Throttle Body / EFI project

Mike Bonkalski · 06-09-2005, 11:30 AM

My little rolling science fair experiment is getting closer to being fired up again. I decided to take the winter and install some throttle bodies and go EFI. That lead to running new fuel lines, new fuel pump, distributorless ignition, etc... Well it's taken a bit longer than expected and it's killing me since the weather is nice.

This is where I am at now, installing the TWM 3003 46mm throttle bodies w/ Boxster injectors. The fit is great and they mate up real well with the weber linkage although I may have to make the drop links a bit shorter to improve the geometry.

These things are sweet, the fit and finish is excellent. All I have left is to port the manifolds and mount the fuel rails.

All of the wiring is done with the Motomotions Megasquirt color-coded harness and will run to the relay board installed in the engine bay.

Hopefully the engine goes in this weekend.

Thanks to Dave at TRE for a trick way to run the fuel lines for a clean look.

Kemo · 06-09-2005, 11:36 AM

looks great...dont forget to post after you get the fuel rails mounted. How much $$$ for the Boxter injectors?

rfuerst911sc · 06-09-2005, 12:44 PM

Looks nice what size motor? What upgrades to the engine if any? You are running a Megasquirt ECU? Details man details!!!

Mike Bonkalski · 06-09-2005, 02:02 PM

The motor is a 2.7 (euro pistons), single plug with solex cams. It used to have webers and was a sweet running motor, but I thought it was time for a change to modern technology. I wanted something that will allow flexibility in case I ever want to run wild cams or high compression pistons. I expect the throttle response to be as good as or better than the webers. I don't necessarily expect much of a performance upgrade, but the ability to dial in the motor will be priceless.

I will run Megasquirt with the Megasquirt-n-Spark software until the MSII upgrade is available at the end of the summer. It is a simple upgrade to the current unit and under $100. I am also controlling spark with the EDIS unit. That way if I ever twin plug in the future all I need to do is run and additional coil pack in parallel. Its accurate to 9000 rpm, has a limp home mode if any componants fail, and is/was mass produced, so parts are inexpensive. My initial concern was plug wires, but I had the same company that makes wires for Clewett make up some special EDIS/Beru plug wires for me.

I also have the bungs welded in the exhaust to run a dual channel wide band O2 sensor. This should help immensely with tuning. Souk and I also have some dyno time planned for later in the summer just to dial every thing in perfectly.

More details will follow as I get this motor started. I will detail the tuning process and document it here on the board so others interested in this type of project can have some useful info to digest.

rfuerst911sc · 06-09-2005, 02:19 PM

Thanks for the details. I have had a few email conversations with you regarding this setup and am interested in the final results, this may be next winters project.Nice work.

Bill Verburg · Bill Verburg's Garage

Very nice, I would love to do something like that w/ DTA or Motec instead of trying to decipher Motronic's hieroglyphics

Shaun @ Tru6 · 06-09-2005, 03:09 PM

Quote:

Originally posted by Bill Verburg
Very nice, I would love to do something like that w/ DTA or Motec instead of trying to decipher Motronic's hieroglyphics

the shop I use, Rensport, is close to finalizing a DTA kit that will allow you run wild cams on a 3.2 that will both idle nicely and pass emissions.

René had a good day at the dyno a week or 2 ago I believe.

ssetek · 06-09-2005, 03:30 PM

Quote:

Originally posted by Shaun 84 Targa
the shop I use, Rensport, is close to finalizing a DTA kit that will allow you run wild cams on a 3.2 that will both idle nicely and pass emissions.

René had a good day at the dyno a week or 2 ago I believe.

wild cams and a smooth idle comes from running a alpha-n/speed density blended system works well with throttle bodies also due to poor vac refernce from the tb's and fluctuating map signal from wild cams, motec dta fast autronic all are capable of theis nice option,

hows the spark control setup on the ms system work? have you tried it yet??

Mike Bonkalski · 06-09-2005, 03:52 PM

The megasquirt can control spark in a few different ways, but I chose to use the distributorless Ford, yes Ford EDIS setup. It uses a VR (variable reluctance) sensor and a 36-1 notched wheel for timing. The Ford VR sensor can fit inside of an Electromotive like sensor holder and the notched wheel attaches to the back of the crank pulley. For the EDIS-6 system, the VR sensor needs to be 60 degrees or 6 teeth BTDC when the notch is set at TDC. It is in the perfect position with the Electromotive holder.

The sensor signal is run to the control module, which is linked to the megasquirt, and the module fires the coil based on the pararmeters set up in the megasquirt software. You have a spark map and enter rpm/MAP specific advance/retard values. It has a limp home mode where it sets the time to 10 degrees advance if any componant fails. We had a guy at the shop the other day who is running this setup with TBitz's CIS/EFI kit. It is supposed to be accurate to 9000 rpm and quite durable. Ford used the system on their vehicles for 10+ years.

I am a bit concerned trying to tune spark and fuel at the same time. So I may just take standard 911 spark advance values and extrapolate them through the RPM range to get the fuel right then dial in the spark.

Megasquirt allows for a blended alpha-n/speed density program to help with the fluctuating MAP signal. I am also running the vaccum lines to a common plenum, then to the megasquirt, which should also help settle the signal a bit.

Jay Auskin · 06-09-2005, 04:04 PM

Lookin' good Mike! I can't wait to hear that thing fired up!

TimT · 06-09-2005, 04:05 PM

Quote:

I am a bit concerned trying to tune spark and fuel at the same time. So I may just take standard 911 spark advance values and extrapolate them through the RPM range to get the fuel right then dial in the spark.

That is the correct methodilogy to tune an EFI system.
First get the fuel set so you have safe a/f and egt in all operating ranges, then you can tweak the timing to extract max power.

Typically this is done on a dyno, you adjust timing until knock is sensed or heard, then you back the tiing off a few degrees for safety.

After you have your fuel and spark "optimised" you can go through the cycle again and refine your settings, and adjust accel enrichment etc..

ssetek · 06-09-2005, 10:32 PM

Quote:

Originally posted by TimT
Typically this is done on a dyno, you adjust timing until knock is sensed or heard, then you back the tiing off a few degrees for safety.

by the time you actually hear knock its way past BMEP, look for a diminishing return of torque feedback from the dyno from the advance given to the engine than you are getting close to BMEP and peak torque is at BMEP so back a little off once reached

what is the cost of a full spark and fuel control ms system run.

i might be interested in one to try it out on some thing to see what its capable of ..

JohnJL · 06-10-2005, 02:32 AM

I'm just starting out on the same project on my 3.0.

Can you post some close-ups of the EDIS attachment and spart setup?

Thanks!
John

CindyDuck · 06-10-2005, 02:48 AM

With individual T/Bs is fuel rate controled by throttle position only? There seems to be no way of measuring MAF or intake vaccume, I would imagine emission would play a part with the wide ban O2 sensor.Man they look sweet, I bet they are pricey.
Mike

eimkeith · 06-10-2005, 03:24 AM

Are there prior threads for this EFI build? I'd like more information on the individual components, etc...

I was looking really hard at my MFI throttle bodies and thinking the same thing...

Mike Bonkalski · 06-10-2005, 03:28 AM

There are vacuum ports cast into each individual intake and they connected at one output at the center throttle body. I will take each vacuum line and run them to a small manifold to smooth out the signal. Then connect the ECU MAP input to the manifold.

The system I put together is not wildly expensive or cheap either. The full package I am installing cost the same as a set of PMO's. Since I was able to sell the webers I already had installed, the project, measured against EFI conversion standards, was inexpensive.

Mike Bonkalski · 06-10-2005, 03:32 AM

Keith,

There are a few theads over on the gruppe B board showing some of my installation of componants, but this is the first time I posted this project on Pelican.

The most difficult part of the project so far has been running new Aeroquip socketless fuel lines through the tunnel. The rest has been straight forward and simple. If you can solder and turn a wrench, you can do this.

914timo · 06-10-2005, 04:49 AM

Quote:

I was looking really hard at my MFI throttle bodies and thinking the same thing...

Heh, look what I have been thinking about..... here

Mike, really good looking engine. I like the idea of using MS&S too. Have you the 36-1 ring ??

Mike Bonkalski · 06-10-2005, 06:49 AM

I thought about MFI throttle bodies or even Suzuki GSXR throttle bodies, but I was concerned about setting up the linkage. It would be really slick if you can get it to work and I will be following you progress.

If anyone wants some GSXR throttle bodies to play with, let me know. I have 8 of them looking for a home.

Mike Bonkalski · 06-10-2005, 07:13 AM

Here are a few more pictures...

Crank pulley w/ 36-1 toothed wheel - VR Sensor - Sensor Mount. I had to shave the case a bit to allow enough room for the toothed wheel

ECU - Relay Board - Wiring Harness

Mounted Relay Board

Mounted Coil Pack

Mounted EDIS Ignition Controller