[Land-speed] Inertia Switch Specs...

[drmayf]

James, all... I too wonder how to demonstrate that the device is 
functional. But another thought also comes to mind. Are these things 
directional?  Would they activate in a roll over?  Or does it take the 
10 g crash loading of impact to actually trigger them?  If they are 
directional, then would the demonstration need to be conducted in three 
orthoginal axis and then off axis conditions?  As an old test guy I'd 
say yes.  Each one would need to be activated in all directions or at 
least a good sampling of them.   Anyone know how the SCCA regulates and 
specs this kind of system? Heck, since it is a safety feature, maybe it 
needs an SFI tag as well....Then a manufacturer would be on the hook to 
demonstrate that it works.

mayf

James Tone wrote:

>There is a discussion about this on the Landracing website. It's obvious that at least 2 folks have been using these switches and the rest of us have 1+ years to figure out what to do. 
>
>Holley blues and Mallory 110's do not draw high amperage and only ask for a 7-8 amp fuse. This style of pump could probably be used without a relay. Dan stated on landracing "proof of excecution" and that may be a problem as I don't know of a practical test; maybe Rick does. To me you could mount it on the frame next to the pump and it would do what it needs to do in some kind of an impact. I can't see it activating in a spin but on an enddo it would do it's job. I'm going to "wait and see" before anything but am definately leaning towards the FOMOCO.
>
>  
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>>Subject: Re: [Land-speed] Inertia Switch Specs...
>>
>>First
>>The impact to knock out the "inertia" switch is considerably higher than the 
>>bumping of a push truck.
>>How many push trucks have triggered this switch?
>>Have anyone with anything manufactured in the past 16 or so years 
>>experienced this other than in an accident?
>>Quit worrying.  Mount it like the OEM did, and make sure it is accessible to 
>>you.
>>Hell, mine in the liner is under the seat, and the seat shell has to come 
>>out to reset it.  Thats how much confidence I have that it is not 
>>accidentally going to be tripped.
>>SCTA is not going to tell us what to use but will look in inspection for the 
>>presence and proper wiring.  It will be hard to prove that it works without 
>>removal or banging into the race car Really hard.
>>The Ford switch has been in production since the late 70's basically 
>>unchanged, and has very proven reliability.
>>
>>    
>>
>.  My 
>  
>
>>Weldon pump draws almost 20 Amps at working pressure and flow. (Methanol- 
>>100psig)