79+80_rx-7

From my understanding, it can be done

I need to rebuild my 12a some day anyways...



Lets see if this combo would work.


Lower RB Dellorto 12a manifold.
89+ N/A manifold and all EFI system (minus ecu)
Mega squirt ECU
All sensors for the EFI from the 89+ motor
Rebuild the 12a with a center plate with and injector bung


Would it work???

Kenku

Sounds pretty workable to me. I'm working on scraping together the money to try a more homebuilt approach to manifolds and stuff...

79+80_rx-7

any one else?

Suggestions comments and opinions welcomed...



please????

Pele

iTrader: (28)

Provided enough money, anything is possible.

By far, the simplest method of making an EFI 12A is to use everything stock with a TBI setup.

Think about it. the first EFI vehicles were just carbureted vehicles minus the carb, slap on a few injectors on the same manifold, add o2 sensor and TPS, and you're set.

The hardest part would be programming the ECU, I'd think.

Logo

If you have more money in your budget I believe you can use a weber 12a manifold with a twm setup.

moremazda

iTrader: (4)

NO!! The 89 has a different port and bolt pattern. You can use the 12a lower with a GSL-SE upper. Although you might see a larger amount of power with a down draft or side draft style throtle body.

Ryan

MIKE-P-28

iTrader: (1)

Wasnt there a guy that put VW fuel injection on a rotary once?

The VW fuel injection on some older Audi's, VW rabbits , Golf's etc.. Use magnetic fuel injection, NO ECU

jr69187

Yup mike is right. I think that is the easiest way find out what it was on and i might be able to find one at the local junk yeard they have alot of older audis like a 5000s it may have it.

jr

Directfreak

iTrader: (2)

You Mean This thread here?

Manntis

er... I believe it's mechanical fuel injection. Bosch type, specifically. There's a disc-shaped air flow valve that senses how much air the engine is drawing in, then a volume of fuel is sent to the injectors based on air consumption.

It's a simple system, and because of those lunatic "sudden acceleration" stories aired by irresponsible 60 Minutes reporters you can pick up a complete Audi 4000 or 5000 (both have the system) for cheap.

Only thing is, it's designed for a 5 cyl car, not a 2 rotor, so there's work to be done...

Pele

iTrader: (28)

WOAH!!! That looks like some kinda freakish nightmare...

It seems cool though.

Wonder what the gains are like...

So the GSL-SE upper will fit on the 12A lower... Nice... And the injectors fit right in?

How does the adaptation from 4 banger to 2 rotor go?

error402

That is the link and images I was looking for ealier in another thread.

Thanks

-Error402

12aPwr

if im not mistakin isnt that the cis injection, i agree with manntis there would be some work to have it set for 2 rotor becouse they where in 5cyl audi's like the quattro's and others

Kenku

Yeah, but they were also in 4-bangers like the VW Rabbit. I know this because we had quite a few around, and I was going to adapt one of the systems over... until I decided that there's all sorts of downsides to mechanical fuel injection and stuff.

moremazda

iTrader: (4)

YUP!!

Only if you rebuild the motor with a GSL-SE center plate. THe GSL-SE used only two injectors. If you were to do this you would have to come up with a way to mount the injectors in the manifold.

Ryan

79+80_rx-7

do the runners line up using an 89+ one???


If it does, then cant i just make my own flanges, like PJ would??





Well.... What center plate would I have to use for the 89+ intake to work???


I was thinking TII center plate!!!....


Thanx, Laterz, Andrew

MIKE-P-28

iTrader: (1)

Theres 2 audi 5000's at the local liberty u pull it, the cars are almost completely in tact, no one has touched **** underhood, wish i knew what VW parts were fast novers, Id take some parts at next to nothing, and sell em on ebay

fatboy7

Doesn't the TII rotor and side housings have the water seal on opposite housings vs. pre-86' 13B's? If so, you can't use the TII ceter plate... that's of course if I heard correctly.

fatboy7

<double post>

79+80_rx-7

oh ok... THANX!!!



Laterz, Andrew


When the time comes to rebuild my motor, (not very far away) I will try this!!!!

Bruceman

iTrader: (5)

Pictures of the Rx-7 12A with CIS Injection are mine.

This is the first stage of my turbo installation.
The CIS is off an Audi 5000 Turbo. The air flow for the 12A and the 5cyl Audi are very close. I really wanted 5 injectors - 2 injectors per rotor plus a 5th. I also have the cold start injector mounted in the dynamic chamber in case I need extra fuel for cold starts or max boost.
It certainly has the ability to deliver way to much fuel as evidenced by the black smoke when accelerating hard.

This setup has been running well. Currently have the Dellortos back on as the CIS fuel pump has been acting up. I bought it used. Waiting on new pump to arrive.

Since installing I have learn a lot about changing the fuel mixtures by making the warmup regulator adjustable and adding/removing shims in the main pressure relief valve.

With the Dellorto back on I really notice how the CIS system is superior in cold weather and in the low rpm acceleration. Don't notice much difference in the top end.
Although the CIS doesn't have the fabulous Dellorto induction sound!

Once I have this injection sorted out I'll be bolting on the turbo.

Bruceman

79+80_rx-7

but wouldnt it be easier to tune with a stand alone ECU?? Like a Mega-Squirt?!?!?


I would think so...


so someone tell me this...


EFI, or MFI (the audi way, isnt it mechanical??)


Thanx, LAterz, Andrew

Manntis

Fuel Injection has been around since the 50's, just reserved for high end cars until the 80's. Of course, for the first few decades it had to be mechanical, as the transistors to make a small circuit board didn't exist then.

Computer controlled fuel injection is the most efficient, but even the EGI systems on older 13Bs are pretty simple.

Bruceman

iTrader: (5)

If you have the $$$ EFI is the way to go.
Check out:
http://www.twminduction.com//Home/Home-FR.html

They have a manifold for a 12A ($500), throttle bodies($300 each), fuel rail kit($150), and injectors. Add a controller and you're probably talking $3000.

An endless flow of cash would be fun!