2 x cps = +6* timing

[scalper]

i am wanting to do this mod but curious if you guys that have done this are running automatics and will this mod work with automatic.reason i ask is rock city use to sell a similar cps and there add say will not work with automatic trannys.seems like it would still work to me.

[SilverXJ]

Mine is an auto, works fine.

[yuppiexj]

I will hazard a guess on this.

Anecdotal evidence, discovered by more motivated people than I, says that the AT and manual ECUs have different timing maps.
Something about the AT having more factory timing to give the AT similar driving characteristics to the MT.

I know my bone stock 94 XJ w/AT pings like crazy under light load immediately before downshifting.

[scalper]

thanks

[Desertjr]

Since closed loop is based on the 14.7:1 provided by the o2 sensor feedback, having the capability to bias the voltage(with the AEM) at any rpm and load less than the OL threshhold means that you have the ability to tune the CL map as well, instead of just zeroing the fuel trims(Split Sec, Apexi, etc). It's not a bandaid, but an awesome feature, and just a step below a full standalone unit. If you have an obd1(or 2 if you don't care about CELs), disco the temp sensor in the t-stat or use a certain value resistor inline that tricks the pcm to think that the coolant temp is lower than what it is and then you can be in OL 100% of the time and tune whatever map you want(with the SS and Apexi).

Now this I'm curious about, tricking the ecu into thinking your in OL(open loop) all the time. I'm using a apexi safc II to tune with so tricking it would be beneficial how? By being able to tune to what I wanted correct? Would this not have adversed effects like decrease in drive ability?
Wile cruising your in closed loop which should be 14.7:1 stoich? Running in OL all the time would give you 1 set or whatever AFR you tuned for correct? So you would have worse cold starts and cold running issues(rich)? And get worse mileage while cruising because your air fuel ratio would need to be acceptable for wot stuff..probably high 12s - low 13s AFR? Or could you still tune cruise for 14s and wot for whatever AFR was needed ect?

Again apexi safc II. 88 renix. Aem wideband, oem knock sensor.