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Submitted by Tom Hatem and Scott Scharadin

Anyone who has driven an E30 knows it is a special kind of car. The narrow pillars and squared off corners afford great visibility making the driver feel instantly comfortable. Light weight, good handling and road feel are reasons why E30s are still on the road and the track.

Some believe the M3 is the more desirable E30 until they discover virtually everything about the M is unique and therefore more expensive. A non-M E30 offers great balance and feel, a lower entry price, solid reliability and more affordable performance upgrades.

Our project actually started in 1999 when the owner recognized his Porsche 911 was going to be very expensive to maintain for track use. He was referred to Hatem Automotive who helped locate a 1988 325is with 80,000 miles, a worn suspension and a tired, poorly maintained motor. Over the years, the car has been transformed from a multi-purpose street and driver school car to a single purpose racing car. Since its original overhaul in 1999, the car has logged more than 20,000 track miles.
In 2010, at a BMWCCA Club Race last year at Mid-Ohio, the owner recognized despite rigorous maintenance, the strain of competitive track use was exceeding the limits of the 325is. Fourteen inch wheels and tires did not offer enough grip. Frequent brake pad changes could not overcome the fact there was not enough brake. The brake caliper boots were melting and the overheated wheel bearings had been changed one too many times. The problem was he still loved his E30. Hatem Automotive suggested upgrading the E30 using suspension and brakes from an E36. In other words, turn the E30 into an E30-36.

Almost as many performance parts exist for an E30 as an E36. The E36 components, however, offer more options for larger tires and wheels and the brake upgrade is a substantial performance improvement. The E36 rear brakes are larger than the original E30 fronts. Any E36 upgrade benefits from 5-lug wheels, larger tires and bigger brakes. Any experienced do-it-yourselfer with basic welding and fabrication skills can convert an E30 to E36 brakes and suspension. One-off projects are especially challenging to anticipate everything that may go wrong. Working on any 20-30 year old car usually includes finding rust and fragile metal that can compound unexpected problems. Start with a written plan and parts list. Then shop and price suppliers and guesstimate the time to install. Previous experience with BMWs is always an advantage but, with such a large following of E30 enthusiasts, help is available. We found a lot of pictures on the Internet that helped avoid mistakes.

With the change to E36 components, expect an $80 control arm to become a $160 control arm. A $40-$60 E30 wheel bearing becomes a $90-$100 wheel bearing but, even in competition, E36 bearings last twice as long. Since we were upgrading an existing race car, we used E36 M3 and Z3 M underpinnings. If maximum performance isn't required, non-M E36 parts are cheaper and still result in significant improvements. Because of budget, some of the parts we used were from a salvage car.

Any E36 front suspension basically bolts on without modification. The rear conversion, however, is very, very labor intensive. The rear suspension upgrade requires changing the whole drive train, dealing with axle bolts, control arm bolts, removing the differential, lowering or removing the exhaust, lowering or removing the driveshaft, working with park brake cables, rear brakes, brake lines and rear suspension. Assume three hands will be needed to change the front suspension. Four hands are essential when working on the drive shaft, the sub-frame and the differential. Some fabrication skill is required to construct brackets to mount the rear disk brake lines.

Make certain the car is aligned before beginning. The E30's fixed rear sub-frame has a tendency over time to "dog-leg." Access to an alignment rack is a huge plus but, a string alignment using 4 jack stands, heavy string, plumb bob, tape measure and a small increment ruler can be used to set toe and insure the correct thrust angle according to the chassis centerline.

There are multiple types of control arms so, without knowing all the combinations, a strong recommendation is to measure and mark the rear before taking it apart. For a racing application, slot the holes for every expected modification. If there is time and budget, mark or tack weld all the modifications to the rear sub-frame using elongated holes for fine tuning. Put it back together and check the alignment. Take it apart again, make the adjustments. Then weld in rear camber and toe adjusters. Reassemble and complete the final alignment. In our first attempt using a one-step process, we ended up cheating ourselves out of some of the rear camber because we didn't anticipate how much elongation was needed in the slots to adjust.

We used the rear suspension from a Z3 M roadster but a M Coupe or any standard 2001-2002 Z3 will work as will an E36 318Ti. Rear caster is non-adjustable in the E30 and not even measured. All Z3s are based on the same suspension but the M has increased castor factored in. The M cars have larger brakes, and are much beefier with a larger rear wheel bearing, welded in reinforcement and a larger axle. In any rear conversion, the camber toe adjustment has to be welded to the sub-frame. While the sub-frame is out, replace the sub-frame bushings. Many bushing options are available ranging from stock street bushings, to neoprene, to Delrin, to aluminum for extreme track use only.

The change in wheels and tires is most significant. Standard E30s typically use 185/60, 185/70 or 195/65 14" tires. The standard E30 wheel wells can fit a 16" and some 17" wheel/tire combinations. If using E36 M3 front brakes, 17" wheels or a 16" wheel designed for brake clearance will probably be needed. Depending on wheel and tire choice, the fenders may need to be rolled slightly. Because we lowered the car for racing, we turned to Autobody Specialists in Columbus to modify the fenders. Brian Hoover cut out the old wheel openings and fabricated new steel flares which look like they came from the factory. Brian did have to use a large persuader on the inside wheel wells to clear the 17x8.5 wheel and 245x40x17 tires. The car looks awesome with the new wheels and fenders. Handling and braking are dramatically improved and the first runs showed the braking zone was reduced by 200 feet on Mid-Ohio's back straight!

In spite of these improvements, most anyone who has started these types of projects usually finds there is always more to do. After 20,000 track miles, the 2.5 liter "i" motor didn't have enough steam left to pull the big rear wing or turn the 17" wheels. To take advantage of all the new improvements, more horsepower and certainly more torque were obviously needed.

We found an '88 528 2.7 liter eta block and commissioned Chuck Baader of Birmingham, Alabama to do his magic. Chuck rebuilt the motor using custom pistons and a Paul Poore baffled pan. The head has a Schrick cam and Stahl headers. Engine management uses a megasquirt system. Not much gain in rear wheel horsepower but torque is up by about 25 ft/lbs. We reduced rear wing size and the car pulls strong. The latest modifications, however, have altered the classification for BMWCCA racing. We are waiting on the final ruling which could mean we will be back in the shop looking for more weight savings.

Editor's note: Tom Hat em owns and operates Hatem Automotive in Columbus, Ohio