slipstream444

WARNING! This DIY will make your car less idiot proof (and potentially dangerous), especially if you let someone else drive your car who doesn't pay attention to detail... or if you have kids that may have access to your car keys and want to press that fancy candy like red button (the button that would otherwise be overrided by the clutch interlock switch). Do this at your own risk and understand you're removing a safety feature from your car.

With that out of the way... this DIY is relatively simple - you only need to be a little flexible.

First: the picture out of the 2000-2003 S2000 Service Manual - Page 12-4:



Tools: your meat hooks, a flash light, a short (~1"-1.5" long) piece of wire (16 gauge works fine - recommend tinning the ends with a soldering iron if you use stranded wire, but not necessary), and a chiropractor.

Why you would want to do this:
it reduces wear on the thrust bearings/washers during start up that can ultimately lead to crank walk - especially if you have a higher sprung pressure plate such as the ACT setup. If you switch your car off frequently at lights to save gas - this will greatly reduce start-up wear caused by thrust loads created by otherwise needing to push the clutch in to start your car.

To begin - lay on your back staring up under your dash - in the area of the clutch pedal - and the Clutch Position Switch ("B" in the diagram) should be readily visible. This switch releases the cruise control when you push in your clutch. The Clutch Interlock Switch is above the Clutch Position Switch (a little harder to see).
It makes it easier to reach the Clutch Interlock Switch connector if you disconnect the connector to the Clutch Position Switch.
Next - unplug the Clutch Interlock Switch connector ("I" in the diagram),
Then create a small "U" shaped jumper with your piece of wire and jump the two terminals in the connector.
It's a good idea to tape the connector with electrical tape to ensure the wire doesn't come out (your car won't start if it does).
Make sure you reconnect the Clutch Position Switch connector (B) - and then you

03AP1

Nice writeup.

slipstream444

Many thanks.

damuho

If the shifter is placed in neutral prior to starting, will there still be an issue with thrust loads?

slipstream444

The issue is not whether the transmission is in gear or not - it's the force produced when the clutch pedal is pushed in - the thrust force produced by the pressure plate.

damuho

Thanks for the explanation.

I think what I didn't understand (or know) is what exactly is happening when starting the car. I can only think of the load on the diaphragm spring when the clutch is depressed but apparently, there is more.

Is this mod more suitable for those with "upgraded" clutch systems or flywheels?

slipstream444

Absolutely. I have a Comptech FW, ACT PP, and OEM disc. It's more important with higher sprung PPs like the ACT. Ultimately it will save a lot of wear over time no matter what PP you're running.

RedY2KS2k

Maybe, maybe not. I typically shift gears 50 to 100 times for every time I start my car. So saving something like 2% of the wear on the thrust washers doesn't exactly rock my world. Your results may vary.

99SH

Increase life in stop/go traffic? You do realize you would have to disengage the clutch to shift to 1st gear right? Unless you keep the car in neutral you're not gaining anything.

Same thing with the startup issue. Everything you say is valid if you never shift out of neutral.

slipstream444

Most of the wear your bearings see are when there is zero to minimal oil pressure and maximum load - which is at startup.
I don't know where your 2% number came from - but engine manufacturers (who actually do the research and produce the data) have determined that closer to 70% of wear occurs at startup.
Do what makes you happy (no one is telling you to do the mod) - I do what makes reasonable sense based on facts and data.

Someone today asked me: why would a car manufacturer create a process that ultimately creates wear (as in why would they install the interlock in the first place)? - I paused for a second and let them think about the question they initially failed to think about before it came out of their mouth - and their answers ultimately were on the mark:
Lawsuits created the interlock - just as lawsuits created the engine kill lever that's on every lawn mower (which in fact was due to idiot frat boys that tried to save some chore time by triming a row of hedges with a lawn mower - blinding one and maiming the other one that didn't let go at the same time as the one that took the branches in the face). It's cheaper to deal with the wear factors than the lawsuits.
Second - auto manufacturers make money by selling parts - not just by selling cars. A part will eventually wear out - and they're more than happy to sell you a new one.