YourEconProf

It's been a long time between updates; my life got busy, my youngest child got married, my buddy got a girlfriend, and I got stumped by a bad crank sensor. The engine harness is done, though we haven't sealed it up. I made a few mistakes in laying it out and had to run some additional wires externally, plus the Megasquirt seems to be much happier when the signal wire shielding is grounded straight to the battery. Once we are idling, we'll re-loom it all. One of the original injectors (Holley 42lb yellow tops) was stuck open. Annoying, but they are supposed to kind of suck anyway. So I upgraded to genuine Bosch Green Giants (440cc, only 160 for 4 at ECS Tuning!). I replaced the fuel pump & filter; the system is still not holding pressure great after the key is off, but I think that's because of the old pressure regulator. I'll worry about that later. I installed a Hall sensor for the crank, and while the ZX2 didn't have a crank sensor, the black top Zetec is set up for one (head is drilled and the intake cam has a timing tooth) and so I can run sequential fuel with the ITBS. I spent quite a bit of time figuring out why I was getting such noisy crank signals, redoing lots of the harness to clean up grounds before realizing that the sensor itself was bad. Once I replaced that, everything cleaned up. While I didn't find any actual tunes for the Blacktop Zetec, I did find some tables to start with, though pretty much all the settings needed to be sussed out, particularly the setup for the crank sensor. In fact, while sweeping settings to find the base timing (homemade trigger wheel, so no built in timing marks on the wheel or the block), I burned out the starter.

So do I understand correctly that this Speedo/SkyDrive combo means that the speedo will work (using GPS speed) regardless of mechanical connection to the drivetrain?

Also, the car has 3 lights between the tach and speedo: green, red, and blue. I'm assuming that blue is brights, what are green and red?

What would a brake fluid switch test do? This car does have brake lights actuated by fluid pressure.

Also, does anyone know what this switch (the one that looks like it has a pedal on it?) does? I'm now turning to the chassis harness, and this one is confounding me.

It knows the percentage, and then in the CPU, you set up tables for pure gasoline (really E10) and E85, and then the spark & fuel are calculated by interpolating between the two tables. I've converted a few Miatas, and its a really nice system, though it means double the work of tuning, which, with ITBs, I'm not excited about!

Some long overdue updates...work continues! We have the engine harness nearly complete; it's the wiring set from Megasquirt for an MS3Pro Mini that has been adapted to the Caterham. The trigger wheel has been a barrier, but hopefully the custom-made wheel will arrive tomorrow and get welded onto a pulley this week. That will permit crank timing with the the DIYAUTOTUNE Hall effect sensor. Likewise, the blacktop Zetec has a one-tooth intake cam and is already drilled and ready for a cam sensor. This will allow setting it up as a fully sequential fuel system. Also, as the motor is 12:1, I'm installing (as I do on all my cars) an ethanol sensor to tune for flex fuel.

Just a reminder, there is a build thread with much more up to date info over the Build Threads subforum. Is it possible to lock this thread to force conversation over there?

Yes, this is what happened, my friend is used to working on domestic hot rods, and saw the visual similarities. It's actually a Torsen diff, though I'm not sure if that's been swapped into the Marina housing, or a different housing.

Too bad you aren't closer. But if you want to try again, LMK. If it starts & idles on the stock ECU, then getting it to run on a MS3Pro PNP should be super straightforward. Then its about getting it tuned so the turbo doesn't ventilate your block... I messaged you my phone number & email. Feel free to reach out if you want to put that on your to-do list.

So so much that I've learned about the car since connecting with the original builder, @super7guy. In short, the car was listed on BaT twice, and those listings provide a tremendous wealth of information: https://bringatrailer.com/listing/1983-caterham-super-7/ https://bringatrailer.com/listing/1983-caterham-7/ The VIN was decoded by @Croc in an earlier thread: Chassis number decode LCS4190VCLM LCS = Long cockpit 4190 = chassis number VC – Vegantune VTA engine L = Can mean LHD or live axle. Both apply here. M = Marina/Ital axle (live axle) I'm the 4th owner, 37 years with @super7guy, 2 years in Oregon, 4 years with previous Ohio owner, then me. Motor dyno'd at 200hp according to sheets in BaT listings. Specs are: Focus era 2000 nitrided crank; good for 8k, better to keep to 7.5K crower rods J&E pistons (12:1) Esslinger head (17xx) with oversize valves cams just ground by schneider to 236 I 232 E (I 6-8 thou, E 8-10 thou); best to check clearances before hard run enlarged steel pan; doubled swing gates. ram 2300 clutch 6 puck sprung disk special steel flywheel from UK with weights removed to get to 12 lbs; top fuel 1/2" ARP bolts to 150 ft-lbs

Hang on...you are running a turbo on a stock ECU?!? Oh...so much more news coming in the next couple of posts about that. :-) Any idea on the dates or sponsoring org?

No worries. I'm putting in a MS3Pro Mini (i.e. Megasquirt family) primarily because it's a pretty common ECU, and it will be my 4th or 5th to install. My current issue is that a previous owner put a different flywheel on the Zetec, thus removing the crank trigger, and replaced it with a custom crank pulley that had an odd 4 point timing setup specific to that ECU, which is no longer made or supported. So I'm trying to kludge together a Focus pulley with a 36-1 timing wheel, as the ones for the 2002 Foci with timing wheel don't align with my accessory belt. Further goal is that since this car has ITBs, that I'll add a cam sensor, so I can run full sequential fueling, but I need to get the crank sensor working first.

Get it running. Get it on track at least once. Dyno it for curiosity, probably not Dyno tuned. I’ve already started the new harness and ECU, as I think it’s the quickest path to getting it running.

@super7guy So. Many. Questions. I'll email you directly. In the meantime, I started a build thread here, and there are high quality pictures in the google photos album below, including the chassis stamp--although I've never been able to locate the Caterham ID. https://photos.app.goo.gl/6qKo4TBgRanR2VUN6