|Be Mah Baby. Part 1 (approx 2007/8)
My gorgeous misses, Diana, has always wanted to go racing in a BMW E30,
which makes her really rather sound, but we are always skint, sound familiar?
Not only that but I am starting a new business and don’t expect
to have any income for a few months, I am moving to a bigger workshop
and fitting it out, plus we are renovating the house extensively. If that
wasn’t enough, for a grand finale we are having a baby! But petrol
is in our blood.
So here is the plan; I will make her a track car in secret and give it
to her when she gets back from delivering our sprog in hospital! Then
do some further mods over winter so she can race in the CSCC Future Classics
series next year. What a plan!
A sound 325 2 door non-sunroof car is both rare and way above my three
figure budget, but I have a cunning plan; all I have to do is buy a good
2 door 316 non sunroof shell, a rusty but mechanically sound 325i, a suspension
kit, some wheels and tyres, make an exhaust, get a FIA approved roll cage,
fire extinguisher, race seat, harness etc. All in secret and with no money.
What can possibly go wrong?
The splendid thing about the E30 is how easy it is to make a fairly swift
racer, the shell is a good compromise between strength and lightness,
the engine is robust and tuneable and of course the suspension is legendary.
So the basic concept is to strip as much weight out as possible, tricky
as there is not much excess on there to start with, but hopefully I can
get about 200 kg out including stripping the heater out and removing the
The engine will be properly serviced, which may restore as much as 20%
power loss that a poorly serviced engine may suffer. Then it will get
a sports air filter in the standard air box, which is actually quite a
good design, and spark plugs of one grade colder in order to cope with
the heat of a race. I am hoping for about 180 bhp but importantly it should
The exhaust will be cut short and directed out the side, to save weight
and lower back pressure a little.
Standard brakes will have to do to start with, but with racing pads and
fluid plus a strip down and rebuild.
The suspension responds well to lowering as the rear arms increase camber
as they go up, I am going to start with a 40mm drop at the rear and 60
at the front so that it is slightly nose down to improve downforce at
The interior will get the usual treatment, roll cage, fire system, race
seat and harness. For now I will keep the standard side glass and electric
widows, going plastic only saves a few kilos but costs hundreds.
The tricky thing will be finding suitable tyres, lowish profile with reasonable
grip, within the budget.
So I start the search, I get a ‘feel’ from cars in adverts,
loads seemed to meet the spec but didn’t ‘feel’ right.
I didn’t know what I was waiting for really, then it dawned on me;
loads of people must have tried this two cars into one trick and got stuck
at some point, so an unfinished project (as it were, a boxed set) would
surely turn up sooner or later. Well, I searched and searched, local ads,
exchange and mart, autotrader, web sites, until one day in march I saw
the perfect ad: E30 316 with mot, 325i partially disassembled, 8 Alpina
style wheels and tyres, suspension kit, all must go as space needed. A
bargain at just over £800.
Dan the man, who was selling this lot, had much the same idea as me when
he bought the cars. A dyed in the wool BMW fan, he has had a number of
classic beemers and currently sports a rather natty 5 series. He was quite
clearly gutted to have to abandon the project, but the rental in the container
and time constraints meant that he was effectively paying for nothing
on a monthly basis.
It was a beautiful Tuesday when I went to pick it up, it wasn’t
till I had the 325 on the trailer that I realised how long it was and
a good half hour was spent finding a way to lash it down. Then came the
job of getting 8 wheels, 9 tyres, a suspension kit and a spare interior
that I don’t need into the back of my Discovery.
Once back at the bat cave, secrecy was essential so I asked my neighbour
to store the car in his shed and stacked the wheels up in my workshop
under cover. Job done for phase 1. Of course things are never as good
as they seem, and in this case the suspension kit turned out to be a No
Name brand bought cheap on the interweb, time will tell if it is any use
but the fall-back plan is to cut enough off the springs to drop the ride
height to the same level as the PBMW racers and fit good adjustable dampers.
The wheels are un branded too and the tyres are a fairly cheap brand so
I expect to upgrade later, but the first stage is getting the car running
and on a track day and as they appear to be round they will have to do.
Time to clear some of the unwanted crud out of the way; on Ebay you can
look at completed listings, and a quick scan showed that there is a vigorous
market for E30 bits. Amazingly the leather interior with holes in went
for over £100, and once the standard wheels, bits of dash and a
spoiler had gone I was pleasantly surprised to have recovered about £250.
The exhaust is a twin pipe set up with one box just behind the gearbox
and a big heavy one behind the rear axle, my thought is to retain the
first box and ditch the rest of the system and direct the twin pipes out
the side just ahead of the rear wheel, should be nicely fruity and more
importantly save a fair bit of weight.
After removing the engine with all relevant wiring including the fuse
box plus the oil cooler, radiator, exhaust (which was a cheap attempt
at a sports system) and prop shaft, I turned my attention to the back
end and took out the whole rear axle assembly which has disc brakes (the
316 has drums). It occurred to me that racing tends to bend the corners
of cars so I took the front wings, lights and bumpers too, leaving a very
By luck I took the scrap shell down to the metal merchants yard at the
height of the scrap prices and got over 50 quid, it must be a sign...
At this point I still had to pick up the 316, still parked outside Dans
house 30 miles away, but I would sort that tomorrow. Time for tea.
Back home Dianna greets me with the news that her uncle has offered to
sell us his house at a very reasonable cost, we just need all our savings
including the money I have secretly spent on two cars! The word bugger
springs to mind.
The following day things get slightly more complicated when she makes
a surprise visit to the workshop.....
The CSCC Future Classics series is basically a silhouette formula, where
the car must look the same as a standard car in profile, the engine must
be in roughly the same place and the driven axle must be at the same end
as standard, but almost anything else can be modified to your hearts content.
Traditionally silhouette series are very expensive, with thing like a
Lola F1 car sporting a fibre glass replica of a Hilman Imp body glued
on, but the CSCC is very different, they moderate entries to ensure that
it’s accessible to the average racer on a tight budget and that
the racing is close and fun. It’s a winning formula.
As far as this car is concerned, it means I can tune the car with an angle
grinder, which is very cheap! Things like the boot floor can be removed
and replaced with a nice flat sheet of ally, and the complex parcel shelf
and rear seat back can be cut out and replaced with flat steel sheet that
will integrate with the roll cage to give a very stiff structure that
wont have any holes in that could let fuel tank fumes into the cabin.
I thought I was getting away with it but as she was about to leave she
caught a glimpse of the covered 325 next door, and although it was draped
in old blankets and piled with boxes on top as a disguise, she managed
to identify the curve of the front headlight cowl under an old duvet!
‘Is that an E30? Why has Stuart got an E30, he drives tractors?’
Immediately I try to set her mind at ease by saying ‘eeeeerm, ahhh,
uh’, at which point she looks me right in the eye and says ‘is
that yours?’. Bugger, caught.
As I explain my crackpot plan, she is over the moon, well chuffed, and
even drives me over to Dan’s to pick up the 316. Top bird.
Now, we have a tradition of naming race cars, my Jag is the Black Pearl
due to it being an old wreck with a mind of its own. Diana’s first
suggestion for her beemer was a surprise; ‘the Black Turnip’.
Once back in the bat cave I start laying into the helpless 316, more bits
go on Ebay, particularly surplus switches, trim and dash parts, further
helping the balance of payments. The usual pile of unwanted carpet and
sound deadening foam builds up on the floor but it was noticeable that
all these parts were quite light weight, particularly when compared to
similar parts taken off my Jaguar XJ-S, obviously BMW put some thought
into this, even the boot lid brackets are full of holes like something
off an aircraft.
Out come the small radiator headlights and all the front trim, I don’t
want to risk damaging it during the engine swap. The bonnet seems to have
a bizarrely complex mechanism in order to open over the front, allowing
it to rise up before going forward. Why didn’t they just put the
hinges at the back and save a lot of bother? Anyway, When I fit the bonnet
pins I can ditch all of that clag and save a little more weight, I will
also trim the bonnet stiffeners, but not too much because the force of
the air at speed can fold a floppy bonnet in half very easily. A similar
treatment will befall the boot lid.
One of the things I do to make life easier is spray white paint round
the usually dark areas of the engine bay, it doesn’t have to be
pretty but it makes a heck of a lot of difference when working on the
Whilst in the transmission tunnel area, I set about ripping out the substantial
sound deadening matting, its not as weighty as some people may have you
believe but ads up to about 2 kg with the heat shields. Although a race
engine will obviously produce more heat, it is at high road speeds so
heat shielding is less critical in some areas. The big problem on a race
cars is heat soaking into sensitive components when you finish and park
up in the pits, even after a cool down lap. Heat shielding may not help
if there is no where for the heat to go, so the best bet is to ensure
good ventilation for hot things and open the bonnet immediately after
It's interesting seeing the differences between the 316 and the slightly
older 325, things like the engine mounts on the 316 are much softer and
have little dampers on to keep things under control, loads of mounting
lugs and bolt holes are in different places.
Now here’s a thing; the gearbox on the six is about 31/2 inches
longer than the one on the 4. Luckily I had the foresight to remove the
propshaft from the donor car, how cunning is that? Well, not very as it
turned out, the centre bearing unit is held on to the transmission tunnel
with two bolts, when I offered the unit up it simply didn’t fit.
Somewhere along the line the trans tunnels on E30s must have changed slightly,
the later one being about 3mm narrower. Time to wake up Mr Anglegrinder,
bearing in mind that the mounting lugs are strengthened by bending the
metal to form a double thickness, so grinding the edge results in it falling
in half. But the bit that falls off can still be used as a big washer
and a small spacer brings the prop down to the right hight.
The radiators are vastly different too, the older 325 item is larger,
not surprisingly, but the 316 item has an integrated header tank on the
side making the unit much wider than the 325 unit, but the 325 one is
much taller and fits on to a bracket that isn’t there on the 316.
Not only that but there now appears to be a different cross member in
the way which also mucks up the oil cooler mounting. So a few more holes
were fitted and some creative bracketry made.
Not being one to be put off easily, I set about slotting the 6 into place.
It’s a very snug fit and required a degree of swearing. The 316
PAS hoses don’t fit so I needed the 325 ones, unfortunately I had
cut them in half when forcibly removing the engine, the word ‘arse’
springs to mind. Luckily it was quite easy to make a new one. Then I found
the earth lead is on the other side of the engine, but other than that
it fits nicely.
The 325 gearbox is further rearwards and requires the 325 mountings to
be bolted to the 316 crossmember, which is exactly the same as the 325
one and is attached to the body via square headed semi-captive bolts that
can slide fore/aft in a slotted channel, presumably so that BMW could
fit the various engines to the same body. So all I need to do is slacken
the nuts and slide the crosmember rearwards, the only difficulty is one
of the captive nuts in the trans tunnel ended up not so captive.
Whilst at that end, I noticed that the gear selector mechanism, although
undoubtedly ingenious, had quite a lot of slack in it which is not so
good for racing gear changes, getting 2nd instead of 4th will ruin the
day. Now, I could have just replaced the worn parts and fitted an extension
on the bottom of the gear stick in order to shorten the throw. But I didn’t.
What I did was make a totally new mechanism with a solid support bar bolted
to the gearbox and a rose jointed gear stick allowing a lot of adjustment,
I have to say it now has a very positive action and I like it.
Further complications come from the fact that the interior heater pipes
are different, requiring a hybrid joined with a short tube, the airbox
mounting has moved, solved with an adaptor plate, there is no coolant
header tank mounting, requiring a fabricated bracket, and also there is
no mounting for the small relay pack. At this point I realise that I have
just put a huge amount of effort into making a normal 325! It really would
have been easier to have paid the extra and bought a good 325 in the first
place. But its looking almost ready to run now so I am feeling positive.
Next I turn my attention to the exhaust, taking the centre box and cutting
the pipes to route them out the side just ahead of the left rear wheel,
just like the old touring cars did. This saves the weight of the back
box and makes getting at the rear axle slightly easier. Also it’s
a very cheap tweak, removing a little back pressure.
The wiring requires surprisingly little work, the engine loom is connected
to the car by a round multi-plug, and although there are some different
wires and colours in, all the main functions are there and I just connect
the plug. The only other connection is some power feeds which are expecting
a positive terminal to be located on the bulkhead, which isn’t there,
so its just a matter of running them through to the battery. The ignition
barrel has to be removed for safety, leaving the ignition switch abandoned.
It has to be said that my favourite dash board s are on aircraft, so this
is a brilliant excuse to fit a toggle switch with a nice shiny red flip
cover for the ignition and a splendid red push button for the starter.
To make it look nice I make a little ally switch plate up that fits where
the radio used to go, to prevent accidental switch operation I make a
pair of switch guards out of thick wire. Nice.
Now, I suppose a radiator would be a good idea, as luck would have it
the old 325 radiator doesn’t fit. The metalwork at the front of
the car has subtly changed and now there is nothing to hold the rad up,
so I cut a strip of ally and make a simple cross member with the lower
rad mounting rubbers bolted in, these being made from the 316 radiators
top mounting bracket cut up a bit.
Whilst in the area its time to create some form of electric fan arrangement,
lying on the pile of bits left over from other projects is a twin fan
assembly from a Jaguar that has only one working fan. A bit of creative
hacking and it fits nicely behind the grill. As we only need it when the
car comes into the pits, I fit a switch to the ignition panel and a relay
in the engine bay, wired so that it can be switched on even with the ignition
Before running the engine again, I do a full service; new cam belt, tensioner,
dizy cap, oil filter etc. In go the BPR6ES plugs, allegedly increasing
power slightly, and crucially the oil is upgraded to Castrol Edge which
performs reliably under race conditions. Also, a little ‘water wetter’
goes into the coolant, This helps break down the surface tension layer
allowing the coolant to contact more of the engine surface. The coolant
is only 20% glycol because water is much better at carrying the heat away
but we still need the corrosion protection and the increased boiling point.
Speaking of which, the battery is moving house, the 325 had it in the
boot whilst the 316 had it in the engine bay. By contrast I am going to
put it behind the passenger seat in an FIA compliant sealed box, the main
lead then going up the trans tunnel to a dash mounted FIA type cut off
switch. The switch is also operated by a pull handle on the front bulkhead
so that marshals can cut power and stop the engine in the event of a ‘racing
incident’ that renders the driver incapable.
The switch not only disconnects the battery but also cuts power to the
ignition, otherwise the engine would carry on running powered by the alternator.
To protect the alternator from the potential open circuit, which could
blow the diodes, a dump resistor is wired in. It’s not as complicated
as it sounds. Honest.
Time for a test run, always exciting starting an engine after its been
buggered around with.
Unfortunately events overtake us, as Diana has to go into hospital early
and paying jobs in the workshop take priority over the little red racer.
So the ‘plan’ adapts, I will get it running without roll cage
etc for a RWYB drag race in two months time, followed by a track day and
then strip out the windows to fit the cage over the winter.
More to follow....
Roll cages are bloody expensive, trawling the second hand ads was getting
no where, and anyway you should never buy second hand safety equipment.
All the FIA approved cages seemed to be above 400 quids. On a trip to
Basingtoke (visiting Caparo, not just a strange form of sight seeing)
I found X-Sport, builders of Production BMW championship cars, and after
a brief chat with the very helpful guys there I not only know a few more
tricks for building a good 325 but I had managed to buy a cage at a very
reasonable price. They don’t usually sell their cages, roll cages
are notoriously difficult to fit and the hassle that novice customers
can give them was just not worth it, but after I took an oath sworn over
a Heynes manual not to winge when I get stuck, they gave in.
Tuning an engine without spending money is always a challenge, luckily
BMW tend to tune their engines for performance as standard, but there
are still a few juicy options. Obviously cutting most of the exhaust system
off should reduce restriction and a free flow air filter should help a
little, but there is a relatively cheap way of increasing capacity. The
525e actually had a 2.8 litre engine, tuned for economy. Swapping the
325 block for the 525e unit puts the sportier 325 heads on a bigger capacity
block, allegedly it bolts straight on, now where have I heard that before....
Spark plugs in a race application have to cope with high heat levels for
longer and so should be changed for ones of a higher heat grade. In this
case we will go for NGK BPR6ES which allegedly give a few more bhp.
One thing that is often missed is oil, this not only dictates the reliability
of the engine in extreme conditions but also has a significant effect
on power losses due to drag, friction and windage as the spinning crank
wacks into blobs of flying oil. Using the right grade is essential, and
one with additives that can cope with extended high temperatures
Race sprigs are surprisingly cheap, they come in 2.25 or 1.9 inch diameters
and there is a very cheap way of making an ordinary front strut into a
racing strut using a threaded tube that slips over the strut body and
accepts adjustable spring platforms, allowing the ride height to be changed
but just as importantly it allows the corner weights to be balanced out;
improving suspension performance.