick eye scan, everything appears to be nicely buttoned up, and tightly. But I'll spend the next weekend to re-do all joints and connections. Hopefully I can trace it and find where the sound's coming from.

I'm really hoping this noise isn't caused solely by the stabilizer bar, to the point where I'll have to put the stock one back on. But I'm not a person who can tolerate these noises. So let's see what can I find next week. But overall, if any of you are curious about body roll, these stabilizer bars from Ultra Racing absolutely does a swell job. And look at my previous few posts you'll find the eBay links to help you buy it. For under a thousand bucks, it's money well spent for folks with standard suspension to rid the body roll. Cheers and motor on, all.

that's good to hear but I'd think the lowering springs and bilsteins probably also contributed a lot to decrease/eliminate body roll.

[TOPEC]

endlinks should be tighten with the weight of the car on wheels, not on jack stands. try that maybe?

[yupetc]

Found the culprit of that thumping/clunking noise. It's the Wagner Intercooler. What had happened was the Wagner Tuning Intercooler doesn't really come with a factory compatible fastening local to secure onto the vehicle. In order to secure the intercooler, I'd have to remove the bottom girdle for the whole FMIC/AC-Condenser/Radiator cage and fashion up some sort of bracketry out of sheet metal or aluminum. I didn't do that as I really wanted to retain the factory pieces so instead, I had trimmed off the WT's FMIC tabs and simply "sat" it in place. I did trim the factory plastic cage trim pieces to finally fit the intercooler in place. But at this point, understand that no part of the intercooler is tied down. Only places securing the intercooler are that the intercooler rests on the bottom girdle, and its inlet and outlet connections are locked in. So when the car's in motion and going through uneven roads etc, it's basically swaying the intercooler front and backwards. The clunking comes from the intercooler banging on the AC condenser and thumping up and down the bottom girdle. It's also worth noting that this intercooler is all aluminum, and albeit, it's still very heavy and thus generates a lot of momentum when the car is in motion. In weeks to come, when I get a chance, I'll remove the front end again and customize enough tie-downs and rubber pads to secure the intercooler.

So glad that the suspension pieces are all in-tact. After all, the Ultra Racing front and rear stabilizer bars are officially proven to fit; and they have eliminated any residual body roll which aren't compensated by the other suspension components.

[yupetc]

Originally Posted by acmurda

that's good to hear but I'd think the lowering springs and bilsteins probably also contributed a lot to decrease/eliminate body roll.

I'm sure lowering springs and Bilstein B6 together does contribute to decrease body roll, but only to an extent. I'm saying that because prior to looking for these sway bars and arriving at this thread; I, too, had searched many threads about the F15 X5's body roll issue. It's my conclusion that the lowering springs and B6 does change the suspension characteristics, but these did not eliminate or adequately decrease enough body roll. Apparently, those who's done it describes it as a stiffer ride, easier to cut corners, but the roll are still there. There's even folks who the lowered setup looking for further ways to decrease body roll. Henceforth, I took the dive and looked around for these. And it just happens to fit and work nicely. We're lucky to benefit from the ability to use interchangeable parts between the E70 and the F15 platforms.

[whoismorggan]

yupetc Any videos of your car running the hybrid turbo? Who makes it? What kind of HP/TQ?

[acmurda]

Originally Posted by yupetc

I'm sure lowering springs and Bilstein B6 together does contribute to decrease body roll, but only to an extent. I'm saying that because prior to looking for these sway bars and arriving at this thread; I, too, had searched many threads about the F15 X5's body roll issue. It's my conclusion that the lowering springs and B6 does change the suspension characteristics, but these did not eliminate or adequately decrease enough body roll. Apparently, those who's done it describes it as a stiffer ride, easier to cut corners, but the roll are still there. There's even folks who the lowered setup looking for further ways to decrease body roll. Henceforth, I took the dive and looked around for these. And it just happens to fit and work nicely. We're lucky to benefit from the ability to use interchangeable parts between the E70 and the F15 platforms.

Awesome to hear. Following your lead I just ordered a Hard race rear sway bar. its 28mm so hopefully even better results than the Ultra. As for the front what do you recommend? Should I bother with upgrading the front sway bar or just add a strut tower brace? Thanks

[acmurda]

Actually ended up ordering the Ultra Racing front sway bar and Hard Race rear sway bar. Both will take several weeks to arrive across the pond. Will update once installed. My install will be just the above mentioned items on an otherwise stock adaptive suspension with rear air set up. Hope it's be enough to alleviate if not eliminate body roll.

[yupetc]

Originally Posted by acmurda

Actually ended up ordering the Ultra Racing front sway bar and Hard Race rear sway bar. Both will take several weeks to arrive across the pond. Will update once installed. My install will be just the above mentioned items on an otherwise stock adaptive suspension with rear air set up. Hope it's be enough to alleviate if not eliminate body roll.

Doesn't sound like you have the standard suspension; so I'm not sure if these bars are varied muchly from what you're swapping out from. But Looking at the chassis mounting locations, I'm suspecting it to have no fitment issues.

Once you have it all installed, I'm curious to see what it does to the body roll since you don't have lowered setup like mine. But I'm quite confident that the upgraded sway bars will play a big part in eliminating the body roll.

[yupetc]

Originally Posted by hellyesmorgan

yupetc Any videos of your car running the hybrid turbo? Who makes it? What kind of HP/TQ?

I'm a bit old schooled, so don't know how to host or upload a video up here. And I'm not wanting to upload a video on Youtube then link it in because I do not want to get that popular and having to host any content up there. At least at this point in my life, I'm staying low and privacy is maintained. For that I'm sorry.

On the Hybrid Turbo, I'm sorry if it's misleading; but upon taking the motor apart for the rebuild, I inspected the stock turbo and found a very minimal axial shaft play with the turbo's turbine. This shaft play is very minimal, less than a millimeter; and back in the old days, some newly purchased turbo's for an RB build may already have such shaft play. But today, I decided to rebuild the turbo with new internals. So I sourced all of the bearings and clips from Turbo Labs of America; they actually have a rebuild kit with an upgraded thrust bearing with better cooling channels. And I kept the exhaust propeller, but upgraded the intake compressor to a GTX9+0 Billet Compressor Wheel. It doesn't change the turbine housing requirements, but it does have a larger exducer wheel with a taller blade. Exducer wheel went from 62mm (stock) to 67mm (now). It's supposed to be lighter and spool faster and will only up the air flow by 10%. Honestly, on my butt dyno I couldn't really tell a difference since the car is currently on stock tune and it only boosts up to 8.6 psi maximum for now. Not sure what the stock boost level is supposed to be, but all I can get is 8.6 psi. So if someone can chime in on this, let me know what's the reference point. But yeah, I really don't know what turbo to call this, and since it is a hybrid of stock turbine wheel with a different compressor wheel, I'm borrowing "hybrid turbo" as the coined term here for my build.

Haven't dyno'd yet; but I'm going to keep it in this form for a few months. Once I'm comfortable with this build to be durable, I'll either drive it to Austin and have ByteTronik tune it on a dyno or I'll probably just go the MHD route and load some different maps in there and see what happens.

I also "almost" installed an M435i's oil pump into this motor. But I ended up removing it because after the installation, I couldn't zap the bolts together between the flywheel and the transmission torque converter. The reason is because the kit that I sourced comes with a manual transmission-based oil pan. And this oil pan does not have a torque converter bolt access window to tighten the bolts down. So I ended up using the original stock oil pump. But boy, that M435i oil pump really is the ideal way to go. It has two sump spouts, and it'll ensure a full supply of oil suction no matter what g-pull angle you're working the car. So yeah, I'd call my build a tad less than ideal.

[c00lbeans]

Sounds like front sway bar is a pain in the ass. Would rear swaybar only work well?

[X5Brian]

Get a tune…. I run 22 psi… my butt dyno loves it lol !
Thanks for all the hard work finding the sway bars !

[acmurda]

Also noticed that since the E70/F15 use same bars. People may want to just try an E70 Oem rear sway bar which is 24.6mm compared to the 22mm found on the f15. Thats assuming its stiffer, because diameter alone does not determine stiffness, properties and quality of material used is a big factor. The 22mm in the f15 could be just as stiff as the 24.6mm on the E70.
I'm just really hoping the almost $1000 Canadian I just spent on the aftermarket bars I mentioned above is going to be a worthwhile investment.

[yupetc]

Originally Posted by c00lbeans

Sounds like front sway bar is a pain in the ass. Would rear swaybar only work well?

I suppose rear sway bar "may" help, but I cannot see the full anti-roll being done without the front sway bar too. More and more within the week, I've tried all sorts of cornering and each time at higher speeds. I can absolutely say that the front sway bar really took the sway out, and the rear stiffness is a supplementary help. I also helped service a friend's X5, same year, but it's an s-drive. But same standard suspension. After service, I took it for a spin and boy, that front end sway is really bad. It plows in its natural sway, very evident on the front end. The rear end feels "twisty" at best. Although I'm testing the corners with quite high a speed to see this sluggish sway response. On normal driving and slow cornering, it's really no big deal. But yeah, just this weekend I am able to seek a real comparison between my setup against a stock setup. It's very drastic with both sway bars installed.

[yupetc]

Originally Posted by acmurda

Also noticed that since the E70/F15 use same bars. People may want to just try an E70 Oem rear sway bar which is 24.6mm compared to the 22mm found on the f15. Thats assuming its stiffer, because diameter alone does not determine stiffness, properties and quality of material used is a big factor. The 22mm in the f15 could be just as stiff as the 24.6mm on the E70.
I'm just really hoping the almost $1000 Canadian I just spent on the aftermarket bars I mentioned above is going to be a worthwhile investment.

I think you may be onto something great here. There are only so many materials to choose from, and from one platform to another (and E70/F15 being so close in semblance) I do not suspect BMW would prescribe a material change unless the previous material either shows signs of failure or if the new material will substantiate savings to change onto. And in this case you're proposing, BMW has no real incentives to make the change. In fact, they do get cost savings by directly coming to a smaller diameter sway bar, which is evident here. And I did drive a E70 X5 for about a year, I can safely say that the E70 body roll is much less than these F15's are.

So yeah, I think you may have found the optimal/economical rear sway bar solution to our ever-so-lacking aftermarket support on the F15's.

[yupetc]

Originally Posted by X5Brian

Get a tune…. I run 22 psi… my butt dyno loves it lol !
Thanks for all the hard work finding the sway bars !

A tune is in its due course my friend. Henceforth, the build of forged internals. However, I must stay disciplined and drive without a tune for a good half a year or so. After ensuring the build to be durable, I'll start venturing out for a tune, an X-delete, and a transmission remap. Very inspiring to hear about your 22psi butt dyno. Thanks, bro.

[M302_imola]

Originally Posted by yupetc

I'm a bit old schooled, so don't know how to host or upload a video up here. And I'm not wanting to upload a video on Youtube then link it in because I do not want to get that popular and having to host any content up there. At least at this point in my life, I'm staying low and privacy is maintained. For that I'm sorry.

On the Hybrid Turbo, I'm sorry if it's misleading; but upon taking the motor apart for the rebuild, I inspected the stock turbo and found a very minimal axial shaft play with the turbo's turbine. This shaft play is very minimal, less than a millimeter; and back in the old days, some newly purchased turbo's for an RB build may already have such shaft play. But today, I decided to rebuild the turbo with new internals. So I sourced all of the bearings and clips from Turbo Labs of America; they actually have a rebuild kit with an upgraded thrust bearing with better cooling channels. And I kept the exhaust propeller, but upgraded the intake compressor to a GTX9+0 Billet Compressor Wheel. It doesn't change the turbine housing requirements, but it does have a larger exducer wheel with a taller blade. Exducer wheel went from 62mm (stock) to 67mm (now). It's supposed to be lighter and spool faster and will only up the air flow by 10%. Honestly, on my butt dyno I couldn't really tell a difference since the car is currently on stock tune and it only boosts up to 8.6 psi maximum for now. Not sure what the stock boost level is supposed to be, but all I can get is 8.6 psi. So if someone can chime in on this, let me know what's the reference point. But yeah, I really don't know what turbo to call this, and since it is a hybrid of stock turbine wheel with a different compressor wheel, I'm borrowing "hybrid turbo" as the coined term here for my build.

Haven't dyno'd yet; but I'm going to keep it in this form for a few months. Once I'm comfortable with this build to be durable, I'll either drive it to Austin and have ByteTronik tune it on a dyno or I'll probably just go the MHD route and load some different maps in there and see what happens.

I also "almost" installed an M435i's oil pump into this motor. But I ended up removing it because after the installation, I couldn't zap the bolts together between the flywheel and the transmission torque converter. The reason is because the kit that I sourced comes with a manual transmission-based oil pan. And this oil pan does not have a torque converter bolt access window to tighten the bolts down. So I ended up using the original stock oil pump. But boy, that M435i oil pump really is the ideal way to go. It has two sump spouts, and it'll ensure a full supply of oil suction no matter what g-pull angle you're working the car. So yeah, I'd call my build a tad less than ideal.

I did some data logging with the BM3 (bootmod) app. All of the numbers below are max psi.

stock = 10
BM3 stage 1 93 octane = 18
BM3 stage 2 93 octane = 20

Originally Posted by X5Brian

Get a tune…. I run 22 psi… my butt dyno loves it lol !
Thanks for all the hard work finding the sway bars !

What tune are you running? 22 psi is impressive, but also right at the limits on this stock turbo.

[X5Brian]

MHD stage 2 plus.
It constantly hits 22-22.5 psi when I log.
I obviously don't drive it that way all the time, but it's nice to have when passing
I do change my oil every 5k now with increased pressure.
Btw sounds amazing to purge 22 psi with my blow off valve and new hood !!

[X5Brian]

So I took the X on some crazy corners with my bc kit, 16k front and 24k rear springs, 23 clicks firm. Used every ass muscle I had to hang on… but damn I want these sway bars now … every little bit helps !
Thanks again for spending my money bro! Bahahahha

[yupetc]

Apparently the Wagner Intercooler is giving me a lot of hell. For one, I couldn't install it the way they had those mounting tabs designed. It would totally eliminate the bottom plastic girdle and I refuse to do it. And the way I had it installed, it leaves the intercooler just clickity-clackity, clunking noises every time I go over bumps. I'd imagine for my case it's worse since I now have stiffer suspension setup by lowering and sway bar upgrades. I did try to use a bunch of 1-2 centimeter thick pads to cushion it in place which helps. But this morning while going to work, piping to the intercooler popped out. I'm left with a N/A car and a nice engine light on the dash. And idling has been sporadic. Forgot to bring my Carly Scanner, but I'm quite sure it's a A/F mixture error where MAF/MAP don't read what they are supposed to. If anything I'd suspect the car is running in open loop or some sort of safe mode. I hope I can make it home on a 22-mile drive this afternoon. But I'm planning to swap in the original intercooler for the time being.

By the way, thanks for confirming your boost levels. It helps me confirm many things. And after this I plan to take it to stage 2 on MHD and call it. My turbo has a different compressor wheel, I think it can boost a tad more than stock, but 22psi is plenty of ponies for me.