LocostUSA.com

Learning how to build Lotus Seven replicas...together!
It is currently March 28, 2024, 4:14 am

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 35 posts ]  Go to page 1, 2, 3  Next
Author Message
 Post subject: OEM vs Megasquirt
PostPosted: July 7, 2017, 7:31 pm 
Offline
User avatar

Joined: August 8, 2014, 6:08 pm
Posts: 1238
Location: Green Bay, WI
Ok all you gurus of the electronics. I need to be buying an ECM. With the OEM mazda computers can you omit using stuff like emissions and idle air circuits you name it. I have a bare bones set up (surprise right).
Or do i absolutely have to do a programmable unit? All the advice I can get will be very valuable. Back story is all I have is the 18" of harness mazda has for fuel injection wiring. I have no donor car so this is literally from scratch. The biggest hurdle I have see so far is an OEM pigtail. I can't seem to find one. If i can use that avenue. I really would like to run just a stock set up to get it on the road. In my mind its the easiest and cheapest (I think).

Thanks guys. :cheers:

_________________
Steve

My build : http://www.locostusa.com/forums/viewtop ... 35&t=17160

MGB/GT V8 5.0L. viewtopic.php?f=36&t=20782


Top
 Profile  
Reply with quote  
 Post subject: Re: OEM vs Megasquirt
PostPosted: July 7, 2017, 8:21 pm 
Offline
Mid-Engined Maniac

Joined: April 23, 2006, 8:26 pm
Posts: 6410
Location: SoCal
Short answer: No.

Longer answer: There "may" be modified versions of the OEM ECU that allow what you want (I know there are for Hondas) but you'll have to confirm. Aftermarket units absolutely will do what you want but cost more. That said, prices are coming down. You can buy already-built kick-butt units that are probably better than the OEM unit for around $1000 - BUT, they will need tuning and if you don't do it yourself, could get very expensive.

_________________
Midlana book: Build this mid-engine Locost!, http://midlana.com/stuff/book/
Kimini book: Designing mid-engine cars using FWD drivetrains
Both available from https://www.lulu.com/


Top
 Profile  
Reply with quote  
 Post subject: Re: OEM vs Megasquirt
PostPosted: July 7, 2017, 8:32 pm 
Offline

Joined: April 1, 2010, 10:26 am
Posts: 564
If you going to keep the motor stock, then OEM might be the best way, but if you plan on something like turbo charging then I would go aftermarket now and save time and money down the road.

Graham


Top
 Profile  
Reply with quote  
 Post subject: Re: OEM vs Megasquirt
PostPosted: July 7, 2017, 8:34 pm 
Offline
Mid-Engined Maniac

Joined: April 23, 2006, 8:26 pm
Posts: 6410
Location: SoCal
But he asked whether ancillary stuff like all the emissions stuff could be disabled - I don't think it can. I guess the real question is, what does the factory ECU do about it if half the emissions stuff is disconnected. If it does nothing, yeah I vote for going OEM, but it may also put the car in some degraded mode.

_________________
Midlana book: Build this mid-engine Locost!, http://midlana.com/stuff/book/
Kimini book: Designing mid-engine cars using FWD drivetrains
Both available from https://www.lulu.com/


Top
 Profile  
Reply with quote  
 Post subject: Re: OEM vs Megasquirt
PostPosted: July 7, 2017, 10:38 pm 
Offline
User avatar

Joined: June 8, 2010, 8:02 pm
Posts: 621
Location: White Rock, BC, Canada
Every manufacturer and model is different. Some ECUs have been cracked and can do just about anything you want with just a re-flash using the appropriate software/cable. I use HP Tuners for GM and Ford stuff and it's usually good. I know some Mazdas are tunable this way, but you will have to look into your specific model and see if there is software to do what you want. I'll always stick to OE hardware when possible as it is usually proven and dead reliable.

Cheers.

_________________
Build log: viewtopic.php?t=9291


Top
 Profile  
Reply with quote  
 Post subject: Re: OEM vs Megasquirt
PostPosted: July 7, 2017, 11:35 pm 
Offline
User avatar

Joined: August 8, 2014, 6:08 pm
Posts: 1238
Location: Green Bay, WI
I am almost certain with any unit I'll have MAP sensor and O2 sensor as well what eles do I have to concider for emissions. We don't have testing here to contend with so not a worry. I can get a computer for $100. Pigtail? IDK. The megasquirt is $450. Microsquirt $350. All 3 need custom
wire. Am I looking at this too simplistically?

_________________
Steve

My build : http://www.locostusa.com/forums/viewtop ... 35&t=17160

MGB/GT V8 5.0L. viewtopic.php?f=36&t=20782


Top
 Profile  
Reply with quote  
 Post subject: Re: OEM vs Megasquirt
PostPosted: July 8, 2017, 5:40 am 
Offline

Joined: February 28, 2009, 11:09 pm
Posts: 1307
Location: Connersville, Indiana
I think you will probably not be able to use a stock ECU without some sort of retune. So it becomes $100 + retune vs $350. Buying a stock ECU without KNOWING that it can be retuned is buying a $100 lottery ticket. How good is user support for retuning the stock ECU? Megasquirt and Microsquirt certainly are not perfect, but can work with any engine modification. User support is top notch.

If you tune your engine according to Megasquirt directions, it will not be obvious you are running "dirty". A smoky, stinking exhaust means your engine is not tuned for optimum performance.

Bill


Top
 Profile  
Reply with quote  
 Post subject: Re: OEM vs Megasquirt
PostPosted: July 8, 2017, 7:02 am 
Offline
User avatar

Joined: December 7, 2012, 8:28 am
Posts: 1410
Location: Sarasota
What is the year and model of your engine? It's probably best to find out from someone who has used your engine or similar model. When researching engine stuff (Honda S2000) I typically get on the S2000 forums, they have more specific knowledge.

_________________
2015 & 2016 EMod Florida State Autocross Champion
2013 & 2014 DSP Florida State Autocross Champion

Scrap Metal Build Log viewtopic.php?f=35&t=14558


Top
 Profile  
Reply with quote  
 Post subject: Re: OEM vs Megasquirt
PostPosted: July 8, 2017, 7:57 am 
Offline

Joined: April 1, 2010, 10:26 am
Posts: 564
Also check on the cost of new harnesses. For the Honda engine they were inexpensive, the injection and power harness were about $125 each. It's so nice working with new wiring. A lot of the spare parts I have got for the Honda are inexpensive. A very complex gasket that sits under the VTEC unit. Looks like a squashed figure of 8 O ring, one section has a metal mesh strainer was only $8. Tundra, you using a Duratec? There are many options available, every Carerham has a Duratec. Maybe hop on the USA7s.net list and see what you can find out.

Graham


Top
 Profile  
Reply with quote  
 Post subject: Re: OEM vs Megasquirt
PostPosted: July 8, 2017, 9:58 am 
Offline
User avatar

Joined: August 8, 2014, 6:08 pm
Posts: 1238
Location: Green Bay, WI
FastG wrote:
Also check on the cost of new harnesses. For the Honda engine they were inexpensive, the injection and power harness were about $125 each. It's so nice working with new wiring. A lot of the spare parts I have got for the Honda are inexpensive. A very complex gasket that sits under the VTEC unit. Looks like a squashed figure of 8 O ring, one section has a metal mesh strainer was only $8. Tundra, you using a Duratec? There are many options available, every Carerham has a Duratec. Maybe hop on the USA7s.net list and see what you can find out.

Graham


Graham Its good to talk to you again!, I think by now you moved?. I was going to try to get to Chicago to see you do a track day this summer. Oh well.
Its a 93 Mazda 1.8L DOHC. Should have found a honda. Their is nothing cheap about this thing. I called Ford looking for pig tails so I could do my charging circuit wiring ford stopped caring stuff for this engine. They used the engine as well in Escorts. When I called Mazda they only sold Harnesses no pigtails. The only thing I have to hook up is a coil, Tps, Mass air,O2, Cam positioner, water temp and the injection harness. Correct me if I missed stuff. I think by the time i piece it together just do the diy megasquirt. How much of a pain is the tuning on the DIY megasquirts? Which module do you pick?

_________________
Steve

My build : http://www.locostusa.com/forums/viewtop ... 35&t=17160

MGB/GT V8 5.0L. viewtopic.php?f=36&t=20782


Top
 Profile  
Reply with quote  
 Post subject: Re: OEM vs Megasquirt
PostPosted: July 8, 2017, 1:02 pm 
Offline

Joined: April 1, 2010, 10:26 am
Posts: 564
Steve your correct I am now in Maryland, just did the 24 car track weekend at NJMP. As your Miata powered. Look at the turbo Miata list. there is a guy there Brainiak or something like that, has built 100's on Miata megaquirts, I bet he can help you ourt

https://www.miataturbo.net/megasquirt-18/

Graham


Top
 Profile  
Reply with quote  
 Post subject: Re: OEM vs Megasquirt
PostPosted: July 8, 2017, 1:12 pm 
Offline
User avatar

Joined: December 7, 2012, 8:28 am
Posts: 1410
Location: Sarasota
I would probably try the scrap yards (pick and pull) for the wiring harness. I have heard Megasquirt is easy to use and has a huge following so you should have no issues finding setup tutorials.
I did the tutorials to get everything calibrated and working, set up idle and did a basic tune to get reasonable AFRs then went to the dyno to get it all dialed in by a professional ($400 for about 6 hours plus lots of good advice to get more out of the engine).

The aftermarket ECU for the S2000 engine allows you to lower the VTec which picks up 20-30 midrange hp and tq. Typically you can expect to gain 10% across the board with a good tune on a NA engine.

You won't have a standard intake, exhaust, less parasitic loss, lighter drivetrain etc. An aftermarket ECU can take advantage of these things where it could be a hinderance to a stock ECU..

_________________
2015 & 2016 EMod Florida State Autocross Champion
2013 & 2014 DSP Florida State Autocross Champion

Scrap Metal Build Log viewtopic.php?f=35&t=14558


Top
 Profile  
Reply with quote  
 Post subject: Re: OEM vs Megasquirt
PostPosted: July 8, 2017, 1:42 pm 
Offline
User avatar

Joined: August 8, 2014, 6:08 pm
Posts: 1238
Location: Green Bay, WI
FastG wrote:
Steve your correct I am now in Maryland, just did the 24 car track weekend at NJMP. As your Miata powered. Look at the turbo Miata list. there is a guy there Brainiak or something like that, has built 100's on Miata megaquirts, I bet he can help you ourt

https://www.miataturbo.net/megasquirt-18/

Graham

Thanks I'll check it out. Just took a look and there's lots of threads Thanks.

_________________
Steve

My build : http://www.locostusa.com/forums/viewtop ... 35&t=17160

MGB/GT V8 5.0L. viewtopic.php?f=36&t=20782


Top
 Profile  
Reply with quote  
 Post subject: Re: OEM vs Megasquirt
PostPosted: July 8, 2017, 1:44 pm 
Offline
User avatar

Joined: August 8, 2014, 6:08 pm
Posts: 1238
Location: Green Bay, WI
wrightcomputing wrote:
I would probably try the scrap yards (pick and pull) for the wiring harness. I have heard Megasquirt is easy to use and has a huge following so you should have no issues finding setup tutorials.
I did the tutorials to get everything calibrated and working, set up idle and did a basic tune to get reasonable AFRs then went to the dyno to get it all dialed in by a professional ($400 for about 6 hours plus lots of good advice to get more out of the engine).

The aftermarket ECU for the S2000 engine allows you to lower the VTec which picks up 20-30 midrange hp and tq. Typically you can expect to gain 10% across the board with a good tune on a NA engine.

You won't have a standard intake, exhaust, less parasitic loss, lighter drivetrain etc. An aftermarket ECU can take advantage of these things where it could be a hinderance to a stock ECU..

I am leaning megasquirt to tell you the truth. I don't have that many wire groups to run.
Do you use a bulkhead connection on your firewall for your computer?. Those look like a nice feature

_________________
Steve

My build : http://www.locostusa.com/forums/viewtop ... 35&t=17160

MGB/GT V8 5.0L. viewtopic.php?f=36&t=20782


Top
 Profile  
Reply with quote  
 Post subject: Re: OEM vs Megasquirt
PostPosted: July 8, 2017, 1:56 pm 
Offline
User avatar

Joined: December 7, 2012, 8:28 am
Posts: 1410
Location: Sarasota
No I have a usb connected into the ECU and that is just shoved beside the transmission, I pull it out and connect it to my tablet which sits on the steering wheel. You could easily make it look nice with a USB extension or similar.

_________________
2015 & 2016 EMod Florida State Autocross Champion
2013 & 2014 DSP Florida State Autocross Champion

Scrap Metal Build Log viewtopic.php?f=35&t=14558


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 35 posts ]  Go to page 1, 2, 3  Next

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 11 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
cron
POWERED_BY