What have I done? Two N00bs Try to Resurrect a 7

[YourEconProf]

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. 

[MV8]

Does it know the percentage of ethanol or is it just a switch to indicate ethanol is circulating in the fuel lines?

[YourEconProf]

6 minutes ago, MV8 said:

Does it know the percentage of ethanol or is it just a switch to indicate ethanol is circulating in the fuel lines?

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!

[YourEconProf]

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.

 

[Vovchandr]

12 minutes ago, YourEconProf said:

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.

 

 

That location on the dash is typically for a foglight but the icon is not something I've ever seen before.

 

Looking like a brake pedal I can only assume it's a brake fluid switch test which is something regular cars have but in different place with different icon. 

[YourEconProf]

28 minutes ago, Vovchandr said:

 

Looking like a brake pedal I can only assume it's a brake fluid switch test which is something regular cars have but in different place with different icon. 

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

[sltous]

Some details from a classic mini forum: https://www.theminiforum.co.uk/forums/topic/117159-brake-test-switch/

[YourEconProf]

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?

 

[toldfield]

On my car, '82 S-3, 

 

Green is the turn signal indicator

Red is generator 

Blue is high beams

[NSXguy]

i shared an assembly (disassembly) manual for an early 7 in the file archives section. It'll be helpful with your chassis/ wiring efforts. 

 

Edit:

here is the link

 

Edited April 10 by NSXguy

[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. 

 

 

[MV8]

That looks like some custom bits added to a euro industrial starter S114-252A. I suggest buying this one (while it is still available) and changing the pieces on the end or worst case, swapping the motor. Can't beat the price.

 

Starters cannot dissipate heat well. To save you from another replacement, consider a duty cycle of 45 seconds of cool down for every 5 seconds of engagement.

 

https://www.ebay.com/itm/135598781885