LocostUSA.com

Learning how to build Lotus Seven replicas...together!
It is currently December 9, 2019, 7:50 am

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 138 posts ]  Go to page Previous  1 ... 4, 5, 6, 7, 8, 9, 10  Next
Author Message
 Post subject: Re: A locost EFI
PostPosted: September 22, 2015, 2:44 pm 
Offline

Joined: June 15, 2010, 8:29 am
Posts: 550
Location: Duxbury, MA USA
Actually now is a good time as I have a 2 week wait to get into the lab with my drug detection project...I now know so much more about induction heating than I ever wanted to know.
Send the files to my gmail account.

_________________
Parts left out cost nothing and cause no problems!!


Top
 Profile  
Reply with quote  
 Post subject: Re: A locost EFI
PostPosted: September 22, 2015, 3:43 pm 
Offline
User avatar

Joined: March 17, 2015, 8:10 pm
Posts: 15
Location: Jersey City, NJ
JPS Europa wrote:
Send the files to my gmail account.

https://github.com/ or http://sourceforge.net/ would be even better!

_________________
DIY ECU project - http://rusefi.com/


Top
 Profile  
Reply with quote  
 Post subject: Re: A locost EFI
PostPosted: September 27, 2015, 10:57 am 
Offline
The voice of reason
User avatar

Joined: January 10, 2008, 4:47 pm
Posts: 7634
Location: Massachusetts
Rusefi I am still debating this and don't know what to do yet. I registered on your site, I need to go make a post there now...


Here's an early look at the driver board. It has taken a couple of tries but here we have 8 channels of coil drivers, 2 chips to drive the coil drivers and injectors and another chip with 16 floating MOSFETs controlled by SPI.

The coil drivers are IRGS14C40L at the moment. There are many newer devices but this one seems to be specified for a large coil. Maybe all the modern coils are smaller these days. I'll need to double check the inductance of likely coils.

I took some guesses for dwell time and assuming 4 mS dwell and %50 duty cycle, each channel should be good for around 15,000 RPM. One of my first users is working with a motorcycle engine in a sports racer and he needs around 14,000 RPM so this is realistic.

My engine will be an eight and 7500 should be basically enough. Maybe I should make this board be 4 channel with wasted spark for 8 cylinder engines and devote the extra space to some more medium current drivers for H-bridge etc.

Anyway here's the pic with the layout still in progress. The SPI is mostly done and that's my big concern. It's harder than I expected but should be doable.I just have to grovel some more.


Attachments:
C9_DRV8a_early.jpg
C9_DRV8a_early.jpg [ 111.54 KiB | Viewed 1974 times ]

_________________
Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.
Top
 Profile  
Reply with quote  
 Post subject: Re: A locost EFI
PostPosted: September 27, 2015, 11:23 am 
Offline
User avatar

Joined: March 17, 2015, 8:10 pm
Posts: 15
Location: Jersey City, NJ
What is for debate and what are your concurns about GH and SF?

_________________
DIY ECU project - http://rusefi.com/


Top
 Profile  
Reply with quote  
 Post subject: Re: A locost EFI
PostPosted: September 27, 2015, 9:30 pm 
Offline
The voice of reason
User avatar

Joined: January 10, 2008, 4:47 pm
Posts: 7634
Location: Massachusetts
Quote:
What is for debate and what are your concurns about GH and SF?


Hi Andrey, I've worked with open source software for a long time and am comfortable with it. Right now I don't see any problem with contributing my code under the GNU or other license.

I am less sure about the schematics and especially the board layout. I don't think there are any strong protections from copyright etc. A drawing is different than something that is written like code. If you copyright a drawing, it can be changed a bit and it is no longer the same. If something is writing, you can change fonts or spacing etc., but it is still the same text.

The manufacturer of the chip I use has a general reference board and even a reference ECU that are available. I also don't think there is much of anything special about my schematic, you would recognize everything on it. The board has taken me a great deal of effort to layout and I'm not sure I want to see it being sold by other folks. On the other hand maybe that would work fine. So that's my pondering...

_________________
Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.


Top
 Profile  
Reply with quote  
 Post subject: Re: A locost EFI
PostPosted: September 30, 2015, 2:56 pm 
Offline
The voice of reason
User avatar

Joined: January 10, 2008, 4:47 pm
Posts: 7634
Location: Massachusetts
I need a little input on idle air controls. How many people expect that they would need this on their engine? Can team Slotus let me know how many pins are on their Idle Air Control connector or wether Ford 302 uses a stepper motor or solenoid?

_________________
Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.


Top
 Profile  
Reply with quote  
 Post subject: Re: A locost EFI
PostPosted: September 30, 2015, 3:12 pm 
Offline
User avatar

Joined: March 30, 2011, 7:18 am
Posts: 1553
Location: central Arkansas
GM typically uses a stepper. Ford generally uses a PWM-fed solenoid.

I'm not fond of the solenoid arrangement. The stepper moves, then stops. The solenoid requires current all the time to maintain position.

I guess from the ECM end, whatever is easiest to handle.


Top
 Profile  
Reply with quote  
 Post subject: Re: A locost EFI
PostPosted: September 30, 2015, 3:36 pm 
Offline
User avatar

Joined: March 17, 2015, 8:10 pm
Posts: 15
Location: Jersey City, NJ
mazda miata, dodge neon, honda accord - solenoids
dodge ram - stepper

_________________
DIY ECU project - http://rusefi.com/


Top
 Profile  
Reply with quote  
 Post subject: Re: A locost EFI
PostPosted: September 30, 2015, 9:57 pm 
Offline
User avatar

Joined: July 17, 2008, 9:11 am
Posts: 5173
Location: West Chicago,IL
Quote:
I need a little input on idle air controls. How many people expect that they would need this on their engine?
I am running the RX-7 BAC (a.k.a. IAC) valve with the megasquirt. If you want to increase idle for warm-up or run a constant idle speed for varying electrical loads (headlights, brake-lights, fan etc. ) you would want this option. I think most MS users who run on the road, use either the PWM or stepper mode.
It also opens the throttle a bit for starting purposes. It is not necessary to manually depress the throttle for starting or hold it open a bit while warming up. A very valuable option IMO.

_________________
Chuck.

“Any suspension will work if you don’t let it.” - Colin Chapman

Visit my ongoing MGB Rustoration log: over HERE

Or my Wankel powered Locost log : over HERE


Top
 Profile  
Reply with quote  
 Post subject: Re: A locost EFI
PostPosted: September 30, 2015, 10:33 pm 
Offline

Joined: May 9, 2009, 1:44 pm
Posts: 285
Location: northampton ma
Hi
As a megasquirt guy, I have taken the easy way,, use any solenoid vacuum valve with a 1/4 opening,,(fuel tank vent valve) simple to program open below a certain water temp. If the cold idle speed I too fast just restrict the hose to you liking,, can also adjust the cold spark timing.


Top
 Profile  
Reply with quote  
 Post subject: Re: A locost EFI
PostPosted: September 30, 2015, 11:38 pm 
Offline

Joined: February 8, 2014, 10:47 pm
Posts: 492
Location: Cornholio OR "Where the magic happens"
Both Ford and Bosch have 2 wire PWM IAC valves.

The Bosch has hose fittings, the Ford you need to make a block with hose fittings.

I have also seen a block with hose fittings made for the 4 wire stepper style IAC
http://www.diyautotune.com/catalog/custom-idle-air-control-body-for-use-with-jeep-40l-iac-valve-p-69.html

MS does PWM Idle by installing a mod to the FIdle output circuit
http://www.diyautotune.com/catalog/megasquirt-pwm-iac-valve-control-tip120-39modkit39-p-134.html

_________________
I don't know who I am, when I am somebody else.


Top
 Profile  
Reply with quote  
 Post subject: Re: A locost EFI
PostPosted: October 1, 2015, 12:59 am 
Offline
User avatar

Joined: August 11, 2013, 6:03 am
Posts: 441
Location: CNY
Hyundai Beta engines: push-pull PWM valve with hose barbs
90's to 2000's Mitsubishi I4/V6: stepper in throttlebody

_________________
Walt
06 RX-8 Shinka
91 3000GT VR4
01 Tibb
04 RX-8 Touring RIP
Some people never have anything except ideas. Go do it.
Emissions & fuel economy haven't exactly been areas of strength for past rotary power plants, but absolutely no one with a soul has ever cared.


Top
 Profile  
Reply with quote  
 Post subject: Re: A locost EFI
PostPosted: October 1, 2015, 8:57 am 
Offline
We are Slotus!
User avatar

Joined: October 6, 2009, 9:29 am
Posts: 7638
Location: Tallahassee, FL (The Center of the Known Universe)
horizenjob wrote:
Can team Slotus let me know how many pins are on their Idle Air Control connector or whether Ford 302 uses a stepper motor or solenoid?
Our tame Ford Mechanic, James Earl, says that "very old" 302s had stepper motors, but most of them used a solenoid. Mine, a 92 vintage, has a solenoid. Earl also says the IAC is a two-pin connector.
Edit:
Attachment:
IAC and 2-Wire.jpg
IAC and 2-Wire.jpg [ 888.07 KiB | Viewed 1867 times ]
Added a picture, because seeing is believing. Around here, sometimes smelling is believing, but let's not get into that right now. Note the two-wire connector.

:cheers:
Bubba

_________________
JD, father of Quinn, Son of a... Build Log
Quinn the Slotus:Ford 302 Powered, Mallock-Inspired, Tube Frame, Hillclimb Special
"Gonzo and friends: Last night must have been quite a night. Camelot moments, mechanical marvels, Rustoleum launches, flying squirrels, fru-fru tea cuppers, V8 envy, Ensure catch cans -- and it wasn't even a full moon." -- SeattleTom


Top
 Profile  
Reply with quote  
 Post subject: Re: A locost EFI
PostPosted: October 1, 2015, 2:42 pm 
Offline
The voice of reason
User avatar

Joined: January 10, 2008, 4:47 pm
Posts: 7634
Location: Massachusetts
Thanks JD. I had an '86 fox body so that explains my confusion about the stepper motor...

Impressively detailed painting job there, but I think the TPS needs paint too! It appears to be despondent and trying to escape.

From what I have heard here it seems reasonable to provide support for solenoid Idle Air Control and skip the stepper motor ones for my prototypes. Cars with carbs seem to do fine without them so they are probably not all that useful for a track car especially. I think on my car I'll go with a brass needle valve on the dash, that's something not everyone has.. :rofl: Kind of steam punk.

_________________
Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.


Top
 Profile  
Reply with quote  
 Post subject: Re: A locost EFI
PostPosted: October 8, 2015, 3:35 pm 
Offline
The voice of reason
User avatar

Joined: January 10, 2008, 4:47 pm
Posts: 7634
Location: Massachusetts
Quote:
Hi
As a megasquirt guy, I have taken the easy way,, use any solenoid vacuum valve with a 1/4 opening,,


Hi Rad, that's a good idea too. Wanna check out the new road course in Palmer next year?

It looks like the only case that might be hard for me is a V8 with individual coils and a stepper motor idle air control. We can put that off for future features. If anyone knows how much current these solenoid idle air thingies draw, please chime in. The unit I had seems to be AWOL at the moment.

The last couple of days I have been trying to tie up some loose ends, sort of literally. I had a big handful of unused pins on the CPU which have been ignored. That is something you should not do if the pins are inputs, so I was planning to turn them off or set them to be outputs in the code while it was booting. I'm having some second thoughts on this so now I am routing them out to resister packs which tie the signals to ground.

There is an advantage to doing this because it means you can get to these signals and modify the board to use them for other things. That's a help when you are getting started on a project and it turns out you forgot something and need to be able to get to it. It's taking me most of 2 days just to take take care of the first half of these though. An amazing amount of time coaxing various copper traces and other little bits a fraction of a milimeter at a time to make space for these other new little friends on the board.

Still hoping to get theses board designs sent to the PCB fabricator next week sometime. Anyone have any opinions on wether I should have just left those pins floating and set them to outputs during the boot. I think I had some fear that there might have been problems caused by that that might interfere with booting especially over the CAN bus. So trying to reduce risks, I guess.

_________________
Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 138 posts ]  Go to page Previous  1 ... 4, 5, 6, 7, 8, 9, 10  Next

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 1 guest


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

Search for:
Jump to:  
POWERED_BY