520R SV build has commenced

[JohnCh]

I've been sidetracked.  Consequently, no progress this weekend, but I do have a couple of updates. 

 

The nice thing about the Westfield's fiberglass body is the bonnet is sturdier than the Caterham's aluminum version and the color is in the gel coat.  Therefore, no paint to scratch or fear that the bonnet will deform simply by looking at it wrong.  Consequently, removing the bonnet was less fraught with concern and I never worried about simply placing it on the ground when performing maintenance.  Not true with the Caterham.  Taking a page from this thread, I made a set of foldable arms to store the bonnet when needed.  I still want to add a little foam or bubble wrap to the faces to increase contact area and further protect the bonnet's underside, but otherwise it's done.

 

 

 

 

Although I forgot to weigh the front CORE/Hyperco assemblies before installing them, I did weight the rears to compare those to the weight of the factory Bilstein/Eibach coilover; a combined savings of 5lb 4.8 oz.  Given the fronts are smaller and the Hyperco springs are a larger diameter than the Eibachs, there is less weight to save on that end of the car.  Assuming the savings is about half that of the rear, it's still close to an 8 lb system saving.  Plus, the COREs mount upside down, further lowering unsprung weight (see photos in previous post).  

 

To make my life a little easier now and in the future, I'm making the scuttle removable.  I started a separate thread about the best way to do that here.  If you've been there/done that with this mod and have guidance on the best way to tackle removing the old rivets given they are painted over, please reply there.

 

Thanks,

John

[JohnCh]

Thanks to the help of a few people on the forum, I was finally able to remove the scuttle.  See thread I linked to above for details if you tackle this yourself in the future.  

 

Since I was doing this solo and wasn't sure if the windscreen would attempt to tip backward once the 4 securing bolts were removed, I burned through a bunch of blue tape and had a razor blade handy to cut them when I attempted to lift it off.  Worked flawlessly.  Probably the only time I'll say that throughout the entire build. 

 

 

For some reason, the factory didn't trim the windscreen rubber on either side.  I can take care of this now that the windscreen and stanchions are removed.

 

 

Wow, that's a lot of wires to undo!  I'm still waiting for my 620 dash wiring sub loom to arrive which will replace a chunk of them, and the AiM will receive signals from the ECU for all the gauges, so most of those wires will also go.  CAN will make this much cleaner.  

 

 

 

With the scuttle removed, I'm left shaking my head at the fuse box.  It seems that a contortionist will be required to reach several of those fuses.  Once I understand how the cover is supposed to fit, I'll see if there is a way to reposition that for much easier access.  The Westfield mounts them under the bonnet in front of the scuttle, which makes for much easier roadside fuse replacement.

 

 

-John

[MV8]

I don't know how much electrical work you want to do. I see the fitment issues as a result of the fuse/relay block length. However, those are four, separate fuse blocks that slide together to form a single. You could slide them apart for two, shorter blocks. They also don't need to be rigidly mounted. I'd avoid a hinged/swinging block assy as the wiring needs to lay a certain way to prevent damage from repeated swinging (bundled together to run the length of the hinge with rub protection and secured at the ends so the twist is spread over as much length of wire as practical).

For the panel to face the seat by rotating the mounting face 90 deg, a strip of .050" or thicker 3003 half-hard could be formed into an L shape over two 2x4s C-clamped together and "slapped" (across the grain) with a third 2x4 about a foot long or you could use a 2x2x1/8 aluminum extrusion (home depot) across the footwell and bolted to the firewall.

A window in the firewall (drilled corners, offset tin snips, and flat file/debur tool) would work well with a strip of angle to rotate the block, riv nuts, and an cover overlapping about 3/4 inch on each side but I don't think you will be able to get to it once everything else is added under the bonnet.

[11Budlite]

11 hours ago, JohnCh said:

With the scuttle removed, I'm left shaking my head at the fuse box.  It seems that a contortionist will be required to reach several of those fuses.  Once I understand how the cover is supposed to fit, I'll see if there is a way to reposition that for much easier access.  The Westfield mounts them under the bonnet in front of the scuttle, which makes for much easier roadside fuse replacement.

 

 

 

-John

John - When I got my Caterham the fuse block was just hanging loosely behind the dash and I couldn't find the cover. I talked to Josh at RMC and he said they usually just cable tied the fuse box to the harness behind the dash, and I contacted Caterham and they sent a new fuse box cover. I ended up cutting a window in the fuse box cover and making up a couple angle brackets with nut plates to mount the fuse box to the fuse box cover with two screws so I have easier access to the fuses. I don't have a photo at work but I can post it later when I get home. I was a little disappointed in some of the wiring (temp and fuel gauges were miswired and I could have overheated the engine without even knowing) but removing the immobilizer certainly helped clean it up.  

[JohnCh]

 

3 hours ago, MV8 said:

A window in the firewall (drilled corners, offset tin snips, and flat file/debur tool) would work well with a strip of angle to rotate the block, riv nuts, and an cover overlapping about 3/4 inch on each side but I don't think you will be able to get to it once everything else is added under the bonnet.

Last night I had this same thought.  I don't think room will be an issue given I won't have a heater box, I'll run a smaller Lithium battery, and I may not use the factory air filter setup.  I'll check space availability once I figure out where things will fit with the revised dash layout and where I mount the ECU.

 

51 minutes ago, 11Budlite said:

I don't have a photo at work but I can post it later when I get home.

 

Thanks Bruce.  Absolutely no rush since I won't get to this for a while, but when you have time, I'd love to see it.

 

-John

[11Budlite]

Two pieces of 90 deg aluminum with nut plates installed and two screws to hold it to the fuse box cover. I didn't have nutserts at the time or I would have used them instead. Makes it a lot easier to check or replace fuses.

[11Budlite]

I'm running an AntiGravity ATX-12-HD-RS and so far it's worked out great. Plenty of cranking power for my Sigma and it weighs almost nothing, I think it's 3 lbs. I have two strips of velcro holding it in place as well as a bar across the top. It does require a special charger as you probably know. 

[JohnCh]

Thanks @11Budlite that's a much better installation for access.  Interesting that the fuse boxes are so different between our cars.  I would expect the fuse count to be the same despite the three years and different engine spec but you have 26 fuses vs. 18 in mine.  Some of that might be attributed to spares, but not all. 

 

I've been running a Ballistic EVO 2 in the Westfield for years.  It's started the car after sitting overnight in mid 30F weather and can be picked up with a thumb and forefinger.  What's not to like about that?  Now that Ballistic is out of business, I'm debating between the AntiGravity and EarthX.  Good to hear yours is working well.

 

-John

[11Budlite]

John - The 6 fuses in the center of the 26 fuses are spares, and only 19 of the 20 circuits are active after the removal of the immobilizer. This site has pretty good info for a Sigma fuse box if you wanted to compare it to the Duratec setup: https://www.lastsuperseven.co.uk/2022/08/fuse-box-arrangement.html?m=1

Edited November 4, 2022 by 11Budlite

[JohnCh]

I planned to do a temp install of the engine over lunch today to help me sort out available space for my non-standard items.  Of course, Caterham forgot to include the bolts that attach the engine mounting bobbins to the chassis and the size is not listed in the various build manuals I have on hand.  Based on the size of the holes in those mounts and the matching holes in the chassis, it looks like either M8 or 5/16".  Opting for the former, and buying suitably sized fasteners, I discovered that when Caterham punched the hole in the bottom of the side skin for those fasteners, they drove up some of the aluminum skin several mm into the holes.  This shrinks down the bottom of the hole to something that can only handle an M6 or 1/4" fastener.  That seems too small for an engine mount.  Can anyone confirm it the larger size is correct and if I'm supposed to drill out superfluous side skin material from underneath?  The photo below is representative of all 4 holes.

 

 

Thanks,

John

[MV8]

The 2015 assembly guide for a 420 shows M8x40 cap screws to 20nm with nylocs. A 3/8 bit can cut the shoulder so you don't remove the paint trying to remove the insert of you want to go with 5/16 grade 8. If concerned about strength, use socket head screws or metric 12.9 or sae grade 8, partially threaded and a same grade nut.

[JohnCh]

Thanks @MV8 I missed that when digging through that version of the manual, but it is the size I initially bough.  Bruce Beachman also got back to me quickly, confirming the size and that I will need to drill into the side skin.  

 

-John

[JohnCh]

Drilling out the side skin to clean up the holes was uneventful.  With that blocker out of the way, I decided to try the temp engine install again after work.  Based on everything I've read, installing the engine is tight in these cars, but I assumed that since I wasn't installing the engine/gearbox unit, and simply the long block, this would be easy.  Just drop it straight down.  Well...no.  Doing it solo was a lot fiddlier than I expected.  I couldn't just drop it down, but rather had to move the block fore and aft as I slowly lowered it down while simultaneously pandering to my paranoia about damaging my new car. 

 

Once the engine was roughly in place, and the RH mount could be reinstalled (otherwise, chassis tubes are in the way), I discovered it was impossible to get both engine mounts to align.  With one side aligned, the other was always slightly out.  It was close, but not close enough to force the issue.  Surely, I was missing something?  I kept at it, willing chassis tubes and the engine to occupy the same space at the same time but was unsuccessful.  Then I had an epiphany.  Well, more of a hypothesis that made me swear up a storm in anticipation of being proven correct.

 

 

Caterham uses the Raceline dry sump system.  To keep it simple, I bought the Raceline dry sump system for this engine.  Raceline and I had many conversations about my project, and I obtained a lot of parts from them.  i.e. they knew this was going in a 2022 420R SV.  It turns out the front of the dry sump pan they provided extends out from either side of the block by about 35mm more than their pan fitted to the Caterham 420 engine.  The extensions contain through-holes that appear to be engine mounts for a different installation.  With that extra material in place, engine installation is a physics impossibility.  Tomorrow, I break out a hacksaw and files.  Tonight, I open a Guinness.  Or two.  Or...

 

 

-John

[MV8]

An oscillating tool is great for tight spots that a hack saw, band saw, or reciprocating saw can't reach. Works fine for cutting aluminum with the right blade. I use normal tools for the most part then a sonicrafter for the last little bit. All the major tool mfgs sell their own version these days.

[JohnCh]

Great suggestion @MV8.  I forgot I bought an oscillating tool a few years ago to help with some corner sanding.  After wrapping the engine in plastic to ensure no aluminum shavings would work their way into places they don't belong, the metal blade produced a clean, accurate cut.   Photos below show the end result and the extra space created in the engine bay.

 

 

 

The next attempt at the temporary install was much, much quicker.  It looks like I'll need to shim out the right-hand engine mount from the block to get the engine mount to line up with the chassis holes, but it's only off by about one washer thickness, so should be straightforward.  

 

 

 

 

 

Less straightforward is engine to bonnet clearance.  With the oil cap removed and the bonnet resting on that mating surface, the bonnet was sitting about 2mm above the side skin.  It looks like a modified cam cover is in my future.  Raceline sells one that will work height-wise, but their webpage states it's designed to be used with standard Ford coil pack and that coil-on-plugs can't be used.  However, one of the three photos shows the cam cover installed in a car with COP in place, so clearly it can be done.  Are there any other options out there?  I seem to recall that Birkin has/had one?

 

 

 

-John

[MV8]

Too bad it's not easy to take a 1/4 inch out of the trans mount so the engine could also be brought down a 1/4. There should be some clearance for engine movement under load. Funny to watch dyno runs of various machines and how much the engine flops about.

[11Budlite]

John - Your build is looking good so far. There are all kinds of little fitment issues when putting a Caterham together, but none that can't usually be solved with a little fettling. Just a heads-up, when I first tried installing my gearbox in the trans tunnel I wasn't happy with the amount of clearance between the tailshaft hsg and the spaceframe. Because I didn't want to scratch the powdercoat/paint, I ended up removing a section from two unused bosses on the tailshaft hsg. I've attached a couple photos to show you the location.  

[JohnCh]

I took a look at the engine mounts yesterday with that thought in mind.  It looks like 3mm could be shaved from the bottom of the arms that bolt to the block, and the rubber bobbins could potentially have another 5mm shaved from them.  Not sure if that would be a good or bad idea, but then there is the trans mount which I have yet to examine.  And with engine rocking, some buffer is desirable.  I know there are other people out there running the 2.3L in an S3 without the shortened valve cover but not sure if they live with the occasional interference or if chassis-to -chassis differences and changes over the years contribute to the extra space.  Can anyone comment?  

 

Thanks,

John

 

 

[MV8]

That's how I'd lower the front, but only if I could get the trans down the same amount to keep the same (but lower) relationship to the pinion and front and rear joint angles that are slightly greater but still cancel. If they had added a 1/4 inch somewhere (1/8 to the cowl/bonnet, an 1/8 to the vertical rails) I don't think anybody would cry foul for ruining the lines. Could be tolerances from one chassis to the next.

[JohnCh]

It occurred to me that the bonnet is pretty floppy, and the measurements taken earlier were without the nosecone in place, which might lift the front of the bonnet.  Turns out it does.  It appears that before any foam rubber is added to the nosecone lip that supports the bonnet, I've gained another 5mm.  If I can replace the oil filler cap with a custom version that doesn't extend over the lip, or if it does, shave the lip down by that same thickness, I'll be fine as-is.

 

 

 

-John