2021 Caterham CSR "CatKong"

[Croc]

2 hours ago, KnifeySpoony said:

But why would they offer a painted CF rear wing? Presumable the only reason to spec that is for weight saving (IE not cosmetics)...

Yes the thought did occur to me but I have not seen one of these in person to find out if it is truly carbon all the way through.  You would hope so for the money....

[Croc]

36 minutes ago, Bruce K said:

Au contraire, my friend.  Caterham's F1 experience taught them that inboard coilovers created less drag, and that flattened-profile front wishbones further enhance the effect.  Less drag should mean faster top end.  In my comment, I was inquiring as to whether these CSR enhancements actually improve the top speed.  

 

Oh come on Bruce!  We are talking about a brick in aerodynamic terms.  Inboard or outboard coilovers is like asking whether I am more sporty naked or in full body suit lycra.  End result is still pretty ugly....

[Bruce K]

10 minutes ago, Croc said:

 

Oh come on Bruce!  We are talking about a brick in aerodynamic terms.  Inboard or outboard coilovers is like asking whether I am more sporty naked or in full body suit lycra.  End result is still pretty ugly....

Agreed - neither a pretty picture, nor a slippery shape.  But still, the CSR changes were adopted (in part) for the purpose of improving the brick's efficiency in the air.  My question was:  Have you noticed an improvement?  From your response, I presume the negative.  Perhaps it is too soon to conclude, as you have not had much opportunity to drive your CSR.  If so, let us know after you get it on the track (what a day that will be - I am happy for you in advance!)

[JohnCh]

@Bruce K the inboard front suspension was driven by ride and handling improvements, not an effort to increase top speed.  See this PDF from Multimatic about the CSR suspension project scope and targets. A more aerodynamic brick is still a brick   BTW although Multimatic did do aerodynamic analysis as part of the larger project, my understanding is that was focused on reducing lift, not drag. Someone else may know definitively.  

 

-John

[Croc]

39 minutes ago, Bruce K said:

Agreed - neither a pretty picture, nor a slippery shape.  

 

Bit harsh.  You drop me out of a plane I am aerodynamically good for 140mph.  Caterhams are no faster.

 

 

 

39 minutes ago, Bruce K said:

But still, the CSR changes were adopted (in part) for the purpose of improving the brick's efficiency in the air.  My question was:  Have you noticed an improvement?  From your response, I presume the negative.  Perhaps it is too soon to conclude, as you have not had much opportunity to drive your CSR.  If so, let us know after you get it on the track (what a day that will be - I am happy for you in advance!)

 

Marginal - not noticeable.  I suspect most of the hype was marketing driven.  My current CSR was put in a wind tunnel in 2012.  The chin spoiler (not standard - my addition) did reduce front end lift.  The canards/dive planes were too small to register.  A diffuser was very helpful but then you messed up the front end by adding rear downforce.  The flat undertray was helpful but then you fried your elbow from excess transmission tunnel heat.  The trick air diversion from radiator exit over the bonnet was negligible  A decent benefit comes from just using a tonneau on the passenger side but any Caterham can do that.

 

The benefit is all in the suspension.  The aero trickery is worth zero.   Over 10,000 miles of track driving with seat of the pants experience.  Back to back testing in 2014 at Donington showed the CSR is 1 second quicker in my hands over an identical engine/gearbox/tires deDion SV Caterham.  It all came from me feeling more comfortable with the car at the limit - the CSR was settled on the limit unlike the deDion.  Same day proved the SV was faster than the S3 chassis - all because of wide track suspension.

[lucky dawg]

3 hours ago, KnifeySpoony said:

That's interesting about the rear wings. I can see about exposed carbon rear wings having a glass underlay for strength or something. But why would they offer a painted CF rear wing? Presumable the only reason to spec that is for weight saving (IE not cosmetics)...

Paint is relatively cheap, while the clear coat needed to protect carbon fibre from UV caused damage is obscenely expensive. For example the standard removable roof on the C8 Corvette is CF painted body color. To have it exposed is a $2500 option. Similar story for the mirrors. 

 

CF Clear Coat Cost 

Edited March 1, 2022 by lucky dawg

[Bruce K]

Well, there's my answers.  I raised the subject because of comments I read in articles about the CSR, including comments on the aero-shaped wishbones.  I love the CSR concept - it's a Brunton without the weight incumbent to an LS motor (heavier motor, twice the exhaust system, more weight in the chassis).  The CSR still handles like a lightweight, but with the handling improvements of F1-style inboard suspension, stiffer chassis, fully-independent suspension, wider rubber and more.

[Bruce K]

Croc originally posts:

"Inboard or outboard coilovers is like asking whether I am more sporty naked or in full body suit lycra.  End result is still pretty ugly.... "

1 hour ago, Bruce K responds:

    "Agreed - neither a pretty picture, nor a slippery shape."  

Croc responds:

 

"Bit harsh.  You drop me out of a plane I am aerodynamically good for 140mph.  Caterhams are no faster."

 

Bruce's rejoinder:

 

"Human terminal velocity (without a speedsuit) is actually 120 mph, while many brick-like Cats can hit 140 or more.  And I did not mean to disparage your sleek proportions - it's just that my sense of manlihood prevents me from commenting favorably upon the vision of an unclothed Croc flying through the air with his stick shift flailing."

 

 

 

Edited March 1, 2022 by Bruce K

[coffee break]

OK guys, somethings are hard to "unread"

[Croc]

 

More progress this week.  The immobilizer accidentally dropped off the car.  These are automotive security devices essential in the UK given the high rate of crime present and the current inability of the UK to send convicts to Australia.  They work to provide a complete circuit when a key fob sensor is in close proximity to a receiving sensor mounted on the steering column.  With this then power is provided to the electrical circuits to allow the car to start. 

 

In reality, most US builders of kits just tie wrap the key sensor to the steering column next to the receiving sensor so that it is always on since the USA does not have anywhere near the level of crime and thievery seen in the UK.  Something to be said for the Second Amendment I guess?  

 

We could have put it back on but decided not to.  Its just extra wiring complexity and a likely future failure point.  Quite an intrusive piece of kit when seen in isolation.    

 

[Croc]

With the wiring advanced far enough, it is time to wire in the wheel sensors needed for measuring wheel rotation speeds for launch control, traction control and the ABS brakes.

 

This is the right rear.  Brackets for the sensors now mounted on the hub.  As a reminder, the CSR chassis is independent rear suspension.  These hubs will look nothing like what a de Dion rear end car will have.  The IRS was reputedly derived from a 1990s era VW Passat sedan.  The rear uprights are pretty tall when you see them.  To this a custom wheel hub is mounted onto which the brakes/wheel assemble.  This hub was reputedly developed by Titan Engineering for Caterham or so I was told once.  

 

 

 

Lots of measuring is involve to ensure no interference with the suspension but yet close enough to the reluctor wheel to ensure optimal contact.  The photo below shows the precise tolerances needed for this to work.  These wheel speed sensors are quite large compared with the usual speedo sensor that Caterham would provide.  The reluctor wheel is the "cogged" tooth around the drive shaft (the thing with the rubber boot).  These were 3D printed in plastic for trial fitting and then sent to a professional to mill out of metal.  

 

 

With that the right rear suspension can be mounted on the car.  

 

 

Next step is left rear suspension.  Much easier second time around.  

 

 

[SENC]

And here I've been thinking traction control and launch control was a function of the right foot!

 

Cool stuff, thanks for sharing!

[Kitcat]

Or, just drop in an X-flow, and say goodbye to traction problems!

 

Kidding, of course. It’s very impressive that Beachman Racing and you are engineering a one-off traction control system exclusively for this single car.
 

Is this the last big challenge on getting this SuperCat ready for the road/track?

[Vovchandr]

Mo power

Mo problems 

 

with that said we all want more power 

 

 

[John B]

[Bruce K]

10 hours ago, Croc said:

With the wiring advanced far enough, it is time to wire in the wheel sensors needed for measuring wheel rotation speeds for launch control, traction control and the ABS brakes.

 

This is the right rear.  Brackets for the sensors now mounted on the hub.  As a reminder, the CSR chassis is independent rear suspension.  These hubs will look nothing like what a de Dion rear end car will have.  The IRS was reputedly derived from a 1990s era VW Passat sedan.  The rear uprights are pretty tall when you see them.  To this a custom wheel hub is mounted onto which the brakes/wheel assemble.  This hub was reputedly developed by Titan Engineering for Caterham or so I was told once.  

 

 

 

Lots of measuring is involve to ensure no interference with the suspension but yet close enough to the reluctor wheel to ensure optimal contact.  The photo below shows the precise tolerances needed for this to work.  These wheel speed sensors are quite large compared with the usual speedo sensor that Caterham would provide.  The reluctor wheel is the "cogged" tooth around the drive shaft (the thing with the rubber boot).  These were 3D printed in plastic for trial fitting and then sent to a professional to mill out of metal.  

 

 

With that the right rear suspension can be mounted on the car.  

 

 

Next step is left rear suspension.  Much easier second time around.  

 

 

My Lord - this car should no longer be nominated  a Caterham.  How about McClareham?  Caterrari?  Caterghini?  It is every bit as exotic, and much rarer than the marques which inspired my suggestions.  And - I bet it will be faster on any short, and many medium length, tracks - maybe better than that!  My 935 Tribute is one of fewer than 2,000 in the world, and I thought that was rare.  In terms of uniqueness, my car is peanut butter compared to this CSR's beluga caviar.  Croc - I wonder if the extreme custom nature of this car will prevent you from extracting the full 10/10th's of available performance.  I didn't intend it, but that's happened to me with the 935, and is the reason I bought my R400/500 Cat.

Edited March 7, 2022 by Bruce K

[Croc]

16 hours ago, Kitcat said:

It’s very impressive that Beachman Racing and you are engineering a one-off traction control system exclusively for this single car.
 

Is this the last big challenge on getting this SuperCat ready for the road/track?

 

Its not the only CSR with this level of sophistication.  However, its the only one in the USA.   The hardware of ECU and peripherals can be bought along with the software to operate it.  The custom piece is installing brackets and calibrating it all to the precise tolerances required.  Its a learning curve but one that will allow it to readily replicated in the future for customers (called JohnB?) that come along later.

 

There still are a number of challenges left:

• The Sadev gearbox has to be integrated with the ECU.   In my last two visits to the workshop in the last 2 weeks Bruce and I worked out we were missing a hardware element I forgot to buy and also buy another piece that may have got lost in the workshop.  We need the various wiring pieces to connect gearbox, ECU and dash - they are on the way.  This is important as we have pneumatic paddleshifters actuating gear changes.  There needs to be a clutch actuation system plus a throttle blipper for the downshifts and a throttle interrupter for the upshifts.  All these need to be centrally integrated by the ECU so that it controls all the inputs in harmony.  This has all been done before in the UK but not here so learning curve time to make it all work correctly and reliably.  The ECU can do this but it needs setting up.
• At this point the car assembly can really move forward - fueling system installed, engine and gearbox in, plumbing of oil and coolant lines, finishing off the wiring, etc.  
• The engine has run on a test bed dyno but has not been properly tuned with the end ECU.  So that needs to happen.  The MBE ECU has a base Duratec tune but this will need to be properly remapped.  While it is an MBE ECU, it is not a Caterham supplied one so is not locked.  Somewhere around this point the OBDII output needs to be configured.  
• A lot of the systems will need calibration and documentation.  The dash set up will require setting each of the multiple digital screens accessed by buttons around the edges of the digital dash.  The primary screen with summary info will need to be set up.  Ranges established around each of the monitoring input so that this portion of the screen will light up the moment something goes outside a preset range, e.g. voltage drop or oil pressure drop.  Buttons need to be mapped to functions based on how I will use them.  This could be time consuming but AIM has a new piece of set up software and we are not the first to set up a digital dash on a Caterham.
• Then the hardest piece will be drive testing.  For example, we need to dial in the active suspension settings. We have a baseline view based on the mathematical set up but there will need to be tuning off this baseline from driving the car on a track.  I like this work since I spend plenty of time tuning suspension on track in my other cars.  The gearbox shifting will need to be set up.  Only way to do this is drive the car hard.  While I could do this, the better solution is Bruce will do it since he knows the local tracks in Seattle and I don't.  Local knowledge and familiarity allows him to be much faster and better than me at it.  If we were east on my home tracks it would be the other way around.  

 

The process in many areas is that Bruce and I have spent time talking through and strategizing each of these points, then I have gone off to research the technical aspects for him, then we further strategize and adjust the game plan based on the additional technical input, then he completes the actual work step.  New things often get discovered at this point requiring a course change.  Its been a fascinating project for both of us.  A lot has been learned.  If Covid had not come along we would likely have been finished by now.  The key word on this project is patience as this is not plug and play first time around.  But it will be for the next person who wants to come along and top this project.  

[John B]

What a fascinating project! It's a pleasure watching vicariously as it progresses and I can't wait to see the finished result. 

 

 

[Croc]

 

The front wheel assembly is now coming together with the wheel sensors.  A milled reluctor wheel for the front wheel has been designed and fabricated to drop inside the front brake disk.  Next step is disassembly, zinc-coat the reluctor to protect it and then final assemble.

 

 

 

Following on from last week, the rear suspension assembly can move forward by sorting out the remote reservoirs for the rear shocks.  Holes made to bring the reservoir into the boot area and they will be bolted to the boot floor.  

 

 

[Renottse]

Question @Croc about the tractive suspension fine tuning. Will it be the mechanical adjustment only? Or, does Bruce have the ability to make adjustments to the tractive control unit programming?