What coils to use on a NA twin plug?

[John at J&S]

A shop in Hong Kong is installing our latest unit on a NA twin plug car.

MoTeC ECU, everything is fine to 6500, then acts like the rev limiter kicks in.

Two days of emails later, he says he finally disconnected the J&S and his Bosch igniters misfire too.

His coils have 1 ohm primary resistance. I told him to change to something with 0.5 ohm, but I don't have a part number.

Number, please? Thanks much.

[NathanUK]

My stock 930 coil has a resistance of 0.7 ohms.
I'm sure Pelican could fix you up with one if they wanted to try it. http://www.pelicanparts.com/catalog/shopcart/911M/POR_911M_ELignt_pg9.htm#item38

Originally Posted by NathanUK

OK, here are the resistances

At the CDI connector with it unplugged

Coax to dizzy (green cable) is 570 inner to outer wire.
Brown to White (coil primary) is .7

Coil secondary (coil HT to either + or -) is 649

At the CDI box

31/1 to 31d is 0 (closed circuit)
31d to 15 is 672
31d to TD will charge briefly and then go to infinity (open circuit)
31/1 to TD also charges briefly and then goes to infinity (open circuit)

My CDI is a 930.602.702.00
Bosch number 0 227 300 004

[John at J&S]

Coils were not the problem. The tuner forgot that he programmed the MoTeC to rev limit at a certain "water" temperature.

[NathanUK]

Hehe