blslhi

1) How different is the rs4 airbox than the s4s. I know the openning on top of it must be bigger to house the larger mass air flow sensor housing, but what about the bottom half. Also does it use the stock filter?

2) Why would I want to change to Bosch Mass air flow sensor when mine is the more reliable hitachi? The APR kit I am interested in seems to want to use Bosch.

3) Anybody here ever blow a head gasket due to too much boost?

4) Any stage III people running 20lbs of boost using the stock throtle body boot?

5) Should I really do this? Wife has given me the okay. I always thought if wife gave okay I would do it, now to be honest, I am scared for my car and most importantly my wallet. Thanks for the answers.

davenew

1) The RS4 airbox upper half has a larger hole for RS4 MAF. The bottom has an extra intake opening with a flap. Similar to 2.8L cars, it's designed to open in upper rpms to let more air into the box.

2) Yes, APR uses the larger RS4 bosch MAF. Who cares about reliability? You can buy a rebuilt bosch unit (from a dealership) when it fails every 3-4 yrs for $100.

3) Headgaskets are damaged mainly by knocking while under boost. THe motronic is pretty smart and the software is great. The most likely way to blow a headgasket is to use 93 octane fuel with software designed for 100 octane.

4) You kidding? It barely holds with oem pressure.

5) If you enjoy spirited driving it will be worth it. I'll say more after I get mine installed. The bad thing is one mod leads to another. I'm afraid after getting more power I'll "need" more braking..

JasonS4+Festicle

blowing one though.

4. Probably not a great idea - get an APR bipipe and call it a day.

5. Yes, you should but you might want to consider making your own "home brew" kit - or at least consider AWEs.

PSmalls::DoggieStyle

1.) The main different is the bigger MAF to airbox hole.

2.)I know I wouldn't want to go from my Hitachi to Bosch. The reason the APR kit wants you to do that is because RS4 MAFs use a Bosch MAF sensor (All RS4s had Bosch MAF sensors).

3.)None that I know of. You definitely won't blow a head gasket running APR stage 3 since they don't request crazy high boost.

4.) I'm sure there is *someone* doing it, but does that make it right? If you are going to shell out all this money for a stage 3 kit, why not spend a little more for piece of mind?

5.) I went through the same thing as you recently, second guessing my decision to go through with it. In the end, I justified to myself that it is worth it if I will enjoy my car that much more and will keep the car for several years longer at least.

JasonS4+Festicle

the ECS Stage III kit - they both fit....

Looks like that's the next mod.....

Have you looked into brakes? If so, what do you think about the ECS kit?

davenew

A coworker bought a new G35 recently. I figure even after buying stage 3 stuff I'll have twice the car for less than he spent for his new car. Does that make sense?

PSmalls::DoggieStyle

I have looked into brakes. Then I see the price and stop looking. I'd be more than happy to accept donations

PSmalls::DoggieStyle

Heh, makes sense to me

JasonS4+Festicle

the guy I bought them from sold them.

The other option was the 4 piston Alcons but they are much more expensive.

I like the pad selection offered for the 993 calipers.

Anyway, I just need to decide on a color - I test fit over a set of red and they were sooooooo dirty. I don't think I could stand that.

I'm thinking black or silver. I'd get silver in 1/2 second if I did not need to pay more for the same exact caliper.

PSmalls::DoggieStyle

Plus, they are relatively cheap to maintain (replacement rotors in comparison to what you have now based on your discussion with Jeff Doyle on AW) and, like you said, there is a nice selection of pads. How much more is silver than black?

Regarding the color, I'd go with silver or black as well.