Porsche 911 Twin Plug Conversion

Watch as John Edwards @ Costa Mesa R&D Automotive Machine Shop as he describes the steps that he uses convert a set of Porsche 911 cylinder heads from a single ignition to dual ignition (2 spark plugs). This modification is worth at least 30 horsepower on the dyno, all by itself. Yes, you do have to use a different distributor, or a CPU ignition module that has a waste spark. Don't forget to 'Click' and SUBSCRIBE! This is the NEW fiatnutz channel. And, oh yes, the heads were disassembled and cleaned...

[@chetjuall2269]

I remember doing the same machining and adapting the Bosch distributor cap to the stock distributor. Here are some comments:
1) The Bosch 12-wire distributor cap is incomprehensibly expensive but if the customer has money...
2) The distributor cap does not incorporate a centrifugal rev limiter. Two electronic rev limiters must be added.
3) The (large) 12-wire distributor cap was adapted to the smaller stock distributor. I machined a custom adapter for this out of Nylon.
3) Holes for access of spark plugs must be machined into the lower valve covers.
4) This modification achieves spark redundancy - a requirement for aircraft applications:)
5) This modification affords an improvement in idle smoothness.

[@MrShobar]

Nice work, as always. Many thanks.

[@ThatGuy-xd5fs]

Very cool

[@thinkerdoit]

For us non machinists interested in machining and Porsches, how is the set up determined? ie how do you insure it comes out in the correct place of the combustion chamber with the correct angle?

[@jaredrand2680]

thanks