Air Cooled Porsche 930 Turbo Madness

In the back, a 3.3L single turbocharged flat six engine which, in stock form turns out 300hp and seems to run decent once it’s up to temperature. It’s got a very common Borg Warner K27 turbo upgrade along with an Andial Racing intercooler and a Tial external wastegate with a 1.2 bar spring controls boost.

The stock distributor has been ditched in favor of an Electromotive XDI ignition system that controls timing and spark while a cat-less Billy Boat performance exhaust enhances the sound of the flat 6.

A compression test revealed 115-120psi in the cylinders, which isn’t bad considering factory spec is 124psi. That means the engine should be in good working order but just to be sure I’ve decided to swap the pistons and cylinders for Mahle’s 930 Turbo Piston and Cylinder Kit. Not only does it increase displacement from 3.3L to 3.4L but Mahle builds many OEM parts for Porsche so I know that this is the kit to go with for reliability and better than stock performance.

Speaking of, the plan to upgrade the original CIS fuel injection system to a more modern day EFI setup. It’s not a cheap endeavor but the only way to go if you want a reliably and fast 930 Turbo. Currently turbo lag is atrocious. For a 3.3L engine, it spools worse than most 4-cylinders. The 930 Turbos are known for their slow spool up but as I mentioned with a proper engine management system and EFI that won’t be an issue.

I want to be able to fire up the 930, drive it with modern day reliability and performance. While some may think that it’s getting rid of the charm of the 930 Turbo, I ask what’s so good about antiquated technology? I’d rather have a turbo engine that spools quickly, has good partial throttle response, and cruises well.

I’ve gotten used to the noxious gas stench as the engine warms up. It pretty much runs pig rich all the time. Don’t even ask me about partial throttle because it doesn’t exist. These cars are great stock but once you begin to modify them tuning the CIS system that controls fueling is tedious and very archaic. A previously installed Electromotive XDI system is supposed to help the stock tune but in reality it’s not much better since it’s limited to 0-3000rpm and 3000rpm+ increments of control.

A dangling map sensor with some sketchy adapters to plumb the tubing to is among the many things that need to be replaced and fixed on this engine.

The worst part about this particular 930 is the 4-spd transmission. Not only is it hard to get into gear but 2nd and especially 3rd gear synchros are worn out resulting in crunchy gear shifts 75% of the time. A transmission rebuild is a must.

I’ve replaced the stock shifter with a Wevo Billet Shifter and it’s helped tremendously with the slop. I’ll save the install story and review for another day because it’s a long drawn out job.

Even with all these headaches, there’s something indescribable about the experience behind the wheel of one of these things. It’s pure, raw and analog.

As you can imagine there’s a lot that needs attention on this 930 but aside from being a great learning experience, I’m hoping to build a classic Porsche that runs and drives like its newer counterparts.