MFI cold start solenoid amps

[derekw]

Hi all,

I'm replacing a manual cold start enrichment switch on my 1970 911E with a timed relay and wondered if a 10A relay would be sufficient. I believe there is an inductive load which may require a hefty relay? Any idea what amp rating the original "black" relays are?
thanks, Derek

[356RS]

A 10 amp relay would be fine. The solenoid draws less that 5 amps.

[derekw]

Thanks Mark!

[dicklague]

Why not put in a manual push button on the dash to manually start the MFI system. I have had this in my 2.7 1973 for almost 20- years and it works great.

The button supplies ground to the relay that actuates the solenoid.

[derekw]

As I said above "I'm replacing a manual cold start enrichment switch on my 1970 911E with a timed relay." I prefer a small timed relay to the manual switch.

[dicklague]

Originally Posted by derekw

As I said above "I'm replacing a manual cold start enrichment switch on my 1970 911E with a timed relay." I prefer a small timed relay to the manual switch.

I prefer to know what it is doing by......doing it myself.......I went through the "timed relay" waste of time.

I have a push button on the dash hooked to a relay that activates the fuel solenoid on top of the filter.

Starting is like using a "tickler" on one of my old motorcycles.

I also removed the cold start bi-metallic stack and installed an adjustment knob. Makes for good fine tuning on the run.

I do have a permanently installed AFR instrument. A good one made by Daytona Sensors and available from Pellican. I know all the time where my AFR is reading. I can make minor adjustments with the adjustment knob.

I have been running my 2.7 for almost 10 years with this setup.