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Can you give some detail on the new relay - what type of relay and where you installed it? I need to do the same thing and control the pump run command from the ECU. For me SBD had a 420 race setup but it was quite far off in the end. He spent 3 hours tuning the cold start, warm start, low rpm stuff in one session at the house then another 3 hour session for the full mapping and tuning on a dyno. Very expensive. But haven’t had any issues since.

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?

Any luck?

Caterham's factory installed fire system is based on this system... Lifeline Zero 2000 2.25 ltr Club Fire Marshal Mechanical System (lifeline-fire.com) ...it says it's a foam system, but I couldn't find any more detail on what kind of foam, maybe that's proprietary, dunno.

I have the 9A4. Attached is the Race Studio 3 .xc1 file and the pinout for the ECU if you want to hook the temp sensor up to some spare IO. The CAN output from the ECU is programmable so it is possible to add any sensor to it. MBE9A4-PinoutIssue_F.pdf Caterham_420R New ECU_@20210824_224149_008622.xc1 Cheers, Simon

It's an 8 bit unsigned integer, 0 (0v) = -30C, 256 (5v) = 130C. If you have the SBD ECU have a CAN protocol for Aim RS3 if you want it (I think I modified it some on the ECU side but it's a reference at least).

My wife has that weekend pencilled in for a trip to the smoky mountains, which is about half way there so if I can sort out timing and logistics it may work out.

Did you get to try them out? We had too much rain to cycle through the compounds last weekend, but did try out the A24s - they basically melted during a sprint race, it was a sunny day tho so I guess the track was quite toasty.

Doing it right now, I hate the diff!

Sadly true, the ESG movement in the UK is ruining the potential business climate. Jeremy's Farm highlights this too.

Signed up for Sunday only too. 3 Sunday spots remain, 19 Sat/Sun spots.

Thanks @jimmylukeii, sorry I dropped the ball on this, it looks like the registration opened last week sometime. The novice green group has sold out already unfortunately, but there are 20 spots open in the solo groups. The solo groups will require a list of previous track experience. There is a waitlist possible for the green group though. I didn’t realize it was going to be this competitive , this may scupper the whole event. There’s another series I’m racing in here at Barber next month, it sold out in 27 seconds. We know this because we hit the submit button a few seconds too late. Luckily we got in on the waitlist, but still, it’s nuts right now the demand.

I heard Avon will be shutting down production the end of this year and the molds may move to the US (Goodyear). Don’t know how much of that is true.

Roger Kraus Racing has some ZZR 333 and A24 compounds that just came in if anyone wants some.

I have a set ready for the Mitty in April (along with A64s and A24s). I would hope the grip will be better, but the main interest for me is how many laps will they take to get going. 6 laps on the A64 is too long, about 2/3 of a sprint race.

These are the prerequisites for the pump to run: 1. Master switch on 2. Key in position 2. 3. Immobilizer unit sees the fob 4. Inertia switch ok. At that point the pump control unit is powered up. The unit runs the pump when: - Initial power up it runs for 1 second to charge the system. - Sends a pulse to the pump on each rising edge signal received from the ECU output. It does not stay on if the ECU output stays on . So I modified the pump control relay harness to take out the unit completely and run the power and ground from the clear/white connector directly to the pump (the large green/yellow and black wires). The issue with this is the pump runs even when the engine is not, which is a battery drain issue and somewhat of a safety issue (e.g. if the fuel line breaks it'll keep pouring gas instead of cutting out). I guess a solution could be to find an alternate unit to the H8QTB so it just runs when commanded by the ECU Engine Running signal. May not exist, dunno, documentation is scarce.

Really well thought out and executed, looks great, congrats! When I did redid the fuel system I was expecting the pump control relay to the left of the tank to be a dumb relay that switched on when the ECU command is on. Unfortunately for me it only pulses the pump on the rising edge from the ECU, it's basically looking for the engine rpm pulses to drive the pump. I ended up taking the relay out so the pump runs full time, but it's not particularly safe to do this if the engine is not running to have it pumping gas plus the battery drains really quickly. Looking forward to see what you come up with for this, I'll probably copy whatever your solution is.

Thanks for the responses, registration will open mid February I believe so I’ll circle back early February to gauge interest.

There's been some chatter about having a get together in the Southeast for a while now, so here's the first go to try and organize something. Chin Track Days will be running a HPDE at Barber Motorsports Park on April 15-16, 2023. Chin runs their HPDEs very well and have both beginner groups with instructors and solo run groups, so there's something for everyone. Weather is usually really nice can be unstable this time of year but even if it does rain it dries out pretty quickly. This will be a casual event. The 16-turn 2.3 mile course is finished to a very high level: fantastic surface conditions, and safe run-off areas. Perfect for Sevens. And, the lap is famously surrounded by an eclectic collection of outdoor art installations and sculptures! It's a technically challenging course that rewards car set-up and driver skill over horsepower, and several notable blind elevation changing corners. Right next to the track is the Barber Vintage Museum, one of the world's most renowned collections of motorcycles. The intent right now would be to integrate with Chin's usual group formats. Green: This is a novice group with instructors and classes. Blue: This is the intermediate solo with point-bys. Red: This is the advanced solo group, with no point by. I think we would probably split into 2 groups - the green and blue, any red drivers (if they want to drive with the group) would request a move to blue, but we'll figure this out between the drivers and Chin later on. Maybe there will be more red than blue, who knows. Saturday evening we'll setup dinner at one of the great BBQ places nearby and also possibly one of the awesome microbreweries in town like Cahaba Brewery. Registration doesn't open for a while, but when it does it sells out quite quickly, especially the green group, so if we do want to do this we'll need to be ready. Anyways, I'm open to changes in dates or even locations, just wanted to get the ball rolling!

You have more patience than I did trying to get the OEM supply hose off the tank, congrats. I wish I had your knowledge level when I replaced my fuel system! I would say if you're going to run a return line to the rail you might as well replace the original supply line too, it's a crappy semi hard plastic, the diameter is quite small too and hard to work with. You can then put on your own fittings on the ends. I ended up with 5/16" stainless braided hose with connector... Dorman 800-081 Dorman Fuel Line Connectors | Summit Racing Spectre Performance SPE-29310 Spectre Performance SSteel-Flex Fuel Lines | Summit Racing

They are Hoosier F2000 slicks, the old softer R35 compound (got them on the cheap as the series has moved to R55).

No supply chain issues next year Includes 1 set each of ZZR A64, A24, MAX for the Mitty next spring.

We managed to take apart the u bolts in the tunnel. There was no grease in the universal joint, completely dry. There’s also no zerk or any way to grease it. We IDed the universal joint as a moog 340. We’re going to get a moog 341 with the zerk. I can only assume the shaft was assembled incorrectly by the supplier to Caterham.

One of the U joints on the driveshaft is very stiff. Here’s a theory about the gearbox oil loss: the drivetrain vibration at high speeds is caused by the bad u joint, the vibration from this causes the yoke to vibrate inside the gearbox, which encourages oil flow out past the yoke. Does this sound plausible?

There was a small amount of slip yoke left, maybe 1/2”, the diff is fixed and the gearbox will have I guess a small amount of movement but I can’t imagine it would move that much, so I think it’s fine. The driveshaft can only be removed as is going backwards unfortunately. A local racer is bringing over something called a u joint puller to see if the joints can be serviced in the tunnel. Not familiar with that tool but he seems to think so.