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I bought a Porsche 928 från 1982 a few years ago and I use it as my regular car. I drive it in the summer and in the winter and snow. It's actually a perfect winter car. It's even equipped with a tow bar! Now thats unusual for a Porsche!! I've got a roof rack as well. I joined Porsche Club Schweden PCS. I've had it for four almost trouble free years.

It used to comsume some oil and when the water pump started leaking I decided to change the waterpump, cam belt and valve stem seals at the same time.
To remove all things surrounding the waterpump and camshafts was a piece of cake. The problems started when I tried to lift the camshaft and its housing from the cylinder heads, especially on the right hand side. There is a pipe for the air conditioning which runs along the housing and it was really in the way. I managed to lower the pipe to get just enough space to remove the camshaft and its housing. If you do attempt this at home remember that the lifters are loose in the housing and they may fall out if you're not carefull. To change the valve stem seals was not really a problem. A few home made tools and using air pressure to keep the valves in position made the job easier.
The hardest thing of all was to lift the camshaft housings in place again. You have to controll eight lifters, the new gaskets which you didn't want to brake, very limited space and taking car not to bend or puncture the pipe for the air conditioning. It wasn't easy but I made it and the car runs beautifully. I don't have to fill oil every time I fill petrol.
I will not say anyting about changing water pump and cambelt because compared to lifting the camshafts and their housings that's childs play.

I had the camera with me when I did the job and I took these pictures.

I used the pictures at www.928intl.com when I was bying the gaskets and stem seals. There are really good pictures on almost all components in a Porsche 928. If you have a 928 I can strongly recommend a visit. I also found this picture of this race 928. It's quite cool.

I can also recommend a visit to the 928s4vr homepage if you are interrested in Porsche 928s.

Transformation!
The early 928's are eqiupped with Bosch K-jetronic. It's was working quite alright but after 230000kms it was starting to get worn and parts are expensive. We had to do something about that so why not convert it into electronic fuel injection?

The conversion team is myself, Klotzakk and Lars. Klotzakk is the wiser one, with a liking for german cars and equipment (read Mercedes and Bosch). He is also quite good at electronics which can come in handy! Lars is the computer wizard. He has a particular liking for german supercharged cars (read beetle with a huge turbo charger). And then there's myself, in this case I was just supplying the car to be modified.

I think it was Lars who found MegaSquirt (MS) on the internet and thought that it would be neat to use it in his beetle. Carburettors and turbo chargers can be tricky to match. Klotzakk got involved and he had a look at the drawings shown on MS's webpage and said it would work. We started to discuss which car we could most easily convert. We had two choices, the Golf GTI or the Porsche 928. The injectors in the Golf are actually situated in the cylinder head which would make it more difficult to fit the electronic injectors which are much bigger in diameter. The Porsche injectors are situated in the runners and are easier to remove and to modify. The desicion was taken to convert the Porsche! It coincided with myself working abroad for a long time so we didn't have to work under pressure.

Klotzakk started to rip out all the stuff belonging to the k-jetronic and the intake manifold. When everything was out it was a grim sight! It had been leaking both oil and water. In the box are some details going back after being cleaned.


As good as new after some tough cleaning. All leakages will be taken care of when we put everything back again.


The fuel injection will run in 'closed loop control' so there's no need for the airpump no more. A few kilos less to carry around. In the box you can see the stuff related to the air pump that is not going back.


The electronic injectors have different dimensions than the k-jetronic injectors so the holes in the runners must be machined to suit. Now we have reached the point of no return, to be able to go back to k-jetronic we need to buy new runners. We had to make a device to hold the runners in the right angle when they are being machined.


One function which is not used in k-jetronic is Throttle Position Sensor (TPS). This created some problems because we didn't want to change the actual throttle body, but in some way Klotzakk managed to attach a TPS to the Porsche throttle body. Another sensor was installed as well. That was a Manifold Air Pressure (MAP) sensor. I haven't got any pictures of that installation. Both sensors are taken from a junk yard. I think they came from an Opel.


Because k-jetronic requires higher fuel pressure than the electronic fuel injection we didn't have to worry about that. The only thing changed is the plumbing and the added fuel pressre regulator. Now the fuel pressure will stay constant at 3 bar overpressure compared to the pressure in the manifold.


If you want to see more pictures and even some short videos visit Lars' homepage. There are more specific details regarding the software used and the user interface. Unfortunately it's in swedish only.

This Easter holiday I was out driving it and made a few small adustments. I have to say that I like the user intreface, it's really good. I converted my Corvette some years ago using an Electromotive TECII unit and it's software. The TECII software I had was based on DOS and it was more difficult to use. In MS you can load the settings from the unit in the car into your PC which was not possible with the TECII. Maybe the newer TEC software is better. Yoy should not be fooled to think that the tweaking job is done in 15 minutes, it's not. It takes a lot of driving and tweaking before it's near perfect. And then you enable the 'closed loop control' and the lamda sensor does the rest.

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