​Well, it's done. What started as a simple upgrade to more modern window motors, then degenerated into a new, modern loom, interior refresh, and repair of various things that either didn't work, or were repaired poorly by previous owners, has finally reached the finishing stage.  Eight long months after putting the car on the lift, it set tires on the ground and went for a short drive Thursday, before the rain set in that night. No issues. Nothing fell off, no Lucas smoke was released into the atmosphere, no concerning odors or sounds led me to pull over, and everything except the headlight pods appears to work. As part of the project, I rebuilt the headlight pod vacuum switch, but there was a real chance there was a leak elsewhere in the system. However, the engine would need to run to verify. Well, now that it's run, I can verify there is a leak, but that's a repair for next week. 

Provided I didn't screw up any crimps or solder joints destined for future failure, I'm pleased with the outcome. The 3D printed fuse/relay box turned out great as did the 3D printed glovebox behind which it sits. Even the interior flocking looks OEM. The carpet looks good, and upgrading the sound deadening to modern materials appears to have made a noticeable difference. Granted I am relying on memory given the time span between pre-project and post project drives, but road noise seems to have been subdued, providing a slightly more refined experience and creating a more prominent exhaust note. Despite adding the sound deadening (DEI Under Carpet Lite and strategically placed Dynamat Superlight) to places where the old sound deadening was missing, the weight increase was only one pound. The replacement heater valances are crack free, and the new center console is much higher quality that the outgoing piece. Rather than use the old — but period correct — vinyl center console pad with welded cross seams, I opted to use some leather left over from the Caterham build and sewed my own. Personally, I think the stitched accent lines look much better than the factory welded seams. The horn no longer has a mind of its own, and it's loud! 

Scroll through the annotated gallery for before and after photos as well as some of the custom work.

​After a recent blat with a friend who owns a 2019 420R SV, we traded cars to see how they compare. He was curious about the engine and I was curious if the CORE dampers and revised spring rates were worth the money.

Starting with the engines, first, NVH is noticeably greater with the 2.4L. No surprise — it's why Ford fitted balance shafts to the 2.3L version — but it's worth mentioning. Although I don't find the 2.4L at all objectionable in this regard, the 2.0L is definitely smoother. However, it also has less sonic attitude. Compared to the built 2.0L in my old Westfield, I've said that the 2.4L sounds angry. Interestingly, my friend used this same word to described it. I suspect part of that attitude is from the deeper note that comes with the bigger capacity, and the rest comes from the far more aggressive cams. The 2.4L has more torque down low and is far more eager to rev than the stock 420R engine; once the engine gets close to 5000 rpm, it just surges forward at an amazing rate and encourages you to keep going to the 8000 rpm redline. There is no doubt that the 50hp difference is real. Another revelation was just how much lighter the 420R flywheel is than the Raceline lightweight flywheel fitted to the 2.4L and that I also used in the Westfield.  Big difference! Part of me wishes I knew this when building the engines. Doing a little research, it appears the 420R flywheel "might" be a little under 7 lb whereas the Raceline flywheel is a verified 10.39 lb. Call it a 3.5 lb difference, or 35% lighter. The Raceline flywheel aids drivability, but the teenager in me loves how quickly the 420R flywheel revs when blipping the throttle at rest.

Next up is the interior. My car has lowered floors, versus standard floors in the 420R. I had briefly driven this car before placing my order a few years ago. The high seating position compared to the Westfield bothered me and prompted me to order my car with the 2" drop. This drive reinforced that feeling of sitting on the car rather than in it. Everything, however, comes with a downside. In this case, the tall center console interferes with my elbow when selecting third gear. After a while I've adjusted to it, but it was an annoyance to my friend. We both agreed the carbon fiber seats are more comfortable than the standard composite seats. 

​As mentioned above, the aspect I really wanted to compare were suspensions. I decided to invest the money in the CORE dampers while waiting for the kit to arrive. We have a lot of bumpy two-lanes road here and given the power level, I wanted to ensure traction wasn't an issue when completing a high-speed pass on a two-lane road. Simon at Meteor Motorsports recommended the CORE single adjustable dampers combined with spring rates he feels are better suited to the chassis. As delivered from Caterham, the 420R SV has 170 lb front springs and progressive springs in the rear that are claimed to go from 140-250 lb: however, they have been independently tested on a spring dyno, which showed they are not linearly progressive, and instead, have three distinct steps: 83/125/175. In contrast, my setup is 275 lb front, and linearly progressive springs in the rear, ranging from 100-175 lb.
​As soon as we hit a bumpy section of road that includes two big dips I know well, it was immediately apparent the ride in my car was significantly better. That difference continued to the handling. The wheels simply felt more controlled and traction was significantly better. When taking one 90 degree turn in the 420R and only adding moderate throttle, I was surprised to find the rear end coming around. I can add much more throttle in my car on that turn — even with the big torque advantage-- without the rear tires spinning. My friend noticed the same differences, which led us to check tire pressures and ensure they weren't wildly different. Nope, within 0.5 psi. Between the ride, traction improvements, and wheel control, he is now considering investing in a set. Highly recommended!