K Multiplier Question
I'm working on my first 350Z build and am starting the tuning now using UpRev. I put in the ID1000 injectors and UpRev MAF GT (to go along with the twin turbos). I asked UpRev for some common tuning values as a starting point since I bought everything from them but they won't respond to my emails. Anyway, I have the minimum pulse width and latencies set for the injectors and ROMEdit set up the MAF table for the MAF GT. Fuel pressure is good and steady at a bit over 50psi. I have WB O2 sensors in each bank for measuring. I calculated a new K multiplier based on the larger injectors (1000cc vs 380cc) and the wider range of the MAF (about 180% over OEM) and came up with a K multiplier of around 15000. The problem is that as soon as it gets out of crank mode, it starts leaning out a lot. Using real-time tuning, I ended up with a K multiplier of about 31000 to stay close to target AFR across a small RPM range (idle to 3k) under no load. This seems abnormally high like something is wrong. Any thoughts or advice would be appreciated. Thanks.
since the upgraded MAF dont really change the voltage slope from what i have seen. usually it will be a bit lean and i would as a start multiply the maf curve 100% double it
Hey, I am tuning my 04 g35 coupe 6 mt on uprev as well.
I am having trouble getting the afr to be stable when the car is idling. i have 775 cc "fuel injector clinic" injectors, powerlab gt3582r kit. I am using a wideband innovate afr as well, (no fuel return system).
I used minimum pulse width value as 1.3 (anything above 1.6 and I cant start, anything below 0.9 and the car starts to do weird things, also extremely unstable afr values).
I have the latency values from the manufacturer as well however these are generic values for the same 775 cc injectors since I didn't give them my product id code (they were already in the car). I tried to use them, however the afr at idle still bounces between 14-16.5 (tried to load up the battery using seat warmers, high beams, radio, etc to get it down to 8v and increase/decrease slope that way but no real improvements).
Do you think any possible vacuum leaks can be a source of this bouncing (lets say from the couplers holding the charge pipes together?)
Any recommendations on what to do/look out for to stabilize the afr during idle?
Thanks
Rafal
I am having trouble getting the afr to be stable when the car is idling. i have 775 cc "fuel injector clinic" injectors, powerlab gt3582r kit. I am using a wideband innovate afr as well, (no fuel return system).
I used minimum pulse width value as 1.3 (anything above 1.6 and I cant start, anything below 0.9 and the car starts to do weird things, also extremely unstable afr values).
I have the latency values from the manufacturer as well however these are generic values for the same 775 cc injectors since I didn't give them my product id code (they were already in the car). I tried to use them, however the afr at idle still bounces between 14-16.5 (tried to load up the battery using seat warmers, high beams, radio, etc to get it down to 8v and increase/decrease slope that way but no real improvements).
Do you think any possible vacuum leaks can be a source of this bouncing (lets say from the couplers holding the charge pipes together?)
Any recommendations on what to do/look out for to stabilize the afr during idle?
Thanks
Rafal
Update: I didn't make any changes to the mpw or the latency values, i did some removed some % from fuel compensation table and changed maf values (corresponding to voltage) seems like it made a huge change. afr is somewhat stable now at 14.7-15.1 at idle
from data log afr corrections in both banks were about 96%-102% , much better than the previous 125% lol
from data log afr corrections in both banks were about 96%-102% , much better than the previous 125% lol
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stunt101
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Sep 26, 2013 09:21 AM






