5 Lug Conversion

[e21gangsta]

hey guys quick question. what all is entailed in the 5 lug conversion. what parts do i need and how much of a pain in the ass is it.
thanks
-jesse

[ATLBimmerkang88]

Great Question. I would like to knwo also.

[HE53]

I asked the same question in a thread yesterday...

e12 hubs

[e21gangsta]

Is That It Just The Hubs?

[Rickysbmw320i]

man, this is the third time it has come up in the last two days!

so i will help you out i guess!

from tricord...

and i believe this is just one way, theres more out there

Front hubs you can change to the front 5 bolt hubs from an e12. Not specifically the 535 as I have seen 528is with rear discs. The hubs fit the spindles on the e21. You have to check the bearings though as pre 80 models used different bearings that the post 80 models did. Caliper placement has been rumored not to change but then all the other guys that have done the mod have machined their own front hubs. Wheel offsets may change but then no one has actually provided details.
The idea behind using this type of subframe is all you have to do is shorten the front member down to the e21 size and weld the subframe mounting ears to this after you are done. I am not sure if any changes were made to the arms. From the pic they do not look like they have been changed. The end result bolts onto the stock subframe bushings. The difference between doing it this way rather than using an e30 subframe is that the springs are housed on the shocks on the e28 and are seperate on the e30. The e30 has a shock mounting point and behind it is the spring in its perch. The spring Top retainers have the same bolt pattern as the e21 and will bolt to the e21 rear towers. Not sure if you can mix and match these but the rear e28 springs are the same diameter as the e21 ones so... Plus you will bring over the bigger housing that accomodates the e30 e28 diff
Of course this is after measuring the centerline twice, making sure your geometry is correct, and cutting once. The rear calipers will plumb into the existing lines and work fine with the booster that is on the car already. If you did not have rear discs you have them now. The other addition is the rear mount for the e28 diff. You will have to make space for it and strengthen the floor of the trunk(boot) and bolt the e28 subframe mount
If you have a larger motor the added weight will be minimal as the motor will make up for it. Adding the diff will benefit the use of hard launches. But on a 4 cylinder or a M60/20 equipped car it will make the car heavy and will only be for looks. The "benefit" could be the added weight on the rear end making the car less tail happy but then who would really want to get rid of this?
A cheap "bastardized mod" could be integrating(read: heavy cutting and welding) the rear trailing arms from the same e28 and checking to see if the rear shocks mount up this way. Kind of easy to check the measurements and angles. Or if you are at a junkyard you can remove one trailing arm from an e28 and from an e21 and "swap" the e28 arm into the e21. Or at least measure the deficiencies, where you have to weld, how much farther apart the arm is, how much longer the arm is ect. At least giving you more ideas or more proof into the reality of modifying your BMW

hope that shows the amount of work involved

-rick

[e21Jason]

HI

E12 front hubs bolt on, you can use e24/28/34 front disks but you need fab up something for the brake calipers.

For the if you pull the rear arches you get way with a cut & shut e12 rear axle, or else narrow any other e24/28/34 axle or make your own rear hub, brakes what ever you can fit. it is easier to fit a wider axle than nrrow one. aldo all of the e24/28/30 diffs foul the reinforcement box section that goes along the rear of the sapre wheel well

Jason

[HE53]

HI

E12 front hubs bolt on, you can use e24/28/34 front disks but you need fab up something for the brake calipers.

For the if you pull the rear arches you get way with a cut & shut e12 rear axle, or else narrow any other e24/28/34 axle or make your own rear hub, brakes what ever you can fit. it is easier to fit a wider axle than nrrow one. aldo all of the e24/28/30 diffs foul the reinforcement box section that goes along the rear of the sapre wheel well

Jason

Wow, It would be pretty dang cool to have e34 brakes on an e21.

[e21gangsta]

thanks thats a pain in the ass

[vtgti]

thanks thats a pain in the ass

And I don't see any real benefit either???

[TheNeek]

And I don't see any real benefit either???

Only benefit is the bigger rear diff. It'd be easier to try and stuff that big rear diff in an E21 subframe. Not to mention the cost savings.

[blitzed310]

And I don't see any real benefit either???

Exactly. A whole lot of money and parts to put mordern wheels on?

[jjgbmw323]

they make spacers as well to convert 5 x 100 to 4 x 100.
I dont recommend spacers and I agree that this conversion is a major PITA for very little upside...5 lug on my car forgetaboutit.

I would rather spend the coin on getting wildwoods with two piece custom rotors under my 15 inch rims.

Alpina and BBS are the way to go on our cars.

[BruceH]

He can take the money saved and knife edge the crank...

[cheechthechi]

ouch.

[e21gangsta]

word!

[Kingoftarmac]

you can use e12 hubs/rotors on the early struts. if you turn down the rotor abour 2-3mm you can then use volvo calipers without having to slot them. also the e12 hub uses the same bearings as the 323i. Check it out

[milotrain]

But isn't more better?

[Kingoftarmac]

dont roll your eyes at me, Its a poor mans upgrade. how much will it cost to get 5-15mm larger rotors and have a caliper to fit? I did mine all for under 120 bucks.

[milotrain]

That's cool but I find that I outbrake my tires with my dinky solids and drums.

[Kingoftarmac]

i hear you milo, I forgot to add there is a m20 going in plus i did that brake conversion to settle a curiosity that i had. im going to add a bigger mc and some braided lines. the thing is i dont think im going to beat the hell out of this car once im done with it. I would feel really bad about wrecking a 2 year project

[jmitro]

i'm unclear.....can I use the E12 hubs on my later model (83) 320i struts/spindles? or does E12 hubs only work on early model struts/spindles?

[E21Adam]

only early

[jmitro]

anybody have any early spindles they want to sell?

[Layne]

I used 323i struts and e23 hubs and rotors. I'm pretty sure the hubs shown above are e23 as well. They're very heavy, but overall better than the e12 I think with the same size bearings. The front conversion is the easy part. No one ever talks about the rear.

[Beemer Tech]

has anyone ever made custom hubs that bolt up to the splines for the rear axles?