Engine: 3.0L S50 Inline 6 conversion from a ’95 E36 M3
Transmission: ZF310 5 speed transmission from a ’95 E36 M3
Shifter: Ralco short throw shift kit
Flywheel/Clutch: F1 Racing Stage 1 lightweight flywheel & clutch kit
Differential: 2.93:1 Limited Slip from an ’88 E30 325es
Bushings: Replaced all bushings with Ireland Engineering polyurethane units
Suspension: Ground Control Coil-over conversion: 650# front / 800# rear
Sway Bars: Ireland Engineering 22mm front/ 19mm rear swaybars
Steering: ’95 E36 M3 Quick ratio steering rack
Engine Modifications: Castro Motorsport 2 piece fiberglass air intake box, Custom dual 2.25″ mandrel bent high-flow performance exhaust system built by Castro Motorsport, Custom performance dyno tune
Brakes: Factory E30 M3 spec, with new Brembo blank rotors, Pagid performance brake pads, Ireland Engineering stainless steel brake lines and Ate Super Blue racing brake fluid
Wheels: Staggered offset 17×8.5 BBS CH
Tires: 235/40/17 Federal 595
The story behind the build
One day Chris Castro received a call from our customer Alex, who inquired about swapping an S50 or S52 (E36 M3 motor) into his ’90 M3, which had been sitting in storage for 7 years. As usual we were up for the task! We had successfully completed over a dozen 24 valve Inline 6 cylinder swaps into the E30 chassis prior to taking on this project. Chris Castro spoke with Alex a few more times to iron out all the details of the project and his budget for the car. Next, we scheduled a date to head up to Santa Barbara, meet with Alex in person, and tow his car back to the shop.
Alex had purchased this car out of high school and enjoyed it for almost 3 years before experiencing an overheating incident, which put his beloved M3 out of commission. Knowing full well that the E30 M3 was getting harder to find due to its rarity, Alex made the wise decision to store the car at a relatives’ home until he could put it back on the road. After looking at the cost of an s14 (M3’s original 4 cylinder motor) rebuild, Alex decided to go a different route. He wanted more power then what the M3’s original had to offer, along with a more reliable motor, which offered low cost maintenance. Well he definitely made the right choice, since the US spec S50 and S52 motors are pretty bullet proof and offer a nice power-band for the lighter E30 chassis.
When Chris and I met up with Alex, and pulled the car out of his aunt’s garage, we saw yet another M3 in need of a rescue! The original s14 was missing some parts after Alex’s brother had taken it apart in an attempt to fix it. The motor had seized and was in need of a full rebuild. All the bushings and brake lines were dry rotted and in dire need of replacement. The paint was also a bit dull and needed a good polish to give it some life. Needless to say, this car was the perfect candidate for the project Alex had in mind!
So the car made it’s way down to our shop in North Hollywood, for an Extreme Makeover – Castro style!
After approximately 2 months the car was delivered back to Alex and he’s fallen back in love with his car ever since! We’re very happy with the way Alex’s car turned out, and we’re glad that we were able to help another enthusiast turn their dream project into a reality!
