910 Megasquirt - LotusTalk - The Lotus Cars Community
 4Likes
Reply
 
LinkBack Thread Tools Display Modes
post #1 of 52 (permalink) Old 12-02-2015, 11:10 AM Thread Starter
Dreaded Prior Owner
 
snowrx's Avatar
 
Join Date: Oct 2011
Location: Far from another Esprit.....
Posts: 646
910 Megasquirt

In answer to Delomike1049 query:
"Would love to see some pictures of the EFI installation, and some more info on how you did it."
I'll attempt a brief overview of my EFI and I guess test the limits of forum photo attachments.

I built a MS3 Megasquirt from a kit at DIYAutoTune.com with the MS3X option. Get their long wiring harnesses as well, pricy but worth the time saved and having the color coded wires.

MS3X daughterboard allows you to go sequential injection, but also adds lots more input/outputs. A batch fire install without it would be a simpler/cheaper option.

You will need a crank speed input. A Variable Reluctance sensor from a Ford V6 worked for me. Not much room at the crank pulley, my current setup is a 3/16" thick 36-2 wheel pinned and epoxied to a step cut into the back of the crank pulley, and a short stiff mount for the sensor. Fabricating the custom wheel is a post in itself, but simple to do.

If you want to go sequential, you'll need a cam sensor. Another VR sensor mounted behind the exhaust cam pulley reading a M6 pin placed in a spoke. I ended up having to mod the sensor to get room for the cable connector with the motor installed, it's tight to the sidewall in my G-Turbo.

Not sure what I can get away with for attachments on the forum. I'll stop now.
Attached Images
         

1985 BRG Turbo Esprit
Chargecooled w/Megasquirt EFI
snowrx is offline  
Sponsored Links
Advertisement
 
post #2 of 52 (permalink) Old 12-02-2015, 11:30 AM
Registered User
 
Join Date: Feb 2009
Location: Rochester, NY
Posts: 895
I did MS2 on my DeLorean a few years back. Fuel control only, no ignition. Any pictures of how the fuel rail is set up?

2016 Chevy Cruze, manual
1987 Lotus Esprit Turbo HCi
2005 Elise
1981 DeLorean, manual, EFI conversion
delomike1049 is offline  
post #3 of 52 (permalink) Old 12-02-2015, 11:42 AM Thread Starter
Dreaded Prior Owner
 
snowrx's Avatar
 
Join Date: Oct 2011
Location: Far from another Esprit.....
Posts: 646
I had the carb turbo, so no throttle bodies available. I also knew I wanted to delete the vacuum pump and belt in the lighter/simpler interest, so I went with a plenum style manifold I could pull vacuum from. Fabrication of that is also a post in itself and my first TIG project, so don't look too close. The plenum is an old medical oxygen bottle. The layout may change in the future to adopt an intercooler. I tapped the coolant passage in the intake for a GM CLT sensor, and added a MAT sensor behind the Throttle Body.

A 58mm GM TB with integral TPS sensor and Idle air control also had some vacuum/MAP ports built in. Relocating the TB meant I had to run a longer throttle cable to the new location.

Lotus had bosses for injectors on the intake manifold from way back, so it was easy to drill and hone it for some injectors. The fuel rail is some chrysler junkyard piece that mostly matched my runner dimensions, sectioned, welded and powder coated in my toaster oven. If you are converting from carbs, you will need to add a high pressure fuel pump, fuel lines and a pressure regulator for the injectors.
Attached Images
       

1985 BRG Turbo Esprit
Chargecooled w/Megasquirt EFI
snowrx is offline  
 
post #4 of 52 (permalink) Old 12-02-2015, 12:17 PM Thread Starter
Dreaded Prior Owner
 
snowrx's Avatar
 
Join Date: Oct 2011
Location: Far from another Esprit.....
Posts: 646
This was all about safety, so the distributor had to go away from under the fuel area. A simple machined plug fills up the hole where it used to hide from servicing.

The MS3X allows control of logic coils, so 4 GM LSx series coils (eBay) moved to above the drivers side gas tank, and I made up some new plug wires to suit.

The injectors I had left over from an old project were low impedance peak & hold style so I had to add a kit box for that. Lousy picture, I should stop fabricating and clean my quarter windows.

The new injectors,coils, boxes & sensors etc. will need power, so I threw an old fuse box in. I should add a relay socket block and clean up some wiring connectors before it's done. The MS3 controls the fuel pump relay also so you'll need to run a wire to it. I retained the inertia switch inline for rollover protection, although the MS3 will shut off pump power if it loses RPM signal.

A wideband O2 sensor is essential for tuning and closed loop operation so you'll need a bung on your exhaust. Some say it should be farther down the exhaust stream, but it's holding up so far where it is.
Attached Images
     

1985 BRG Turbo Esprit
Chargecooled w/Megasquirt EFI

Last edited by snowrx; 12-02-2015 at 01:10 PM. Reason: clarity
snowrx is offline  
post #5 of 52 (permalink) Old 12-02-2015, 12:39 PM Thread Starter
Dreaded Prior Owner
 
snowrx's Avatar
 
Join Date: Oct 2011
Location: Far from another Esprit.....
Posts: 646
The rest is all wiring and tuning. If you choose to add all the MS3X options, your wiring harness might be 1.5" thick like mine, but a simpler MS2/MS3 install looks pretty straightforward.

I pulled timing specs off the interwebs for the stock distributor, and most of the fuel table can be populated with the auto-tune function of Tuner Studio software using the feedback from the O2 sensor.

Getting the idle air control, boost control, warm up enrichment tuned etc is time consuming iterative work I'm not qualified to direct or advise on. Suffice to say I was able to get it to where I was happy with it by using the excellent support of the Megasquirt forum members.

The tuning potential is stupefying. Boost by gear/data logging/knock control/failsafes/digital dashboards/idle speed control/tune by cylinder/VSS inputs/CAN bus support etc. is all available once the basics are in place.

My intent was to improve starting, drivability and hopefully fuel mileage with modern engine managment. The number of engine fires from the dizzy under pressurized carbs gave me added incentive. I'm limited in the pursuit of power by my Citroen transaxle, so I'm not planning on big power.

1985 BRG Turbo Esprit
Chargecooled w/Megasquirt EFI

Last edited by snowrx; 12-02-2015 at 12:52 PM.
snowrx is offline  
post #6 of 52 (permalink) Old 12-03-2015, 04:01 AM
You can't make this up
 
Jenna'sEspritTurbo's Avatar
 
Join Date: Oct 2015
Location: Milford NJ
Posts: 1,157
Wow very nice job indeed. I would be happy just to get Penelope back to 100% of which I am well on my way. Now on the other hand Mike has lots of time on his hands with his car now in storage. Time to pull her out and get to work Mike. I don't think I would attempt that on my own,, not ever. Good job.
Jenna'sEspritTurbo is offline  
post #7 of 52 (permalink) Old 12-03-2015, 09:19 AM Thread Starter
Dreaded Prior Owner
 
snowrx's Avatar
 
Join Date: Oct 2011
Location: Far from another Esprit.....
Posts: 646
Well, I'm impressed with your relentless progress on Penelope. Good job yourself!
I tend to do more planning, purchasing and procrastinating than actual work. Of course it is close to freezing in the garage right now, where the engine hangs on the hoist awaiting reassembly...
snowrx is offline  
post #8 of 52 (permalink) Old 12-03-2015, 11:01 AM
Registered User
 
Join Date: Dec 2013
Posts: 3
Hi Snowrx,

i have already done the same MS3X conversion to my Turbo 1983.
Nice solution with the cam sensor!!
Which twin scroll turbo is in your car?
How does it spoll?

Regards Harald,
lotushiast is offline  
post #9 of 52 (permalink) Old 12-04-2015, 11:03 AM Thread Starter
Dreaded Prior Owner
 
snowrx's Avatar
 
Join Date: Oct 2011
Location: Far from another Esprit.....
Posts: 646
Hi Harald, you sent me a 910 tune long ago, Thanks.
My turbo is a Borg Warner EFR 6258 with a low boost wastegate capsule. I wanted to maintain the exhaust separation to the turbine for faster spooling, and went with the smallest model for drive-ability on the road.
I don't have any data to compare the Lotus original vs the EFR, but it seems to work as well or better, with 10psi boost (~170kpa) at or before 3000 rpm. This scatterplot is with the boost control set for 160kpa, the curve at upper left shows boost response with my current setup, but I was not able to finish tuning the table, I blew a head gasket. I'm hoping I can smooth out the higher rpms of the curve a bit.
Attached Images
 
Attached Images
File Type: pdf efr_technical_data.pdf (499.1 KB, 113 views)

1985 BRG Turbo Esprit
Chargecooled w/Megasquirt EFI

Last edited by snowrx; 12-04-2015 at 11:49 AM.
snowrx is offline  
post #10 of 52 (permalink) Old 02-03-2016, 04:05 PM Thread Starter
Dreaded Prior Owner
 
snowrx's Avatar
 
Join Date: Oct 2011
Location: Far from another Esprit.....
Posts: 646
EFI Manifold ver 2.0

Well, after datalogging some v. high intake air temps it's time to look at a charge cooler. Looking towards practical packaging over outright performance and minding my fabrication limits, this is what I came up with to test next.

I wanted to avoid the "hot" side of the engine bay, fit under the engine cover, be no wider than my existing manifold, and retain engine service access if I could. To fit an inexpensive 4.5" charge cooler core, I needed to tilt the intake runners down 22 degrees and lay the core on top of them. To smooth the 180 turn from the core to the runners I added a generous radius to the bottom of the plenum joining the two. I don't have a pic of the final runner entrance contours. I did my best to blend the runner and plenum floors and build up the best funnel radii I could between the runners and walls. Not much you can do on the inside turn from the core to the tops of the runners, but the flow is spread over 45 square inches exiting the core so hopefully that helps with lower velocity/losses.

In retrospect, I wish I had spent more time looking for a longer core so I could spread the runner bores more to allow better entry. But with the 10" long plenum box, I can access the timing marks and under the plenum better. Hey, if I still had a distributor, I could reach it now!
Attached Images
         

1985 BRG Turbo Esprit
Chargecooled w/Megasquirt EFI

Last edited by snowrx; 02-04-2016 at 07:22 AM.
snowrx is offline  
post #11 of 52 (permalink) Old 02-03-2016, 04:22 PM Thread Starter
Dreaded Prior Owner
 
snowrx's Avatar
 
Join Date: Oct 2011
Location: Far from another Esprit.....
Posts: 646
Again, packaging over performance here. The port runners are now about 1.4 inches longer than the original carb intake length, and the 1.75" ID port runners are probably too big for good velocity, but at least they should provide plenty of flow for the turbo to make up for the sub optimal dimensions. With the small area change and lack of a sharp cutoff at the runner entrance, I wonder if a decent pulse would be generated anyway. It seemed to me the original port length was probably on the third or fourth harmonic anyway for normal driving rpms.

The post-core plenum volume is just less than the engine displacement, and I have to wonder if the free flowing core or the volume behind the throttle body will help transitional air supply or if it will be limited by the core face.

Still a few braces and nipples to add before I find out if this lump will truly clear the engine cover! Of course the EFI harness will have to be re-worked for the relocated sensors.
Attached Images
   

1985 BRG Turbo Esprit
Chargecooled w/Megasquirt EFI

Last edited by snowrx; 02-06-2016 at 08:13 AM.
snowrx is offline  
post #12 of 52 (permalink) Old 02-04-2016, 06:48 AM
Registered User
 
Join Date: Mar 2010
Location: Minneapolis, MN
Posts: 383
Looking good! I love following fabrication projects.
shill68 is offline  
post #13 of 52 (permalink) Old 02-04-2016, 07:54 AM Thread Starter
Dreaded Prior Owner
 
snowrx's Avatar
 
Join Date: Oct 2011
Location: Far from another Esprit.....
Posts: 646
More Fabrication then-

Started with a $99 eBay 4.5" x 4.5" x 10" core intercooler, some tube and plate. If I did it again I would use 3/8" or thicker plate for the flange, but my tiny TIG machine is maxing out trying to heat thick sections in my cold garage, and I used 1/4", which warped and required surfacing after. Rough full scale drawings help with confirming fits and angles.

Table saw sled with a metal cutting blade made nice straight cuts to remove the offside tank.

I did not need the full 3" diameter of the cooler entrance, so the throttle body plate bores are offset slightly down for more clearance. Machining a step into the plate helped with the welding alignment and penetration later. A rubbed paper template saves a lot of layout measurement.

Some temporary braces and clamping pliers held the runner plate in place for tube fitting.
Attached Images
       

1985 BRG Turbo Esprit
Chargecooled w/Megasquirt EFI

Last edited by snowrx; 02-04-2016 at 08:00 AM.
snowrx is offline  
post #14 of 52 (permalink) Old 02-18-2016, 09:50 AM Thread Starter
Dreaded Prior Owner
 
snowrx's Avatar
 
Join Date: Oct 2011
Location: Far from another Esprit.....
Posts: 646
Added a MRDANGERUS style knock sensor boss to my block in the location later cars had it mounted. Whatever the acoustic properties of epoxy might be, it's got to be quieter than my old aux housing bolt mounting.
Attached Images
 

1985 BRG Turbo Esprit
Chargecooled w/Megasquirt EFI
snowrx is offline  
post #15 of 52 (permalink) Old 02-18-2016, 11:29 AM
Registered User
 
Join Date: Feb 2009
Location: Rochester, NY
Posts: 895
One thing that has always made me raise an eyebrow about the EFI esprits is that the injector nozzle is quite a distance from the intake valves. Doesn't seem optimal to me, but apparently it works just fine anyway

2016 Chevy Cruze, manual
1987 Lotus Esprit Turbo HCi
2005 Elise
1981 DeLorean, manual, EFI conversion
delomike1049 is offline  
post #16 of 52 (permalink) Old 02-18-2016, 11:40 AM Thread Starter
Dreaded Prior Owner
 
snowrx's Avatar
 
Join Date: Oct 2011
Location: Far from another Esprit.....
Posts: 646
There's also the issue of aiming one injector at the port divider, which assures some wall wetting, but it's a step up from a whole ports worth of carburetor spray.

sailorbob was looking into twin cone injectors that could hit both valves, but I'm not at that level of tuning by a long shot.

1985 BRG Turbo Esprit
Chargecooled w/Megasquirt EFI

Last edited by snowrx; 02-18-2016 at 11:50 AM.
snowrx is offline  
post #17 of 52 (permalink) Old 02-19-2016, 11:05 AM
Registered User
 
Join Date: Dec 2013
Posts: 3
Hello Snowrx,

want to ask you how much is your manifold kpa at idle with your single throttle ?
at my car i achieve around 65kpa at idle with itb's.

Thanks Harald.
mieczkow likes this.
lotushiast is offline  
post #18 of 52 (permalink) Old 02-19-2016, 11:26 AM
Registered User
 
cyow5's Avatar
 
Join Date: Mar 2013
Location: NoVa
Posts: 3,879
Quote:
Originally Posted by lotushiast View Post
Hello Snowrx,



want to ask you how much is your manifold kpa at idle with your single throttle ?

at my car i achieve around 65kpa at idle with itb's.



Thanks Harald.

Post #9 shows his pressures so it looks about the same. Whether ITB or single TB, the pressures should be close for the same idle speed on the same motor


Sent from AutoGuide.com Free App

"Lots Of Trouble; Usually Serious"
cyow5 is offline  
post #19 of 52 (permalink) Old 02-20-2016, 05:49 PM Thread Starter
Dreaded Prior Owner
 
snowrx's Avatar
 
Join Date: Oct 2011
Location: Far from another Esprit.....
Posts: 646
When I'm looking at the VE and spark tables, I usually see 40-45 kpa, but as cyow5 pointed out the graph is showing 52 or more. I'll look at some other datalogs and see if they agree with the one I posted or try to figure out the discrepancy.

It will be awhile before I test with the new manifold, .7 m of snow outside right now!

1985 BRG Turbo Esprit
Chargecooled w/Megasquirt EFI
snowrx is offline  
post #20 of 52 (permalink) Old 03-02-2016, 06:25 PM Thread Starter
Dreaded Prior Owner
 
snowrx's Avatar
 
Join Date: Oct 2011
Location: Far from another Esprit.....
Posts: 646
Harald, After looking at a few logs, it looks like I'm idling between 45 and 55 kPa, average about 47. Engine just broken in with fresh pistons and valve work.
Attached Images
   

1985 BRG Turbo Esprit
Chargecooled w/Megasquirt EFI
snowrx is offline  
Sponsored Links
Advertisement
 
Reply

  LotusTalk - The Lotus Cars Community > Lotus Discussions > Lotus Esprit

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the LotusTalk - The Lotus Cars Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome