CR14DE Engine Installation Complete

Mini 1275GT Resto-Mod, Apr-2018

I’ve had the car out for a couple of shakedown runs. The most immediate impression is the huge power & torque increase over the ‘A’ series, even with a guesstimated tune and without the Variable Valve Timing (VVT) connected. First gear is almost redundant as there’s so much torque it easily pulls away in 2nd. The car leaps forward with a touch of throttle in 2nd, 3rd and even 4th.

Here’s the completed engine bay, need to tidy up the wiring etc but can do that as a running project…

The main features of this installation:

  • Own-design ECU modified to suit the Golf TB and also to provide a control output for the VVT solenoid.
  • Standard Mini radiator mounted on the front, but may swap for a ally version depending on how this performs.
  • Electric fan controlled by the ECU
  • Dual circuit but non-servo brakes. Brake pedal effort still a bit higher than I’d like so will experiment with different pads.
  • Fuel pressure regulator, set at 2 bar for now.

The drive shafts obviously need to be Mini at the outer end to suit the Mini hub and Nissan at the inner end to fit the transmission sliding joint. So, in the time-honoured fashion, the Mini and Nissan shafts were cut to the required length and the required Nissan/Mini part-shafts were joined together to provide the hybrid drive shaft. The part shaft ends at the join were turned down to the same diameter and inserted into a tight-fitting sleeve of 60mm length and 4mm wall thickness. The sleeve was TIG welded to each part-shaft and plug welded through pre-drilled holes. No runout was measurable on completion. Completed shafts just back from the engineering shop:

Painted, assembled and ready to fit:

The shaft lengths were defined by the smallest distance from the hub CV to the transmission CV which occurred at the bottom of the suspension travel (i.e. the rebound position). The length of each shaft is: RHS: 545mm, LHS: 322mm.

I fabricated an intake manifold from mild steel tube with an end plate for a Golf Mk3 Throttle Body. The manifold is simplified for the CR14DE engine, as the injector ports are machined into the cylinder head. The flange was laser cut from a template I drew up using Turbo CAD. This design will probably limit performance due to the sharp 90 degree bends, so I have plans for a “proper” aluminium intake manifold with a larger plenum and better flow properties.

I chose the Golf Throttle Body (TB) as it has an idle control motor that can be controlled using a Pulse Width Modulated (PWM) signal. PWM allows a simpler installation compared to a stepper motor as found on other TB’s.

I’ve used the Nissan’s original exhaust manifold by cutting off the integrated catalytic converter and welding on a 2 inch diameter pipe section in its place. The rest of the exhaust was fairly straight forward, as shown below:

The exhaust is supported under the engine by a bracket on the engine steady mount and connected to the remainder of the exhaust by a stainless steel flexible coupling: