Dean's Tweety Bird

db z3 fullbody_1

This car started out the same way many projects do, with a simple problem. Dean noticed that his car had worn thrust bearings and a large amount of movement in the crank and came to us for the fix. 

Once we got ahold of the engine, we dismantled it and found that the crank was trashed, and it took plenty of other parts with it. The problem was easily solved, though. We knew the engine needed to be supercharged from the get go because he already had a Rotrex based kit installed, so we helped him pick out a crank that fit the application. He decided on our new 3.5l 97mm stroke S50 crank (OBD1) as a replacement. We also added an ATI OBD1 High Performance Crank Damper to avoid the bearing issues in the new build. In our experience, the Rotrex based kits don't make a lot of top end PSI, so Dean decided to upgrade to a custom RMS blower kit with a V3si trim blower to make some bigger numbers. 

We replaced the pistons with a JE set, uprgraded to our custom SP rods, and added VAC Coated Rod and Main Bearings. It's held together by a full ARP hardware kit. We also added our Oil Pump Upgrade Kit and an Oil Pan Baffle to insure the longevity of the build. 

db z3 engine

The head is our mild stage 2 head, and is outfitted with a stage one supercharger cam set made by Schrick. We reused the metal Schrick manifold that was already on the car to top off the engine for boost.

db z3 schrick

The exhaust starts off with an Active Autowerkes supercharger header, which collects into a single stainless 3” custom exhaust that splits in to two oval tailpipes.

db z3 rear

Spark is handled by a set of Okada coils.

To really increase the performance, we also upgraded his clutch to a Clutch Masters FX300. It's a sintered kevlar clutch that feels like stock, but handles roughly 110% more torque than stock. 

The rear end was beefed up with an OS Giken LSD and geared up to a 3.15 ring and pinion (stock was a 3.46). Dean already had a dual ear E36 Rouge Finned Differential Cover and a full Strong strut Subframe Reinforcement Kit installed on the car. While we dismantled and reinstalled the rear we also installed our Toe and Camber Kit to the rear end. The suspension was topped off with TC Klein’s Double Adjustable Coilover Kit with custom spring rates.

We didn't need to do any work near the wheels because he already had an upgraded StopTech Front Big Brake Kit and braided brake lines.

db z3 brakes

When we tuned it on our all-wheel drive Mustang dyno, the car saw just over 400HP to the rear wheels with a massive amount of torque. This car is a complete and well-designed example of a perfect back road missile. You'd hardly expect it, but it drives with the ease of a stock car. It's a great example of what VAC can do besides building some of the fastest race cars out there.

Dean is planning on coming back and adding a Samsonas sequential and standalone ECU upgrade to take the car to the next level. We may actually go to a stage 3 head and stage 2 Schrick supercharger cams in the next revision of this little Z3.