Hi, Folks, I need some help here.

I am planning to an install F-con S on my G35x AWD to see if it works
& let it run for a few weeks before installing S/C.
The F-con S is piggyback pre-programmed to HKS S/C (Rated 80HP only),
not turnable.

My installer think it'll run rich, may foul up the sparks, but will pose no danger
to my car.

So my questions is,

1, Should I install the two external injectors with Fcon before adding S/C?
I am thinking without the two injectors, it'll be runing less rich, right?
How could I tell if the Piggyback is working?

2, Would install Plenum Spacer (which make my car run lean, as I already have a Stillen Cat back ) with the F-con S make it less rich?

3, Would 1 step colder plugs reduce fouling? or make it worse?


Thanks

 

I would definitely not put the fcon on before you install the rest of the setup. Doesn't really make any sense to do so.

 

1. I would recommend installing everything at once! However if you have it in your mind to do as such, It is to my knowlege that nothing bad could happen to you motor minus running slightly rich!

2. Yes Plenum spacer should lean out the A/F slightly and should be fine for NA driving, i would be weary of plenum with SC kit installed!

3. I think running colder plugs would actually make the fouling worse! Since they are having an even harder time burning all that fuel and not enough air!

 

He thinks? I would say no. The EMS is not tunable and is tuned/mapped from factory for their S/C and the supplemental injectors. Running it without what it was designed for is not safe IMO. Even N/A engines can blow/get damaged if tuned incorrectly. Im on the paranoid side. Others may have different opinions. If you have to add/remove mods to get the A/F where it is supposed to be or safe then something is not right. Id just wait and put it all on at once so you can be sure of proper operation! HKS makes good products, but I wouldnt want to be the one fluke that gets his/her engine blow for some mysterious reason. My $0.02

 

the FCON S is definitely tuneable by an authorized HKS shop............that's what I gathered when I read the SCC reports on it.

but why throw it on? You have to have it tuned. Just doesn't make any sense to install it beforehand in this case.

 

Why? the f-Con S was designed to act as an EMS for a supercharged car. putting it on without the SC is not what it is designed for. basically (and i mean very simplistically) it pulls timing and drives the auxillary fuel injectors to safely run boost. with out the SC compressor, there is no point in pulling timing or running additional injectors.

 

Why??Just why??

 

If it's tuned for either MAF voltage or manifold pressure you should be fine (which I assume it is but I don't know for sure). Those high airflow/positive boost cells will be present on the maps but they won't be used because you either won't be flowing that much air (in a MAF voltage based tune) or won't be seeing any positive boost (in a MAP based tune). If it's a TPS based map then yeah, you could have some weird issues like way too much timing being pulled and too much fuel being provided, but then again, if your engine management is running a TPS based map as it's sole means of providing the correct timing and fuel, you've got bigger problems (namely, your tuner/parts suck ***).

 

just so everyone is clear on this: the F-Con S will only run the 2 auxillary injectors. it does not control the other six. i know because i have the HKS SC and to run 440cc injectors i had to get my ECU reflashed by technosquare to control them. i repeat: without running boost there is no need for auxillary injectors or pull timing

 

I don't think he was asking if there was the need for the additional injectors or the pulled timing, he was asking if he would run into any problems because of the way it is tuned, if he installed it on an NA car before he put his SC in. So that leaves the question that I posed above: "how is the F-Con S tuned?" Does it bring those injectors online on a MAF or MAP based fuel map, or does it use some other method. Same with the timing - is it MAF voltage or MAP based or is it TPS based or some other method which I'm not thinking of.

 

Just an update.

I have the HKS F-con SZ winstalled with the S/C together, thanks to the advices at 350z.com.


Now, My AFR is 14.5 Idle & 13 or 14 WOT.
It seems very lean at WOT.

My questions are.

1, My dealer wired the AEM 6-1in-1 gauge into Factory O2 sensor, which
is a winde band. Is this reading not accurate? I had this set-up in NA & I was getting 14.5 Idle & 12.9 WOT. Right after Install, I saw WOT 12.6 & now after two weeks, AFR is creeping up

2, Because I am able to get 13 or 14 AFR at WOT, does this mean the two External Injectors are working but not giving enough fuel or not working at all? How could I test to see if the two external injectors are even spaying?

3, Can I simply change stock injectors to 440cc & get better AFR without
ECU reflash? The F-con does not control the Stock injectors, only the two external injectors.

Thanks for your help.