MicroSquirt.com read only forum (Jan.15,2018)

here's pics of my microsquirt candidate

this is where I'm thinking of mounting the unit.

A shot of the intake man. . The two little rectangle ,boss looking things might be a good plce to mount the injectors

and one overall pic of the unit

I have found a place to put the fuel pump and press. regulator. I will be a long way from the motor. Steel braded line will be used to make the run. I am thinking that the alum. box under the air cleaner, mounted to the carb is a good place to put an ATS.

The motor does not need fast Idle for warm up so I will eliminate that. (open to suggestions)

How can I make fuel rails for the injectors? My thought is maybe a"Y" connector.

Other things to figure out are: spark signal p/u, injector selection and what to do for relay's.

something I just thought of about this application is, at 1/4 turn of the throttle the TB will be WO. everything after that is against the governor.

How will that get prgrammed into MS? Possibly by RPM? Also, the MAP sensor will see WOT real early.

toon2 wrote:something I just thought of about this application is, at 1/4 turn of the throttle the TB will be WO. everything after that is against the governor.

How will that get prgrammed into MS? Possibly by RPM? Also, the MAP sensor will see WOT real early.

The MAP is going to register a difference in pressure whether you open the throttle or the governer opens the throttle, makes no difference. Your VE table is going to be tuned to RPM vs MAP so it does not matter what the governer does. It'll all be taken care of by your VE table.

You may have to do the fuel filter trick to condition the MAP signal to take out some of the major pulsations you may get with just a 2 cylinder.

MegaScott wrote:

toon2 wrote:something I just thought of about this application is, at 1/4 turn of the throttle the TB will be WO. everything after that is against the governor.

How will that get prgrammed into MS? Possibly by RPM? Also, the MAP sensor will see WOT real early.

The MAP is going to register a difference in pressure whether you open the throttle or the governer opens the throttle, makes no difference. Your VE table is going to be tuned to RPM vs MAP so it does not matter what the governer does. It'll all be taken care of by your VE table.

You may have to do the fuel filter trick to condition the MAP signal to take out some of the major pulsations you may get with just a 2 cylinder.

what is the fuel filter trick?

I guess you put a fuel filter in between the engine and the MAP sensor so smooth out the pulses from the engine before they get to the MAP sensor.

toon2 wrote: what is the fuel filter trick?

Basically the fuel filter trick is on installations where you have ITB's or a healthy camshaft, you install a MIG tip and a fuel filter to dampen out oscillations, especially during idle conditions.

see this thread for an example - http://www.msefi.com/viewtopic.php?p=156595

On the other issues, typically the injectors are fed from a "Rail" where fuel goes in one end and is pressure regulated from the other end, this ensures that the pressure at the injector is constant, and any air in the system is pushed out past the regulator to the fuel tank. If you place the injectors on the same "plane" when you design your intake you should not have any problem getting regular extruded aluminum fuel rail to work, or brazed steel fuel rails. Also you could use a tee and hose, that wouldn't be as good, but it would work.

For an ignition trigger you could use a VR sensor on the fan housing reading a strategically placed bolt head screwed into the flywheel.

I was just on the manufacturers web site and ran across an artical on adjusting the ignition coils. It looks like they use a magnet on the flywheel and some type of coil pack to distribute the spark. It also say's it's an electronic ignition. The only Pic. they had of it was on a PDF file.

Could this be used to somehow to trigger the MS??