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

I am rebuilding an engine and was considering doing fuel injection. I have access to dyno's and lots of tech support at my school, but I am trying to get a little bit of information about the MicroSquirt system. My target price is 2,000 dollars for the project. I know where to get fuel rails and a fuel injection manifold. I also know a little bit about the different types of sensors. But...

1)It appears that all efi kits have some carburetor looking device that measures air flow and temperature? What is the name of this part (non-throttle body), and what does it do, and what instruments are contained within?

2) The engine is a v8 with a maximum expected hp/torque around 500 and is 446 cubes, what size injectors will I need.

3) Ignition. What are the options with the ignition as far as advance is concerned. Is it possible to retrofit some sort of crank/ camshaft positioning sensor in place of the distributor and run completely off of ignition maps.

4) Is microsquirt suitable for my application?

Thanks for your help.

bronco9588 wrote:I am rebuilding an engine and was considering doing fuel injection. I have access to dyno's and lots of tech support at my school, but I am trying to get a little bit of information about the MicroSquirt system. My target price is 2,000 dollars for the project. I know where to get fuel rails and a fuel injection manifold. I also know a little bit about the different types of sensors. But...

1)It appears that all efi kits have some carburetor looking device that measures air flow and temperature? What is the name of this part (non-throttle body), and what does it do, and what instruments are contained within?

You may be thinking of a mass air flow sensor, which Microsquirt does not need. It just needs an IAT sensor and a MAP sensor.

2) The engine is a v8 with a maximum expected hp/torque around 500 and is 446 cubes, what size injectors will I need.

42 lb/hr injectors should be about right.

3) Ignition. What are the options with the ignition as far as advance is concerned. Is it possible to retrofit some sort of crank/ camshaft positioning sensor in place of the distributor and run completely off of ignition maps.

With Microsquirt you will probably have an easier time using a distributor, although you could put a Ford EDIS system on there. You could use a stock Mopar Lean Burn distributor as they have the timing locked out. Or you could use one of many crank trigger setups on the market to trigger the distributor - there is little difference from an electronics standpoint between a Lean Burn distributor and MSD Flying Magnet. We also have a 36-1 wheel if you want a bit more resolution.

4) Is microsquirt suitable for my application?

Thanks for your help.

It certainly could work here, although a full-sized Megasquirt may open up a couple other options like using low impedance injectors or a distributorless ignition.

What are the differences between the micro/mega?

The Microsquirt has two channels of ignition output, supports up to 2 low impedance or 8 high impedance injectors, and works with on/off or PWM idle air control valves. It only comes in complete form and is a very small box (hence the name)

The Megasquirt-II (which is the version that has the same processor as the Microsquirt) supports up to 12 low impedance injectors or a similar number of high impedance ones. It can control on/off, PWM, or stepper IAC valves. Depending on what firmware and mods you have, it can support from one to six channels of ignition output, enough to run wasted spark ignition on a V8. It can be bought complete or as a build-it-yourself kit.

The "carburetor" lookin' item is the throttle body. Throttle Body Injection locates the injectors in the throttle body. Port Fuel Injection still uses a throttle body but the injectors are located very close to the intake port usually on the intake manifold. Either way ya still have a throttle body to control air flow. A carburetor with a Throttle Position Sensor on it could be used as a throttle body.

If I was converting anything except a motorcycle or other small engine which will have the ECU somewhat exposed, I'd go with a MegaSquirt.