04-06-2015, 09:08 PM #1
having some vtech tuning issues any advise would help
first of all the ski is a 2012 rxtx260 mods are torx stage 2 cam,springs/retainers 4 inch air,fpr,ic relocation,thru hull with stock waterbox,ribbon delete,thermostat,15/20r prop lightened flywheel vtech tuned with vt 1100s.today i did some tuning air temp was 66 degrees water 48 i gave the 8900 jesus 401 a try with the vt1100 injectors idle was 13.5 wot 11.7 and dipped to 11.3 ish at points and thats with the fuel pressure set at 50psi a buddy of mine with the same setup runs 60psi in 80 degrees and air fuel is 12.4 aprox if im at 50psi now in this cool weather summer heat will put me much lower something seems off what do u guys think?
04-06-2015, 09:13 PM #2
So the ski is stock besides the Cam and 4inch air?
I don't see anything special.
Does your Buddy have the Cam? As that changed my set up on my PX
Also recalibrate your O2 sensor just to make certain of that.
04-07-2015, 05:26 AM #3
You are talking about WOT...but how much RPM? This is the question ...
More RPM = More Boost...remember Ignition and also fuel is related with Boost.
As i see you are runing stock supercharge.
04-07-2015, 06:23 AM #4
I have found it almost impossible to tune any motor without data logging.
You can only get into the ball park with a gauge.
Re fuel pressure, 50 is not enough on a boosted motor. AFR tuning is always best done with the ECU fuel tables based on what we see in the logs.
04-07-2015, 06:58 AM #5
a boost leak can make you run rich
so will having the cam retarded
using a rrfpr on most vtec tunes will be rich
your sure your gauge is reading correcley
trying to tune with a gage is not easy
50psi is fine if he is using his rrfpr
04-07-2015, 07:36 AM #6
RPms where 8700 ski ran strong but I was expecting to be over 60psi of fuel pressure with this setup/air temp I have another Afr guage I will be trying over the weekend just to b sure but I did a hard calibration should be on point. I guess it could be possible to have a boost leak somewhere but I don't think so with how strong it's running. I also tried the stock injectors my idle was 12.1-12.5 and in order to get the Afr where it needed to be I had to try 72+ psi of fuel and the ski fell on its face at wot and went lean my guess is the injectors where maxd or fuel pump couldn't keep up? Up to 70 psi it ran good and clean but Afr was 12.8+ stock injectors would probably work in the summer months.
04-07-2015, 08:23 AM #7
You cannot run the ski at 50psi static WOT. I bet your tune is compensating for the fact that your injectors are not atomizing for shit. That's the biggest problem with people tuning themselves. They compensate for weak/bad sensors or an improper setup.
Put your tune at 60psi so the injectors can properly do their job then get your tune right. An oil change is a lot better than a blown motor
04-07-2015, 09:24 AM #8
04-07-2015, 09:25 AM #9
SO???? Is this a problem with the SKI or a problem with the tune?????????????????????????????????
04-07-2015, 09:38 AM #10
It's a tune issue. Set it static at 60 and scale your tune. 14-14.3 at idle is what you want
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