Hi,



I have a stock Series 4 13B Turbo. I have just made the addition of a drop in K&N Filter and This Friday I have my car booked in for a new exhaust. 3" off the turbo into a 3" high flow cat split into a 2 1/2 " Duel system out the back with two high flow mufflers. Will I need an FCD or with the standard ECU be able to cope with these mods. I dont plan on doing any other mods to the car after this so will this be ok. any help would be appreciated.



Thanks,



Matt

yes, u do need a fcd. once u put it the new exhaust, it pretty simple to make one too. fc3s.org if u do not ur rear rotor will cut out too early i think

yah i think your gonna need one, especially if its cold out



mike

You will need one. While you are at it, get a Walbro fuel pump. This way you will not have to worry about your fuel system unless you get a bigger turbo.

I rang around a few Rotor performance places today and 50% said yes I will need one and the other 50% said it would be ok. If I don't put one on will my engine blow up or just run lean?

might blow. depends how u drive it actually. i drove mine around with my new exhaust without one for about a month. i just didnt go above 4k on any gear (that was ******* hard to do) better safe than sorry

With free flow exhaust and a new air intake on a s4 you will need a fcd or you wont be going very far. On a s4 the fuel cut is 7.5, and if you havent experienced fuel cut, well let me tell you its no fun. With those mods you could probably run about 8-10psi which is well in the limits of the stock intercooler. Get an FCD or you will be bogging like hell all over the place. And when you hit fuel cut, its very bad for your engine and you will be hitting it alot. I think i said 'and' too many times in that reply.. :(

not that much

Best to be cautious. No sense blowing a good engine. Get the FCD and the upgraded fuel pump so the ECU can accommodate the extra boost. And I hope I don't even need to say it, but be sure to run the highest octane gas you can find.

I have an FCD I'm not using...$30 plus shipping.



EDIT: It might be sold already.

Is the FCD easy to install? what does it involve?

Yes it is. It took about five minutes to install my Knight Sports deal. That included making it nice and snug with zip-ties.

NO!

yeah, run without a map sensor, it's a reat idea. :eek:

WTF unplug the map sensor ????

DON'T UNPLUG THAT LINE!!! LOL



if you don't get an FCD. chances are you will hit fuel cut. which means the engine will "stop dead" when you floor it, and you'll have to remove your foot from the gas pedal, then push down again to start going again.



if you do get an FCD. you will probably blow the motor from running too much boost LOL... well with the cat and only a drop in you might be ok...



first thing to get is a real boost gauge. 2nd thing is a bigger fuel pump.



then add your exhuast. if it hits fuel cut, buy an FCD, if it doesn't, then there is no need to get one.

You have got to be kidding.

I have installed a boost gauge and it's running around 8 - 10 PSI. I thought it hit fuel cut the other day but it was just the Intercooler pipe blowing off the turbo!! I **** myself. I don't think it is hitting fuel cut it revs through the range without any hesitation. Should I get a bigger fuel pump just to be safe?. Does having a bigger fuel pumpo mean that more fuel will be injected during the time due to the extra pressure?. Will that prevent it from leaning out?

A stronger pump should not affect the fuel being injected. That's what the fuel pressure regulator handles. With more fuel able to supply the injectors, they shouldn't ever go thirsty.



If you have to think twice if you should or shouldn't, then do it. It's just good insurance.

a bigger pump will add more fuel because the stock FPR is too small and can't bypass enough of the extra. it will also mean it won't run out of fuel and let the pressures drop. the fuel pump is the weakest link in the stock system. good for a max of 250hp. you are probably hitting that at 10psi.



once the pump maxes out, less fuel will get injected.





so you are not hitting fuel cut at 10psi on an S4 ??? weird.. maybe you already have an FCD LOL

At 10 psi there should be a fuel cut on a series 4 T2.Oh well some cars are special right off the assembly line.BTW Gardonitro:Don't come bitching to us when your engine blows.They do build FCD's for a reason. https://www.nopistons.com/forums/pub...DIR

people should know what they are talking about before they post.... if he's not hitting fuel cut. then a FCD is no use, infact he is better to not have one. not having, or having an FCD will not blow an egine. all it does is tell the ecu it is running less boost. it does not effect the fuel at all. the reason people blow engines is from lack of fuel. which the FCD does not effect. all it does is allow you to run higher boost. which inturn you must add more fuel. failure to add more fuel while running more boost will cause it to blow up.

Don't screw around with it, just get the FCD.

I have been looking into a few alternatives. Does anyone have any experience with a UniChip. Do you think this would be a better option over an FCD?. Apparentley you can control everything with it.

The cut is BEFORE 10 psi, its at more like 7-8psi. You will need an FCD, but it only fools the MAP sensor (which should NEVER be unplugged, jesus christ) into thinking its still under fuel cut, so you probably are going to run lean.



OR, you could invest an extra 250 into getting an upgraded factory ECU that would eliminate fuel cut, and tune the fuel and timing curves for your modifications. You would still need to upgrade the fuel system as with your mods, you will probably hit as high as 15psi.



Never heard of a unichip, one of the chips ive seen is from www.elprototypes.com

How much is that, so you wanna run sometime of piggyback fuel computer? Why not just get an S-afc?

In Australia they are $1450 installed and dyno tuned. What is an S-afc? How much are they? WIll I still need an FCD with that?

So, I went out last night after tightening up the clamps on my Intercooler. One popped off last week and I think they were both a bit loose so I may have been loosing 1 or 2 PSI through there. I drove around to get some fuel and stuff then on the way back home I thought I would open her up to see if she was ok. At about 6K in 2nd gear she hit fuel cut!!! So I backed off and drove home really carefully. FCD will be aquired and installed Saturday morning.

I have the FCD on now and she is all a ok. I'm pretty happy with it. No more fuel cut :-)

NOt sure what mod to go for next. Maybe a boost controller...