Some of you have seen my 4.3 swap thread where I used the megasquirt fuel and spark control system with very good results.
I still think this system has great value for eliminating the AFM and opening up the air flow on the 22re and other engines... also the ability to tune for power at any rpm and altitude..
I thought some pictures of the tuning screen would be helpful to those of you who have some interest but still have not got your minds around it... so here you go.


This is the primary screen. The gauges are configurable you can have intake air temp, throttle position, IAC position etc.. just about anything the ecm has data for can be put on the gauge cluster...






and from the tabs you can drop down the Spark Table. Keep in mind that any cell on this table can be changed to what you want and the table values are programmable as well... if you want the timing to advance quickly then plateau at a certain rpm just plug in the numbers!
I ran it pretty advanced for a while then gradually shifted the whole table to retard it untill the occasional rattle ping went away... stout!






The Air Fuel Ratio table is where you plug in your target numbers when you are running a wide band O2 sensor. The auto tune part of the software will continue to slowly tune the AFR untill your targets are reached... A 13/1 ratio is considered max torque and 12.5/1 is considered max HP while a 16.5/1 will give you great fuel economy. Just don't go too lean under load cause you will melt pistons!!






The Volumetric Efficiency table or VE table is the actual pulsewidth for the injector... higher number means longer electric pulse to the injector which equals more fuel shot in the cylinder. These are the numbers that the auto tune changes to lean or rich the air fuel ratio to meet your targets.




My setup has the barometric correction activated where it compensates for the altitude... very helpful when you drive from West Texas to Colorado to run the trails like we did this summer. Every time you turn the key on it senses tha altitude and resets plus with the wideband o2 sensor and autotune its always correcting on the backside as well.
You can also fine tune the accelleration enrichments to take all throttle lag out which you can't do with a stock setup!
I think its cool that you can build a tune to do what the factory ecm won't do which is maximize power and efficiency on any engine at any rpm or load.

This project has been fun and I am still tuning to increase efficiency. Last trip to Big Bend we got 16 mpg running 75 mph with suitcases and gear on the highway and well over 20 mpg when I ran the slower runs.


Imogene Pass '09 , 13,144 ft

 

Very cool & geeky. I had researched MS a lot in the past, but I guess I am turning into a softy in my old age...never followed thru with it. Thanks for sharing.

 

Hottt. set up.

 

The first time we got a Megasquirt package I didn't think it was what it is.
My husband likes it about as much as if it was what I was thinking....

 

Did you purchase the finished squirt or did you build yours? I would love to get my hands on one, but I think I am in over my head looking for the right one. Are you using the unit for the 22R?

(another stupid question, what is a Gary Fisher?)


anyhow, an excellent build, I will try to keep my eyes out for updates!

 

I know the first question's not for me but my husband built his and has had it for several years now. He's got it set up to run both e85 and regular gas and is constantly tweaking it for better performance. He really likes it. His is in a Volvo 240, but it's not a 240 as we know it.

Tacoclimber is referring to my Gary Fisher Supercaliber mountain bike.

 

What I do not understand is how you wire in the ignition system into this. Every ignition system uses different pulses. I'm doing a 4.3 TBI swap in mine but I'm using the factory GM computer and harness. I thought of using MS but I see no benefits for the extra money. I'm leaving the engine stock so I do not need to tune it. I remember reading on Pirate guys getting 14-18 MPG on the stock Chevy electronics. Also is their a guide on where to start on your fuel and spark maps? How do you know where to begin? Also another reason I did not get MS was I did not want to keep tweaking the computer. I want to set it and go. Sick and tired of dicking with vehicles as it is.

James

 

It's certainly not for everyone... I kind of like playing with the different tunes to see how it reacts. Power is the big objective for me, you just can't build as much power with a stock unit.
I am running a Ford distributorless ignition system with a custom trigger wheel because its plug and play with the MS.
The fuel and spark maps come preloaded for a chevy 350 so they are very close for the 4.3
But if you are sick of playing with the tune and want something thats very close just stay with the stock setup honestly its good enough.

 

I bought the pre built kit to save time.

It takes some research to get the hang of it but there is alot of good info on the MS websites.

I am running a Chevy 4.3 vortec but the ecm is programmable for just about any setup.. when you configure it you set all of the specifics for # of cylinders, type of injectors, displacement etc...