E30 Rally Car

I've gone and bought this:

1991 318is.  The last thing it did was the Mt. Washington Hill Climb in 2017.  I basically bought it sight-unseen, because it was in New Hampshire, and by the time I drove all the way out there from Colorado with a trailer, I wasn't really in a position to negotiate or walk away.  I hope it wasn't a terrible mistake.

A little background: I identify as a Miata guy who races a Formula Vee.  A fellow Vee driver has a lot of experience rally co-driving, and I asked him how to get into it.  "Buy a car, put a cage in it, go do it."  "What car?"  "A cheap one.  You're going to crash it into a tree."  He's agreed to co-drive for me, so I at least won't be going into it completely blind.  And while I do have a habit of driving the Vee sideways and in the grass, I don't have a lot of relevant experience.  I'd love to make it to Rally Colorado this year, but it sounds questionable whether that's going to happen this year.  If not, I'll figure where I can go instead.  I'll probably try to do some Colorado hill climbs first.

After doing a little internet research I decided that I really didn't want to build a car to start.  I've been building an airplane for 8 years now and I'm never going to finish it if I start building a rally car.  There aren't a lot of affordable rally cars for sale.  I have a rule about not buying FWD cars, so there weren't a lot of options and this popped up at the right time.

After doing a bunch of internet searching, it seems there's a lot of good relevant information here so I'm hoping for some good advice.  I'm completely new to BMWs of any sort.  I spent a day reading much of irish44j's build, but it would probably take me a week to get through all 130 pages, and there doesn't appear to be a thread search option, so if I ask something already covered there I'm sorry.

The car has an old SCCA logbook.  The cage appears to be an actual rally build, tied into the suspension.  Unfortunately, it's 1.5 x 0.095 tubing, so it does not qualify for a new ARA logbook.  I did e-mail Doug Nagy before purchasing the car who assured me that the car can run in ARA as long as I add a sill bar and windshield brace bars.  After getting it, it appears that it actually has sill bars, they're just so low they didn't show up in the pictures.  I know the car will also need fire suppression, but that should be pretty simple to do.

First up is fixing the broken things and going through everything that *might* be broken.  A quick drive through the neighborhood reveals that the car mostly works.  Only one rear brake started smoldering!  It makes a ton of noise without the side effect of any real horsepower.  The diff is welded.  It has hotbits rally suspension, but is currently set up on tarmac tires and lowered because the Mt. Washington hillclimb was its last event. 

The car came with 5 compomotive rally wheels and 6 Pirelli gravel tires.  The tires are very old, and I have no idea how to judge how much life is left in gravel tires even if they weren't ancient?  I assume I need at least one more spare rally wheel? The tires are left/right--how does this work with only a single spare wheel on board?  If you have a flat on stage and it's on the wrong side, do you just run one backwards until the next service?
 

Some questionable things.  First, the radiator mounting:

I'm not sure, but zip ties strike me as a sub-optimal radiator mounting method.  Given that I have no idea what this is supposed to look like, what's going on here?  Is this the wrong radiator?  Are there mounts missing?

 

The kill switch does absolutely nothing.  After pulling the panel and looking behind it, the reason why was pretty clear:

This is baffling to me on so many levels.  (1) Why install a kill switch, but never connect it?  The 0 AWG wiring from the battery to the connector on the firewall looks pretty stock and unmolested to me, so I'm thinking was never connected.  (2) How has this car gotten through tech?  Did RA not require kill switches?

ARA sure does:
2.2.5 Master Electrical Disconnect Switch
a) A spark-proof master electrical disconnect switch with the capability of
disconnecting all electrical circuits shall be mounted in the passenger compartment.
(The integrity of a fuel injection computer may be protected by supplementary
wiring.)
b) The location of the master electrical disconnect switch shall be that which makes it
easily operable by either crew member or by persons outside the vehicle through 
2021 Edition 6 ARA Rally Technical Rules
either front door and shall be marked with a label showing a red spark in a white edged blue triangle with a base length of at least 4 inches.
c) The switch must effectively shut down all systems including alternator and engine

As far as I can tell, there's not even currently a method to make sure everything's disconnected.  With the switch labeled "ignition" off, most things are off, but the voltmeter still reads 12V and the battery is dead in a few days if I don't disconnect it. 

So, given those rules, my plan is to install a 300amp continuous duty solenoid at the battery and wire it to a dual-pole toggle switch with the ignition wire.  The solenoid is cheap ($19), and this way I don't have to deal with re-routing a bunch of 0AWG wiring.  And presumably killing the ignition wire to the ECU at the same time also kills the field wire to the alternator.  This also has the added advantage of being able to kill the fuel pump wiring as well.  Because the fuel pumps are wired directly to the battery:

(Yes, I also need to clean up all that gunk.  It's some kind of dirt/mold, doesn't appear to be corrosion as it cleans off.)

That brings me to the fuel pump situation.  Appears to be a redundant dual fuel pump setup.  Both fuel pumps and relays work, but only one switch works at the moment.  I think there's a break in the switch wire somewhere.  Each fuel pump is wired through its own circuit breaker, though one is 10A and the other is 20A, because consistency?

Both fuel pumps are also routed through a single relay whose purpose took me awhile to suss out.  That relay is connected to an oil pressure switch...through a toggle switch.  So the idea seems to be that in the event of a loss of oil pressure, the oil pressure switch will kill the fuel pumps, thus saving the engine.  The toggle switch lets you bypass the oil pressure switch so you can power the fuel pumps with no oil pressure, presumably so you can start the car. This all sounds great in theory, but I've got some real problems with it.

(1) You've gone through all the trouble of having dual pumps with separate wiring and relays and switches, but you're going to have a single wire to a oil pressure switch be a common point of failure?

(2) I'm trying to imagine the scenario where you're bombing down a rally stage, lose oil pressure and this thing triggers, thus saving your engine.  How long does it take you to figure out this happened?  And once you figure out it's the oil pressure switch, how do you figure out if the problem is the switch or if you actually had low oil pressure?  How much engine damage do you do before you figure that out?

(3) What are the chances you actually remember to turn off the bypass after starting the car?

Oh, also there's an oil pressure gauge that doesn't work, because:

The brass thing there is the mechanical oil pressure sender to the gauge.  The wire connected to the switch on the housing goes to that fuel pump relay.

So, what to do here?  Just, ugh.  While the oil pressure safety switch is an okay idea, I'd far rather have both an oil pressure gauge AND an idiot light.  A very large idiot light.  I also hate mechanical oil pressure gauges that involve routing oil through thin plastic tubing all the way to gauge.  Because that tube is going to break, which will result in first an indication of 0 oil pressure, but if you don't notice it, eventually actually 0 oil pressure as the entire contents of your crankcase are pumped out of the little tube.

I think I want an electrical unit that has two connectors--one for an idiot light at 7-10PSI, and another for an electrical gauge.  Which is what I have on my Vee.  Presumably I can find something that plugs up to an M42.

Looks like a cool car!

VDO  makes a sender with the right thread for your port, a switch for the light and an output for a VDO gauge with the proper range to match the sender. Having said that, the VDO gauge will be so dampened that to me it seemed only slightly better than an oil light as it took so long to react to any changes.

adam525i said:

Looks like a cool car!

VDO  makes a sender with the right thread for your port, a switch for the light and an output for a VDO gauge with the proper range to match the sender. Having said that, the VDO gauge will be so dampened that to me it seemed only slightly better than an oil light as it took so long to react to any changes.

Rats.  The one in my Vee is VDO and it's probably underdamped.  It's also probably 40 years old.  I'll see what else is out there.  I'm guessing with the right adapters any universal solution should work.

This looks like the easy solution: https://www.bimmerworld.com/Gauges-Data-Acquisition/Data_Gauge_Accessories/BimmerWorld-Oil-Distribution-Sending-Block.html

But geeze that's a lot of money for a threaded hunk of metal.

Nice, I was wondering who bought that thing (I tried to get my codriver to buy it, actually). 

There are several e30 rally build threads on this forum (mine is about 2000 posts long and is here: https://grassrootsmotorsports.com/forum/grm/mein-e30-mein-sammlungkreuz-baugewinde-my-318i-rallycross-build-thread/40440/page1/), and Dan Downey and a few others are on here as well, so worth reading up as I think between us, we've documented a LOT of things that you'll want to know about running an e30 (my actual stage rally build starts a couple years into my thread, but lots of prep stuff in the "rallycross" years as well).

As to a couple of the things you posted:

1. I wouldn't worry too much about the fan, honestly. There are lower mounts that hold it in place, so the zipties are just keeping it from tipping back. Mine has rubber spacers with bolts thrhough them doing the same thing (to that little lip on the upper core support). That said, you may want to look into upgrading to an aluminum radiator. The M42 rad with the integrated overflow tank has a tendency to crack and leak (ask me how I know). When I had the M42 in my car, I converted over to an e36 M3 radiator with a separate M20 (6cyl e30) expansion tank mounted on the fender and haven't had any problems (still hvae the same setup with my current M50). There is a plastic factory piece that goes on top stock, with two rubber bumpers, but honestly it's garbage and I threw mine out long ago.

2. RA did not require a kill switch, nor did ARA until last year (or the year before, I forget).

3. That oil presssure switch to fuel pump thing is wonky, I don't get it. Just get a big red warning light for oil pressure. We broke our oil pan at NEFR and my warning light came on within 5 seconds and we shut it down and saved the engine. 

4. LUCKILY for you, the M42 oil filter housing has a SECOND pressure switch location on the front side (look down between the belts). So you can run a gauge pressure sender from one and a warning light switch from the other (it's in my thread if you look around enough).  Use the stock dummy light switch for a light, and get a VDO sender (electic) and gauge for it. Again, documented all this stuff in my thread if you have a few hours to read lol...

if you're on facebook, look up "dirty e-thirties," that's our group and it's pretty large. Not all that active these days, but there are plenty of people in that group that can answer basically any questions you might have. There's another 'BMW Rallying" group as well, but lots of e36 guys in there as well so it's not as focused. 

Since I happen to have an M42 sitting in my garage for another project....here's a photo of the second sender location....

I think this is the only BMW engine with this second port (my M50 doesn't have one), so you're in luck. For my M50 I have to use a double-port adaptor like the one you posted above (btw, you can get them way cheaper on ebay, no-name version). 

side note, that's an interesting cage for the cell. Somewhat amusing they left half the spare well there. Still don't really understand why bother putting a fuel cell in an e30. The stock tank is in a better location for weight distribution and though I 've dented mine on an extremely large rock (which also mashed up my rocker and codriver's floor), it's not particularly vulnerable in stock form, especially with a good HDPE sheet for armor below it. 

Also, this being a new england car, closely check the lower mount of the gas pedal to make sure it's still attached ot the floor. That spot rusts out on almost every e30 I've ever seen (even southern cars) and then the pedal comes detached at the bottom. I'm actually just repairing that spot in my current e30 project (it was also done on the rally car). 

Thanks!  The second oil port location is exactly the sort of thing that I'd never have found on my own.  I really need to spend more time with your thread.  I read a few hundred posts, skipped to where you put the cage in it, read a few hundred more, then got distracted with Nonack's BRZ thread which won't really help me at all...

I wouldn't have put the fuel cell in if I were building it.  This side of the Pinto, I think manufacturers do a pretty good job of fuel tank location and protection.  SCCA might have required it back when this was built?  Hard to imagine requiring a fuel cell but not a kill switch, though?  Certainly not going to mess with it until the foam disintegrates.  Which it might already be given that it's probably been running with ethanol fuel and non-ethanol-compatible foam.  I guess I should pull the fuel filter and cut it apart.  Sigh.

I am on Facebook, begrudgingly, but I hate it for this sort of thing because (1) the thread interface is terrible, and (2) the groups are private so Google doesn't index the threads, so knowledge sharing there just disappears.  But I'll join your group:)

The gas pedal is still attached the floor, but there's some diamond plate bolted on top of the floors, so it's hard to see what's going on down there.  Good reminder to pull that and investigate.

Lol. Yeah hopefully it being a rally car the previous owner already took care of that gas pedal problem since it probably would have happened a decade ago or more...

Point taken on the fuel cell, It was more of a observation than a suggestion to replace it! If you do decide to switch back brand new oem type gas tanks are very cheap on RockAuto. At least for the smaller 318 tank. I think I got one for like 150 bucks last year.

The only ventilation in the car is the stock blower motor.  Which sounds like it's full of acorns and smells terrible.  It was pretty obvious why once I took the cover off:

Whatever nested in there apparently liked the wiper motor wiring as well:

After hours of cleaning and scraping and vacuuming, I managed to get the nest cleaned up.  The blower motor ran great for about 20 seconds, then seized.  So I guess I'll need to replace it? Or is there a better option for defog?

I'm a little confused by what's going on with the climate control system.  All of the cables have been removed.  The stock center dash vents are still in place.  The outer vents are removed and the ducting that went to them has been duct taped.  Always nice to see duct tape on ducts!

The blower motor control is intact and there are 2 wires connected to the temperature knob.  I think the temperature knob was probably supposed to have a cable or something as well?  Not sure, but there's just 2 very small wires.  Not sure if this is enough to move some servo to get heat?  The heater core appears to be intact and there's plumbing going to it.

All in all this is a bit surprising and seems somewhat insuffficient.  Every photo of a rally car I'm looking at has a hood scoop, but mine doesn't.  It seems like this means I should add one?

I spent awhile removing decals.  rallycarparts.com, whatever it is, no longer exists, so I guess I don't need to keep advertising for them.

Josh-- I tried to join your facebook group, but no group appeared with that name.

Berck said:

The only ventilation in the car is the stock blower motor.  Which sounds like it's full of acorns and smells terrible.  It was pretty obvious why once I took the cover off:

 

 

Whatever nested in there apparently liked the wiper motor wiring as well:

 

After hours of cleaning and scraping and vacuuming, I managed to get the nest cleaned up.  The blower motor ran great for about 20 seconds, then seized.  So I guess I'll need to replace it? Or is there a better option for defog?

I'm a little confused by what's going on with the climate control system.  All of the cables have been removed.  The stock center dash vents are still in place.  The outer vents are removed and the ducting that went to them has been duct taped.  Always nice to see duct tape on ducts!

The blower motor control is intact and there are 2 wires connected to the temperature knob.  I think the temperature knob was probably supposed to have a cable or something as well?  Not sure, but there's just 2 very small wires.  Not sure if this is enough to move some servo to get heat?  The heater core appears to be intact and there's plumbing going to it.

All in all this is a bit surprising and seems somewhat insuffficient.  Every photo of a rally car I'm looking at has a hood scoop, but mine doesn't.  It seems like this means I should add one?

I spent awhile removing decals.  rallycarparts.com, whatever it is, no longer exists, so I guess I don't need to keep advertising for them.

Josh-- I tried to join your facebook group, but no group appeared with that name.

I ended up swapping to a Summit Racing header/fan setup that bolts under the firewall basically to the bottom of the opening where the stock fan/HVAC goes (after my stock heater core exploded during a rallycross and doused me with hot coolant). The e30 blowers (like all old German cars) get noisy and then seize, You can rebuild to some degree and they'll go for a while longer sometimes. I just ripped all the stock HVAC stuff out and got something like this:

https://www.jegs.com/i/JEGS+Performance+Products/555/70602/10002/-1?gclid=Cj0KCQiA5aWOBhDMARIsAIXLlkcolXRjutkQ9OLn7-RzqxoLqJDsjzkKLL41bIxYQOdxXxaptN0IMfAaAur5EALw_wcB

Mine has two outlet ports, but I think the 3-port one would fit and wish I had done that instead....

You mean a roof scoop?

Here's a direct link to the group: https://www.facebook.com/groups/449866455034268

Roof scoop, yes.  Words hard.  The two previous drivers weren't bothered enough to add one.  The car is going to have to live outside so I'm worried about adding more leaks.

I'll look for that heater/fan install in your thread.  My heater core isn't leaking yet, but it's probably original and probably a matter of time.  It looks like there's no option to have air without heat?  Maybe you just add a heater valve?  Or if it's just for defog and heat, you assume that heat with the defog is a good thing?  My current race car doesn't have a windshield and the defog option is "drive faster" so this is new stuff for me:)

Yeah, heat for defog. If i ever build another rally car, I'll keep functional A/C but that ship has sailed for me. 

I haven't had any roof vent leaking issues. I use one of the standard RV vents that most budget teams use, and it's sealed up generously with silicone. The roof vent is less for keeping you cool than it is for positive pressure into the cabin to keep dust from coming in through door seals and stuff like that. I also have NACA ducts in the rear windows but haven't ever bothered to run hoses from them.

For the heater install I basically just made a plate to cover the OEM fan opening there and bolted the heater to it. If I remember correctly, it just pulls recirc air from the cabin to heat, since I didn't want it sucking in dusty air and pumping it into the cabin. 

Great start to your thread!  Where in CO are you?  I'm currently getting my e30 sorted out to run with CHCA this season and eventually ARA but probably not for a couple years. 

In reply to Crenshaw :

I'm in Divide (in the mountains west of Colorado Springs).  I'm definitely planning on CHCA to start--waiting to see what the schedule is and which events will conflict with RMVR, as RMVR events will take priority.  I don't really know anything about any of the CHCA events, but Monarch is pretty close...

In reply to Berck :

Sweet!  I'm in Salida.  CHCA is a great group of people, pretty relaxed but safe atmosphere and the courses are epic.  The Temple Canyon event is outside of Canon City, right in your neck of the woods.  They generally run Monarch twice- once in the spring and once in the fall.  Land's End is great too, just SE of Grand Junction. 

Is the rad missing the lower mounts (3,4,5) as well as the upper? (6,7) Kind of looks like the rad might be hanging from those zipties...

You can run directional tires backwards with only a small degradation in performance.  You might not even notice it.

Running them inside out, at least for the old Michelin tires that most asymmetrical directional designs are based on, will wreck them.  Backwards is better than inside out.

iansane said:

 

Is the rad missing the lower mounts (3,4,5) as well as the upper? (6,7) Kind of looks like the rad might be hanging from those zipties...

As far as I can tell, it's zip ties all the way down.

Unclear why the stock mounts were abandoned?

Suspension questions... I was told the car was currently lowered for tarmac.  It has hotbits dampers all around.  Adjusting the height on the coilovers in the front is simple enough (It's currently set as low as it'll go).  The rear has some red springs installed, but the boxes of spares contained some silver-colored springs that say hotbits on them.

Not sure about the relative spring rates, but the hotbits springs are substantially shorter.  So short that at full droop I can remove the springs even with the shocks attached:

That seems bad.  Am I missing something?

The oil pan is covered in oil and slightly dented.  I'm not worried about the dent, should I be?

The oil goes all the way up to the valve cover gasket.  So I'm pretty sure the valve cover gasket is leaking, but it seems unlikely that's all that's leaking.

Given how long the car sat, I'm not really surprised about some oil leaks.  I guess I'll replace the valve cover gasket and see how much it improves.

Berck said:

Suspension questions... I was told the car was currently lowered for tarmac.  It has hotbits dampers all around.  Adjusting the height on the coilovers in the front is simple enough (It's currently set as low as it'll go).  The rear has some red springs installed, but the boxes of spares contained some silver-colored springs that say hotbits on them.

Not sure about the relative spring rates, but the hotbits springs are substantially shorter.  So short that at full droop I can remove the springs even with the shocks attached:

That seems bad.  Am I missing something?

Yeah you definitely don't want the springs to be able to fall out at full of droop. I have had that happen during a rally and it ended the rally.... Of course in my case both of my shocks sheared off so that was absolutely nothing holding the controller arms up lol

Berck said:

The oil pan is covered in oil and slightly dented.  I'm not worried about the dent, should I be?

The oil goes all the way up to the valve cover gasket.  So I'm pretty sure the valve cover gasket is leaking, but it seems unlikely that's all that's leaking.

Given how long the car sat, I'm not really surprised about some oil leaks.  I guess I'll replace the valve cover gasket and see how much it improves.

That is standard operating procedure for M42 even after rebuilding and resealing. I think some of the leaking comes from the timing chain tensioner which is that little plug-shaped thing on the side. I also used to get a lot of leaks from the sensor that plugs in right above the water outlet near the top of the front.