Subframe Reinforcement Pt 2 Solid Subframe Bushings | E46 M3

In this video I clean up the underside of the car and install the Turner Motorsport aluminum subframe bushings as well as the Powerflex differential bushings.
Instagram: / kyle.reese6511
Sponsored by Turner Motorsport: goo.gl/NuCI2B
-------- Camera and Gear I'm using --------
Camera - Canon 70D: amzn.to/2yNtXua
Lens - EFS 24mm f2.8 STM: amzn.to/2xnwVUI
Mic: amzn.to/2zCUERA
Bendy Tripod: amzn.to/2liijoe
Big Tripod: amzn.to/2lgozfT
-------- Music --------
Explorers - Hinkik
Joakim Karud / joakimkarud

[@CarsOverdose]

You're doing something no-one on KZbin decided to do. Props for that.

[@CarsOverdose]

Exactly.

[@WarriorsPhoto]

You're making this process look simple. I'm excited to see your thoughts afterwards. I bet it drove way better? 😮😊🎉

[@ericswanson5241]

I don't know how crazy you want to get with the repair but you might want to look at getting some Wurth Stone Guard undercoating. They have a grey color that is supposed to match the factory BMW stuff pretty well. It would be really interesting to see you put that stuff on your car to make it look "factory" when your done with the subframe repair. I think this is the same stuff that Reddish Motorsport uses. Their repairs really look sharp. Thanks again for the very informative videos.

[@Tito_chevere]

I have the same problem. I change the bushing from power flex black edition because I go to track day every 3 weeks. The video is very good. I like you work. Thx bro for the video

[@MEMcAndrews]

Your logic around solid subframe mounts is reasonable at it relates to the mounting point cracks. The bigger concern, though, is that solid mounts will likely increase stresses on the RACP. Which is a huge issue already. If you’re doing topside reinforcement and/or structural foam, this might alleviate the problem. If you are ONLY addressing mount point stresses, you’re in for some troubles ahead.

[@GrindHardPlumbingCo]

Killer videos man! Do you have links to the bushings too?

[@danielpyziak6537]

I think your logic is correct. Solid mount the subframe to the rest of the car to make it as rigid as possible as one unit and reduce deflection and resulting fatigue. The poly in the diff slightly dampens driveline vibration and driveline forces. In addition AKG makes some solid aluminum subframe bushing with more surface area. This surface area clamps the sheetmetal of the car between the bushing and a plate inside the car with a threaded receiver.

[@SuperSport01]

Daniel you understand and you are correct.

[@АлександрКаширин-н3ю]

Здравствуй дорогой Друг!Столько лубви и заботы к машине не каждый раз увидеть, ты большой молодец,так держать!!!!

[@bsouza1675]

A solid mount will concentrate the load. This will produce a more harsh ride. If a rubber mount is working properly (is not old and is functioning) the rubber dampens the force similar to a shock absorber. Some of the torsional energy is dissipated by the rubber deflecting. This is probably why Bmw engineers designed the suspension with rubber bushings. Granted they blew it! 😡 (I own a 2006 E46 M3) with under designing sheet metal thickness around areas with torsional loading causing shear failure. However, Bmw engineers knew this because the E36 M3 has similar problems. I would suggest possibly checking on the E46 M3 forum to determine any issues with the solid bushings. Maybe a polyurethane bushing formulated with some flex would give you what you want without the harshness of the solid bushing. I really appreciate the hard work and effort you’ve put into this huge upgrade/maintenance. Good VID! 👍

[@KyleReese6511]

Thanks for your comment! So I understand that the solid bushings will create a harsher ride, I've accepted that. I think the reason I'm staying away from the rubber bushings is because, to me at least, it seems that they would allow the mounting points to twist. I'm not sure how else to describe it but here goes: Because the rubber bushings should be able to flex in any direction (up, down, and side to side) in order to absorb the force, it seems that the bushing, at certain points of flex, would be able to apply leverage to the mounting points which would tear the metal. If this doesn't make sense, then I'm sorry for the long read haha But I really appreciate your comment and investment in the process. I find all of this fascinating and Im really enjoying discussing it.

[@SuperSport01]

B Souza the real reason for rubber rear subframe bushings is to make the car extra quiet and cushioned when new to help sell cars. The only downside to solid rear subframe bushings is more road noise being transfered into the cars interior. As long as the rest of the rear suspension components that come into contact with the rear subframe have rubber or poly bushings the noise increase will be minimal with solid bushings. The front subframe/engine cradle is mounted solidly to the car from the factory so, in my opinion, the rear subframe should be as well.

[@DaveMsport]

All new M cars have solid subframe bushes since the E92 M3 GTS. Only solid diff bushes really create bad NVH so oem bushes are best for that.

[@davidd4677]

Awesome job handling all of this build on your own! Quick edit: How long did that part of the subframe project take, ie; removal, cleaning, and bushing install? Kudos to, what appeared to be, your dad for lending you a hand on your car as well. It's always cool to see a father/son tackling an automobile project. If said hand lender was not your dad, then pass the kudos on to the appropriate recipient 😁

[@KyleReese6511]

Thank you very much! In the end, probably only a few hours. The hardest part would removing the fuel lines to the tank, super annoying! That was, in fact, my father helping me at one point. I've grown up learning a ton on various projects I've helped him with. It's really awesome to be able to transition to him being the one helping me on mine. I will pass along the kudos to him!

[@davidd4677]

@@KyleReese6511 Awesome, thank you!!

[@ShadowSlayer140]

I could be wrong but I thought the whole idea of rubber bushings were to absorb flex and forces which travel in to the subframe. As the car is put under stress such as tight turns, and sudden changes in lateral and radial forces, a harder material being used to replace the rubber bushings will have less flex, decrease the amount of time that point where the bushing of the car absorbs the impact and thus increase the overall force and strain. Kind of like how an airbag works. The airbag explodes and increases the time in which your head absorbs the sudden deceleration of a car during a crash, significantly decreasing blunt force to the head vs. having no airbag. Rubber does the same thing, flex and absorbs vibrations and force for a longer period than a hard piece of metal. Just my thought as a second year engineering student...

[@SuperSport01]

You're not wrong but the problem is the rubber bushings allow the subframe to flex on its mounting points that connect it to the floor of the body. This applies different loads to the different mounting points. Which causes the subframe mounting points in the floor to flex and crack. Solid subframe mount bushings apply loads more evenly and reduce flex which makes cracks in the floor much less likely to occur.

[@CameronHall-wq9tk]

Love the Easter eggs in the background of this vid...;)

[@agustinaguero3601]

?

[@Ismailabousaad]

proper tools for the proper job

[@leedavies9309]

keep up the good work looks great

[@BrokenBMW]

Love your videos! E46 M3 is my dream BMW, I just wish it didnt cost 40-50K USD here gaaaah

[@stefancarle906]

I strongly advise you again to check redish motorsport's videos while you've got the frame out there are a lot of other areas you should be checking.

[@KyleReese6511]

Being looking at Redish for the last few hours now, thank you for pointing them out! It will definitely affect how I tackle the welding and reinforcement.

[@stefancarle906]

@@KyleReese6511 there's a good few areas where spot welds can flex and move slightly, you can't see the full picture without taking sealer off and also the top of the subframe mounts usually crack also which are only accessible by going in through the inside. While you've gone to this effort you'd be as well to cover all bases.

[@KyleReese6511]

Stefan Carle yep, I agree. I might as well go all the way. For what it’s worth, I haven’t removed the undercoating yet because I wasn’t prepared to weld. Once I’m ready to and confident with my welding, I’ll remove the undercoating and do more inspecting. I’ll be going in through the trunk as well.

[@DaveMsport]

Should really add a brace to the top side of the racp under the top boot floor skin that will connect the subframe mounts to the chassis rails directly. Any other repair such as plates glued or welded on underneath is just a localised solution and not addressing the reason the panel fails in the first place. Nice work all the same however :) Google E46 Vince brace and you'll see exactly what I mean.

[@TheBlackdragon936]

Dave That’s not guaranteed to work either. Just a part that was created in theory.

[@derickslatford5449]

Hi Kyle I was watching a you tube vid on how to make your own poly bushes, I'm going to do my own I have a c class 1999 2ltr pet I was thinking of going down to a brakers yard and taking off all the old ones and doing those that way I can still use my car.

[@Poochie1986]

Motivating

[@m3g670]

nice work man, just abouth to do the same stuff on my e46 m3 03 convertable but i got crazy reading posts for these bushings, so any advise what shoul i do what subframe,what diff bushings by the way how do you like ur setap after some time? im not looking for track use

[@nitsuga262]

No entiendo casi nada de inglés pero me encantan tus vídeos

[@thomasarussellsr]

Looks like you're doing a great job. See you in the next video, but you won't see me, because this video/KZbin thing is not bi-directional. LOL

[@emptyS14]

What bushing removal/install tool kit did you use? Thx

[@jesusdelosrios3892]

What wheels are those?

[@flydog431]

What tool did you use to install the subframe bushings?

[@abdurrehmansawlayh1792]

ANY FIRST TO EVERY THINGS!

[@zerotohero7449]

Did you find you had to add a big washer to the front diff mount bush? I have the same powerflex bushes on my e46 m3 diff and it just didnt look strong enough without adding a big washer to the front mount.

[@KyleReese6511]

Zero to hero I didn’t add any washers to the diff bushings at all. Everything seemed solid. I don’t see there being an issue.

[@DanielRodriguez-jb9bq]

@ 7:25 ... special tool? What’s the part #?

[@THECAPTAIN-ev7bj]

👍👍👍👍🔥✌️

[@Mini360]

Your logic on the solid bushings is flawed. The force from the drivetrain will project directly into the floor. With the rubber or polyurethane bushes this force will be absorbed by the bush rather than going straight into your freshly reinforced floor.

[@KyleReese6511]

Thank you for your input! That makes a lot of sense.

[@SuperSport01]

No Mini360 his logic is correct. Solid bushings will reduce the chance of high loads be applied to an individual mounting point by evenly distributing high loads across all mounting points. Thus reducing the chances of the cracks reoccurring. The only downside is more noise will the transferred into the interior.

[@icebox829]

but wouldn't the polyurethane bushings be plenty stiff to prevent too much force on one particular mounting point? why would you need to go directly to the aluminum bushings?

[@DaveMsport]

New F8x M3 and M4 have solid alloy bushes anyway and it was first introduced on the E92 M3 gts and worked well so bmw rolled it out on all M cars. E46s need alot more than just plates welded onto the underside to properly address the issue but solid bushes are no harm at all. Oem differential bushes are worthwhile though

[@MrAgustincuenca]

indeed you are correct. The rubber or soft bushings are in fact dampers of the vibrations rather than stress transferring points. The stiffer/harder you go the more the chassis will have to absorb hence crack if not reinforced.

[@dongkyukim3580]

how many miles does your car have?

[@cunrah]

Great job! What milage is your car on?

[@KyleReese6511]

138k?

[@Steve-bh3zg]

Pt 1 ???

[@ericksaenz4905]

Me gustaba mas la otra cancion del intro. Pero excelente tu equipamiento de tu garage

[@DemizeJr1]

Why can't someone do the epoxy method after the points have been welded??

[@stefancarle906]

Also if you put the bushes in the freezer for a while before fitting them it would have took less effort

[@KyleReese6511]

I've never heard of that before, that's interesting.

[@chris-oy9jn]

You might aswell change the clutch while your at it

[@darinworthington]

You are going to get a lot of road noise from those solid bushing, also the rubber/polyurethane will absorb some of the twisting force.

[@gotany1]

You could have given your buddy a fuss when putting jet wash togeather.

[@miccho159]

1

[@ericswanson5241]

Good job on tackling this job yourself. Maybe I missed something, or there's a part 3, but how did you put the reinforcement plates in the car? Epoxy or weld? Also I think your going to have issues with the new bushings as they are too rigid and will transfer too much driveline shock back into the known weak area on this chassis. Bushing are used to allow some sort of shock dampening and movement so forces aren't directed back to the chassis. I guess the reason you used them was to not allow for flex or movement of the driveline energy so that all the energy goes to forward momentum and not driveline flex. Used frequently in race cars but I doubt you will ever notice the difference plus ride quality should be abysmal. Just my humble opinion.

[@KyleReese6511]

Yep, I'm working on part 3 right now! I'll be welding my plates on. I appreciate your opinion! I can't speak from experience yet, but I don't mind a stiff car. It's my taste. To some I'm sure the ride quality will be greatly diminished but I'm interested to see how it compares. Either way, I think I'll personally be happy with it.

[@vincentrdelinares6732]

E46 rear chassis is a chips.... deformation of rubber absorbe à lot of stress. Aluminium just transfer the stress on the châssis

[@dsbdrifter]

Just a little extra info on what you are doing in regards to the reinforcement plates once you have repaired the cracks and wielded in the plates you will need to cut holes in the boot well above where the subframe sits to check for internal cracks as there are multi layers that are not visible which may have cracks as well. In which if not repaired everything your doing will be in vain and the rear floor will de-seam itself and the rear will drop on the left side due the offset diff also the top plate between the wheel wells will crack inwards as this is a mistake alot make when doing this repair . I have a video of the results of what will happen if this is not done well doing the repair as the car in the video had the plates added and has cracks, and floor has de-seamed itself also tears big enough for me to put four fingers inside. I've repaired enough of them to know what will happen if not done correctly and thumbs up for the powerflex and aluminum subframe bushing as that is what we use on our race car builds. If you can though kinda expensive change your trailing arm bushes to the solid bearing type which takes the load better and helps with force loading on other components.