M20B29 w/ Triple Webers into my '71 2002

[SkiFree]

BMW 2002 Front Subframe installation.

Going to breeze over this a bit.

To drop the front subframe I unattached the steering colum from the box (unbolted the four bolts inside the cabin where the steering column attaches to the fire wall and the steering coupler in the engine bay, couple good yanks on the steering wheel and it's separated.), unbolted the engine mounts, the strut mount hats, ground wire, and some other bits.



With the car off the ground we wheeled in the cherry picker to hold the engine in place. We unbolted the 6 bolts which attach the subframe to the frame rails and out cam the old subframe, complete with strut assemblies.









Slid in the new subframe assembly and started to raise it up on a jack. The billet pieces used for the IE sway bar utilize the forward two subframe-to-framerail holes, so they are held on pretty tight. It was tricky to line up the subframe holes (and the motor mounts) but it worked after some grunting and repositioning of the jack.





We were reusing the upper spring perches (making sure they weren't mushroomed) so the upper assembly had to come apart. Most common reason people will get ticking in the corners or going over bumps with their newly refurbished suspension is because they do NOT leave enough space between the upper spring perch and the strut bearing, These need to be completely isolated from each other because as the strut bearing is bolted to the body shell and remains stationary, the upper spring perch twists as you twist the steering wheel. If you do not have enough spacing between two plates (washers) then they will bind with eachother resulting in the clunking/banging. This also holds true for adjustable camber plates.





The fixed camber plates go between the strut bearing and the body shell, it relocated the upper spring perch in-board. The plate and perch didn't want to cooperate very well and so a bench vice was needed to press them together.

With the subframe in and the struts now ready we slid in the strut assemblies and bolted the tops to the body and the bottom to the control arm.

The sway bar end links were next. To properly set the end links while the car is up it's best to disconnect the heim-joint from the rest of the link (snug the link down on the control arm) and jack up the the drooping control arm up simulating the arms position while on the ground (this way the bar will have NO pre-loaded stress when driving). The heim-joint and link will line up, simply attach and tighten down.







Brake setup.
The hardlines on the strut were stripped before we touched them, so we had to bend up some new ones. Didn't have much time to spend making them look pretty, but they work. The inner hardlines were luckily not stripped, used the IE stainless flex lines to finish the connections.



Caliper and rotor in place. Make sure the caliper is centered over the rotor, I have had to use different size shims along the caliper bolt (tolerances were not always consistent with the Volvo calipers).



Reattached the steering column (couple of good shoves from inside the car) after swapping over the grounding wire on the steering coupler setup.

After attaching the tie rods to the steering arms and remounting the wheels, we did a manual alignment (old fashioned tape measure and string) and I headed on home with a much nicer behaving suspension.

[SkiFree]

Thanks Igor and Jeremy, as always it's nice to watch both of your projects.

Jeremy, you should see the AFPR tomorrow.


Just made the hard decision to NOT go stroker, the costs would be similar but my goal is to have this engine last long term (and possibly be a daily driver for a bit), the finicky nature of a high-strung engine is not what I'm looking for. Will see how much power is available from a well-buttoned everything-new engine.

[catuned]

Look at you! Your a bad ass! Love this thread! Just found it.. I'll keep watching.

[deutschman]

Nice job on the front subframe write up! I'm going to have to go over mine again when I go coil over late this summer. Just ordered a fuel regulator for my m20 from you guys. Can't wait till it shows up. I still want a thicker spark plug set from you guys.

[SkiFree]

Thanks guys...... Next up is the front assembly. I apologize if some of this seems basic or redundant, just wasn't to make sure I address often asked questions. If there is something I miss please let me know.



1. BMW 2002 Front Subframe reassembly (Street Performance oriented)

Written by myself, Andrew Adams, with much help and teaching from Jeremy. This is intended to go up on our expanding Ireland Engineering Tech Section to help answer some of the questions we get asked regularly.

BIG DISCLAIMER: I am not responsible for your screw-ups.

GENERAL TIP:**Never fully torque down a bolt intended to hold a pivoting bushing into place until after the full weight of the car is applied.**(This is generally why you’ll see someone stress out and say their car is sitting like a 4x4 after going through their suspension)

__________________________________________________ ______



Starting with a blank powdercoated front subframe makes things nice.**The first thing I did was press in the Idler Arm Bushings (this would be a pain to do later on), the powder-coater was kind enough to mask off the holes so the new bushings were pressed in with relative ease. With the bushings in I slid the idler arm through and reused the cap washer/ castle-nut.





From there I went straight for the radius rods. I used the IE urethane front bushing kit which included the radius rod bushings as well as the inner and outer control arm bushings. Grease-up the backside half of the bushing put the zinc coated concave washer in place along with the radius rod end and push into place ( if you leave the rod out, it won't fit later). Pushed in the front portion w/washer.



**Note, the earlier cars used drilled arms, castelated nuts, and cotter pins to keep everything in place. Later cars simply used lock nuts ( radius rod nuts are 14mmx1.5mm). I used locknuts where-ever possible since there a lot easier to deal with.





The seam welded and powdercoated control arms were the next to have their bushings put in. The thinner-ended bushings went on the outside hole and the thicker were pressed into the inside .



Earlier control arms did not have the bent “I” forming edges and are obviously not as strong.



The sway bar end links were put on next. Used the jam nut to tighten the bushing but made sure to leave the heim-joint loose (for easier instal later).



Next I pushed the large bolt through the subframe and the bolt sleeve, out the other side the 'shorty' bolt sleeve was slide on along with one of the bushing washers. With another concave washer slide on the back if the radius rod, it was time to slide the control arm on. With the other side washers in place I cinched on the 2 lock nuts. (don't mind the sway bar, got a little ahead of myself.)



Sway bar
The bmw 2002 Ireland Engineering 22mm front sway bar (full name, to help google searchers) routes underneath the subframe rather than the stock (and other aftermarket bars) which route up and over the subframe tips. The maths show that it acts as strong as if it were a 25mm bar routed through the stock location. The billet mounts for the pivot bushing utilize 2 of the 3 holes which attach the subframe to the chassis frame rail. I've chosen the 'drop-center' bar which will clear the oil pan for this M20 swap. The important part of the installation will be when I attach the end links to the bar (next write up). See above picture

steering box
After loosely attaching the passenger side motor mount and keeper (NOTE that I've done this wrong, whenever possible put the bolt facing downward and the nut on bottom, so just in case the bottom backs out you'll still have the bolt in place)



it was time to attach the steering box. The steering arm bolts got a little bit of red lock tight and were completely torqued down.



The center track rod was then put in place (made sure to soak the rubber bushings in oil, as per the factory manual) and the ends bolted on loosely.




All done for now! Next up is the actual installation!

[Kershaw]

really nice job man.

$$$$$

[evanc]

Thanks for the detailed documentation. I'll be referencing your thread this summer when I'm home putting my '02 back together. Although, it'll just be the mechanical and interior that need to be put back together. Lookin real good. Keep up the good work.

[SkiFree]

I don't think I'll need to run adjustable camber/toe with stage 1's and HD's, but I guess we'll see after we do an alignment.

Simon S - Thanks, I've taken inspiration from your 'Zen' walk through's. Next up will be the front subframe.

[Simon S]

Sweet Jesus !!

Talk about building a roller skate..

[CHIF8008]

no camber/ toe adjustment kit on the rear subframe?

this is so beautiful, i wish i had the money to do this to any of my cars

[Myster-E]

Nice work! Can't wait to see the car running.

[SkiFree]

No problem J, though I'm certainly just passing along the knowledge on that one.

And now the rear suspension ....


1. BMW 2002 Rear Subframe reassembly (Street Performance oriented)

Written by myself, Andrew Adams, with much help and teaching from Jeremy. This is intended to go up on our expanding Ireland Engineering Tech Section to help answer some of the questions we get asked regularly.

BIG DISCLAIMER: I am not responsible for your screw-ups.

GENERAL TIP:**Never fully torque down a bolt intended to hold a pivoting bushing into place until after the full weight of the car is applied.**(This is generally why you’ll see someone stress out and say their car is sitting like a 4x4 after going through their suspension)
-----------------------------------------------------------------------
After getting everything back from powdercoating I started piecing together the rear subframe.

First up were the new OEM rear subframe mounts w/ Ireland Engineering urethane inserts.**The inserts go in through the top (you’ll need an exacto knife to cut through the thin rubber webbing inside the mount.**Curiously I bought the bolts from BMW, and they came stamped 9.8 (seen 8.8 and 10.9, but never a 9.8).**Bolted the mounts to the frame.*



I started with the rear wheel bearings (they are not as weird as the E30 rears).*



Upon removal of the old bearings you’ll find a shim and sleeve, keep those bagged appropriately.**The shims are specific to the trailing arm, and if you lose them it’s a PITA to calculate the correct size replacement needed (BMW had a number of thicknesses used.)



For reassembly I started with the inner bearing, (press was oh-so-nice).**Packed the bearing with grease. When pressing in the new bearings I made sure to use an appropriately sized hollow tube (you want the pressure applied on the outside ring of the bearing, pressure applied to the center sleeve will destroy the bearing (or hasten it’s demise).





For the outside I put in the sleeve and placed the shim on the inside shoulder then pressed in the greased bearing.**With the bearings in, I layered some grease up to act as the grease reservoir before tapping in the seals (don’t want to tap the seals down much past the lip as it encroaches on the grease reservoir).





Next are the stub axels.**Often upon removal the threads can get bunged up when someone mistakenly hammers them head on. Sometimes (but certainly not always if its too bad) this can be righted by filing the threads or chasing them with a thread chaser.**Try and get these as clean as possible before pressing back in (I used scotch bright).**Simply press these back in (there will be two major points of tension as it’s pressed in).





After the stub axle went on, I pressed in the shock absorber stud back into its knurled hole on the trialing arm and bolted on the brake drum backing plate (in the case, one of the 250mm sized units).**I made sure to situate the plates so that the small hole meant for the E-brake cable is on the forward side in relation to the trailing arms. The forward brake shoe retaining pin needs to be put through it’s hole at this point as well (there is not enough clearance to the trailing arm after the backing plate is bolted down.**Bolts were 8x25 with a lock washer**



Next on were the wheel hubs (also zinc plated), I tapped these on with a rubber mallet.**The infamous axle stud was then hand tightened down (the final torquing won’t be done until the car is on the ground.)



The last part of the trailing arms (before attaching the arm to the subframe) is to press in the Ireland Engineering urethane trailing bushings (part of the rear bushing kit). When looking at a single trailing arm, the thicker end bushing needs to be on the outside.**I liberally lubed up the bushings with the supplied grease (super sticky) prior to squeezing them in (a C-clamp worked nicely).



Finally attached the trailing arms to the subframe.*BigNote:**I’ve seen this covered before, but if you’re having your standard 2002 trailing arms boxed in, then you need to make sure who-ever is doing the welding is doing so on either a jig or an actual subframe.**If not, you’ll have some arms that are pinched and askew.**Depending on your trailing arms, it might be nice to have a friend around for extra muscle.**The trailing arm bolts are 12x1.5x90mm.



Next up was the brake hard line. Started with a 20” line of bubble-flared brake line. 1st bend w/ downward angle, then another bend to run the brake line along the inner arm before ending with another bend approximately where the stock line would be. Used a bit of split rubber tubing to wrap around the hardline where it goes into the retaining hook and pinch it closed. Bubble flared fittings do NOT need teflon tape since the flare acts as the seal, however Pipethread brakeline ends DO need teflon tape.



The last bit for the rear subframe is the Ireland Eng. 22mm sway bar. The endlinks are pretty straightforward, though it's worth noting that they are fully adjustable (using sliders), the more you choke up, the stiffer it acts.



The pivot bushings are a royal PITA, but with a little time and patience, they should be conquerable. The first thing is to make sure the U bracket retainer on the subframe is perfectly parallel (if not, squish it between to solid objects [like aluminum blocks] and use a hammer to straighten). Slipped the urethane bushing (w/ liberal amounts of grease) and fit the U-clamp in the bottom over the sway bar Next I started with a long-ish 8mm bolt and started cinching down enough to start a shorter bolt in the adjacent hole, repeated with ever smaller 8mm bolts. With the help of a clamp and muscle, the bracket was cinched to a snug fit.







And after that the subframe is ready to go up in the car!

[JGood]

^Holy crap!

Would have never thought to use grease somewhere like that to prevent rust. Thanks for the tip :)

[SkiFree]

Dumb question - why does this area get greased? I did mine recently and didn't see any reason to do it...

It's not strictly necessary for those of us in sunnier places. The grease is to keep moisture from sitting in there and corroding everything over time.

Here's the inside of an arm off a car that must have spent it's life in a wet area.

[kronus]

Had the steering arm zinced, put in new ball joints, and greased up the inside (used some bearing grease).

Dumb question - why does this area get greased? I did mine recently and didn't see any reason to do it...