Fuel shut off clarification.

[xxobuick]

Ok, so How I read the rule book, it says you can have a fuel shut off by two methods.


First the pump needs to be on a switched ignition circut, as well as:

Microprocessor controlled

Oil Pressure Switch

Or inertia, is this correct, you only need one of the three?

[geh458]

According to the SCTA2010 rule book (3.I.1  pg31), "All cars with other than stock fuel system shall have a fuel shut-off within the drivers reach".  I suppose this could be the ignition switch, or other toggle switch on the dash.  The third sentence in that section says "All electric fuel pumps shall have an inertial or other positive "shut off switch" e.g. microprocessor controlled , or oil pressure switch". 

So, I think your assumption of two method is correct, at least that's how I interpret it as well.

[jimmy six]

xxo. I'm using the oil pressure method as #2. Seemed the easiest installation. Glad I didn't do it last year and waited for that to be added to the rule book. Engine runs fine with the pump switch in the off position after initial start...Good Luck 

[Ro Yale]

I've built several of these fuel inertia switches. I have 2 left if anybody needs one. They have a rubber sealed toggle in them and are stainless steel internals. So are corrosion resistant. I'll be out of touch til next tuesday but available after that. I can email pics if you need them.

[Clay Pitkin]

So is there a specific location that it has to be mounted? ie: engine compartment, inside the car,??

Please advise

TIA
Clay

[38flattie]

I've built several of these fuel inertia switches. I have 2 left if anybody needs one. They have a rubber sealed toggle in them and are stainless steel internals. So are corrosion resistant. I'll be out of touch til next tuesday but available after that. I can email pics if you need them.

I need one!

[4-barrel Mike]

A nice (unused) Ford switch is about $2.25 locally at the local pick-and-pull.

Mike

[RichFox]

Since we are way to high class around here to have a junk yard or even an Auto recyceler I bought new from Ford. They don't cost much. Get the pig tail. It has a wierd plug in.

[38flattie]

Well, that's easy! I'm not familiar with them, but I'll do a Google, and pick one up. Thanks!

[thundersalt]

About $15 new from a Ford dealer

[4-barrel Mike]

The initial discussion: http://www.landracing.com/forum/index.php/topic,5080.0.html

Mike

[panic]

Just an aside: any chassis with a fuel accumulator between the pump and the engine also needs a solenoid between the accum and throttle to block fuel release.

Curious: what's the safety for a Hillborn pump drawing from a pressurized holding tank?

[jimmy six]

No matter what you do if you are using a carburator, the bowl needs to empty prior to the engine shutting off if the ignition source is not turned off. There are many ways of doing this and the SCTA has only directed the electric pump to be shut down due to an accident or if you use an oil pump switch a catastrophic engine failure. I'm glad the SCTA has given us options however I hope that they stay with where they are now and not continue to add more and more devices.

For the most part these enertia switches were not common until the the use of electronic fuel injection of which 100% of the motoring public now has.  Electric fuel pumps need to shut of in case of engine failure or accident but each device you add becomes another thing to fail. With electronic FI the stopping of the high pump normally stops the engine and in an accident the pump will not continue to "fuel the fire". Same for a low pressure system the 7+ pressure pump is made to turn off under our rules.

I have known competitors to use Hilborn mechanical pumps with carburators and they all have mechanical shut off devices between the pump and carb some between the tank and the pump. Perhaps there should be an electrical device here also operated by the either of the 2 allowable SCTA approved ways of shutting off fuel. The only drawback to this is the additional return line to the tank if the engine does not quit running during the accident or engine failure.........More to think about when you run this type of system.

I don't think rules should dictate everthing a competitor does. You should think about protecting your driver without being direted by any rule.

[Avanti Kid]

Keeping with the rules we installed a system to provide the protection SCTA desires, our system has a 40psi oil pressure switch that in an "Auto" mode if it sees 40 psi or lower it will energize a relay and its contacts will open the circuit to the electric fuel pump and also open the circuit to the engine's ignition system. We decided if our engine's oil pressure gets that low we don't want to depend on the driver to turn off the fuel pump and ignition.  When we first start the engine we place the Auto/Manual switch to "Manual" position, then after the engine starts, we switch to the "Auto"  mode position.  Also if needed the driver can turn the electric fuel pump off my its own switch on the instrument panel.  We feel with this system it provides more protection to the race engine at low oil pressure conditions.  Its not that hard to design and install this concept.  Dave

[Milwaukee Midget]

Picture of a typical Ford unit - this one out of an Escort, installed in the Midget.  Two bolts attaches it - paid $20 at a bone yard for it, and it included the pigtail.