Pokey

I don't recall the difference off the top of my head, but do recall that the diameter difference between the 13" and 15" option as being small since the 13" uses a taller tire sidewall.

Maybe (likely) disappearing from the new car market, but I believe the collector and competitive enthusiasts will be able to buy petrol for some time to come. There is a car show here in the Seattle area in June that usually has a few hundred cars and trucks of all kinds covering multiple city blocks. Every year there is a handful of battery converted cars and trucks from back when doing so would have been truly novel. Maybe after I'm long gone that show will feature electric vehicles with a handful of oddball petrol samples. Heck, maybe the future will have someone converting an electric to petrol as a retro creative outlet.

My Caterham and I have our first opportunity to spend some time on a track, and I'm wondering how important it is to swap the windscreen with an aeroscreen? I'll trailer the car to the track, and have a full-face helmet and an aeroscreen, but for the occasional track use I'm wondering when/if it makes sense to do the swap given the vast majority of time the windscreen is needed for the street. I'm assuming the primary reason to take the windscreen off is to protect it from destruction, and secondarily having a flat pane of glass at a right angle to the direction of movement might negatively effect what little bit of aerodynamics we have in a Seven?

I did for grins, using a very small edge trim around the entire perimeter of both the upper and lower openings. Totally not needed, not often done from what I can tell, but it was COVID and I was looking for anything to make the build take longer.

Congrats!

I've got a question about the idle situation borne of both ignorance and curiosity. When the IAC is doing its thing, is it bypassing or operating the butterflies? I'm wondering if the butterflies are moving during the runaway revs...

Maybe I'm just saying the obvious, but the reply indicates they think Caterham is importing vehicles - they are importing kits not cars. It sounds to me like the kit part of the equation has been left out.

My assumption would be the ECU is unlocked, but the mention of the mapping kit only seems to refer to diagnosis rather than changes. I would just be doubly sure that what they send is something you can have someone local to you tune.

I'm trying to remember, but isn't the sender in the submarine for the gauge and a second sender for the ECU? I'm thinking the second sender is down on the left hand side of the block where the plumbing connects. Or maybe I'm just imagining all of this. For those of us with a dry sump, the oil temperature sender is in the bottom of the sump tank. My wiring harness doesn't have what is necessary to connect to it though, presumably because Caterham assumed I'll be pulling wire to connect direct to a gauge.

If you are concerned you can always add your own bump stops.

I have a rough analog that occurred with my build. The transmission kisses a frame member ever so slightly on one side of the tunnel. I tried repositioning using different methods and even pulled the engine and started all over but in the end the transmission is a hair-width from touching at most. I was concerned that movement would cause contact which would cause vibration, but in the end whatever vibration that might be transmitted is minor. Sure seemed like an issue at the time, but in the real world it proved otherwise. Interestingly enough, Bruce at Beachman Racing built a 420 a few months later and encountered the same situation, so when Caterham says "not uncommon" that is probably Caterham-speak for, "we made it that way."

Love the meatballs! Where did you get them?

Got it. In my mind's eye I was thinking you could shorten the forward arm without lengthening the rear arm and that would shift the axle forward and up.

@KnifeySpoony, just asking because it is something I might have done and we are spitballing, but did you use the upper or lower radius arm mount point on the chassis? If there is an issue here it may not be with the DeDeon being too low but too far back, and I'm not sure if Caterham uses the same radius arm for the S and R. I don't have the Watts. Does it have forward/aft adjustability such that you can move the DeDeon forward to create clearance?

@KnifeySpoony, just asking because it is something I might have done and we are spitballing, but did you use the upper or lower radius arm mount point on the chassis? If there is an issue here it may not be with the DeDeon being too low but too far back, and I'm not sure if Caterham uses the same radius arm for the S and R.

I can do like sf4018 and jack up the rear to see what clearances look like now, but otherwise I'm not going to be much help. I assembled the rear suspension with the DeDeon supported, leaving roughly a one inch gap in the area where I think KnifeySpoony has contact. @KnifeySpoony, suggest adding a photo or two loaded and unloaded so those of us with the same or similar car can compare.

And herein lies why I think spraying methanol/water is a better option. You need only a single tune as the ratio is fixed, and you get all of the cooling benefits, perhaps even more so. BTW, anyone want to buy some bottles of methanol mix?

I had the exact same experience with my 420R. For grins I read the actual temp from the ECU rather than the gauge and found the gauge was reporting back about 5C higher. They still run hot, presumably for emissions, but it wasn't quite as extreme as I thought.

My wife might see thru that ruse if I were to return with a trailer that happened to have a car on it, but as a strategy I think it is brilliant.

Sorry, forgot to mention that the cost for methanol isn't too steep, a few hundred for a kit was my one experience. I think the tune cost more. As for E85, I'm not aware of a cost, but it will require a tune too and coming up with a baseline for pump E85 will be harder than for a consistent mix of methanol and water. And that is the extent of my knowledge, so let the correcting begin!

I'm looking forward to the responses on this one as it sounds interesting! But having said that, my gut feeling is temperatures for the purposes you mention may not be much of an issue. But if I'm wrong, then I might consider spraying methanol instead.

Thanks for documenting this Brightonuk. Last summer I was shopping for a tilt trailer but never pulled the trigger as I wasn't able to confirm what would work (approach angle and weight distribution).

Very nice! Sorry to pepper with questions, but your answer does beg the question as to the compression ratio? Just wondering if a little racier fuel wouldn't bring out a fair bit more power (not that it is needed, of course).

@John B, sorry if you already mentioned, but what fuel was used to get those numbers?