RPM cut off swith ?

[Nacho-RT74]

is there somekind of aftermarket RPMs cut of switch/sensor assembly available ? I'm interested on cut the compressor at High RPMs. Let say 5000 ?

Note... WOT cut off switch at carb is not the same because you can get WOT but still somekind low RPMs

[A383Wing]

all the newer cars with fuel injection have the AC cut out at WOT...which is computer controlled....but it only cuts out at full WOT...not high rpm's which i s what I think you are asking for.

not sure how you could do it...you would have to have something monitor the rpm, then send a signal to a relay to cut power to ac compressor....sounds like a lot of work and wiring will be needed....

how about just install a cut-out switch somewhere and manually kill the power to compressor?

[John_Kunkel]

RPM activated switch:

http://www.msdignition.com/Products/RPM/Timing_Controls/RPM_Controls/8950_-_RPM_Activated_Switch.aspx

[A383Wing]

ok...simple enough....$100..... 

[Nacho-RT74]

ok...simple enough....$100..... 

what really makes it not that simple LOL

[Nacho-RT74]

juts read the instruction sheet... needs to be added an RPM chip, so is not $100, so a little bit more, due nothing is included on the switch

and will need to use an extra relay to cut the clutch feed, not due the amps like really to cut the power by deactivate some ground what triggers the positive to clutch

[Nacho-RT74]

how about just install a cut-out switch somewhere and manually kill the power to compressor?

already done by a guy from RR nest even better, and is posible, I already had though on that, but still will be throttle controled, not RPMs




Not bad, and cheap and easy to do it, but if done by RPMs, even better

[elacruze]

http://www.hewtechelectronics.com/rpmlimit.htm

"low cost" but doesn't give the actual price. Looks like it can trigger from a tach signal.

[Nacho-RT74]

sounds good!

there is another add to cost on the MSD deal instead the RPMs chip:

RPM selector 8672, but 6000 Rpms as the lowest setup, not bad, but 5000s range will be better I think at least for my purpouse.

( and still the WOT switch mounted on carb will be necesary... can be used to be able deactivate the Clutch on both situations )

[John_Kunkel]

ok...simple enough....$100..... 

Not if you'l accept used.

http://cgi.ebay.com/ebaymotors/MSD-8950-RPM-ACTIVATED-SWITCH-USED-_W0QQcmdZViewItemQQitemZ260731784454QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

[Nacho-RT74]

I was already watching it, but still thats because used. I can't see why new cost around $100, You shouldn't wait to find an used one for a reasonable priced piece

[Nacho-RT74]

well I think there are more reliable options around without need the RPMs chips

http://cgi.ebay.com/ebaymotors/Summit-Racing-RPM-Activated-Switch-830449-1-_W0QQcmdZViewItemQQhashZitem4cf4f05c9cQQitemZ330526907548QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

and it can be inverted to normally open or closed ground using same trigger wire, support 3 amps

http://static.summitracing.com/global/images/instructions/sum-830449-1a.pdf

and saving some bucks:
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=130363853963&ssPageName=STRK:MEWAX:IT

will need anyway a relay to deactivate the positive to clutch triggering the ground at relay...


or:
http://cgi.ebay.com/ebaymotors/Dedenbear-RPM-Control-Switch-RPM1-Standard-Ignition-New-/320651905720?pt=Race_Car_Parts&hash=item4aa857cab8