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maxspeed
04-17-2007, 12:36 PM
does anybody use one of these? if so which model, and how well does it work?

onemoremile
04-17-2007, 12:43 PM
link?

maxspeed
04-17-2007, 12:47 PM
http://vastperformance.com/images/VAST_adj_TCD_web.JPG

looks hella cheap, but all the s4 guys use it with success

mike-2ptzero
04-17-2007, 01:26 PM
Oh no not another " defeat the map sensor mod".

maxspeed
04-17-2007, 01:32 PM
haha

dsswain
04-17-2007, 01:39 PM
does anybody use one of these? if so which model, and how well does it work?

http://forums.audiworld.com/s4/msgs/2628891.phtml
Here is a log of what it will look like, from a B5 S4. I have one on my B5 S4 with stock fueling, adjust FPR and MBC only. The TCD allows me to hold a bit more boost up top than the chip only would. I am holding 1.1bar to redline vs. .9 that the chip requests. I wouldn't do the TCD/MBC for the longest time, but I was surprised at how driveable it is, even with on/off throttle boost control. If I wasn't told, I wouldn't know that my car was operating on MBC only at this moment. (I think at higher boost levels it may become more apparent, but am not sure) There is a TON of information on audiworld in the B5 S4 form archives. If you are skilled with lemmie and comfortable with tweaking it may work for the B5 1.8t. Mine is fixed at 1.0bar. You may have better luck with the adjustable one, I don't know what the Requested boost curve of your software looks like.

mike-2ptzero
04-17-2007, 01:50 PM
http://forums.audiworld.com/s4/msgs/2628891.phtml
Here is a log of what it will look like, from a B5 S4. I have one on my B5 S4 with stock fueling, adjust FPR and MBC only. The TCD allows me to hold a bit more boost up top than the chip only would. I am holding 1.1bar to redline vs. .9 that the chip requests. I wouldn't do the TCD/MBC for the longest time, but I was surprised at how driveable it is, even with on/off throttle boost control. If I wasn't told, I wouldn't know that my car was operating on MBC only at this moment. (I think at higher boost levels it may become more apparent, but am not sure) There is a TON of information on audiworld in the B5 S4 form archives. If you are skilled with lemmie and comfortable with tweaking it may work for the B5 1.8t. Mine is fixed at 1.0bar. You may have better luck with the adjustable one, I don't know what the Requested boost curve of your software looks like.

But it also removes the over boost safety function of the map sensor the same as doing just a diode/mbc combo. This is why it is good to use a EBC with a over boost function instead of a MBC when doing this type of mod.

dsswain
04-17-2007, 02:18 PM
But it also removes the over boost safety function of the map sensor the same as doing just a diode/mbc combo. This is why it is good to use a EBC with a over boost function instead of a MBC when doing this type of mod.

Agreed, MBC is ideal and may be the only way to make it work depending on program and your goals. For the B5 S4. The Natural Taper of boost that is held resembles the requested boost cure of the x-chip (which most of us use). Example the chip may request 16psi tapering down to 13 at redline (new file). Adding an MBC we can hit ~17.5 and hold 16, so there is a taper. It's not exact but it's there, and for the most part just adding this we will run richer in the mid-range and leaner up top because the deviation between requested and actual is smaller there. (I'm sure you may know this but a bunch may not.) In theory I think with an EBC we would be able to up our midrange boost and keep the deviation between req and actual similar across the RPM my AF would look better across the board.

After seening what people have done on the B5 S4's with so little I think you can get a pretty good tune out of GIAC software, TCD, MBC/EBC and either adjust FPR/Injectors and MAF size.

I just wish whomever good luck because it can take many tries to get the right combinations and sometimes it just doesn't work. But for the ones that get it to go they get a complete fueling for cheap, and a dman fast car.

Again, there is a ton of information in the B5 S4 Archives, and I am not an expert, so if someone is going to try this. Sit down, grab a drink and do alot of searching/research and come up with a gameplan.

Or cut the BS and call Mike@VAST because he has done a ton of setups this way. B5 A4 and S4 alike

maxspeed
04-17-2007, 02:23 PM
thansk for the input [up]

UN-PIMP-Z-A4
04-17-2007, 02:43 PM
Oh no not another " defeat the map sensor mod".

LMAO...