Fuel Cut sucks....

[EvilNCarnate]

I was driving to work today and experienced fuel cut, damn does that suck ass. I installed my APEXI AVC-R last weekend and have been so busy I havent taken the time to set it up fully.

This morning I am driving to work and this acura rice boy comes flying up to me and attempts a high speed pass. Well I of course saw him coming as I watch my mirrors like a hawk. I had the timing down perfect with my downshift so I was ready to floor it as soon as he got next to me. Well he got nose and nose and then I hit it. The down shift was from 3rd to 2nd and this was a main street in the city. I went from 40 to 65 in seconds, pulled away hard and fast and in that same 2 seconds it took to pull away I hit fuel cut. The car felt like I hit a wall, similar to what happens when you pop the y-pipe. Except the whole car said FU instead of just tagging out. I quickly shifted back up and looked at my boost controller to see it flickering screens like it had just reset.

Now I figure it was one of many things, either I hit fuel cut do to the learning mode being on, or my laptop bag hit the button I wired up for scramble boost. I havent figured out where to put the button so for now it sits in the passenger seat with the boost controller. I just cant figure out the best location for mounting without blocking a vent or the controls to the stereo or climate control.

[Monochrome]

How much boost are you trying to run?

Stock injectors right?

[EvilNCarnate]

I have it set at 1.0bar but I also have the scramble boost switch wired up and not actually installed anywhere and my laptop case slid and hit the button. My turbo timer is set up to log boost and acceleration/RPM's and adjust time down on those factors with a minimum setting of 1 minute.... anyway it holds peak values until the peak has been exceeded and the peak on it showed 1.16bar so right under 17psi. 1bar is 14psi and I havent had a problem until today. I am going to tune it in this week.

[EvilNCarnate]

4500rpms hit 18psi and damn did it feel strong. I need fuel mods but I also need to tune this down. Anyone have experience with the AVC-R?

[jackhammer]

Fuel cut can be frightening if yur not expecting it

[My92Stealth]

[quote=""jackhammer""]Fuel cut can be frightening if yur not expecting it [/quote]

First time it happened to me i nearly shit myself.

[EvilNCarnate]

I thought I had broke the car when it happened, then it hit me.... check my last boost level as its probably fuel cut. Then I did it again to check and sure as shit.

[Monochrome]

So wait, you're complaining that you can't run 18psi with stock turbos and fuel injectors? Please tell me you have a way to log knock.

What's your gain set to?

Watch the boost gauge and do a 3rd gear pull (on a clear stretch of highway). Does the boost climb to 1bar, then creep up to 18psi before dropping off around 5500rpms?

[EvilNCarnate]

[quote=""Monochrome""]So wait, you're complaining that you can't run 18psi with stock turbos and fuel injectors? Please tell me you have a way to log knock.

What's your gain set to?

Watch the boost gauge and do a 3rd gear pull (on a clear stretch of highway). Does the boost climb to 1bar, then creep up to 18psi before dropping off around 5500rpms?[/quote]

No my complaint is that I am hitting 18psi so quickly. I am trying to tune the boost controller to 14 psi and have been doing pulls to get the right balance because I dont want to be maxed out right out of the gate. I know I need larger injectors, fuel pump, hot wire and fuel controller and had planned on purchasing them before I had to get a minivan, damn kids.....

Yes I have a datalogger and have hit a few counts of knock, but that is why I am trying to get this thing tuned right.

3rd gear pull, well I hit 18psi and seemed to be climbing still at 5500rpms, slow but climbing. I am actually shocked that these turbos are spooling so high for stock with 109k on them. Granted they were babied the whole 109k but still.

I am planning on setting the controller to 6psi and turning learning off and see if I can map out the build to 6psi and then adjust it to 14psi. Since I have two options for settings I will leave the 6psi as my DD and 14 for ass kicking times. Plus I have the scramble boost option to let me spike out if i get in a race.

[Monochrome]

Do you have equal length wastegate vac lines? Better yet, how do you have the vac lines for boost controler setup?

I've never had great luck with "learning" boost controlers like the HKS and apexi because you'd always be fighting with overboost or boost spiking. What they're actually learning is something refered to as GAIN which simply is how fast the boost comes on and a lot of times, they're off.

If you have too high of a gain, then the boost controler solinoid doesn't respond fast enough to how fast the pressure comes on and thus, you get more boost than what you want, or it'll spike and fall back to your set boost.

Scramble boost is another can of worms that I personally see no use for. Ultimately, the boost controler is your left foot. Set the boost to your max and if you don't want to push that much air, then don't push the pedal that far down.

[EvilNCarnate]

[quote=""Monochrome""]Do you have equal length wastegate vac lines? Better yet, how do you have the vac lines for boost controler setup?

I've never had great luck with "learning" boost controlers like the HKS and apexi because you'd always be fighting with overboost or boost spiking. What they're actually learning is something refered to as GAIN which simply is how fast the boost comes on and a lot of times, they're off.

If you have too high of a gain, then the boost controler solinoid doesn't respond fast enough to how fast the pressure comes on and thus, you get more boost than what you want, or it'll spike and fall back to your set boost.

Scramble boost is another can of worms that I personally see no use for. Ultimately, the boost controler is your left foot. Set the boost to your max and if you don't want to push that much air, then don't push the pedal that far down. [/quote]

BLASPHEME

I am using the stock lines for the controller so I know for a fact they are not equal lenght. I am working on tuning everything in and slowly am getting it closer to where I want it. The problem I found was setting it to 1bar and 60% gain just doesnt work for me. I like having instant on boost and a good strong build up to around 6000rpms. I am working on calibrating the selections for both the boost level and the gain level so I can get it to do just that. Only problem so far is its spiking out.... my thought of course is that the spike is related to the vac lines, but I know I can compensate for that. I now have it hitting 5500rpms before it spikes to hell.

Side note: the vac lines will be evened up when I do a vac line reduction, I am just waiting on it because I plan on purchasing all platinum cured silicone lines in all the sizes for our engine bay and then using only brass or plated metal fittings. No plastic fittings here...

[OBXboost]

So under stock conditions, what really is limiting you to 165 at 5k in 6th gear? Is it fuel or timing? Or just HP?

[EvilNCarnate]

Distance... I dont think you will easily find a stretch of highway long enough to wind 6th gear out... now I have a 5 speed so its a guess. Of course the more HP you have the faster you will find the end of the gear.

[OBXboost]

[quote=""EvilNCarnate""]Distance... I dont think you will easily find a stretch of highway long enough to wind 6th gear out... now I have a 5 speed so its a guess. Of course the more HP you have the faster you will find the end of the gear.[/quote]

4 mile long bridge. It held at 165 for a mile before I let off. It just wouldn't go any faster.

[EvilNCarnate]

Must be the HP then. I only hit 140 when I test drove my car, the sheer oh shit factor of going that fast the first time out of the gate was good enough for me.

[OBXboost]

I dunno. Could be.

[Monochrome]

[quote=""OBXboost""]So under stock conditions, what really is limiting you to 165 at 5k in 6th gear? Is it fuel or timing? Or just HP?[/quote]

Just HP.

Too much drag, too tall of a gear.

[TheHarleyMod]

[quote=""Monochrome""]Ultimately, the boost controler is your left foot. [/quote]

I think you mean your other left foot