Preparation for Electronic Fuel Injection conversion

While my car ran great, I am just NOT a big fan of CIS injection nor carbs. Call me "new school" but I understand the merits of technology and am not afraid to adapt it to the car.



The CIS K-Jetronic fuel injection is a "good" solution for stock cars. It's also pretty tunable for what it is. People have made lots of power through it and I'm not going to argue it's merits. What I AM going to argue is that it's cumbersome, heavy, and hard to work on in the car.

I also LOVE the sound of Carb'd 911's and will be working my way to getting that noise to come out of my car when I hit the gas pedal. That being said I did a bit of research and found some ways that others have modified their systems for EFI. Bitzracing is a good site for standard EFI conversions using the Megasquirt and I definitely will be using them as a reference, but I also wanted to do most of the work myself since I am going to go to full Individual Throttle Body setup on the car. I started by measuring and machining adapters to replace the factory mechanical fuel injectors with modern electronic fuel injectors. I will be using high impedance saturated style Domestic fuel inectors.

 

After machining and test fitting the adapters I started thinking about how I could make Individual throttles adapt to the manifolds. The original plan was to mill them down and then weld on tubes, but the more I thought about it the more I thought I could get the factory rubber sleeves to fit around the manifolds if I carefully cut them and fitted them up. This will be nice because it will: 1) Cost no money to do using stock components, 2) Allow for some misalignment of the injector bosses to the throttle body assembly and 3) Insulate from heat running up the throttle bodies thus keeping the air charge cooler. The problems I see now, are that the intake runners for cylinders 3 and 4 (same casting) are cast in a manner that they turn too quickly for me to be able to use them with the factory sleeves. I am currently sourcing two other 2.7L CIS manifolds from either cylinders: 1, 2, 5, or 6 to adapt in the same fashion I have below.