Early (1970t) EFI ITB Install Photos

[airfix4]

After a year+ hiatus from the subject project I'm back on the job. This forum, including but not limited to JPNOVAK and quaz, have been paramount in helping me to where I am now.

The 911 is a 1970 T with original 2.2. The Zeniths were replaced with Webers by PO.

The project ITB EFI. (I plan to do EDIS for the next project, but this is fuel only EFI)

All the hardware is procured/manufactured:
Megasquirt MS2,
DIYAutoTune wire harness
DIYAutoTune Power / Relay (not planning to use)
DIYAutoTune Stimulator
Suzuki gsxr (2001-2003) ITB
Weber intake manifold and stock linkage
Edelbrock Remote Sump
3d printed vacuum manifold


Software:
Turner Studio
Start Map (provided by quaz)

I am ready to wire the MS2 wiring and would like input and pictures of others installs. I could greatly use photos that show which where the MS2 wire harness plugs into the original 911 wires. It's not only a sanity check for me, but I'd also like to get advise on dos and don't of running the harness and mounting. I don't care how ugly your engine bay is, look at mine, but I'd like to see some that light a fire to clean mine up.

[Ferrino]

Cool stuff. I'm putting 2001 GSXR1000 TBs on my 3.2 and am currently at the intake manifold stage. Which injectors are you using in the TBs? I like the way you hooked the Weber linkage up to the TBs, although I'm going for a cable linkage myself.

[airfix4]

I'm using the stock gixxer injectors...should meet engine (2.2) demand and they are cheap with tons of them available.

Just realized this pic isn't to date...i'll shoot another. BRB...

[airfix4]

Originally Posted by airfix4

I'm using the stock gixxer injectors...should meet engine (2.2) demand and they are cheap with tons of them available.

Just realized this pic isn't to date...i'll shoot another. BRB...

[jdbunda]

Looking good! I am doing something similar with my 3.0 build, planning to ditch Webers for a Megasquirt based EFI with MFI ITBs (for that vintage look).

Fancy looking fuel rails - are those custom or from the Suzuki parts bin? Do the ITBs bolt right up to the Weber manifolds? What did you do for the crossbar?

Subscribed!

[Tippy]

Mine has consumed me, and I've figured out the easiest throttle hookup is using motorcycle throttle cables connected to trans bellcrank.

Venhill makes decent cables relatively cheap that will work.

[airfix4]

Originally Posted by jdbunda

Looking good! I am doing something similar with my 3.0 build, planning to ditch Webers for a Megasquirt based EFI with MFI ITBs (for that vintage look).

Fancy looking fuel rails - are those custom or from the Suzuki parts bin? Do the ITBs bolt right up to the Weber manifolds? What did you do for the crossbar?

Subscribed!

The fuel rails are off the shelf from summit, I think. Just extruded stock. You'll have to bore the dimensions for injectors as required (80mm centers i think).
The GSXR manifolds do not bolt right up to th Weber manifolds, but with a little work they should suffice.

I'm not sure what the "crossbar" is that you are referring to. The set up is using stock 1970 weber linkage.

[airfix4]

I decided to mock-up and test before cutting wires to length and and more importantly to me, doing something irreversible.

I invite comments, especially if I am doing something really not advisable.

I'm planning to run a base map provided by quaz, which I hope will get the tune close enough to dial in without an o2. If not, I'll have to add one of those too.

I also plan to upgrade to EDIS when this initial phase is stable.

The first image is an overview photo.



Next we have the MS relay board. Most choose not to use this and I don't disagree, however, I bought the thing as part of the procurement effort so I decided to use it.



Here is where I grabbed the power for everything. This has been unused since I owned the car. There is a wire attached on the right side of the photo, but no fuse or wire on the left side. I'm don't know yet if this supply will work and don't know how the previous owner wired. The car ran fine prior to this "upgrade" but there were certain electrical quirks (break/tail lights)...most of which I chalked up to grounding issues.





Here is the Edelbrock Sump (1970t does not have a fuel return line) I'm using. I choose to run the sump because I have put off this project for too long and was not making progress due to work and home projects. I plan to run a return line on next engine removal and remove the Edelbrock sump, but for now I hope this will get me running.

This is where I'm getting the tach signal for a fuel only, MS2.



Here is the TPS wiring:



And here is the grounds for the Edelbrock fuel pump and the MS relay board:

[timmy2]

Curious, is it recommended to use the negative side of the coil (grounded) for ms2 tach signal?
The blue yellow wire is the signal from the cdi.

[airfix4]

Originally Posted by timmy2

Curious, is it recommended to use the negative side of the coil (grounded) for ms2 tach signal?
The blue yellow wire is the signal from the cdi.

That is may assumption based on this, but I could very well be wrong.

[merlinfe]

Subsrcibed. I'd love to do this in the distant future.

[jpnovak]

WAIT!!!

If you have the stock CDI you can not trigger from the stock coil. It is a high voltage signal coming off the CDI and will fry multiple components inside your MS ECU. The coil trigger only works on a 12V kettering system.

YOU CAN. trigger of either the points wire or the black/purple tach wire on an early car.

[airfix4]

Originally Posted by jpnovak

WAIT!!!

If you have the stock CDI you can not trigger from the stock coil. It is a high voltage signal coming off the CDI and will fry multiple components inside your MS ECU. The coil trigger only works on a 12V kettering system.

YOU CAN. trigger of either the points wire or the black/purple tach wire on an early car.

Thank you sir, I'll see if I can find either of the tack inputs you recommend. If there is a locations I should look for that you recommend, I'd appreciate it. The car has a Perma-Tune box...i assume that is original on a 1970 but there seem to be a lot of variables in the early year cars.

[RD911T]

Subd

[jpnovak]

This picture shows a group of wires coming from your distributor. Do you have a Pertronix or points? What is signaling the Permatune?



Use the 12V square wave signal wire from your distributor to trigger the ECU. Make sure it is configured for a points-style standard trigger.

btw, use the ground post on the body in the upper left side of the engine bay. Ground everything EFI related at the same post. Generally the engine is not as well grounded as the body. floating grounds make signals have funny readings.

[airfix4]

I do have Pertronix. Thanks Jamie, I'll run out to the shop this morning and check it out.

Also thanks for grounding info. That is opposite of what I've seen in megasquirt videos, forums and instructions, albeit they were not 911 specific.

[jpnovak]

If you have the pertronix then just splice the signal wire and send this to the MS ECU. This is a 12V signal and will end up being split to the MS, CDI, and ECU all at the same time.

They key with grounding is to ground everything in the same place. If you ground in multiple places you will end up with ground loops. Pay attention to shielded wires and make sure they are only grounded on one end. Pay attention to grounded sensors. They ground through the sensor OR they ground through a wire. They should not ground in both places at the same time.

I prefer the body since that is closest to where the electronics (i.e. your relay panel) are mounted.

[airfix4]

Awesome, that will be easy.

Great info...The setup I'm running will only have tow ground run.
One is for the MS2 using the MS relay board.
The second ground is for the Edelbrock sump. I'm also using the relay from the MS relay board designated for the fuel pump to power the sump.

[airfix4]

Thanks again to Jamie for averting a catastrophic event.

I tied the tach signal into the same lead from the pertronix, black and purple wire.




I also relocated the grounds as recommended.

[jpnovak]

I admit I am having a hard time visualizing how you are going to connect the stock weber linkage to those ITBs. The geometry does not quite work out in terms of placement, bell crank arms and linkage rods.

maybe you are going to do something different that what is currently projected in the pictures.