Some homebrew questions.....as my wallet starts to flinch.

[RR]

I haven't been keeping up. Last time I looked (a year back), the stage 3 kits were just showing up and were mucho $$. But now, homebrew seems to be all over.

I've got a 2000, 6-spd, with K04s. I running the original (pre-x) GIAC software (A-box).
Did my first FATs...tiny bit under 5 seconds.

1) George at MSP sugggested a Mustang MAF, 440 injectors, MBC, and TCD. Said it would work with my current software. Can A boxes be wired to use the alternative MAFs?

2) I get the impression that he's talking about running MBC only. Isn't spinning the snails all the time likely to add wear + tear, add heat to intercoolers when not needed, and hurt gas mileage?

3) Is there a better way to do this?

4) Can my current setup be tuned for better power with Lemmi?

I've spent about a month STFA...and I don't see the answers.
RR

[Ochlockonee]

1)Ford has never used a bosch film style maf, so no. I suggest an RS4 or BMW 540 maf 83mm housing for k04s. You have to keep your stock maf element though.
2)The snails spin all the time anyway. The wastegates are opened by boost, not vacuum. I have occasionally run into compressor surge while climing hills on the highway when I had an MBC, but rarely. This can be overcome for the most part by using the mbc in parallel with the N75 and a TCD installed.
3) Aside from the boost control suggestion above, no. This setup is the stuff. You could try an EBC if you like.
4)Problably. Installing a 5 bar fuel pressure regulator and raising boost to ~16 psi @ redline is really the next step in power though.

[RR]

all that much. Am I missing something?

RR

[Ochlockonee]

He really did a great job of documenting it for us.
His sig has a link to his photobucket pics which is a wealth of chartsngrafs. Many of them are of that setup with fats times. The archives are also full of his posts about it. Try searching for 3- fats or 5 bar fats and filter with his uid.

[RR]

On Doc's site, the timing starts off low and marches up to about 20 degress.

Mine goes to about 3-5% when it's under load and stays there. Here's a log:

Group A: '003
Engine speed Mass air flow Ign timing
TIME g/s deg
STAMP /min g/s °BTDC
0.01 3320 96.42 22.5
0.29 3400 101.89 21.8
0.58 3520 103.31 24
0.88 3600 127.94 21
1.18 3760 176.44 13.5
1.48 3920 206.83 4.5
1.8 4080 223.06 2.3
2.09 4240 229.44 1.5
2.41 4400 224.28 0.8
2.73 4560 223.61 2.3
3.05 4720 231.94 3
3.38 4880 238.61 3
3.72 5080 240.64 4.5
4.06 5200 247.64 4.5
4.4 5400 254.78 3
4.75 5520 263.28 4.5
5.11 5680 268.22 4.5
5.47 5840 275 7.5
5.83 5960 275.19 4.5
6.2 6080 275.69 4.5
6.57 6240 275.31 4.5
6.95 6360 275.31 6
7.33 6480 276.83 5.3
7.7 6640 279.17 9.8
8.08 6720 255.5 0.8
8.46 6680 12.86 45.8

Is something wrong here?

RR

[InFlux]

If you don't mind the 'surging' effect of the boost, you're really okay. I've been running MBC only for about 10K miles with no issues. A homebrew setup will give you a lot of bang for the buck, and as I and anyone who has ridden in my car will attest to, can be quite smooth when tuned properly.

By the way, I'm peaking at about 22-23 psi and tapering to ~20 at redline :-)

[PSmalls::DoggieStyle]

1.) You'll probably be best off with a RS4 MAF housing, but there are several options. 440cc injectors, MBC, and TCD are good ideas. You may want to upgrade your software from S (I assume you have S since you said pre-X) to X for your homebrew setup.

2.) I, and many others, run MBC only. It doesn't really put more stress on the turbos. I get very good gas mileage, doesn't negatively affect that at all. Some complain about drivability with MBC only, but personally I love how mine drives and don't have any complaints.

3.) There are several different options re: injectors, fuel pressure regulators, MAF housings, intake setups, etc. This is the beauty of homebrew, can piece together whatever parts you want basically. One setup isn't really "better" than another, but there are some setups that have shown to be more proven and more widely used than others.

The most common is probably RS4 MAF housing, Greentops injectors(~440cc@3bar), 4bar fuel pressure regulator, and stock airbox (modified to fit bigger MAF housing) with stock filter. I run a similar setup, but use 38# Delphi injectors (~397cc@3bar) and a custom 4.7bar FPR from VAST Performance instead.

4.) Lemmi can definitely help with a homebrew setup. I highly recommend having software with logging capability (VAG COM/ECUx) and access to Lemmiwinks.

All these answers are definitely in the archives, but at least you tried searching.

[Imola_Tip_Soul-Ja]

your AFR @ the MAF/ECM. Specifically MAF voltages, because they have a direct impact on the fuel maps that your S4's ECM will utilize under specific conditions (idle, part throttle, boost, etc.).

The ability to FINE TUNE (tweak) specific points (by MAF voltage & RPM) in your fuel curve is ALWAYS better than the GROSS FUELING approach of Lemmi(% changes to the OVERALL fuel curve that don't address specifc points in the fuel curve that could yield more HP, or Torque through spot tweaking).

Just some additional info to digest. After you add the wideband 02 sensor, and fuel management software, your S4 should be a happier (and healthier) car.

[djillusion]

any reason not to use autospeed's or jacob's MAF housing instead of the RS4 modified one?

[mbox]

you will drive yourself crazy b/c the numbers will never match up correctly, especially IDC's and MAF voltage. The only way to truely compare logs is to run the exact same setup, then compare. Trust me, I tried.

Also, make sure you do significant logging / testing before playing around with Lemmi b/c, as I'm sure you already know, you can do serious damage to your car.