Entry into motorsport

[albanycobra]

Your oil pressure switch idea will get you hurt and here's why....your Accusump will maintain oil pressure till it's fully expelled so meaning after you have rolled over and your unconscious for a period the fuel pumps are going to pump till the accusump drains.....if you had an inertia switch in the system the second your car had a decent impact or rollover the system is turned off for you......

[Modena]

sounds like the idea would be a manual kill switch with an inertia switch and an oil pressure input and a partridge in a pear tree

[spookypt]

Nope sorry Dave again I disagree. It wont. My engine is dry sumped and the accusump is used to prelube on start not maintain oil pressure like conventional engine oil pump configurations. It's manually operated by ball valve and plays zero part in maintaining oil pressure.

My comment to Modena about his set up was that if he was relying on his kill switch to fuel pump relay being enough to stop him instantly in a jammed wot event it won't be instant enough.

[Modena]

originally I wired that in actually for convenience because I wanted to be able to turn on the ignition without the very noisy pumps running, for wiring troubleshooting and gauge configuration etc, it sort of then doubled for safety, but point taken I will wire in ignition also.

cheers

[spookypt]

Modena don't get me wrong it's a good idea for anti theft. Had a truck wired to dead switch to pump and it got stolen and I found it a block away.

But in the event that u get a throttle jam and u happened to have an auto u can't clutch to stop so killing the engine dead fast is paramount and your only way to stop before u hit something.

Just thoughts to help that's all.

[albanycobra]

Like you said, set your car up how you like ,but I'll take an inertia fuel pump switch cut off over an oil pressure cut off any day.

[spookypt]

Dave if you relying solely on that alone then sure but in my case my car is set up with kill switch to ignition, fuel pump kill switch, battery isolation that kills everything and fuel pump cut off on no oil pressure.

All set up with the help of Stokel Motorsport and Ozvenom so I'm pretty confident in its configuration.

The first part of my comment was regarding instant kill as I've mentioned so you can forget an inertia switch saving u from much before u hit it.

Moving on.....

[albanycobra]

No not moving on Mate...oil pressure switches to kill fuel pumps is bad advice.

[albanycobra]

If your engine is EFI then the oil pressure switch is moot anyways as when the engine cuts out (no oil pressure) the Ecu detects no crank rotation and will turn the pump off....

[spookypt]

Ok cool let's continue. My car is carb'd so perhaps an oversight on my part thinking modenas was as well with my suggestion given. I still stand by my suggestion of a direct kill to ignition if nothing else. Based on events past this set up is a no brainer for anyone who's had a stuck wide open throttle.

That said, as my set up it essentially old style nascar with twin msd etc the Holley Low oil sender cut off switch is what nascar mandated prior to them banning outright all electric fuel pumps and going to mechanical. Good enough rule for them good enough for me too if I'm using electric pump.

Now can we just agree I didn't take into consideration modenas specific set up and you in turn to mine equally so.

[Towmaster]

In a WOT situation you have no time and your automatic reaction is life preservation which means both feet on clutch & brake and steering the car if possible. Unless it's happened to you a couple of times then you are generally not prepared and would not automatically hit a kill switch before something happened. If you do hit something and the engine is still running and maybe you are unconscious then you're in trouble if you don't have an inertia switch. Most modern computers have an inertia switch built into them so a lot of vehicles here are ok in that respect. So if your vehicle runs a factory LS or Ford computer then you should be right, your computer will shut down the engine & fuel pumps upon impact. There is a reason manufacturers build these things into computers. You will then need to reset that switch before it starts again ( I think). Nothing wrong with an extra oil pressure switch to save your engine but you can't be 100% confident that in a split second you will have the ability to hit that kill switch.

Just my 20c worth.

PS thank god I haven't had a WOT situation but have had 2 cars I was driving spear off the track on oil and I probably had 1 or 2 seconds to react and my hands were firmly on the wheel trying to avoid a crash.

[spookypt]

Originally Posted by Towmaster

In a WOT situation you have no time and your automatic reaction is life preservation which means both feet on clutch & brake and steering the car if possible. Unless it's happened to you a couple of times then you are generally not prepared and would not automatically hit a kill switch before something happened. If you do hit something and the engine is still running and maybe you are unconscious then you're in trouble if you don't have an inertia switch. Most modern computers have an inertia switch built into them so a lot of vehicles here are ok in that respect. So if your vehicle runs a factory LS or Ford computer then you should be right, your computer will shut down the engine & fuel pumps upon impact. There is a reason manufacturers build these things into computers. You will then need to reset that switch before it starts again ( I think). Nothing wrong with an extra oil pressure switch to save your engine but you can't be 100% confident that in a split second you will have the ability to hit that kill switch.

Just my 20c worth.

PS thank god I haven't had a WOT situation but have had 2 cars I was driving spear off the track on oil and I probably had 1 or 2 seconds to react and my hands were firmly on the wheel trying to avoid a crash.

According to online GM tech (Believe what you will) and to further add interest... on stock GM ECU's the inertia switch current "bypasses" the relay through the oil pressure switch once the OP switch closes. Once the OP switch closes it becomes the fuel pumps primary source of power and the ECM uses that power going to the fuel pump to monitor the presence of oil pressure. The fuel pump through the ECU was designed to shut down if it loses it's oil pressure. (Ie a crash) Its a brain so it also sends an action for start up to run fuel when no OP exists.

So, if running a carb the oil pressure sensor inline to electric fuel pump is doing the same thing in a generic sense. It senses low pressure and in turn turns off the fuel pump.

Everyone's car is different so don't think generally or think he did or didn't do it so I can or cant. Do your research, get expert advice and be confident in your process.

[dallas_]

Interesting discussion. Seems to be two related but separate functions. My primary concern was the possibility of being upside down and the car on fire. I thought perhaps I would prefer the fuel pump to immediately cut off in that case.

[Towmaster]

Regardless of the argument I wouldn't like to be unconscious in a crashed vehicle that was still running because it still had oil pressure.
I guess, like Matt said, if your serious about it, do your research and only believe about 20% of stuff you read in forums
I guess I was just lucky, for about 5 years I did all my sprints stuff with a motorbike helmet and a basic race suit, gloves and harness that I got off eBay. After a scary moment down Conrod in the Cobra at 250k I decided I was no longer racing the Cobra...... (This paragraph is believable lol)

[spookypt]

Dallas, in the end Dave and I are talking about the same thing, safety. Dave is not aware of the specifics of my car so the general accusump and efi comments didn't apply but in turn my general comments to Modena about his set up where also ill fitting and poorly supplied.

Whether it be carb, efi, manual, auto daily or race car you need to ensure you have all your safety bases covered. What's important is the car needs to be able to essentially cut off its own fuel supply without driver aid.

We are probably getting too picky with the summantics of a particular process. We just need to highlight safety first, be aware and set your car up correctly. In an open car, should it roll there's more chance or you being flung from or breaking limbs if not restrained correctly which includes arm restraints and yet I can count on 1 hand how many open cockpit drivers I've seen wearing them in 10 years of going to the track.

I'll conclude by saying that recent events here have highlighted 2 things.

1. We have a great cobra community here in Oz. We don't always agree, we get the $hits with each other on occasion and we can push the Aussie humour to extremes but when the poo hits the fan everyone comes together and its those friendships and mateships that keep me involved.

2. It highlights just how quickly things can go from fun to phukd and we need to ensure that while what we do is to remain fun, a higher degree of safety and personal awareness of what can happen must apply.

Food for thought.

[spookypt]

Originally Posted by Towmaster

Regardless of the argument I wouldn't like to be unconscious in a crashed vehicle that was still running because it still had oil pressure.
I guess, like Matt said, if your serious about it, do your research and only believe about 20% of stuff you read in forums
I guess I was just lucky, for about 5 years I did all my sprints stuff with a motorbike helmet and a basic race suit, gloves and harness that I got off eBay. After a scary moment down Conrod in the Cobra at 250k I decided I was no longer racing the Cobra...... (This paragraph is believable lol)

The funny (or not so funny) part Ash is that for 5 years you were happy to have your inertia switch installed but if you ended up unconscious in your crashed car you at least had your motorbike helmet, basic race suit, gloves and harness off eBay to save yourself.



Seem a little odd to you?

[albanycobra]

I agree the discussion is to achieve the safest outcome. If one person makes a change to improve their safety then it's been worth it.

If you are in WOT stuck situation I believe the best course of action is clutch in straight away. Get on the brakes at the same time and bring the car into control then switch off, let the motor blow ,better than a big crash.

[Towmaster]

Originally Posted by spookypt

The funny (or not so funny) part Ash is that for 5 years you were happy to have your inertia switch installed but if you ended up unconscious in your crashed car you at least had your motorbike helmet, basic race suit, gloves and harness off eBay to save yourself.



Seem a little odd to you?

If i ended up upside down in my car then I would be dead..... or severely paralysed. No substantial rollover protection.
I guess we make decisions and take chances..... I used to shoot roos (vermin eradication) from helicopters on school holidays with my father and uncle...... You could say I have tried to reduce my risk a little these days....

[spookypt]

And for those who don't run a manual box think what you would do in the event this happens without the clutch option. Split 2nd timing. Be prepared, think about what we do and the consequences.

I had a WOT stuck at a Paul Morris Track day at his training centre in a Lotus Exige with a driver trainer on board. Before the trainer knew we were around the corner safely but it was a clutch in on the brake moment that happened in a millisecond, I was heading for the canteen and never thought about turning off the key. You just don't think that fast enough. My kill switch is as close as it can be on my race car and I hope should the event occur its a matter of a swipe and Im off.

If nothing else as you save Dave the robust banter may have prompted some minds from thoughts to action so if that has prompted increased safety compliance that's a good/great result for all.

[spookypt]

Ash, good for you I say for increasing your safety awareness and making a change to continue your enjoyment in motorsport. Its great to see that you take it much more seriously now.

Roll over protection in our cars is another huge safety perimeter that should be considered by people thinking about tracking their cars. A chrome shiney bar with no structural rigidity and a windscreen wont do much at all.

Despite my funny car style 086 moly cage in my race car I have a hard top on the way and will build a compliant cage to make me safer.