TurboXS says no fuel cut defender exists for our cars?

[strippedlug]

Okay I've been shopping around for a fuel cut defender for my 95 TSI w/ 1G swap. I found a TurboXS unit that says completely universal, and I was just about to buy it when I thought I should make sure and call tech support. The guy on the phone says he's pretty sure it will but that he would ask his boss. Comes back on the phone and says "actually no my boss says there isn't a fuel cut defender in the world that will work on DSM" That's a direct quote.

I know DSMlink has the feature, but I don' thave the cash to fork out, and I can tune just fine with what I have.
The problem is that I'm about to install a big 16g on tomorrow and I know fuel cut will be an issue (it already is on cooler mornings).

Either this guy's boss was just straight wrong, or there just has to be a way to mod this issue. I've searched vfaq several times as well as google and others, and any links describing a do-it-yourself fuel cut mod are dead links. You guys are my last choice and since it's a common problem (fuel cut in general), I know you guys have my fix in those brains!
Oh and I also know that proper tuning of my AFC can and will DELAY potential fuel cut, and I have for the most part I feel, but I want flexibility. Basically I just don't want the fuel cut demon to attack me on race day! Thanks guys

 

[strippedlug]

A little more searching I found this which confuses me and excites me at the same time: Quoted from another forum:
"There is no such thing as a mas installed fuel cut eliminator. There is however, a fuel cut "delay". Basically you wire in a potimeter into the barometric pressure signal on the mas. The signal is lower, hence the ECU thinks the car's intake is less dense air. Less Dense air = less oxygen= raise the amount of air that the mass can count before you hit fuel cut. "

To those of you with 6 bolt swaps this may sound familiar. I have a 10K ohm pot on my barometric pressure sensor to keep the famous phantom misfire from occuring. Basically my ECU never looks for misfires so there never is any injector shut down or limp mode. So is this the exact same mod serving two different purposes?

 

[i'm boosted]

You can go eprom ecu and have them remove it or see if you can find one of the ole school HKS FCD. They will work in a 1G DSM, I am not sure if it will work in a 2G. Do a search HKS FCD. There are alot of different opinions on this device, and you should take them into account

-Brian

 

[wt71gas]

Your profile doesn't say if you have bigger than stock injectors but you have everything else you need pretty much beside those. You can reliably go as big as like PTE 680cc injectors on an afc. You won't have fuel cut then so no need for any kind of fuel cut defender. Use you afc for what its made for

 

[strippedlug]

Your profile doesn't say if you have bigger than stock injectors but you have everything else you need pretty much beside those. You can reliably go as big as like PTE 680cc injectors on an afc. You won't have fuel cut then so no need for any kind of fuel cut defender. Use you afc for what its made for

Thanks for the replies. Actually I probably need to update the profile, I haven't checked. No they are stock injectors. From setups I've seen similar to mine, I should be okay at least for a while on stock injectors with a big 16g. Sure they will be running at almost max, but it's not forever. In fact injectors are another thing i'm currently shopping for.

Just so I know I understand you, bigger injectors will help delay any fuel cut? I was under the impression that it's the air entering the engine that makes the ECU "panic". Please don't haze me, I really want to UNDERSTAND the system, not just take it the nearest tuner and drop the car off. Here's what I'm working with in case my profile isn't current:

95 TSI
92 6bolt bored .020 over
Wiseco Pistons
Eagle rods
2.4 new crank
Clevite bearings
14b turbo
Apex-i Neo AFC
Walbro 255 FP
MBC
aftermarket boost gauge and wideband o2

WHAT I"M GETTING TOMORROW
big 16g
t3 flange adapter
2.5in o2 housing

You know my concerns about fuel cut, so in your opinion what is my wisest move to prepare for the installation of this new turbo?
Aeromotive AFPR?
FCD?
Injectors?
Or do I just need to sit down with my AFC and tune better?
I'm not about half assing any project, but I do, like any normal blue collar, have to piece things together.

 

[snox135]

You need to get bigger injectors and the afpr. Also why are you getting a T3 adapter for a 16g?

 

[i'm boosted]

Get larger injectors and tune with the AFC that is the best thing to do. The danger with the FCU is that you are fooling the ECU into thinking there is less airflow in turn making the car run leaner than what is considered safe.

-Brian

 

[1_2befast]

The afc intercepts the signal from the MAS and scales the values and then sends the new signal to the ECU. Therefore the ecu thinks that the engine is getting less air than it actually is. This is why the injectors dont fire as long on a larger injector with a properly adjusted AFC. Basically setting negative values in an AFC will keep you from hitting fuel cut. Bigger injectors allow you to use these negative values and still get enough fuel. Or at least that is the way I understand the system. If I am wrong some one please correct me, but it makes perfect sense. Hope this helps.

 

[strippedlug]

You need to get bigger injectors and the afpr. Also why are you getting a T3 adapter for a 16g?

Was told it came with it. My friend has it at his house, he says it's got a t3 flange. I questioned it also, believe me. I'll know for sure tomorrow.
I'll shop for injectors then. More money than I was planning, but I'm definately glad I asked you guys.

 

[strippedlug]

The afc intercepts the signal from the MAS and scales the values and then sends the new signal to the ECU. Therefore the ecu thinks that the engine is getting less air than it actually is. This is why the injectors dont fire as long on a larger injector with a properly adjusted AFC. Basically setting negative values in an AFC will keep you from hitting fuel cut. Bigger injectors allow you to use these negative values and still get enough fuel. Or at least that is the way I understand the system. If I am wrong some one please correct me, but it makes perfect sense. Hope this helps.

Yes you're right it does make perfect sense. Bigger injectors don't NEED to stay open to deliver the same amount of fuel as OE injectors.

So 680's should be about right? Thanks everyone

 

[Talesin]

Biggest I'd go with an SAFC would be 650s. You really shouldn't need too much more with a B16G, and it'll help reduce idle/low-end drivability issues.

While the SAFC lies about airflow to compensate for pulse width, there's another problem with running larger injectors.. the bigger they are, the more the actuator inside tends to lag.. what's known as 'deadtime'. An SAFC cannot compensate for the increased injector deadtime, so when you start getting too large, the injector doesn't open like the ECU assumes it does. It lags, so less fuel gets through, and idle suffers. Doesn't hurt so much at the midrange and top end, due to the shorter times between actuation.
This is where DSMLink and the AEM EMS come in... they *can* compensate for global deadtime, so you can run injectors as large as you like, with no problems once the new deadtime is dialled in properly.

And HKS made an FCD unit for the 1Gs... it was a bad idea. Fuel cut is the ECU's final attempt to save the engine from a catastrophically lean condition. The only thing you gain by removing/preventing it is a blown engine.

 

[wt71gas]

Fuel cuts whole design when mitsu put it in is to shut down the fueling system when the injector duty cycle gets too high (maxed out). I could almost bet you are very close to if not at 100% duty cycle and safe is around 80%.

680cc is about as big as you want to go with an afc. That will work fine but if you wanna go to bigger injectors you really need something like dsm link.

 

[strippedlug]

Thanks for the info Talesin. DSMlink is like a dream for me right now. As soon as it's possible, it's mine. But in the meantime I'm doing what I can with what I have and I"m so happy I decided to ask the opinions of you guys.

I just bought an Aeromotive AFPR w/ gauge after my last post, so that's on the way. Now I'll just find some decent 650's and I should be set until DSMlink becomes reality. So many features I'd love to have with that, including NLTS!
Anyway last question I promise! What's a reliable company to go with for my soakers? Wt71gas mentioned PTE? Any other opinions on this matter? I'm going to research and window shop right now

 

[Talesin]

Personally I like FIC, they seem to be pretty reliable, and aren't too pricey, especially if you catch them during one of their seemingly clockwork-regular sales. Got my set of 850s for just a little over $200. Now I just have to find a local shop to socket my ECU... had DSMLink sitting on the shelf for almost a year now (woot for birthday cash!) but no local shop wants to do the work, and I really don't want two to three weeks with no car to speak of. :b

 

[thekellbeast]

You're running a 14b on a 2.4? How's the low end on that thing? Lol.

 

[strippedlug]

You're running a 14b on a 2.4? How's the low end on that thing? Lol.

It's fine. My other turbo just had too much shaft play and I didn't want to waste my new bottom end because of metal shavings. The 14b has served it's purpose, but now it's time to say goodbye