Who is using some type of automatic fuel pump shut off in case of a crash? I've heard of oil pressure switch and impact sensor. For the oil pressure switch to work, the engine has to die, that might not always happen soon enuff. An impact type could potentially cry wolf on a hard launch in the final round after you've clawed you way thru a 132 car field.

So who uses what, how is it working out?

Thanks,
Joel

How about a Ford starter relay at the positive battery terminal, with a very large mushroom head switch next to the shifter to control it? In a panic situation just slap the button and shut the whole electrical system down. You could also leave the safety switch on so you don't have to unbuckle if you forget!

The easy to get at master switch is a great thing, but what if you get beaned and go unconscious or pass out from medical reasons or something? I think that's where an automatic system comes into play.

Sounds like your looking for a dead man switch like the Railroads use

This is what i use on mine and my customers

https://www.ebay.com.au/itm/2746478...Stfqw8AIVEayWCh2VvQbKEAQYBSABEgK78PD_BwE

Its a tachometric relay . Ignition on no run 3-5 seconds of power to pump . So you can prime if fuel empty etc . Will shut off when no tacho signal .
Very reliable , but if it fails easily bypassed

Tex

My EFI will only run the fuel pump when it has crank signal. The problem is EFI can run upside down I imagine so the engine is probably less likely to die unless it takes a direct impact to the crank sensor. Hmmm

I found this comtroller on amazon, price doesn’t seem bad.. https://smile.amazon.com/Revolution...itch+cp30&qid=1620165617&sr=8-13

I do like the idea of the ford stater relay.

I have the ford style steel ball electrical cutoff on my cars. I road race. I have set mine off at a inappropriate time, like on off course spin, that then strands the car with approaching traffic. The easy fix was to relocate it so from the drivers seat i could reset it, and get underway. I don't see how a "hard launch" could set it off, unless the gyrations got rather extreme. It seems to need a hard impact, and I'm keeping mine as is.I think they are smart. The street cars get one easy to "kick' as I'm exiting in a potential car jacking(?), leaving the car running long enough to get some distance between me and the gun toting thug driving away.

I use an oil pressure switch, but also added two bypass switches. One to prime the system, the other to disable it for anti-theft. I also have a nitrous type trigger switch on my outboard carbs to kick the pump up to high speed when they are opened. I run a Fuel Labs 2 speed pump.

Of course the switches including the oil pressure switch only interrupt the low amp side of the relays, or the trigger voltage. I use 2 40 amp Bosch relays to feed the fuel pump.

what kind of sensors do factory auto-shutdown systems use ?
i realize they run through the PCM, but they use some kind of sensors don't they ?
if so, would it be possible to utilize or modify a couple of factory sensors ?

Most of today's car utilize Air Bag modules with a mix of internal and external sensors, when they detect an impact they send a Fuel Pump cut-off signal through a Bus line to the Engine or Fuel pump module.

I use oil pressure switch to ground the relay.

The switch is the same one Mr Gasket used to sell, it is sourced from a 1974 Chevrolet Vega.
There is a matching plug/connector available for it from the same application.

It's not a perfect solution, but at least gives one layer of protection compared to full manual.

Story about the Vega oil pressure switch. Years ago living in the Seattle area I was looking for a project and kept noticing a really nice Orange Vega GT wagon on the back side of the Ford used car lot. After noticing it hadn't moved in a few weeks I dropped by and spoke to one of the salesmen. He finally admitted that they would sell it at a give-away price because they couldn't get it started. After settling on a great price I asked him if he would throw in a couple quarts of oil which he did. I poured the oil in the engine and it cranked right up. He was amazed and was really ticked because their mechanics didn't know that. That nice little car became my 350/turbo 350 daily driver. Loved that thing!!

that vega story reminded me about the vega my brother owned when he was in high school.
he always carried around a 5 gallon jug of oil in that thing because it used so much oil, and acted the same way when it was down a few quarts.

Yep, Vega's had a three terminal oil pressure switch, and one of the terminals grounded the electric fuel pump. If you didn't have oil pressure, you had a fuel pump that didn't work, so no fuel to the carb. My Vega never let me down, but I did carry a shovel in back cause they could get hung up in snow drifts. In 1974, I sold my daily driver for more than I was asking due to the gas shortage. I never had a gas shortage, cause where I worked we sold Stoddard solvent, which burned just fine when mixed half and half with gasoline, and was even cheaper than gas at the time.