520R SV build has commenced

[MV8]

There are at least a couple different tapes out there, but the common, white foam tape here doesn't allow removal of the weight from the tape and re installation with the same grip if any. It tears in the middle of the tape instead of releasing the fully cured (on the weight side) adhesive.

 

Adhesive weight tape stretches and the adhesive is much stronger than the tape. The weights are not ordered or limited on the rim size.

The installer gets one shot in applying the weight tape. If it has to come back off, it's not reusable without a lot of work to clean and install on new tape.

[JohnCh]

Hi @Rosteri I followed your earlier comment which is what led me to look specifically at that aspect on both the Caterham and Westfield.  Thanks for that!

 

1 hour ago, MV8 said:

The wheel was not clean and/or the weight installer was in a hurry.

 

Thanks for the tips on how to redo this without rebalancing, but this comment is why I'm considering it.  My confidence in the quality of the initial job is not high.  

 

[Alex-Ks1]

with that much weight in one place on your wheel, the tire is probably out of round . or slip it 180 degrees on the  rim, re balance . with that much weight in one place on the rim, at speed the car will shake the pain off the body. Who ever did this for you, does not know how to balance tires and wheels .

 

   PS. I bought black market plans for a Aerial Atom . thats the next project, V8, twin turbo . cant live for ever

[ashyers]

John,

If you rebalance the wheels it may be worth finding someone who will roadforce balance them. If properly done it works great! I’d do it for you if you were closer. Hunter did a great job on the roadforce machines, I suspect the math involved was a bit scary 🙂.

Andy

[JohnCh]

Thanks guys.  The shop I normally use for my cars does road force balancing and are really thorough.  I had considered using a different shop closer to home, but probably worth ensuring it's done right.  The plan is to have both front wheels redone and I'll instruct them to rotate the tires as needed to minimize weight and optimize balance.

 

In other news, still no word from Pegasus on air filter status despite calling when they opened this morning.  I'll try again tomorrow.  FedEx confirmed with Caterham that the seat runners and aero/windscreen quick change brackets are lost.  To Caterham's credit, they sent out the replacement items first thing yesterday morning and they arrived here about an hour ago; 1 day arrival from the UK.  Of course, the package looks like it was vigorously kicked around the FedEx facility, but fortunately nothing inside was fragile, so no damage despite their best efforts.  

 

-John

[KnifeySpoony]

Keep an eye on the position of the tire on the rim - if you're tracking it, you'll probably see that the tire walks on the rim. Because of this some people just static balance the wheel, then never balance again with the tire on, as the balance will shift over time. Obviously, you could rebalance after every trackday if you wanted too.

[MV8]

Stick-on weights will always be much heavier than the equivalent clip-on. The weight is radially closer to the wheel axis of rotation (less leverage) and since the weights are very thin, to get the required amount of weight means spreading it out. The further away from the point the machine says to add the weight, the less effective the weights are. If the machine cannot differentiate between clip on and stick on, the weight shown will be less than is actually needed, resulting in more spins and extra weights or wasted weights that need to come back off. There is a ruler that protrudes from the balancer to measure the weight location within the rim laterally and must be entered but it does not take into effect a radial measurement. I'm sure there are machines that do but I have no experience with them.

 

A square tire can be perfectly balanced and smooth on the machine. Some servicing companies used to remove or true out of round as an up sell but this is a bad idea as the tire when installed has been sitting on a rack (hopefully) and like any cold rubber, will hold that shape until hot and under pressure. The road loading method should address that.

 

None of these balance methods last for the life of most tires and need rebalancing with wear; especially typical wear along one shoulder due to a camber that doesn't "align" (see what I did there?) with the actual use.

 

 

[JohnCh]

My preferred shop can do the wheels at the end of next week.  The plan is to drop them off Thursday and pick them up either the next day or Monday.  

 

My no-logo air filter saga continues.  A few pointed conversations with Pegasus were required to go from the answer "ITG is prioritizing this" to receiving actual dates.  It turns out ITG made the initial error and did a no-logo filter on a JC55S rather than the JC50S I ordered.  Physically, the JC55 is 2.5" longer and a very tight squeeze.  ITG has already produced the correct filter (good) but then put it on a slow boat across the Atlantic yesterday (bad).  That's a 2+ week journey, plus time for Pegasus to receive, unpack, repack, and ship to me, which puts me at over 3 weeks before I can even begin to cut the bonnet.  Given the trickle-down effect from this -- I need the filter before I can start driving the car, find and fix any subsequent issues, adjust the tune, schedule a dyno session to finalize the tune, etc. -- that extra 2+ week delay could really impact my plans this summer.  Therefore, I decided to bite the bullet and have them send a logo filter today which will arrive in time for me to attempt the bonnet cutout next weekend.  Once the no-logo filter arrives, I'll have a very low mileage ITG JC50S-125 for sale at a good price.  Just in case anyone needs one.  

 

The order is in with Thundersport for a modified half hood that will work with the 3rd-brake light.  I was initially told that specific brake light works with Caterham's weather gear, which I took that to mean the factory half hood as well.  Bad move on my part.  Once I saw how the half hood attaches, it was clear the brake light would prevent it from cinching down.  Thundersport initially said they were unable to modify one to fit, but after asking if they could simply add a cutout for the light and stating I was fine if it wasn't quite as watertight in that area as normal, they agreed.

 

Thundersport also makes the transmission tunnel covers for Caterham.  When ordering my kit, I upgraded the standard faux carbon vinyl transmission tunnel cover to the black leather version from the Signature catalog and now need a matching piece of leather for my glove box.  Thundersport has agreed to include that with my order, eliminating the need for me to visit various upholstery shops trying to find something with matching grain and color.

 

-John

[JohnCh]

The front wheels have been rebalanced on a Hunter Road Force machine. According to the shop, some wheels have a slick-ish coating that must be cleaned off to avoid the weights falling off.  Apparently neither Caterham nor my dealer's shop cleaned them well enough.  I'll need to keep an eye on the rears to make sure those weights stay in place.  

 

The filter with logo arrived on Thursday.  First step was drilling the baseplate for the Jenveys.  One reason I chose the ITG over the Pipercross used on the Westfield, is the mounting system.  The extra height of the 2.4L, means mounting either brand right side up would place the 1/4 turn fasteners very close to the bonnet.  To eliminate any possible rubbing issues, my plan was to mount the filter upside down (one of the reasons I special ordered a no-logo version).  The bottom portion of the ITG mount is cleaner looking and more compact than the Pipercross.  Since that would be the top in my installation, I went with the more compact design.

 

A drill template for the various holes was printed to ensure that portion went well.  I still need to add 2 more holes for the air temp sensor but wanted to do that last since I knew room would be tight and I wanted to have the baseplate in place to figure out the location. 
 

 

 

 

-John

[JohnCh]

Those with better memories than mine may recall my initial plan was to build a cold air box fed by the intercooler scoop in the 620 nose cone.   Space challenges and concerns that the amount of air reaching each cylinder could differ significantly given the limited space available for the cold air box, led me down the path of that old standby: a sausage filter poking out of the bonnet.  Cutting the filter hole on the Westfield wasn't too hard given the bonnet is fiberglass; Get the hole reasonably close, then use a Dremel to carefully expand the opening until it's the right size and shape.  The Caterham's painted aluminum bonnet, however, seemed like a bigger opportunity for screw ups.  Let the anxiety begin...

First step was installing the filter and marking its location in relation to the bonnet with a combination of strings and marker lines on the side skin. Chip board (cereal box material) was then fashioned into a partial bonnet, and the strings and marker lines were used to draw a rough, slightly oversized representation of where the filter would poke through.  That section was cut out, the air filter was reinstalled, and the gaps to the filter were taped over then trimmed to shape.  

 

 

 

 

Next, the filter was removed, the bonnet installed, the chipbopard template laid over the top, and the shape of the cutout transferred to blue tape on the bonnet.  

 

 

This is where things got scary.  A rough cut was made with an air saw, then began an iterative approach of fitting the bonnet, marking where more material had to be removed, then using either the air saw, files, or a 60-grit flap wheel in a drill to make those adjustments.    

 

 

 

 

Finally, some rubber edging was used to seal the cut edges.

 

 

Next step is a test drive.

 

-John

[panamericano]

 

Is this a "Pride" thing?

[JohnCh]

Definitely not.  Flying a flag upside down is a sign of distress.  Mounting an air filter upside down is a sign of frustration; a word that describes a large part of my Caterham experience to date 

 

-John

[Bartman]

I am about to cut the same hole through the hood of my car, thanks for the images, it helps to give me confidence that I can do it without screwing it up to badly.

 

Jon

[JohnCh]

@Ferrino walked me through the process of using chipboard and recommended the air saw.  Both worked great.  If you are going with the big filter, I suspect an S3 will be a little easier since the filter pokes all the way through the bonnet necessitating a more uniformly oval cutout.  With the SV, the rear section is partially shrouded which creates a more complex shape that can quickly go from just a little tight to way too big given how the angles work against each other.  My best advice it to make the first cut intentionally too small, then put the bonnet in place to see if the location is off.  In my case, the front was perfectly located despite the undersized cut.  If I had cut the opening to the correct size in the first pass, the front gap would have been bigger than intended.  

 

-John

[MV8]

By making it a tight fit around the filter, that still leaves plenty of material to open it up for a scoop (like on Voyvchander's car), with room for engine movement/rocking under load plus a little forced air induction.

 

Where did you get the big sheets of kraft paper/chipboard? How heavy/thick? That material in layers would work well as a base for making thin, upholstered panels such as around the tunnel on older cats.

[JohnCh]

I've noticed a lot Caterhams have a very big gap, but I prefer keeping it tight, if for no other reason than the big gaps are another avenue for water to enter the engine bay.  Despite the very tight gap on the Westfield, engine movement has been a non-issue over the years. 

 

I had trouble finding larger pieces of chipboard locally, so I opted for these smaller sheets from Amazon and taped them together.  Worked fine.  https://www.amazon.com/dp/B07BYWG8N5

 

-John

[MV8]

No doubt taping works and no need for it now, but I just found "heavy builder paper" at HD in a roll, 3'x.061"x166' for $18. Used to protect laminate and hardwood floors during construction. The coated paper is also used for roof underlayment. I can think of a number of uses for that.

[JohnCh]

That underlayment is double the thickness of the chipboard, but clearly far more pliable given it's on a roll.  The next victim should give it a try

 

The half hood from Thundersport arrived today.  The cutout for the 3rd-brake light turned out perfectly.  I sent them a measured drawing and also photos with a seamstress tape measure showing the precise location from the windscreen frame.  As you can see from the photos, they nailed it.  I didn't expect it to come out so nicely given they weren't able to set hands on the car as per their original request; a proposal that was quickly dismissed once they understood the length of said drive  

 

 

 

-John

[JohnCh]

I was finally able to make time on Friday to pick up a 3-day trip permit.  To make monitoring things easier while driving, the AiM display was reconfigured to show both Lambda and the TPS load site outputted from the MBE.  Budget PPF was then temporarily applied to the rear wings to prevent my long gravel driveway from chewing them up, and as indicated by the second photo of the passenger seat, that was a good idea.  The Avons like to throw up gravel.  
 

 

 

The first proper drive of about 2 miles revealed the map is much farther out than the 3 starter maps I've received over the years from Emerald.  With light throttle, shift points around 3000 rpm, and speeds limited to 25-30 mph, the mixture was swinging between too rich and too lean.  Digging into the logs and more drives totaling another 10 miles revealed both a map issue and a hardware problem.  Whenever the accelerator was depressed even a very small amount, the mixture suddenly went lean, then quickly recovered.  I'm assuming this is an acceleration enrichment setting that requires tweaking.  One for SBD.

 

The other issue took some troubleshooting.  Initially there were very random and unexplained full lean spikes (1.22 lambda) lasting a fraction of a second and visible in the logs.  On Sunday morning, after covering just 2 miles in cool temperatures, a spike was long enough that the engine stalled.  Fortunately, it easily restarted.  This stall-then-restart procedure happened about 7 or 8 more times on the 2 mile trip home, then several more times during subsequent driveway testing, including when the car was stationary.  The cause?  The fuel pump was cutting out.  As a safety measure, the MBE cuts power to the pump when the engine stops.  That was my initial guess as to the problem.  However, multi meter testing showed 12v to the pump with the engine running, then remaining at 12v when the engine would go full lean and start to die, then 0v after it stalled and the MBE cut power.  I hope to pull the pump tonight then return it to Deatschwerks tomorrow for further testing.  

 

Other weirdness, albeit minor, concerns the CAN output from the MBE to AiM.  Although all the readings in AiM have faithfully followed what was showing in Easimap, load site was different.  The extremes weren't too far out, with the readings in Easimap ranging from 0-14.8 vs. 1.1-14.3 on the AiM.  But in the middle, things were way off.  A reading of 5 in Easimap was just 2 on the AiM and a reading of 10 was just 5.  As a test, TPS voltage was swapped for load site, and to my surprise the readings were once again perfectly in sync.  Given the load site is a calculation based on the TPS voltage this is a little odd.  Hopefully it's an easy fix with a setting.

 

-John

[sf4018]

Is the fuel pump control module still part of your system?

https://caterhamparts.co.uk/pumps-senders/5336-fuel-pump-module-seven-485.html?search_query=Fuel+pump+control+module&results=184

if I remember right the fuel system has a pressure regulated return to tank from the rail?