e30 makeover, what should I do?

So I've got a 1990 325i. Under 100k miles, very clean survivor with a spun bearing in the motor. I've also got a higher mileage 1988 325is automatic that's lived a fairly hard life, but the motor still makes good compression. I got both cars cheap, and intend to take all the good stuff off the older is and put it on the i. I'm just about ready to start stripping the is, and am sequencing the build. It occurs to me that when I've got the motor out of the i would be a good time to swap over the LSD, springs and do anything else that might be more difficult with a fully-loaded car. So I'm asking you guys what that list should consist of?

For sure: Clean and detail engine bay, springs.

Optional: New bushings, quicker ratio steering rack, what else?

Question: Anything that I should know on the bushing replacement? I want something firm, but not overly harsh or that will squeak.

Thanks for all responses!

• Re-do rear brake lines above the rear subframe
• rear subframe bushings to hard urethane or nylon
• Ireland engineering toe/camber adjustment for rear subframe
• 75+ durometer rear trailing arm bushings
• 4.10 LSD
• Ground control coilover kit w/ camber plates
• strut brace
• ST sway bars
• Treehouse racing front LCABs
• 2 18" summit racing glass packs in place of factory rear muffler (weld them together, and put nice tips on them in the same orientation as factory in the bumper lip).
• replace all the shifter bushings or purchase/fabricate a new shifter

In reply to kreb:

I probably wouldn't bother with the springs unless I was going to replace the front struts too. The rates are very similar and it might not be worth the effort. H&R sports and billies are a very popular option.

Definitely look into a quicker (Z3?) rack, it will be a snap with the engine out.

The LSD would be nice, but just make sure to check the tag for gear ratio to be sure it is something that you will like.

The control arm bushing are notoriously bad but doable since there are many write ups online. I am quickly becoming a fan of powerflex brand.

Definitely get good motor / trans mounts if you want them to last a good time. An upgrade diff bushing will also eliminate some drive line slop.

Also a great time to look into an electric fan conversion is you like that idea.

Replace the rear coolant hose that comes out of the back of the head; there is almost ZERO room to do this with the engine in the car!

I had my head apart recently and took some time to clean up the manifolds and gasket match the intake. Also clean out the ICV and other stuff while it is apart.

I did not have good luck with an adjustable cam gear recently but your mileage may differ if you want to retard it a little to shift power to the top end...

I am new to e30's so maybe some real experts will chime in; good luck!

Yeah, Listen to GPS... he is one of those experts I was thinking of...

Giant Purple Snorklewacker wrote: - Re-do rear brake lines above the rear subframe - rear subframe bushings to hard urethane or nylon - Ireland engineering toe/camber adjustment for rear subframe - 75+ durometer rear trailing arm bushings - 4.10 LSD - Ground control coilover kit w/ camber plates - strut brace - ST sway bars - Treehouse racing front LCABs - 2 18" summit racing glass packs in place of factory rear muffler (weld them together, and put nice tips on them in the same orientation as factory in the bumper lip). - replace all the shifter bushings or purchase/fabricate a new shifter

The only thing I add, not because it's really necessary but because you have everything apart.

Hubs front, bearings rear, reinforce the rear sway tab mount points, rebuild the brake calipers and paint/powdercoat, stainless steel lines, fresh pads/rotors. I would also do an E36 steering rack like you mentioned, timing belt/water pump/dizzy and all seals when swapping the motor.

Then enjoy another 200k trouble free miles.

Wow! I think that some of those items will be on the longer-term list.

A little more background: The knucklehead previous owner put some lowering springs on the car which were pretty soft, so while you get the benefit of a lower cg, the springs are softer than stock is ones, and it resulted in the oil pan being taken out and the subsequent spun bearings. This car is meant as a fun 2nd vehicle that I can occasionally autocross with no particular class in mind. I don't want to make it too harsh, and think that I'd like to maintain stock, or close to stock ride height. Question: with stock spring rates, does it make sense to beef up on aftermarket sway bars?

tb wrote: Definitely look into a quicker (Z3?) rack, it will be a snap with the engine out.

+1

Wait, +6.02 * 10^23

Let's just say I agree wholeheartedly...

And yes, aftermarket sway bars will mitigate some of the roll from the soft stock springs.

In reply to kreb:

The stock E30 springs are pretty tall and soft even on the 'is' but if you don't want to lower the car at all - then beefier bars will help keep sea sickness at bay when autocrossing. An E36 M3 or Z3 (4 cyl) rack will also be a huge improvement. If you don't do anything else on the list ... find a 4.10 diff. You can sell your 3.73LSD for even money to the SE30 crowd.

oh.. and z31 is right - do the rear wheel bearings while the rear is off the car if they need doing. They can be a real son-of-a-bitch and being able to use a hydraulic press will absolutely make it easier. If yours are low miles though... under 100k there is no reason to suspect them. The OE ones on my old DD e30 were original at 212k and fine.

kreb wrote: Wow! I think that some of those items will be on the longer-term list. A little more background: The knucklehead previous owner put some lowering springs on the car which were pretty soft, so while you get the benefit of a lower cg, the springs are softer than stock is ones, and it resulted in the oil pan being taken out and the subsequent spun bearings. This car is meant as a fun 2nd vehicle that I can occasionally autocross with no particular class in mind. I don't want to make it too harsh, and think that I'd like to maintain stock, or close to stock ride height. Question: with stock spring rates, does it make sense to beef up on aftermarket sway bars?

I'd really consider a proper a spring/shock/sway setup to make it enjoyable.

Basically, but the Spec E30 setup. It's not to harsh for the road buy will up the handling without going to crazy spring rates like I did on my coilovers.

z31maniac wrote: I'd really consider a proper a spring/shock/sway setup to make it enjoyable. Basically, but the Spec E30 setup. It's not to harsh for the road buy will up the handling without going to crazy spring rates like I did on my coilovers.

The spec e30 kits seem to be a real bargain, and I've read racers say that the spring rates are surprisingly soft for race applications. That makes me wonder that it might be OK for the street. But again, I don't want it too low. Perhaps spece30 plus spacers?

Another Q: I spoke with an autocrosser who'd added the 4.1 LSD, and he told me that while it woke up the engine, it actually made him slower in autocross because he'd have to shift more often. Anyone else had that experience? And will the 4.1 raise the revs to where freeway cruising is less pleasant?

kreb wrote: The spec e30 kits seem to be a real bargain, and I've read racers say that the spring rates are surprisingly soft for rce applications. That makes me wonder that it might be OK for the street. But again, I don't want it too low. Perhaps spece30 plus spacers?

I ran it on the street. Cheap and effective... It isn't that low actually but I also ran a home-made undertray because even normal ride height E30s have that conspicuous bit of oil pan out front.

If you do it - consider the Ireland or AKG adjusters on the rear subframe as you will get a lot of camber from a little lowering and some "interesting" transitional properties from trailing arm articulation that messes with the toe as a result. The adjusters allow enough to return to factory settings from the SE30 kit. You can also use thicker rubber pads under the rear springs to trim the rake a little.

Oh yeah, what about a baffled oil pan? I've seen kits that go between the block and the pan. Are there starvation issues on the e30s?

kreb wrote:

z31maniac wrote: I'd really consider a proper a spring/shock/sway setup to make it enjoyable. Basically, but the Spec E30 setup. It's not to harsh for the road buy will up the handling without going to crazy spring rates like I did on my coilovers.

The spec e30 kits seem to be a real bargain, and I've read racers say that the spring rates are surprisingly soft for race applications. That makes me wonder that it might be OK for the street. But again, I don't want it too low. Perhaps spece30 plus spacers?

I think the rates are something like 315/570. I wouldn't want to go any softer actually.

On my S52 swap car I ran 550/750 on my Ground Controls with custom valved Konis..........it was amazing buy stiff. I also ran it this low with no problems.

215/40/17 on Work Wheels......miss that car too.

kreb wrote: Another Q: I spoke with an autocrosser who'd added the 4.1 LSD, and he told me that while it woke up the engine, it actually made him slower in autocross because he'd have to shift more often. Anyone else had that experience? And will the 4.1 raise the revs to where freeway cruising is less pleasant?

It might make you shift more 2-3 around the cones... I don't really auto-x at all since going w2w racing so I wouldn't be able to answer whether it was something you could overcome with the extra acceleration and a little grip but ... I can theorize :) . I had a chip that raised revs so I didn't notice any additional problems getting caught between gears on the track - it helped lap time. For me - it made the car a lot more fun and responsive as a DD. It does raise hwy revs obviously - but the DD mileage stayed right at 25mpg as it always was.

Yeah, stock is 3.73 so you're only raising the revs by ~11%

I liked it when I still had the M20 in the car, but I never auto-x

Maybe I'm old but fwiw, I'm no longer particularly fond of poly bushings for suspension. They transmit more NVH than I like. Feels great at first but got tiresome with age.

PURDY!

I had a 325ix with an automatic transmission, and those cars came with 4.10 gears in the differentials. It was s-l-o-w...the steep gears combined with the shift points in the automatic transmission just didn't work very well for spirited driving, it would shift up to the next gear too soon. I don't think I ever saw more than 3500 rpm when driving that car.

kreb wrote: Another Q: I spoke with an autocrosser who'd added the 4.1 LSD, and he told me that while it woke up the engine, it actually made him slower in autocross because he'd have to shift more often. Anyone else had that experience? And will the 4.1 raise the revs to where freeway cruising is less pleasant?

If auto-x is the main focus, then even a 3.73 is too short. At least for the typically 60 mph courses my region likes to design. Especially if running commonly available 15" ST tires (which are a bit smaller than the stock 24" dia) but even with 24" tires 2nd gear was limiting and the E30 shifter design is far too crappy to risk a high-rev 2-3 shift under load multiple times during a 60 sec run. I was considering a change to 17" wheels mainly so I could get taller tires to help the gearing, but even then decided I was just trying to make the car into something it could never be (hence why it's for sale).

If you do it - consider the Ireland or AKG adjusters on the rear subframe as you will get a lot of camber from a little lowering and some "interesting" transitional properties from trailing arm articulation that messes with the toe as a result. The adjusters allow enough to return to factory settings from the SE30 kit. You can also use thicker rubber pads under the rear springs to trim the rake a little.

Condor Speed Shop (GRM Challenge e30 widebody car guys) makes some nifty subframe spacers to combat the camber without needing the weld-in alignment stuff.

Spec E30 guy here who occasionally drives it on the street "for testing purposes". My opinions are, well, opinions and won't agree with some of the other E30ists.

I will recommend the SE30 suspension package. These cars are way to tall from the factory (methinks to meet the bumper height rules). The H&Rs are firm but not hateful. Same with the Bilsteins. Ireland sway bars reportedly fit a little nicer than the ST bars and I've been happy with mine. ABSOLUTELY get all the reinforcements for the sway bar attachments, including the weld on tabs for the rear control arm mounts. Not hard to weld on for even an idiot welder like myself and those tabs WILL bend without them.

I have poly bushings pretty much everywhere and don't mind them, though I didn't bother with the diff bushing as it seemed like a lot of money for something that isn't causing me any trouble. Poly engine mounts, too, because I broke one of the flimsy-ass rubber ones autocrossing (granted, they were probably original).

My only shifter mod was a Z3 shift lever. It solved all my sloppy feel issues. Very short and notchy shifts, but you get used to it.

I'll never, ever remove the rear subframe myself again. What a colossal PITA. But you have to to replace the brake hoses. Braided FTW.

I bought Ireland camber plates for the front but don't like them. I'd get Ground Control if I bought again. The Ireland ones are just kind of hokey. I refuse to install adjusters in the rear because pretty much everyone I race with who added those has had problems with them getting lose, often in very unhappy ways. I'll take the alignment I get and deal with it and finish races vs risking stuff coming apart.

Cherry bomb mufflers, yes. Or just have a piece made to make it all one pipe out the back; probably cheaper.

Strut brace...meh. Have one, don't use it. But then my car has a cage welded into it.

Stock brakes are totally adequate, just buy good pads.

Ditch the clutch fan and just rewire the a/c fan to run either manually (you can do it with the snowflake button as-is) or from a thermostat. Works fine for me. BMW does make brackets to mount the fan by itself if you yank the a/c.

Offset lower control arm bushings for the front if it's lowered. Drill and add a set screw so they don't twist in the lollipop.

With the spec suspension, the car is an absolute beast on an autocross course. It's like driving a MINI or similar; just point and hit the gas. You'll definitely want a better than stock seat so you don't go flying around the interior.

ddavidv wrote: My only shifter mod was a Z3 shift lever. It solved all my sloppy feel issues. Very short and notchy shifts, but you get used to it.

Short, notchy and still floppy. Waste of time, IMHO. Of the many things that piss me off about the E30, the crappy shifter ranks near the top.

I don't care what suspension you put under an E30, it won't be a MINI on an autocross course.

Thanks for reminding me why I hate that berking car...

ddavidv wrote: I refuse to install adjusters in the rear because pretty much everyone I race with who added those has had problems with them getting lose, often in very unhappy ways. I'll take the alignment I get and deal with it and finish races vs risking stuff coming apart.

They have new ones that don't come loose. They have grids like adjustable hitches.

http://www.iemotorsport.com/bmw/E30-suspension-steering/adjtoekit-lock.html