520R SV build has commenced

[windsurfer]

Your dash setup looks very clean, thanks for sharing the drilling method. I still have a blank carbon dash (from Westermann too)to be cut for my switch and gauges. I was heading for a 620r style dash as you did but will probably keep my original square switchs (like a 420r) Last time calculated all the bits an pieces required, the total cost was pretty high... but it is probably easier to drill a square hole than cutting a square one. Will see if I find some parts that could be working for a look alike setup. But it does look very nice!

 

Will the 420r exhaust system (cat and exhaust piping) will still work with your increased output or it will be limitative?

 

 

 

 

[JohnCh]

The Caterham prices are on the high side.  Those same switches (Apem) are available for less from other sources such as Car Builder Solutions in the UK or through various electrical supply houses in the US.  

 

The stock exhaust will hold things back.  In theory it will cap the fun in the 250-260hp range, which is fine for now.  Phase 2 of the build -- if needed -- will be a custom exhaust and appropriately sized Raceco silencer which should increase power potential to the 270-280hp range. 

[windsurfer]

3 hours ago, JohnCh said:

The Caterham prices are on the high side.  Those same switches (Apem) are available for less from other sources such as Car Builder Solutions in the UK or through various electrical supply houses in the US.  

 

The stock exhaust will hold things back.  In theory it will cap the fun in the 250-260hp range, which is fine for now.  Phase 2 of the build -- if needed -- will be a custom exhaust and appropriately sized Raceco silencer which should increase power potential to the 270-280hp range. 

Thanks for the link to car builder solutions John.

[Alex-Ks1]

What exactly comes in a kit from the manufacturer? And why does it take so long for you to receive it ?

[JohnCh]

The kit includes all the parts necessary to build a running car.  Lead time is a combination of demand outstripping supply which results in a waiting list, supply chain issues, and my opting to wait another few weeks to ship with two other cars and save several thousand dollars in shipping costs.  

 

If you want to learn more about the Caterham assembly process, from what the build entails to all the included parts down to the fasteners, check out the latest build manual and the detailed build blog linked to below.

 

Caterham Assembly Guide v2.3

 

Caterham Detailed Build Blog

 

 

-John

[JohnCh]

Anyone who has removed the honeycomb boot floor can attest that it's an exercise in frustration.  It's one of those there-is-absolutely-no-way-in-hell-that-can-wiggle-out-without-bending-something moments until suddenly….it's out.  Looking at the supporting frame, there is no apparent reason why Caterham doesn’t simply cut the floor into two pieces so it's easy to remove and install when you need to access the fuel tank.  Since they didn’t bother to do it, I did.  

 

This was my first experience cutting honeycomb. It turns out that when using a thin jigsaw blade, the blade can twist within the honeycomb, creating a bevel cut and pulling the saw into the guide while slowly pushing it over despite the use of clamps.  Unfortunately, I didn't catch this early and ended up with a cut that is anything but straight.  Not a big deal given it's only a cosmetic issue and isn't visible when the boot carpet is in place.  The honeycomb floor is now quick and painless to remove and there is no impact to the rigidity of the floor.  

 

This photo shows the right side of the rear frame for the boot floor.  The red line on the tape shows where the two sides will meet once it's cut in two.

 

 

The next two photos show the boot floor after the cut.  First, with just the right side in place, then with both sides.

 

 

 

With boot floor cut and fuel plumbing work done in the back, it was time to install the rollover bar.  Taking a tip from a build blog, before blocking access with the bar, I ran a harness bolt into each harness fitting to make sure they weren't gummed up by paint.  They were fine, but it was clear the person who drilled the aluminum strip in the back of the boot cover that sits over those holes was having a bad day.  The holes for the passenger harness bolts were partially blocking the threads, and it appears they tried drilling those holes a few times, because they were not a shape one would confuse with round.  Removing it from the car then cleaning things up with a file and it was time to install the rollover bar.  

 

As others have found, bolt alignment was off.  In my case, a pair of ratchet straps were required to move things around enough to get all six bolts in place.  Tomorrow I'll drill the holes for the 3rd brake light and prep and paint the aluminum mount.  

 

 

-John

[CBuff]

John,

 

I have been researching the 3rd brake light options. Most seem to mount to the roll bar or X within.  Since I have spec”d a painted (grey) rollbar I don’t want to run the wire along the bar. Are you planning on plumbing the wire inside the bar itself ?  In reading some of the blogs it seems most people don’t do this. If you do plan on doing that, I would be interested in any challenges related.  Some folks don’t like the idea of drilling into roll cage for structural reasons. I wouldn’t think it would have much impact but defer to the more experienced here. 
 

Another option I came across was the brake light on the boot. https://caterhamparts.co.uk/rear-lights/6703-high-level-brake-light-2017.html
 

didn’t know if this would be high enough to be useful.  

[JohnCh]

I live in a world of SUVs driven by smart phone using, latte swilling, multi-taskers who consider themselves exemplary drivers.  I want to mount that third brake light as high as possible. 

 

For the Caterham I'm using this setup from Beachman Racing:  http://www.beachmanracing.com/rollbar-mounted-light.  It requires 4 holes drilled in the bar; 2 for the mounting screws and 2 for the wiring.  This is similar to the setup I have on the Westfield.  I'm not concerned about impact to structural integrity.  The holes are small.  If I'm in an accident involving sufficient damage that someone would even raise that question in the post-accident investigation, I figure I'd be dead whether the holes were there or not.

 

Threading the wire through the bar in the Westfield was a challenge, but it was doable.  I suspect the Caterham will be similar.  I'll post the process once I get to that point.

 

-John

[Croc]

6 hours ago, JohnCh said:

I live in a world of SUVs driven by smart phone using, latte swilling, multi-taskers who consider themselves exemplary drivers. 

 

Strangely enough I find the drivers around your town really good but then I am comparing to NYC driving standards!  

 

 

7 hours ago, JohnCh said:

This was my first experience cutting honeycomb. It turns out that when using a thin jigsaw blade, the blade can twist within the honeycomb, creating a bevel cut and pulling the saw into the guide while slowly pushing it over despite the use of clamps.  

 

 

Oh I feel the pain.  I destroyed saw blade after saw blade trying to do a straight cut on my first time.  Infuriating material to work with.  

[Alex-Ks1]

about NY drivers, kansas must have the worst, at the DMV if they ask you if you tail gate and you say NO, they won't give you the license. They tail gate at every speed, I hate it, they pass on the right, go through red lights, pass on a road shoulder!!!. cross double yellow lines, the worst, 

To combat the fools , on my F250 the trucks sits high. in the back F350 rear springs. And a 250 lbs rear bumper I made from 3/8 plate steel . and I have a brake light kill switch. When I hit the switch and stand on the brake peddle they slam into my rear, nearly destroying their car.  I don't care at all, and on the bottom of the bumper is a 2 ton pintel hook,for towing my 20 ft Trailer. That does the most damage, and they get the ticket, following to close . 

  When I was out in my 7, I had a clown following to close , at a light , I got out walked up to his stupid Honda and told him , " do it any more and Ill knock you into next week, " He stayed far back after that 

Edited January 8, 2023 by Alex-Ks1

[JohnCh]

This morning I heard back from SBD about using a fuel pump with pressure regulator rather than adjusting pressure via PWM control of the pump.  I don't have the specifics yet but will share them once I get to this part of the project.  Good news is that it sounds simple: 

"you will just have to move one of the pins in the ECU wiring hood, which is a very simple process on a MBE9A4 ECU, because the pin that controls that the digital pump controller is different to the one you would need to control a relay that can energise the standard pump. You will also need to fit just a standard 30amp relay."

-John

 

[windsurfer]

On 12/30/2022 at 7:24 PM, JohnCh said:

The hole for the steering column is offset by 1/3", the shape was off and required removal of 1/8" - 3/16" of material around the shoulders of the dash so the scuttle would fit, there are few places where mold surface imperfections are visible when the light hits it just right, and the surface was scuffed.

I've checked with mine and it looks like I have the same offset. The quality of the finish is pretty good howerver. 

 

best regards

[JohnCh]

A few random updates I'll break into two posts.  First, the 3rd-brake light is installed.  I purchased an unused Beachman Racing setup from someone on the forum.  The mount is beautifully machined from aluminum and is normally installed in its natural state, but having that as the only piece of brightwork on the car seemed a bit out of place.  A light sanding, then shooting it with primer followed by Rustoleum Satin Black which is a decent match for the powder coating used by Caterham, and it blends in with the rollbar.

 

 

Running the wire through the rollbar was not as daunting as it sounds.  I ran safety wire, which is thin yet stiff, from the exit hole on the bottom of the rollbar up to the entry hole on the top, grabbed it with a pick, pulled it to the hole, then reached in with forceps to grab the wire and pull it out.  Wires from the light were then twisted to the safety wire and sealed together with adhesive lined heatshrink to avoid separation in the middle of the rollbar, and finally the whole affair was pulled through the rollbar.  Drill holes were  painted to prevent corrosion and the holes were sealed with liquid gasket to prevent water ingress.  Worked great.

 

 

 

 

When buttoning up the rear suspension, I discovered an interesting problem with the axle nuts.  These are handed with left-hand threads on the driver's side and normal, right-hand threads on the passenger side.  The bottom of both nuts were 41mm, but the top of each was larger and required a 42mm socket to engage the full height of the nut.  The delta between top and bottom was larger on the driver's-side nut and this difference was visible to the naked eye.  Not a problem per se, but I don’t' recall seeing this in the past with any nuts.  Once a 42mm socket arrived, they went on without issue.  The photo below shows the driver's side nut dropped into a 41mm socket, with the greater than 41mm portion sitting above the surface.

 

 

-John

[JohnCh]

Like on my Westfield, some of the electronics are controlled by switches on the steering wheel.   However, unlike the Westfield where these switches are hardwired with a coiled cord running from the steering wheel hub to the back of the dash, for the Caterham I'm using the Freewheel kit which is wireless and has some PDM control.  Green buttons are turn signals which self-cancel based on an adjustable timer and pressing them concurrently triggers the hazards.  The blue button toggles between high and low beams when the dash mounted headlight switch is on or operates as a flash-to-pass button when that switch is off.  The small black button will either be used to control the resettable trip odometer or single wipe functionality.  The single wipe function is more interesting but will be seldomly used, whereas the trip odometer is used every time I fill up the tank.  With the AiM, you either need to go through a few menus to reset it or install a dedicated shortcut button.  Since I want that one push experience, it's either add it to the dash or the wheel.  The large black button in the center is the horn.  I'm having the Caterham 7 logo laser engraved on it which will make it look more intentional.  Although I'm using this same switch on the Westfield, the steering wheel spokes on that car are true black, unlike the very dark gray of the Momo, so the button doesn’t stand out to the same degree.  Hopefully the logo makes it visually more interesting.   

 

My initial plan was to make the switch holder plate out of aluminum, but I went down the rabbit hole of drawing it in CAD and 3D printing a mockup to visualize it and play with button locations to ensure they are comfortable for me to operate.  I then realized 3D printing gives me additional flexibility for wire management as I can print in channels to hold the wires then small cover plates to hide them from view.  The final version will be printed with more care and should look good in the carbon fiber nylon used elsewhere on the car.  I'll post pictures of the wire management later.

 

Lastly, I played around with making a low-profile oil filler cap.  The rough mockup works surprising well.  I need to make a very minor tweak then print it with finer resolution settings out of the carbon fiber nylon, but I think this is the direction I'll go.  Although I'm not a fan of an oil filler cap that requires a tool, the square shape is sized to fit a 3/8" driver.  Since I always carry tools with me, I will always have one of those in the car.  I may also print up a small tool that I mount under the bonnet to make it even more convenient. 

 

 

I'll post more updates this weekend after the engine and transmission are in.  I've already had a few interesting discoveries with that process. 

 

-John

[CBuff]

2 hours ago, JohnCh said:

A few random updates I'll break into two posts.  First, the 3rd-brake light is installed.  I purchased an unused Beachman Racing setup from someone on the forum.  The mount is beautifully machined from aluminum and is normally installed in its natural state, but having that as the only piece of brightwork on the car seemed a bit out of place.  A light sanding, then shooting it with primer followed by Rustoleum Satin Black which is a decent match for the powder coating used by Caterham, and it blends in with the rollbar.

 

 

Running the wire through the rollbar was not as daunting as it sounds.  I ran safety wire, which is thin yet stiff, from the exit hole on the bottom of the rollbar up to the entry hole on the top, grabbed it with a pick, pulled it to the hole, then reached in with forceps to grab the wire and pull it out.  Wires from the light were then twisted to the safety wire and sealed together with adhesive lined heatshrink to avoid separation in the middle of the rollbar, and finally the whole affair was pulled through the rollbar.  Drill holes were  painted to prevent corrosion and the holes were sealed with liquid gasket to prevent water ingress.  Worked great.

 

 

 

 

When buttoning up the rear suspension, I discovered an interesting problem with the axle nuts.  These are handed with left-hand threads on the driver's side and normal, right-hand threads on the passenger side.  The bottom of both nuts were 41mm, but the top of each was larger and required a 42mm socket to engage the full height of the nut.  The delta between top and bottom was larger on the driver's-side nut and this difference was visible to the naked eye.  Not a problem per se, but I don’t' recall seeing this in the past with any nuts.  Once a 42mm socket arrived, they went on without issue.  The photo below shows the driver's side nut dropped into a 41mm socket, with the greater than 41mm portion sitting above the surface.

 

 

-John

Third Brake lights looks great. I have been trying to think about how to do this on my yet to be built or delivered 420. How did you drill into the roll bar? Just a punch or did you vice something to the bar itself (Likely overthinking a lot of this). And you just wired into the existing brake light harness by the right rear wheel? Any issues with the light and weather gear clearance/visibility or interior reflections - not sure how much night rain driving you plan on doing. I was thinking of including a switch on that electrical run to disable it in the very of chance I would not want it to illuminate. Again, over thinking everything 

[JohnCh]

I did the following:

• Blue tape on the rollbar where the mount would go, then put a level on the rollbar, and clamped the mount in place when the level on that part was the same as the rollbar. 
• Marked the holes with a pencil, removed the mount and punched the center of one hole.  Drilled that hole (it's for an M5 screw as I recall), and tapped it. 
• Put the mount back on with one screw, used the level again to ensure the other hole was still properly marked with that one side already fixed and repeated the drilling and tapping process for the second screw.  

Bruce and Caterham sell a sub loom that inserts between the rear light connectors.  However, I've have read that a dedicated wire may already be in place for this on current cars.  I haven't checked yet as I haven't completed the final wiring which will include a Backoff module that flashes the 3rd brake light a few times on initial brake application.  I have something similar on the Westfield; based on experience, it definitely gets people's attention.  I need to tie up some things before adding the battery and energizing the system to check the connections and complete that work.

 

I was told this brake light assembly fits with the hood in place but haven't confirmed if that's true.  If not, I'll deal with it.  I don't anticipate ever using the full hood as I much prefer a halfhood and those can be made to accommodate a light in that area.

 

-John

[bball7754]

When third lights first appeared for Seven’s, it seemed that no one was drilling their roll bars and were attaching both the light and wires using zip ties.  The reason, as I remember, was that if you tracked your car, it would fail tech with a roll bar that had holes drilled into it.  As I disliked the esthetics of the zip ties, I never added the third light.  And I realize that my safety should have overridden cosmetic concerns, but…..what can I say. 😊

 

So, I guess the “fail tech” issue was false, or the requirements to pass tech have changed?  Or maybe it was just if you were racing, rather than track days?

Oh, and the install looks great!

 

Steve

[CBuff]

I have been looking through rules and regulations (Mostly NASA as that is what I have been driving). While they don't stipulate anything specifically as far as any holes being drilled into the Roll Bar for HPDE events, again mostly what I would be doing, they "may" require for TT and other events that a 3/16" hole may be drilled for the purpose of inspecting the roll bar thickness (see wording below). Since the roll bar doesn't meet the roll cage requirements anyway its a moot point but I would make the argument that if they might require drilling a 3/16" holes to inspect they wouldn't object to a hole of that size being there to begin with. Not sure what qualifies as "non critical area" Defer to those more experience and it seems like tech inspection isnt always cut and dry. Not sure about other sanctioning bodies.

 

15.6.20 Inspection (For Racing)

Wall thickness will be determined using a tool such as a sonic tester. Alternatively, a 3/16 inch inspection hole may must be drilled in each of the required bars in a non-critical area for the purpose of determining wall thickness.Determination of wall thickness and means of testing will be noted in vehicle logbook. All welds, except those mounted to plates on the floor, must be accessible for inspection (360 degrees).

https://nasa-assets.s3.amazonaws.com/document/document/282/2023.0.pdf

 

Should my car ever arrive, I think I will plumb the 3rd brake light thru the bar - similar to John.

[Croc]

17 hours ago, CBuff said:

While they don't stipulate anything specifically as far as any holes being drilled into the Roll Bar for HPDE events...

 

 

My Caterham roll bar (FIA/track day with double diagonals) has the two inspection holes drilled as standard.  I bet that is the same if you ordered one new today. It is a UK racing requirement.  Are you sure yours does not?

 

My third brake light is wired inside the roll bar using a drilled hole.  No one has ever challenged it.  

[11Budlite]

Just for reference, my dual diagonal FIA track day bar that I got used from Seb doesn't have the holes drilled. It's a Caged item on a metric chassis.