Haynes Forums - Chris's new build of an MX5 based car

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Ha ha, I thought you'd like that one :p

I love how they sneak these little snippets into the manual where you'd least expect them :D

So all the car has too comp to exterior 100mm ball test and requirements. No 165mm ball test at all.

If any pedestrian I knock over finds his knee under my side of the dash then I doubt he'll be particularly concerned about his friggin knee! I'll be bloody concerned because he'll be sitting in my bloody lap! If his heads down then there then that's really worrying!:eek:

This ball is becoming quite a problem for me.

Not anymore...

Not my best work but who's going to see it down there. And if the MAN wants to wave his balls around my undercarriage he's going to be disappointed. Obviously I have to do a bit more finishing off. This job is NOT my favourite bit!

Arrived this morning.....

So my vehicle should follow the flow diagram path, yes, yes, no. Assuming it fails the BET test, which is likely.

Any haynes built using an engine from a vehicle manufactured during 1995, before or after July 1995, will have an Engine manufacture 'Effective Date" of 1st January 1995 if you can prove the engines date of manufacture as the letter above does. Useful to know for other builders as older mx5 cars get rarer, which will probably happen soon I think the way the sills rust through.

I've kind of got carried away after having to replace the garage door. I'm now replacing the rotten window and have already rewired the garage, fitted an alarm and it's now brighter than the sun in there when you turn on the lights. Oh and a tool board with shelving. I thought I'd make the garage more usable now I've nearly finished building this car! :rolleyes:

Piccy. Someone gave me some MDF and it was taking up space in the garage making it smaller so I reversed it into making the garage bigger! Needs more tool hangers (small screws) .

So I'm in the process of attaching lots of little bits of rubber and plastic to my car in a most unenthusiastic way. Not enjoying this bit at all.

Decided to do a compression test on the engine. Probably out of pure boredom but it's good to know where you stand with an engine before you put it back on the road after 5+ years without any regular miles.

Happy with that. Couldn't get my head round the high numbers as 9.0 CR x 14.7 is around 130 odd psi

bit of digging.....

Quote:

Compression Tests

1.6 Miata has a compression ratio of 9.4 to 1. So 14.7 psi times 9.4 equals 138 psi. But the Shop Manual lists 192 psi due to heat raise from dynamic compression. Cam timing also affects the pressure reached on the gauge. The longer duration the cam, the less the pressure.

From 1992 Mazda workshop manual (1.6L).
Compression ratio: 9.4:1 (manual), 9.0:1 (auto).
Compression pressure for both;
Standard; 192 psi,
Minimum; 135 psi,
Maximum difference between each cylinder; 28 psi.

From 1995 Mazda workshop manual (1.8L)
Compression ratio; 9.0:1 (manual and auto)
Compression pressure;
Standard; 182 psi,
Minimum; 128 psi,
Maximum difference between each cylinder; 28 psi.

in Mk2 1.8 209 is standard, 146 is minimum, max difference between cylinders 28 PSI.

Explains a lot....

In other news I've spoken to the new wizkid at work and he things this is doable..

Quote:

Originally Posted by alga (Post 97571)

Lukasz, here's the schematic:

You can use Arduino Uno or whatever to test, but then to embed something smaller like Nano or Pro Mini is more convenient.

If you look at the source, https://github.com/alga/shiftlight/b...shiftlight.ino , you'll see that the pin numbers of the input and outputs, as well as RPMs for each led and for the blinking warning are spelled out in the constant definitions.

In order to set the switchover RPMs on a button press you'll need to add a button that grounds one of the free input pins, set the mode for that pin to INPUT_PULLUP, and in the loop check if the pin is LOW, and if it is, fill in the thresholds array with the new values based on current RPM. You'll need to delete the const specifier from the variable definition in order to be able to modify the array. Piece of cake.

So I have someone to hold my hand if/when I have a go at this. I did, rather impulsively buy this at the weekend and hooked it up tonight. Works well. Instructions for setting it up are a bit rubbish but it's straight forward really. If I can make my own I'd use that instead and integrate it into the dash somehow.