Conversion from Carb to EFI

[mylesm260]

Re: Conversion from Carb to EFI

I am a megasquirt guy myself.

The system is very DIY, and it's only as good as you make it, but being open source, it lets you customize it any way you like.

There is a massive community behind it, and there is support for all kinds of custom projects.


The standard magasquirt is MAP based, which is fine, except you essentially need some kind of feed back (o2) in order to tune it properly.

Because it's open source, people have written the codes to use MAF, instead of map, so converting is super simple.

Also, it has support for pretty much any triggering input you want (including the GM vortec crank angle sensor)


My only REAL beef with the system is it uses a PC style D Connector, soldering wires to it is somewhat challenging.


But, you can buy complete units for 300 bucks, and have it installed and running in a saturday. And because it's open source, there's tons of other people on the forums who have already tuned their megasquirt for you're engine, so you can just ask them for their tunning and upload it to yours.

Megasquirt

 

[RayTCraft]

Re: Conversion from Carb to EFI

Great!
Thanks again everyone. I may go look for a 96 or newer complete engine instead of using the 94. If anyone has any comments as to whether this would be worthwhile let me know. If I was to go with the 96 or newer than would it be best to use the EFI that comes with it or go to another. The megasquirt, do you buy the system designed for marine specific application and engine specific?

 

[n2ostroker]

Re: Conversion from Carb to EFI

If you don't like the db37 connector you can get the eMs-pro and it uses automotive type connectors and a premade harness. Most vendors also carry the 37 pin connector in a screw down terminal as well.

Dennis Moore as well as many others carry a block to add an o2 sensor between the manifold and riser so that isn't a problem. You can do all the tuning you need. If you want a more rugged sensor you'll have to spend some cash though. You could look at the NTK sensor or the Bosch sensor they use on dyno's. Expensive but very accurate and durable. ou're still left with buying a wideband controller like an LC-1 or LM-1. Or you could use one like the AEM or NGK that comes as a controller and display all in one. You don't want the sensor down at an exhaust port as you'll most kill it in short order not to mention skew the readings quite a bit.

I would definitely stay with a MAP system in a boat. It would be super easy to tune since there is only so much variance in load on a marine engine.

As for ignition, MS supports pretty much any ignition you can think of. GM dizzies just use a hall sensor which you can take straight into the MS and do any spark control. You can also use the crank sensor if you're running distributor less. They also have full sequential injection setup now but that would require a crank and cam position sensor.

Any efi system mentoned will work and work well. he end result is in the setup and the tuner. They only do what they're told. Having used a few and setting up a few MS's myself I would much rather go the MS route if choosing a stand alone system. Cheaper and I can choose almost an option I want. A MS-1 3.0 will do anything you could ever think of on a boat and give easy starts, better mileage and unlimited tunability.

 

[n2ostroker]

Re: Conversion from Carb to EFI

Then again on a boat a properly setup carb will do what just about anyone here would want if you learn how to read plugs. The only downside is you're stuck with set ignition curve from whatever module you use.

 

[ryendube]

Re: Conversion from Carb to EFI

Damn those systems are cheap. hmm looks like I have a new product to hobby with.

dont think i will be adapting my truck to it simply cause i already have all the stock features wired up, a/c, fans, pwr steering etc. next project im going to give it a try.

thanks for introducing me to this system.




cool thing I saw was 24x reluctor installed to enable coil over system. Looked really promising.

 

[ryendube]

Re: Conversion from Carb to EFI

adding to my previous post if they had a straight stock ecm plug n play to MS id use it in a secound. or if i could find a donor stock ecm to tear the plugs out to make an adapter. after the hours spent adapting the newer harness to the older truck ( i have the dash and everything hooked up) I cant bring myself to chop it up.

 

[n2ostroker]

Re: Conversion from Carb to EFI

Damn those systems are cheap. hmm looks like I have a new product to hobby with.

dont think i will be adapting my truck to it simply cause i already have all the stock features wired up, a/c, fans, pwr steering etc. next project im going to give it a try.

thanks for introducing me to this system.




cool thing I saw was 24x reluctor installed to enable coil over system. Looked really promising.

They're not as cheap as made out to be. By the time you ad options and a wideband, replace needed sensors if needed you'll be a good bit over $300, especially if you buy a premade system. Still you can have a fully optioned stand alone with wideband for under $1000 it's a hell of a deal. The only bad thing is they are open source and not manufacturer supported so you can't just make a phone call with a problem. Check out www.diyautotune.com. I've dealt with and ordered a few systems from them and they are some of the most knowledgeable people around with MS.
If you can source parts from a junk yard like plugs and harnesses you could totally build a plug and play system especially on a GM system since most sensors and plugs are based on GM standards.

 

[winner228]

Re: Conversion from Carb to EFI

the cams part #'s are all the same from the s10 to the 4wd 1500 truck to the awd astro van for all vortec motors.

 

[mylesm260]

Re: Conversion from Carb to EFI

adding to my previous post if they had a straight stock ecm plug n play to MS id use it in a secound. or if i could find a donor stock ecm to tear the plugs out to make an adapter. after the hours spent adapting the newer harness to the older truck ( i have the dash and everything hooked up) I cant bring myself to chop it up.

I actually did that for my 1991 nissan pathfinder.

I took a wrecker ECU, and used an angle grinder to grind the wiring harness connectors off the PCB.

Then I made an adapter.... plug and play megasquirt using 100% stock vehicle wiring.... just had to run the vacuum line for the MAP sensor... pretty nice....

Unfortunately though while tunning, I ran rich and melted out my cat... good thing it was flanged...

 

[mylesm260]

Re: Conversion from Carb to EFI

the cams part #'s are all the same from the s10 to the 4wd 1500 truck to the awd astro van for all vortec motors.

That's what I initially thought...

I know the 180 HP versions have restrictor plates on the intake, as well as different ECU part numbers....

Someone on here said the 180 hp and 200 hp's also had different cams as well.

 

[winner228]

Re: Conversion from Carb to EFI

nope all the same. thats why i think a merc cam is hotter.

 

[mylesm260]

Re: Conversion from Carb to EFI

it's not

http://www.bucksengines.com/Data/24.pdf

this explains all the differences (or lack there of) between the marine and truck motor

it also shows the exhaust restriction and the intake restriction with both
as well as the cam specs, during, lift, etc


What I DO know for absolute certain is the 180 HP versions of the 4.3 vortecs have a restrictor plate mounted to the throttle body.

I've also been told that they have different ECU's

 

[QC]

Re: Conversion from Carb to EFI

I cannot believe the words Stoichiometric and Three Way Catalyst are absent from this thread . . .