Power FC Swapping 1200 for 1680 secondaries; any simple PFC updates to keep the car drivable?
#1
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Rotary Freak
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From: South Jersey
Swapping 1200 for 1680 secondaries; any simple PFC updates to keep the car drivable?
I will be swapping out my secondary injectors and upgrading to 1680's with a full kit (kg parts/rx7store kit). I would like to keep the car drivable to at least make the two hour trip to get tuned. I don't have a datalogit; is there anything simple I can do from the commander to maintain drivability? Will the car drive ok without any PFC updates?
Thanks.
Thanks.
Last edited by moehler; 04-08-12 at 01:25 PM. Reason: Bad sentence
#2
You only have to calculate duty cycles for the primary injectors.
So all you have to do is adjust the injector size under "Setting ---> Injector", and account for any difference in injector lag.
The stock secondaries have a lag time of .77ms, so if your new injectors have a lag time of .85, you would change them both (Fr-Sc, and Rr-Sc) to +0.08ms
Your new injectors should come with a spec sheet.
Feel free to read page 26 here:
http://www.clubrx.org/media/pfc/PowerFC_FD3S.pdf
So all you have to do is adjust the injector size under "Setting ---> Injector", and account for any difference in injector lag.
The stock secondaries have a lag time of .77ms, so if your new injectors have a lag time of .85, you would change them both (Fr-Sc, and Rr-Sc) to +0.08ms
Your new injectors should come with a spec sheet.
Feel free to read page 26 here:
http://www.clubrx.org/media/pfc/PowerFC_FD3S.pdf
#4
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Rotary Freak
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Joined: Mar 2003
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From: South Jersey
^Thanks guys. Yeah, I was hoping if the car didn't drive very well I could tweak a few commander settings to make it more drivable. Hopefully it wont be bad at all... but I've never jumped to 1680's without a re-tune before so I'm not 100% sure.
#5
Your going to be able to drive it the same. Secondaries only come on under boost and at higher rpm, the injector difference isn't even that big either. I wouldn't even bother changing anything in the tune except change your lag to +0.16 (that's what I use). Until you. At least.
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