onDjuice

I've been reading up on this medasquirt thing to get rid of the opti. Looks like it can be done for about $1000 bucks. Would like some input from others who have gone this way. And if this is the right way to go.

Smokedavette

I have the megasquirt system on my 1956 Unlimited Street turbo VW on methanol with NOS, there is huge support for it with a few forums available. You can tune from your laptop and many tunes are available for download to get you started and there are several tuning applications as well.

It's really the least expensive, best supported system in existence. The ECU is pretty much unlimited in what it can do. I have mine setup to control boost, when to turn on the NOS, *data log, my map sensor is upgraded to handle 40 PSI of boost, you can run COP ignition with it and much much more. Oh and make sure you get some sort of wide band sensor like the LM1 that I have, it sends it's info to the megasquirt to help it tune itself.

Some links to help.*

http://www.msefi.com/

http://www.megamanual.com/index.html

This one has some good links and it's where I get my Megasquirt parts from.

*http://www.diyautotune.com/msmoreinfo.htm

LT401Vette

I have a 93 that has been running on MegaSquirt since 2005. It used to be an MS1 running MS1Extra, but now it is running on an MS3 with MS3X. The MS3 with MS3X is great, it has all the IO for just about anything you will ever need to do without any customization, just buy it and wire in the wiring harness.
I still run the stock ECU in piggyback for the gauge cluster, it is not actually running anything in the car at this point except the gauge cluster

But while I am 100% behind MegaSquirt, if your only goal is to remove the Opti-Spark, that isn't really the purpose. It can, but cause it is very flexible and can run with just about any ignition trigger system, but you will still need to replace the Opti with something.
In my case I am using a 60-2 tooth wheel on the crank with wasted spark coil packs. Soon planning to get a cam sensor in it so I can run it in full sequential.

It is really a stand alone ECU. So, if you are running many aftermarket parts, need easy tuning or want to manage things like boost controllers, waste gates, NOS, etc. I definitely recommend MegaSquirt. However, if you just want to replace your opti-Spark, I don't think you would want to take on a full ECU replacement.

onDjuice

Thanks LT401Vette. I'll keep reading up on it.

Smokedavette

Lol I spent days reading up on it in the beginning. The megasquirt forum is a very busy place with tons of help to get you going if you decide to go that way.

There is a lot of help for our engines since they are used in many hot rods and street rods.

onDjuice

Agreed. I just dont want to buy something that i will not need.

91blkvette

401... having just bought a MS3/MS3X and trying to understand the install, where did you install yours? Did you have any issues with sharing sensors with the GM ECU?

LT401Vette

You can share TPS or MAP sensors, but the not the temperature sensors. That would throw off the bias. It is easier to add new CLT and MAT sensors if you still need the readings to the stock ECU for any reason.

91blkvette

How is the 700R AT and the brake light wired to the MS3/MS3X ?

LT401Vette

Check this site out:
http://msextra.com/doc/ms3/lockup.html

You can pic which output line you want to use. Use any mid current output that you aren't using.

91blkvette

How time flies.

Installed my engine in Jan, added new AT in April, and not able to try to fire it up until Sept. What seemed like a fairly straight forward install (on paper) has been complicated by reality.

Lessons learned. 4 hands and eyes are better than two. Read all instructions 10 times before you start (amazing how many errors are caused by not carefully reading and following instructions.

Hopefully I'll have a well running 427 controlled by a MS3/3X by the end of this month. I have a Superram on it now and I will be replacing that with a cut/welded Stealth Ram.

Then I can figure out what to do with a leaking rear seal on a brand new, never driven 700R AT that's dripping on my ARH headers.

aDigitalPhantom

I cant recommend Megasquirt to any one, but if are seriously going to use one you need to do all the work yourself and be an expert tuner.

You must have been reading a different Megasquirt forum then the one I know about. Yes I was going to use a MS3X with an LS, but it the 411 PCM I used works better with less hassle.


I would recommend the 24x conversion from EFI connection, with modding your harness, or buying one custom made for it over any Megasquirt.

dizwiz24

I think you guys that have dreams about removing the optispark are nuts.

Use a quality optispark (ex. Delphi for 95 thru 96), or gm acdelco for 92 thru 94 and you wont have issues.

You want an optispark with the mitsubishi sensor.

Add a vent to the 92 thru 94 system for reliable performance.

aDigitalPhantom

It seems to me that the LT1 is slowly losing support. IMO the LT1 needs all the options it can get. Who knows what people will use when no one makes optis anymore.

93 ragtop

Quote:

Originally Posted by chevyowner

I would recommend the 24x conversion from EFI connection, with modding your harness, or buying one custom made for it over any Megasquirt.

Let me start by saying I am no tuner!! A few years back, I checked into this setup but I didn't think it would work on a corvette. They show wiring kits for f bodies but not vettes. Do you know what it takes to actually tie one into a vette?
I agree we need options. I live 30 miles outside of Washington DC and I was able to find a tuner Ed Hutchins in Va. Beach. Its over 4 hrs one way, but that is the closest I could find (who is reputable) to tune a 93

89onlyZ51

Has anyone ever added code so the megasquirt can feed the driver info center? That would be cool, and I'd give it try.

aDigitalPhantom

Yes they will work on vettes, but EFI connection does not have wiring for the vettes. It should also be much easier to find someone to tune it with the LS PCM.

The big problem this conversion will have for your 93 is that the 93 is batch fire, and the 24x is sequential. The engine harness also has the windshield wipers, hvac system, and I may be forgetting some wiring in it.

A few options to make it work would be.
Rewire you existing harness. You would need to change the PCM connectors, rewire the injectors, add wires for the coils, and possibly add a few wires for the crank/cam sensors.

You could get a standalone harness, and separate the wiper and hvac wiring then tie the oil pressure, coolant temp, etc into the old engine harness.

tjabo

Phil, is it you?

How did you mount the 60-2 wheel?

dave_85

I have a MS2 Extra with Bluetooth in my 85. The Tuner Studio software is awesome. It has a auto tune mode that works great. I can data log with my Android phone. If you can solder, build it from a kit. Mine fits in the old ECM case.

aDigitalPhantom

I have the SMD 3.57 MS3X with a Bluetooth adapter and it makes a nice paper weight. I asked for help on a few Megasquirt forums and was ignored or simply insulted. A semi-local tuner could not tune it to run correctly. I spent about 1 month trying to get it to run right with the MS3X, and less then 3 days to get it running correctly with the 411.

I thought about selling it as-is no support of any kind, but it is not worth the hassle of trying stick someone else with that POS. If it were possible to transfer a license of TunerStudio, ShadowDash, and the log viewer. I could be tempted to sell the lot for about $500. Tunerstudio's auto tune is garbage also all it did was fatten it so much it could not run, and never stopped adding fuel.