The Build – August 2025

/ Build / By

1st – 24th August 2025

A bit of a bulk update as things have been busy and little time to keep the blog current.
Here’s a list of work done in the last three weeks or so:

  • Alternator installed and then removed / modified to increase clearance with the steering column.
  • Engine mounts upgraded to firmer / taller items to help the alternator and clutch slave cylinder clearance issues.
  • ECU panel painted and rivetted / bonded to chassis.
  • Flexi fuel line installed under intake manifold using OEM ‘hanger’ ready to connect to fuel rail.
  • Engine loom modified to delete the three connectors at front o/s of the engine, the EGR connector, MAF connector (MAP sensor will be fitted) and other connector wiring shortened.
  • Main, front and rear looms stripped of no longer required wiring, connectors and relays.

I decided to do away with the stock rubber engine mounts and go with a set of these, which were very well made with removable studs to ease fitting:

Revshift polyurethane MX5 engine mounts.

Reason being that the original items seem to squash a little too much and along with the aftermarket alternator, I needed to resolve the rather poor clearance between the latter and the steering column (despite already grinding a little off of both the alternator casing and the oil pump pressure relief access boss).

These items are stiffer and slightly taller (~8mm). They are tad pricey once you factor in UPS shipping from Michigan, but everywhere in the UK seemed to be out of stock of similar.

Whilst fitting them I took the opportunity to nudge the engine over a little more to the nearside by putting a 2mm washer between the offside engine mount and the block, at each fixing point, and elongating the MK bracket holes where the new poly mounts bolt to.

Otherwise most of the rest of the time has been taken up with loom reduction / modifications. Having as much information as you can is highly advantageous in this task, much time spent pondering the wiring diagrams to check ‘dependencies’ before removing wiring. As I’m installing an ME221 ECU, there’s a fair bit more ‘rationalistion’ that can be done to the looms – we’ll see if that was a good idea quite soon!

Here are the pics:

Image of engine just before installation with alternator fitted.
Engine just before installation with alternator fitted.
Image of car with engine installed, outside with engine loom mods in progress.
Engine installed, outside with engine loom mods in progress.
Image of car with engine installed, outside with engine loom mods in progress.
Engine installed, outside with engine loom mods in progress.
Image of car with engine installed, outside with engine loom mods in progress.
Engine installed, outside with engine loom mods in progress.
Image of car with engine installed, outside with engine loom mods in progress.
Engine installed, outside with engine loom mods in progress.
Image of newly installed polyurethane engine mount.
Newly installed polyurethane engine mount.
Image of slightly elongated engine mount hole to shift engine over a little more to the nearside.
Slightly elongated engine mount hole to shift engine over a little more to the nearside.
Image of newly installed polyurethane engine mount ready for upper stud and nut.
Newly installed polyurethane engine mount ready for upper stud and nut.
Image of steering column clearance after new engine mounts installed and various bits of alternator housing and a small area of oil pump had been ground down.
Steering column clearance after new engine mounts installed and various bits of alternator housing and a small area of oil pump had been ground down.
Image of clutch slave cylinder clearance after new engine mounts installed.
Clutch slave cylinder clearance after new engine mounts installed.
Image of engine loom modifications in progress.
Engine loom modifications in progress.
Image of main loom ready for modification.
Main loom ready for modification.
Image of some of the wires and modules removed from the loom so far.
Some of the wires and modules removed from the loom so far.
Image of two 'mystery' units in the loom. The black unit is the fog light functionality controller, and the grey the door locking timer.
The black unit is the fog light functionality controller, and the grey unit the door locking timer.
Image of main loom with most of the unnecessary wiring removed.
Main loom with most of the unnecessary wiring removed.
Image of a bin full of removed loom tape and split conduit.
A bin full of removed loom tape and split conduit.
Image of coolant mixer manifold and heater delete bung solution.
Coolant mixer manifold and heater delete bung solution.
Image of coolant mixer manifold and heater delete bung solution.
Coolant mixer manifold and heater delete bung solution.
Image of engine just before installation with alternator fitted.
Engine just before installation with alternator fitted.
Image of car with engine installed, outside with engine loom mods in progress.
Engine installed, outside with engine loom mods in progress.
Image of car with engine installed, outside with engine loom mods in progress.
Engine installed, outside with engine loom mods in progress.
Image of car with engine installed, outside with engine loom mods in progress.
Engine installed, outside with engine loom mods in progress.
Image of car with engine installed, outside with engine loom mods in progress.
Engine installed, outside with engine loom mods in progress.
Image of newly installed polyurethane engine mount.
Newly installed polyurethane engine mount.
Image of slightly elongated engine mount hole to shift engine over a little more to the nearside.
Slightly elongated engine mount hole to shift engine over a little more to the nearside.
Image of newly installed polyurethane engine mount ready for upper stud and nut.
Newly installed polyurethane engine mount ready for upper stud and nut.
Image of steering column clearance after new engine mounts installed and various bits of alternator housing and a small area of oil pump had been ground down.
Steering column clearance after new engine mounts installed and various bits of alternator housing and a small area of oil pump had been ground down.
Image of clutch slave cylinder clearance after new engine mounts installed.
Clutch slave cylinder clearance after new engine mounts installed.
Image of engine loom modifications in progress.
Engine loom modifications in progress.
Image of main loom ready for modification.
Main loom ready for modification.
Image of some of the wires and modules removed from the loom so far.
Some of the wires and modules removed from the loom so far.
Image of two 'mystery' units in the loom. The black unit is the fog light functionality controller, and the grey the door locking timer.
The black unit is the fog light functionality controller, and the grey unit the door locking timer.
Image of main loom with most of the unnecessary wiring removed.
Main loom with most of the unnecessary wiring removed.
Image of a bin full of removed loom tape and split conduit.
A bin full of removed loom tape and split conduit.
Image of coolant mixer manifold and heater delete bung solution.
Coolant mixer manifold and heater delete bung solution.
Image of coolant mixer manifold and heater delete bung solution.
Coolant mixer manifold and heater delete bung solution.
Image of engine just before installation with alternator fitted.
Image of car with engine installed, outside with engine loom mods in progress.
Image of car with engine installed, outside with engine loom mods in progress.
Image of car with engine installed, outside with engine loom mods in progress.
Image of car with engine installed, outside with engine loom mods in progress.
Image of newly installed polyurethane engine mount.
Image of slightly elongated engine mount hole to shift engine over a little more to the nearside.
Image of newly installed polyurethane engine mount ready for upper stud and nut.
Image of steering column clearance after new engine mounts installed and various bits of alternator housing and a small area of oil pump had been ground down.
Image of clutch slave cylinder clearance after new engine mounts installed.
Image of engine loom modifications in progress.
Image of main loom ready for modification.
Image of some of the wires and modules removed from the loom so far.
Image of two 'mystery' units in the loom. The black unit is the fog light functionality controller, and the grey the door locking timer.
Image of main loom with most of the unnecessary wiring removed.
Image of a bin full of removed loom tape and split conduit.
Image of coolant mixer manifold and heater delete bung solution.
Image of coolant mixer manifold and heater delete bung solution.

The plan now is to get to first start in the next two weeks. Here’s the list that needs to be done:

  • Additional rivets in ECU panel.
  • Connect flexi fuel line to fuel rail input
  • P clip rigid fuel lines to chassis near to front as poss.
  • Connect rigid fuel lines to flexi fuel lines.
  • Bracket for fuel regulator – extra long for engine loom P clip?
  • Fit rubber bungs to unused coolant outlets.
  • Fit ME221 into ECU box.
  • Mount ECU
  • Run in engine loom & wrap.
  • Trim gearbox mount bolt.
  • Order intake manifold gaskets and oil filter
  • New exhaust manifold studs and nuts?
  • Fit Lambda sensor.
  • Fit exhaust pipe.
  • Temp fit main fuse box and cables to alternator / starter / battery
  • Temp fit main loom & connections to ignition / dash
  • Tighten spark plugs
  • Torque crank pulley bolt
  • Fit oil filter
  • Fit dip-stick
  • Engine oil
  • Gearbox oil (90ml in to turret and fit gearstick)
  • Diff oil
  • Might it start? (Program base map into ECU)

Related Posts