Thanks for the words of support guys. The brown wires, in addition to retarding the ignition timing a little, also leans out the part throttle fuel mixture a bit. This can be verified by using a wideband mixture meter such as the LM-1. These wires were only connected for the California and Japan cars for emissions. These wires were the reasons California cars were rated 7 hp lower than the 49 state cars, with factory rated 0-60 numbers increasing from 6.1 to 6.7 seconds, IIRC. With more retarded ignition timing, NOx is reduced, and the leaner mixtures reduce HCs and CO. With most performance chips, it is best to disconnect the wires because the leaner mixture can induce light part throttle pinging. With the stock chip, it won't matter because the timing maps are conservative.

Judging from your picture Craig, you are running old 2k software. Just the upgrade to 4k software would make a great improvement to low and mid end torque and throttle response, in addition to the idle quality.

Sounds like I'll have an Authority chip for sale - cheap...and doing the 4k DME upgrade.

Luckily, the PO did have a professional solder in the chip socket when the Autothority chip was put in - I checked that closely while I was in there. I knew from Steve's FAQ that I had the original DME part number, with the soldered-in chip.

My idle does hunt a bit, too, so that'll be gravy!

Craig

Check here ( www.systemsc.com/tests.htm ) to see what performance chips
really do, i.e. "push" the timing maps. Some claim a difference, but they're
all basically the same!

No real secrets or mystery here, other than performance chip suppliers
violate the Porsche/Bosch copyrights to the chip microcode.

"Loren, is it a good idea to disconnect the brown wire on an 87-89 California market Carrera that is otherwise all stock (i.e. stock chip, engine/intake/exhaust?"

Yes, no problem as long as 91 octane is used. A DIY performance mod.
Most performance chip suppliers indicate this mod, which is the real
performance enhancement one notices when the chip is installed.