Jump to content
HybridZ

ECU modifications to Megasquirt 1 Version 2.2 for 1983 L28et


benp

Recommended Posts

I recently bought a 280z with a 83 zx turbo swap. The car is running but not too well. It has a megasquirt 1 v2.2 ecu. I found the <a href="http://www.diyautotune.com/tech_articles/how_to_megasquirt_your_280zx_turbo.htm">How to MegaSquirt your 280zx Turbo</a> webpage. But the information is for version 3 not 2.2. From there I found <a href="http://forums.hybridz.org/topic/23244-megasquirtnspark-mssmsns-installation-guide/">MegaSquirt'nSpark MSS/MSnS installation guide</a> which is for version 2.2 . I've read through most of it and have a few questions. Looking at my board, XG1 & XG2 are jumped. Diode D8 has been removed and jumped. Which was covered in the installation guide. But X11 is jumped to one side of D17 (Injector LED), then a resistor jumps from there to R23. I've attached an image of my board below. Also X11 is jumped to X12 with solder. Im not sure if this was accidental or not. Also, the first relay on the relay board has been jumped. Is this the fast idle relay? The car has 460cc RX7 injectors and the orignal zx turbo distributor and trigger wheel. Any help is appreciated.

 

 

Thanks

Ben

post-30209-0-27368300-1355707946_thumb.jpg

post-30209-0-29631800-1355707962_thumb.jpg

Edited by benp
Link to comment
Share on other sites

Could you describe what "The car is running but not too well" means? Does it start easy or hard? Does it idle by itself or do you have to keep your foot on the gas? Is it missing on one or more cylinders? Does it run smooth at low rpm or high rpm or does it run rough all the time? Is the car drivable?

 

As for the relay board, that is the fast idle relay and by the looks of it there's been a fire there. One of the nearby capacitors looks to be burned fairly bad. Does you car actually have a fast idle solenoid?

 

X11 (pin 25 on the DB37) solder jumped to X12 (pin 27 on the DB37) is probably not a big deal unless you have something hooked up to either of those pins. Not sure about your other jumpers, my experience is with a V3.0 board.

 

I would try to learn as much as you can from the previous owner, or whoever built and installed the MS box in the first place.

Link to comment
Share on other sites

The Car idles and runs fairly smooth after it has warmed up. It is running a little rich according to the wideband (LC-1). 11-12 afr at idle. I've been doing a lot of reading and still have a lot to learn. I am somewhat familiar with fuel and ignition tables. This is the motor that was on pinks. It has been through a couple of people and cars before this one. I am trying to decide if I should buy a newer version of megasquirt. If this megasquirt is wired up correct and working, I will probably keep it for now. When installing MSnS on v2.2 to control ignition, the fast idle terminal is hooked to the GM HEI module, and the relay needs to be jumped? I will check and see if anything on the relay board is hooked to X12 or X11. I cant find anything that says X11 needs to be jumped to D17 for the L28et.

 

 

Thanks

Ben
Link to comment
Share on other sites

Yeah that looks like it was very hot at one time. wish i could help with the 2.2 but i run 3.0 but i may still have my stock tune saved for l28et with stock injectors as well as 450cc dsm injectors. I will check and if so i will help you out. I drove on it for like 9 months triggering off the distributor like you and get 25-28 mpg. Also being very conservative and timing and fuel. Maybe (xnke) will chime in on the wiring of your board, mine was the 3rd or 4th one he built. good luck man.

Link to comment
Share on other sites

Idling rich with big injectors is normal for MS1. MS1 has an injector pulsewidth resolution of .1ms, whereas MS2 can do .01ms. Without going into all the details, with your big injectors on MS1 you won't be able to fine tune the pulsewidth enough to get a nice and stable idle near a stoichiometric AFR. Yours is idling at 11-12 AFR which is about as good as you'll get. I am running MS1 V3.0 with 440cc injectors and my idle AFR is about where yours is, maybe a bit lower. You may be able to use the "hi res" code which you can read about here, but I wouldn't worry too much about it unless you have neighbors (or a wife... ask me how I know) complaining about all the exhaust smell as the car idles in the driveway. You may consider posting your .msq here so we can take a look at it.

 

EDIT: I have not personally done this, but I have read of other people lowering the static fuel pressure (slightly) to make the injectors behave as if they were a bit smaller. However, the lower the rail pressure the less efficient your injectors will be at atomizing the fuel, so you can only go so far. Do you know what your static fuel rail pressure is? Most injectors I believe are typically set at about 42psi static pressure.

Edited by OhBilly
Link to comment
Share on other sites

redzedturbo, i'm not trying to hijack this thread but what have you experienced between the 3.57 and the 3.0 that you like the 3.0 better other than being easier to mod or solder on? I own a 3.57 and am in the process of assembling a 3.0 i'm trying to compare the 2 myself?  Might also give BenP an idea of what to purchase if he does decide to go with an MSII.

Link to comment
Share on other sites

I was the one comparing 3.0 & 3.57. I don't like the 3.57 currently just because it just doesn't work well for me. I couldn't find info to set it up as info seems more abundant for the 3.0 and to this day ignition still doesn't follow the ignition map. It's just stuck at 30*. And it's the third megasquirt I've done so it should have been the easiest but was not the case. Also the box gets really hot and the engine starts cutting out after about a 20 mile drive. I've done everything to try to correct this. With my 3.0 that I assembled myself I can drive 80 miles to the dragstip, make 10 passes without much cooling time and drive 80 miles home and the car never misses a beat.

Link to comment
Share on other sites

I was the one comparing 3.0 & 3.57. I don't like the 3.57 currently just because it just doesn't work well for me. I couldn't find info to set it up as info seems more abundant for the 3.0 and to this day ignition still doesn't follow the ignition map. It's just stuck at 30*. And it's the third megasquirt I've done so it should have been the easiest but was not the case. Also the box gets really hot and the engine starts cutting out after about a 20 mile drive. I've done everything to try to correct this. With my 3.0 that I assembled myself I can drive 80 miles to the dragstip, make 10 passes without much cooling time and drive 80 miles home and the car never misses a beat.

Could you post a copy of your tune file and a data log of the engine running? This would give me a bit more info about what's wrong on this one.

Link to comment
Share on other sites

How do I make a data log?

With MS powered up and while connected to Tunerstudio or Megatune, hit ALT-L. This will bring up a "save as" dialog and you can make the filename whatever you want it to be (or leave it as is). When you hit ENTER, it will start datalogging. When you turn off the car, the file will automatically be saved. Then you can use Megalogviewer or Excel or whatever to view the datalog. The datalog is a simple file saved in a comma separated variable (CSV) type format.

Link to comment
Share on other sites

I was the one comparing 3.0 & 3.57. I don't like the 3.57 currently just because it just doesn't work well for me. I couldn't find info to set it up as info seems more abundant for the 3.0 and to this day ignition still doesn't follow the ignition map. It's just stuck at 30*. And it's the third megasquirt I've done so it should have been the easiest but was not the case. Also the box gets really hot and the engine starts cutting out after about a 20 mile drive. I've done everything to try to correct this. With my 3.0 that I assembled myself I can drive 80 miles to the dragstip, make 10 passes without much cooling time and drive 80 miles home and the car never misses a beat.

Thanks for the info and sorry for the mix up with what user posted.  I'll let you know if I notice the same thing once i get my 3.0 assembled.

Link to comment
Share on other sites

That one has the MSQ in it fine, but no log. I'd need to see a log of the problem happening to see what's going wrong. Nothing in the tune really jumped out at me other than that the spark map is the default one for a small block Chevy, and that you'll need to make sure that the V3.57 is actually set up for D14 as spark output and not JS10.

Link to comment
Share on other sites

Seems to have a considerable amount of noise.  Could be part of the problem.  I saw one huge spike at about the 84 second mark it happened right after the battery voltage flickered to 13.5, a whole volt drop.  Does the car act worse once its warmed up all the way? Also reading back through your posts you said your timing is stuck at 30 no matter what you do to the map.  Have you checked your basic settings to make sure you don't have the fixed timing set in there as a static value?  If you do, it won't matter what you change on the timing table.

Edited by motomanmike
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...