MicroSquirt/MegaSquirt vs OEM ECU

FIntruder · Post by **FIntruder** » Sat Apr 28, 2007 8:42 am

Is the processor speed of OEM ECUs the same as the various m/Msquirt combinations? Other than the flexibility and tuneability is there any advantage to changing a stock ECU to a micro or Mega Squirt?

newtyres1 · Post by **newtyres1** » Sat Apr 28, 2007 10:49 pm

I don't know about processor speeds but I think the most important things are 1) that the processor is fast enough to do the job well and 2) that the code is good and stable and 3) that the whole package works well and can be tuned to give the desired result. For example, a super-fast processor is useless if it isn't running good code, or the tuning software is a nightmare to use.

Other than the flexibility and tuneability is there any advantage to changing a stock ECU to a micro or Mega Squirt?

If the motor with the stock ecu has good warmup characteristics, driveability, economy, power, throttle response and AFR ratios, and there really isn't any room for improvement, then it would be a waste of time and money fitting a MS unless you simply want to learn about EFI and EFI tuning, and/or are planning future mods. Nearly every stock EFI vehicle I've driven has at least one or more minor deficiencies at least, and there's only one so far that I can't really fault.

Ian.

FIntruder · Post by **FIntruder** » Sat May 19, 2007 9:40 am

I figured it was more than fast enough I was just curious how much faster than OEM or even what OEM processing speed was. Like when someone has dial up and a new super fast computer, the weak link is still the modem speed and will be slow no matter how awesome the computer is.

MegaScott · Post by **MegaScott** » Sat May 19, 2007 1:26 pm

True that the MS2 cpu has plenty computing power left. Really the advantage to having overhead is that increasingly sophisticated algorithms can be used such as X-tau and EAE, as well as better control for EGO, boost, and other controls where there is an advantage to crunching the numbers faster, yet there is plenty of time to execute the basic EFI functions that count the most.

Fred Bloggs · Post by **Fred Bloggs** » Mon Jun 04, 2007 6:42 am

Maybe you'll permit me to hijack this thread a little, but on topic

I have a 97 Buell S1 with a Mikuni HSR42 Carb fitted rather than the OEM Keihin. The Fuel Injection fitted to later 1203cc Buells, the X1 and now XB12 etc... seems a big improvement to both the Keihin and the Mikuni.

Now may be the time to seriously consider a Micro Squirt. The bike has a Dyna 2000 twin fire ignition set up that I aim to keep. Perhaps fit a Dyna Single Fire Coil kit to it. (The ignition is switchable twin/single fire).

So I want a Fuel only installation. I can buy a Buell throttle body/tps/injectors setup from a Buell X1 that will bolt on. I have a friend who has developed software to read the VE, Fuel etc... tables from a Buell ECM. Would I be able to use the data from a Buell ECM to populate the tables required to run a Micro Squirt, fuel only

I'd prefer to set it up open loop without a Lamda is possible too. At least to begin with.

Is this feasible

MegaScott · Post by **MegaScott** » Mon Jun 04, 2007 9:23 am

Fred Bloggs wrote:Maybe you'll permit me to hijack this thread a little, but on topic

I have a 97 Buell S1 with a Mikuni HSR42 Carb fitted rather than the OEM Keihin. The Fuel Injection fitted to later 1203cc Buells, the X1 and now XB12 etc... seems a big improvement to both the Keihin and the Mikuni.

Now may be the time to seriously consider a Micro Squirt. The bike has a Dyna 2000 twin fire ignition set up that I aim to keep. Perhaps fit a Dyna Single Fire Coil kit to it. (The ignition is switchable twin/single fire).

So I want a Fuel only installation. I can buy a Buell throttle body/tps/injectors setup from a Buell X1 that will bolt on. I have a friend who has developed software to read the VE, Fuel etc... tables from a Buell ECM. Would I be able to use the data from a Buell ECM to populate the tables required to run a Micro Squirt, fuel only I'd prefer to set it up open loop without a Lamda is possible too. At least to begin with.

Is this feasible

Depends on what the Stock ECM is using for units and the method you are going to use for fueling after installing the Microsquirt. Since the oddfire Harley Motor has no real plenum and the pulses are so far spaced, most people use the alpha-n method for fueling these things using Megasquirt.

I know at least one guy (newtyres1) running a Buell using a regular Megasquirt-1and Hires code in Alpha-n mode. He has tuned his bike using a Tech edge wideband and a palm. Right now though I don't think palm tune supports MS2 (microsquirt) but I could be mistaken.

You could import your VE data from the stock ECU, or import data from a Buell already running on Megasquirt, I would think the Megasquirt-1 VE table would be closer to working right using the Microsquirt.

Fred Bloggs · Post by **Fred Bloggs** » Mon Jun 04, 2007 12:05 pm

MegaScott, great info thank you. I'll collect a few more bits and pieces in time for the uS release.