Dinan S3-M5 : A Closer Look at this Beast of a BMW

Mark at Pelican Parts · Mark at Pelican Parts's Garage

Recently, we caught-up with our friend Mel, who is the proud owner of a vicious-looking Dinan M5, as he put the beast through its paces on a twisty southern California canyon road. Back in the day, the M5 was a stout performer right off the showroom floor in stock form and still holds its own against more modern day machinery quite well. But then came Steve Dinan who performed his magic to a select number of E39 M5s in the form of stages, from the S-M5, S1-M5, S2-M5 & finally the S3-M5 with the last version receiving the coveted S3-M5 Supercharger System among numerous other high-quality Dinan performance pieces. Let's hear from Mel himself and his experience with the Dinan S3-M5.

I had been looking on and off for an E39 M5 when I came across this beast for sale late last year. Truly had been a "spare no expense" car (I have over $100k in receipts on top of the cost of the car!) The first owner had done an S2 conversion, then when the S3 package came out sent it back to Dinan to get it redone. I believe only about 30 of these S3s were ever created by Dinan (don't quote me on that), which makes these pretty rare out there.

The S3 conversion included (among other things):

-S3-M5 Supercharger System;
-S3 Engine Management Software and Electronics;
-High Flow-Ram Air Intake;
-High Flow Throttle Bodies and Tuned Velocity Stacks;
-4:2:1 Stainless Steel Headers;
-Free Flow Exhaust;
-Strut and Shock Tower Braces;
-Stage 3 Suspension System-JRZ
-Rear Subframe Reinforcement;
-Dinan/Brembo Brake Conversion;
-Dinan Lightweight Forged Wheels: Front 18 x 9'' (275/35-18 Tires Sold Separately; Rear: 18 x 9.5''
(285/35-18 Tires Sold Separately);
-S3-M5 Clutch Package (including Flywheel, Disc/Pressure Plate and Slave Cylinder);
-3.45 Limited Slip Differential

Driving this beast is downright scary. I haven't personally dyno'd it (Dinan rated it at 600+ HP and 500+ ft/lb of torque)- but I also own a Porsche 993 Turbo with a few mods and the Dinan S3 feels like it could potentially out-accelerate it. Not only is it quick, it just keeps pulling and pulling (top speed on this is supposedly 190+).

As Dark Helmet would say "...we're gonna have to go right to ludicrous speed" Turning off traction control would mean budgeting a new set of tires every few months. Unreal handling too - amazingly compliant on the crappy LA roads yet turns in crisply and with minimal body roll. A lot of fun in the canyons despite its size.

IMO, the exhaust note is right up there with an Aston (flamesuit on

) I haven't come remotely close to exploring its limits as it would be completely irresponsible on public streets. Really belongs on the track - where I hope to take it once I get enough skills to not kill myself in this monster.