its a bespoke casting for the inlet manifold/plenum. The ecu is a rebadged 1800 8v from any astra/cavalier, as are the injectors 1800 8v injectors. The throttle body is of twin choke design found on the mk1 astra 1800 gte (18E). The airbox was bespoke cast aluminium base and bespoke airflow meter, but a 1600 one could be adapted to just have to alter the spring rate with the dial under the cover on top of the airflow meter, use 1600 airbox too.
The kit also included mounting brackets and fuel pump/regulator and filter assembly which was mounted just behind the front right hand wheel arch, so the fuel lines under the car didnt need replacing. You need an 1800 astra mk1 throttle cable too. (Its basically astra mk1 L jetronic injection system with bespoke inlet manifold to fit a 1300.
In a review in autocar in the 1980s it increased horsepower from 70 bhp to 83bhp compare to 87 with the sports carbs, but was a much more drivable car through the gears.
My friend and I have also adapted a 1600 injection system to run on a 1300 and its quite successful, no power figures because he sold the car soon after, it probably needed a bit more setting up, but was slightly faster, not much, but a lot smoother than a 1300 on a twin choke pierburg.
Alternator brackets have to be altered but you have already done that to fit the sport kit. Water hoses are also altered, either keep the setup you have on the sport or you can heat the throttle body with the coolant pipes from in line with heater matrix for cold weather.
It is very rare to get hold of a fuel pump assy from this kit. Just get hold of Nova GSi fuel pump, fuel tank and fuel lines and fit these to your car.
The ECU is a standard vauxhall/opel Bosch 1800 8v ecu, the kit was originally fitted with the standard cam but irmscher did a fast road cam as used in the Sport. Superchips have an upgrade for the Corsa Sprint as do FSE do a specific boost valve. Under "Opel Corsa 1.3i (irmscher)". I dont like Superchips ( i have a both standard and Superchip modified ecus for the system) I would recommend Unichip. There is no real reason to fiddle with ECU id save you money. The ecu sits under the dash behind the bulkhead grommet just like in an astra.
Yes youll miss the growl, but it picks up better in gear. The ecu sits under the dash. The engine loom is designed to plug into the original loom as engine bay all the opel/vauxhall looms are modular, but it needs modifying as it is designed for a left hand drive car. Nothing you wont be able to manage it just needs the insulation tape cutting off and laying out again for right hand drive while extending the battery12v feed and coil feeds.