Positive or negative figures for STFT/LT of 7-13% and 9-10%?

 

If I remember right that is normal for the Fit. My fuel trims in the Civic are -3.1 winter to -10 in summer.

Congrats on the ultra gauge and here is the instructions to help you set it up and explain the numbers. http://ultra-gauge.com/ultragauge/su...ser_manual.pdf

I always thought that the fuel trims should be close to 0. Its better when the ecu pulls fuel, this way the engine always have enough fuel even though I seen it go positive during acceleration. Tech - Closed Loop

 

Mine are all positive. Rarely dips negative at all.

 

That indicates greater than stock VE, as in extra air mass that needs the ECU to add fuel to maintain stock AFRs in closed loop operation. If you are getting full stock advance timing, that would equate to more torque.

Is the CAI your only VE mod at the moment?

 

Timing is definitely advancing. I did a quick glance and saw 30 degrees advance at one point I believe. Its usually 10-15 degrees advanced.

Intake is the only really mod. Stock exhaust. I did do a throttle body coolant bypass, but I don't think that would make much difference at operating temp.

 

Krimson Cardnal did a nice write up and his fuel trims were 9.8 on average. https://www.fitfreak.net/forums/2nd-...uel-grade.html

I would not worry too much until they go higher. http://www.aa1car.com/library/fuel_trim_wellsmfg.pdf

 

Well I found some good/bad news.

The good news is I found the culprit for my strangly high fuel trims. the bad new is its a vacuum leak inside the fic unit. Testing with vacuum pump confirmed it.

I disconnected, and my fuel trims now stay around +3.81.

Interesting observation, pumping the brake pedal will make the ST jump much higher. Maybe due to the release of pressure from the brake booster? very interesting.


*Edit

That would probably explain my jumpy pressure readings as well.

 

Maybe you found another leak? My fuel trims stay the same when braking.

Glad they are down. Maybe KC has a problem too.

Looks like the UG fixed a few problem.

 

Try pumping the brake pedal at idle, or 2000rpm.

 

I will next time and let you know. I have a Civic right now but its a Honda. I will also put my UG on the new Accord and see what happens on that car. My lease is almost up so I have to decide if I keep it or trade it in. I am thinking about another Fit or CRZ. I need to get great mpg because I drive a lot.

 

That (+ 2-4%) sounds much more consistent with the sort of airflow bump I would correlate with a CAI. And yes, because of the pulsing draw valve events have on the system it would also go a ways towards explaining the erratic signal.

I knew something wasn't right all the way back on post # 75 when you put up that screen shot lol

 

I tried pumping the brakes, the first one no difference but every one after the short fuel trim raised 1.28. I guess that is not a good idea. I think it adds fuel because it thinks I am about to take off.

 

No.. it adds fuel because manifold pressure changed and instantaneous mass flow increased.

 

hey DSM, i PM'd you a couple times, but no response. I'm wanting to jump into forced induction with my GE8, just looking for a simple starting list of what i will need/what you suggest.

 

I have a couple with drafts type up that haven't gone out, but I don't see your name in there...

When did you PM me?



If you want me to design your setup, I take modest donations to my Fit fund.

If you need me to source parts for you, I take a finders fee.

If you want me to tune or consult its on a per PM/Text/Call/Email basis.

Just putting that out there so we don't have any surprises. This is the time of year where all the series are starting to wrap up, at least in the northern portion of the country.

WCF and MOD are coming up too and I have been swamped, so you'll have to bear with me.. paying clients get priority.

 

I don't remember when I PM'd you, it's been awhile.
Well I'm just trying to source/buy parts first.
My goal is 13 seconds in the 1/4 mile without work to the internals if possible while staying fairly street friendly, low boost, and reliable.
I'd like room to eventually go 300+whp while staying with the same setup and just upping the boost and then possible internals.
I inderstand you being swamped and other priorities.
Like I said though, I'm just looking for a starting parts list for the above I mentioned. Like which turbo, intercooler, and whatever else you recommend. I went to to vent to atmosphere. Also is there anything I should upgrade? Spark plugs? Radiator? Etc... I know RSX-S injectors are plug-n-play but how much HP are they good for? Thanks.

 

DSM, feel free to PM me about the above, thanks.

 

Okay, so I've got a few things out the way and I can properly address this for you now

That would, at the least, entail considerable design work, a 13 sec/300whp Fit is not a run of the mill build by any means. It would make you one of just a handful world-wide.

You are looking to more than triple stock output and cut 5 seconds off the quarter-mile time. This will be competing with Mustang GTs and Camaro SS's with good drivers, tires, fuel and good atmospheric conditions.

It is definitely do-able though.

The ET is not something I can promise you, I can however design you the best possible combo to get a trap speed that would put you in the 13's if you can combine it with a good driver..

A large component of the ET, is going to be entirely on you.

PM me with everything from that post, your zip code and a realistic budget.

This is going to require more than a few hours on my part, so please be prepared to compensate me for that. We can discuss rates before proceeding from there.

 

Well.. Currently I run low 16's in my fit and that was with bad launches and a little loss of traction. I just put on wider wheels and tires so that should help... But yeah I will PM you

 

finally got my vacuum leak fixed, and re-installed the fic. the map signal still bounces a little, but not nearly as bad as it did.

The good new is my fuel trims are the same as stock now. I had to adjust the IRT to 600 to get it perfect tho.