2001 A4 Gt2871R build Unitronics MAF-LESS tune

[f15046]

I haven't posted too much about installing a Garrett gt2871r on my 2001 A4 quattro. I am still running stock internals for now, until I build a spare AWM engine that I have.

Parts:
-Garrett gt2871r (t25 flange) exhaust housing adapter to V-Band
-PES manifold
-custom made water and oil lines (from Summit Racing)
-Unitronics BT tuning (MAF-LESS, eliminate SAI, )
-550CC Genesis injectors
-Greddy Profec B Spec II EBC
-3" exhaust system
-Electric fan (eliminated engine driven fan)
- Walbro 255lph fuel pump
- Custom 3" Downpipe
I am sure there are a few other parts I am forgetting to put on the list. I installed this at the end of June 2008, and have put about 6000 miles on this setup. It runs great! If anyone has any questions or suggestions, let me know.

By the way I bought most of this stuff used and spent a total of about $2900. The tuning and injectors alone were $1250

[Don Supreme]

Should spool nicely...

Why 550cc injectors?

[bassed]

Uni 630cc file, 630cc Injctors and Snow STG2 with a dual nozzle setup.

[mike-2ptzero]

Might want to relocate your intake filter, that thing is just going to suck up hot air coming out of your radiator. I relocated my outside temp sensor to that spot and saw temps of 50 degs higher then the actual outside air temp in front of the radiator.

[f15046]

034 motorsports recommended the 550cc injectors, and I've never heard anything bad about the 550's. Is there any difference b/t the Uni 550 file and the Uni 630 as far as power?

I will reconsider building an intake. Even where the filter is now, I am only seeing Intake temps that are 10degrees above the outside temp. So I would say that's not too shabby.

[bassed]

I don't recall UNI specifically tuning a 550cc file. Intake temps make the world of a difference.

[zrowcool]

are there any advantages for going with a bottom mount manifold instead of a top mount? i see more top mounts on members cars than i do bottom mount.

[bassed]

are there any advantages for going with a bottom mount manifold instead of a top mount? i see more top mounts on members cars than i do bottom mount.

Most are running the ATP, which is side mounting. PES used on this setup was 2nd hand, PES only sells kits unless Tony has decide to sell the Mani alone. The top mounting are all T3 flange GT30 or larger setup Tunnin either one f many Tubules available of the SPA cast Mani (I think there are 4-6 of us now).

[Don Supreme]

are there any advantages for going with a bottom mount manifold instead of a top mount? i see more top mounts on members cars than i do bottom mount.

BATS probably wouldn't fit on a bottom mount setup.

[mike-2ptzero]

BATS probably wouldn't fit on a bottom mount setup.

Correct. Just not enough room to fit the turbo next to the frame rail, plus the runners hitting the compressor housing becomes an issue since the turbo needs to be located further back because compressor housing is much larger and to allow room for the much larger inlet hose/pipe. Even the side mount log manifolds like the ATP and ATP copy place the turbo too far forward to put a 4" inlet hose/pipe or a big enough filter onto the inlet.

[.Mad Hatter.]

which route are you going with the intake/TIP?

[pipe7284]

nice!!!1

VIDEOS!!!!!

[mike-2ptzero]

which route are you going with the intake/TIP?

He is running a mafless tune which means he can just throw a filter onto the turbo inlet.

[.Mad Hatter.]

ah good point...i didnt even think about that.

ok, for arguements sake, if you were say running the UNI 630cc file with the 3" MAF housing and TIP with the same turbo, which would be the best source of air intake?

[f15046]

You would have to make your own intake for that setup. Right now I am just running a filter on the turbo.

I will get some vids eventually.

[eurojuce]

You would have to make your own intake for that setup. Right now I am just running a filter on the turbo.

I will get some vids eventually.

Hi
This is where I want to go eventually, right now I'm running a GT28R setup (GT2871R is next step). Question, with your MAF less file, how does it run? I heard that I should stick with the MAF for daily driving...what's your opinion.

[317ssayzarc]

WTF is that gasket that you're using for the turbine outlet?!?

Please tell me you will get a real gasket and that is not RTV red?

[Militant-Grunt]

WTF is that gasket that you're using for the turbine outlet?!?

Please tell me you will get a real gasket and that is not RTV red?

Ahaha, certainly looks like it.

[f15046]

I drive mine daily everyday, 4 days of the week are 100 miles round trip. It runs perfect and has never missed a beat.

Yep thats red RTV, and it hasn't leaked.... YET. But yeh next time I screw with the exhaust I will be putting a gasket in there.

Another update: I replaced the 1st O2 sensor (wideband sensor) just for the hell of it b/c the car has 120,000 miles on it. The car seems to be a tad more powerful and more responsive.

[Don Supreme]

Is it just me or is the compressor wheel on that turbo a little fucked up?

[317ssayzarc]

I drive mine daily everyday, 4 days of the week are 100 miles round trip. It runs perfect and has never missed a beat.

Yep thats red RTV, and it hasn't leaked.... YET. But yeh next time I screw with the exhaust I will be putting a gasket in there.

Well you are lucky that those two flanges are well machined, because that RTV has long since burned off


How's your mpg?

[f15046]

Yeh the turbo fins are fudged up, only on the very tip, the part you can see through the inlet of the compressor housing. I bought it that way.

I get around 25-26 MPG for half city driving and half highway. If it's straight highway miles it well get 30mpg.

[a418ts]

i really dont know abotu a MAFless tune, but what does it do ? like what difference does it make.

I'm getting a similar kit like this so i want to know what will be best for the best performance but without effing up my engine.

[mike-2ptzero]

i really dont know abotu a MAFless tune, but what does it do ? like what difference does it make.

I'm getting a similar kit like this so i want to know what will be best for the best performance but without effing up my engine.

Just means that the ECU isn't dependent on readings from the Maf sensor to adjust fuel or adv timing. This is all done by the ecu using speed density and using the 02 sensor as the main sensor for hitting the right AFR.


This means there is 1 less sensor that can go bad causing the car to run worse and less restriction in the intake system for the turbo which means better flow and more power.


Not 100% sure the TIP cars can be tuned mafless seeing that the TIP controller does depend on the MAF when it comes to choosing gears. I guess this is something one of the tuners would need to answer.

[adr3naline fix]

I have almost the exact same build! awesome stuff

[f15046]

MAFLESS-ftw! Its damn good setup, great daily driver, and super fun to drive. You should post up your build.

[Cecchini]

Just means that the ECU isn't dependent on readings from the Maf sensor to adjust fuel or adv timing. This is all done by the ecu using speed density and using the 02 sensor as the main sensor for hitting the right AFR.


This means there is 1 less sensor that can go bad causing the car to run worse and less restriction in the intake system for the turbo which means better flow and more power.


Not 100% sure the TIP cars can be tuned mafless seeing that the TIP controller does depend on the MAF when it comes to choosing gears. I guess this is something one of the tuners would need to answer.

Don't mean to get off topic sorry for the newb question but can pre-2000 engines run a mafless tune?

[bassed]

Don't mean to get off topic sorry for the newb question but can pre-2000 engines run a mafless tune?

NO, not unless you add a MAP and go SEM.

[f15046]

I don't think so. The reason the 2001's can is they have a wideband o2 sensor that the ecu uses to keep the Air/ fuel ratio in check. The 2000's ECU uses a narrow band o2 therefore must use the MAF to keep things in check.

[blkb6a4]

2001's also have a map sensor

[bassed]

I don't think so. The reason the 2001's can is they have a wideband o2 sensor that the ecu uses to keep the Air/ fuel ratio in check. The 2000's ECU uses a narrow band o2 therefore must use the MAF to keep things in check.

2001's also have a map sensor

He has a 99' gents, not a DBW (2000-2001).

[adr3naline fix]

MAFLESS-ftw! Its damn good setup, great daily driver, and super fun to drive. You should post up your build.

I should! When it isn't -9*F with a windchill of -31*F so I can get some close up pics! :(

[f15046]

go ahead and write a description and post up, you can add pics later.

[Pscheoverdrive]

ah good point...i didnt even think about that.

ok, for arguements sake, if you were say running the UNI 630cc file with the 3" MAF housing and TIP with the same turbo, which would be the best source of air intake?

I'm running a GT2871 Elim, but here's my setup:




You'll have to excuse the DV return hardline. :P I have an ATP 3" TIP kit, but I ended up cutting it down a lot. I was having trouble trying to snake the 1" DV return line around two 90%%d angles b/c it kept crimping, so I went to Lowes and bought some plumbing fittings. :P For some reason, ATP's elbow has the DV return line on the wrong side of the elbow, but I imagine the use the same elbow for several kits and they're just saving money on machining or something.

[Pscheoverdrive]

Oh, and my intake temps are typically less than 10%%d F less than ambient with an Evo Racewerks Comp FMIC.

[f15046]

Well a little update.
The car has been running great. The setup ran a 13.4 in the 1/4, with a 2.0 60ft time.

Well I want more power. So I will be building a 2.0 with a GT3076R.

I talked to Unitronic about their 830cc file and this will be what I go with.
Here are a couple of pics of the turbo.

[seanriv]

I think that 2871 still has some power in it. A 12 second 1/4 should be reachable. Congrats on going bigger though.

[pipe7284]

excellent choice for BAT set up...gt30r with a 2.0.