84 Carrera with SSI headers w/ or wo O2 sensor

[yelcab1]

Have any of you run a 3.2L Carrera engine with DME electronics while using SSI headers on the engine? The stock headers combine the exhaust from both banks into one single Cat Converter whereas the SSI cannot do this.

1. Do you run the engine without O2 sensor?
2. Do you run the engine with an O2 sensor connected to bank 1 header and ignore bank 2?

[76FJ55]

I'm still on the stock exhaust on the 911, but I can confirm it is quite common on the 928 to run the O2 in a single bank and assuming the other should be equivalent. A lot of guys will run the narrow band (factory connected to the ECU) on one side and wide band sensor in the other connected to a rich lean display.

[Lyle O]

When I had SSIs on my '87, I ran with the O2 sensor for the DME in the one bank only and it ran great that way. Later I added a Wideband to run in the other bank also. All good. I am sure some theoretical level of perfection might be missing, but for this system it's just fine, IMHO.

[yelcab1]

All is well except that it has a bouncing idle for 15 seconds after a dead cold start up. What could be the cause? I think some of this is quite normal.

[Lyle O]

Check ICV or CHTS...

[Bill Verburg]

Originally Posted by yelcab1

Have any of you run a 3.2L Carrera engine with DME electronics while using SSI headers on the engine? The stock headers combine the exhaust from both banks into one single Cat Converter whereas the SSI cannot do this.

1. Do you run the engine without O2 sensor?
2. Do you run the engine with an O2 sensor connected to bank 1 header and ignore bank 2?

Just run the O sensor in the left bank, ignore the right

[BE911SC]

FWIW, John Walker disconnected my O2 sensor, adjusted the mixture with the tailpipe sniffer in place and the car has run great ever since. I think I had it in for a valve adjustment and oil change. Stock '84 3.2.

[yelcab1]

Originally Posted by Lyle O

Check ICV or CHTS...

I checked both, they are fine. I think idle mixture next, and then MAF