Anglia 105E Kent Engine to MX5 NC Gearbox fitting guide

Prepping the gearbox

  1. Notch the gearbox to clear the starter. Offer the adaptor plate to the gearbox and loosely hold in place with a couple of the fixing bolts. The dowels on the adaptor plate will line everything up.
  2. Offer the starter motor to the plate and note where the nose of the starter clashes with the box.
  3. Grind out the box until the starter motor bolts up flush onto the adaptor plate.
  4. Cut back the top mounting hole on the gearbox to allow for clearance to the bulkhead/tunnel. You can see in the picture below the gearbox hitting. Grind this back by approx 10mm keeping it flat. If you don't do this you may not get the correct angle on the drive train.
  5. Trim off any excess webbing from around the gearbox to allow plenty of room in the tunnel.

Prepping the car

  1. Cut the tunnel out as shown below:
  2. If your car isnt a super model with removable crossmember under the cart, offer up the gearbox mount/crossmember ensuring it is central.
  3. Clamp in place and drill through the mount 11 diameter for the 4 off M10 bolts to hold the mount in place.
  5. Mark out and cut out the centre section of the chassis.

 

Fitting the gearbox mount/crossmember to the gearbox

  1. Remove any fixings on the rear of the gearbox and bolt on the steel wedge part of the mount with the supplied M8 fastenings, there are 3 in total.
  2. Ensure all other fastenings on the mount are loose so its easier to line everything up further down the line.

 

Cutting the hole for the cable clutch fork (If using one)

  1. Mark out the cut for the hole in the side of the gearbox as per the dimensions below in the picture.
  2. Remove the existing release bearing by pulling it away from the fork. This is to ensure no swarf gets in the bearing.
  3. Cut the corners out using a hole saw. I use a 35mm saw but this can be slightly smaller or you can just cut it all square with a grinder.
  4. Cut out the rest of the hole with a grinder and then remove all burrs and clean out the bellhousing to remove any swarf.

Using the original hydraulic slave cylinder

  1. Remove the existing release bearing by pulling it away from the fork, discard the bearing. 
  2. Pull the fork out of the box.
  3. Remove the 12mm headed bolts from the input shaft cover.
  4. Remove the input shaft cover. 
  5. Cut the input shaft cover down by 10mm.
  7. Measure the height of the pivot point from the back face of the cover. It is usually 63mm. Unscrew the pivot and cut 5mm from the cover. Screw the pivot back in and remeasure the height. The height must be 58mm when using one of our clutches. This may need altering if running a different clutch on a twin cam. 

  8. Refit the input shaft cover, thoroughly cleaning it, ensuring you have removed the existing sealer and apply flange sealant to the face. 
  9. Refit the fork through the side of the box using an RX8 bearing. 


Fitting the cable clutch pivot (If being used)

  1. Remove the existing release bearing by pulling it away from the fork.
  2. Pull the fork out of the box
  3. Unscrew the original pivot point from the box.
  4. Remove the slave cylinder on the side of the box by undoing the 2 bolts..
  5. Remove the 12mm headed bolts from the input shaft cover.
  6. Remove the input shaft cover. 
  7. Cut the input shaft cover down by 10mm.
  8. Cut the original pivot point back flush with the webbing on the cover to clear the new clutch fork.
  9. Refit the input shaft cover ensuring you have thoroughly cleaned it and removed the existing sealer and apply flange sealant to the face. 
  10. Offer up and bolt on the new pivot point and tighten all fastenings. 
  12. Pass the new clutch fork through the hole made in the side of the box and then put the slotted end onto the pivot. Ensure that the webbing on the fork is facing you.
  13. Fit the RX8 original release bearing to the new cable clutch fork and then twisting to hold in position.

Fitting the hydraulic concentric release kit

  1. Remove the existing release bearing by pulling it away from the fork.
  2. Pull the fork out of the box
  3. Unscrew the original pivot point from the input shaft cover.
  4. Remove the input shaft cover from the box
  5. Cut off the input shaft cover guide for the original release bearing taking it flush with the ribs on the cover. 
  6. Refit the input shaft cover ensuring to clean everything and use a flange sealant like loctite 510 to reseal. 
  7. Remove the slave cylinder on the side of the box. 
  9. Bolt on the concentric release bracket using the 4 M8 cap head bolts provided.
  10. Pre fill the slave cylinder by submerging the pipe that would be connected to the master cylinder in brake fluid.
  11. Slowly squeeze the slave cylinder together and slowly release. repeat this slowly until no bubbles come from the end of the pipe.
  12. Bolt on the concentric release cylinder using the 3 M6 cap head screws.
  13. Make sure that the concentric release cylinder is sitting flush against the bracket and that there is clearance in the back of it between the input shaft cover/sleeve. 

Fitting the adaptor plate to the engine

  1. Remove all existing locating dowels on your engine.
  2. Offer the adaptor plate up to the engine and fit the top two countersunk bolts loosely
  3. Nip up one of the countersunk bolts to centralise in the hole.
  4. Fully tighten the second countersunk bolt and then go back and fully tighten the first one
  5. Fit the M10 x bolts with flat washers from the engine side into the adaptor plate and fully tighten.


Bolting the engine to the box (Countersunk bolts are 3/8 not M10)

  1. Lift the box up to the adaptor plate and slide it over the locating dowels.
  2. Fit the M10 bolts that hold the box to the engine as shown below.

To help in fitting the gearbox to the engine when it is in the car, tilt the front of the engine upwards and hold it in place while you bolt the gearbox to the adaptor plate.