Jkay

I searched via Google for any instances of STS remote turbos lighting piles of leaves on fire, and altho I found thousands of posts praising the system, I just came up empty on the fire thing. Ah well. Not sure what you mean about snow?

Also could you be more specific regarding your "bad engine?" .. You sound extremely educated in the way of tuning (for instance you mention specific aftermarket fuel curve tuning and timing curve components by name) but are kinda vague as to what's up with your engine ... and you found a NEW A8 engine on eBay for $1800? GRATS! That's awesome.

Hope the shipping isn't too much.

I **think** you would be the first person, ever, in this forum to have an A8 with a "bad engine" ... they are normally very stable.

Lastly, as someone tried to warn you earlier, the Motodyne system, in it's only public viewing, made LESS horsepower than stock. It's my opinion that altho Motodyne has "a system" it is not a working system. People who have purchased this system have reported that there is no *instruction* as to how to install or use it; simply a box of parts which they bought for a lot of money and then could not use.

LemonA8

It still runs, but after 3 miles the fracture opens and coolant ends up in the oil. My a8 is a Lemon I don't think all A8's are this way? Wish i bought a differnt one is all i'm saying.

I understand enough to wanna try

LemonA8

a one legged duck will not swim in a circle if he turns his head underwater

BrianC72gt

Reality check. You gotta pass your emissions test, so a stand alone ECU is out of the question. Tech scratching head,"Hmmm why no OBDII signal?" A piggy back could work or you can do it all ...ahem...analog....rising rate fuel pressure regulator..modest boost..another box to intercept timing and retard as needed....messy.

Better still why not get your hands on the brain and harness for an RS6 ( V8 with twin turbo's, no??). They probably also have your air metering and fuel injector sizing all figured out, and then again they(edit) DID come with an automatic. I'm guessing they went with a MAP sensor. Still don't know if that will get you by in a strict emissions State like CA or NY.

But, hey once you have all that sussed, no worries, right? Its not like the transmision is a marginal ticking bomb... Okay, so now we are looking at an entire RS6 driveline.

Having done DIY forced induction, I can tell you this car is not going to be the easiest thing to do. Maybe a real modest setup with a rising rate fuel pressure regulator, but then there is still no guarantee that the ECU won't freak out. I would guess that the timing intercept won't be that easy either.

Ideally, if someone had already hacked the code, you could reflash the ECU with altered code to avoid any workarounds. That would be the cleanest, but by far the most technically challenging. There used to be an outfit, GMPCM, that had software for the average enthusiast to do just that with GM ECUs (prom swap)and PCMs (flashable) - and cheap too - but I don't know of one for VAG brains.

My suggestion would be mill the heads to boost the compression a little, find some better cams that will still work with the MAF sensor, play with the intake and exhaust and call it a day. Oh yeah, and a wet nitrous system....

LemonA8

For 6 psi the timing could stay exactly how it is

greenbird

I never said they were the same. A Kenne or Whipple will give better performance, especially as boost goes higher, and the packaging is very similar.

A Twin Screw has equal pressure on both sides of the rotors? WTF are you smoking? If it's equal pressure it's not building any boost.

LemonA8

Greenbird i'm not smoking anything. I know this to be true
A whipple , Lysholm, Autorotor and Kenne Bell apply. The rotor stack has the same pressure in the case that is deliverd to the manifold it's attached to. It is not a pump, it is a "true" compressor

greenbird

It is simply not physically possible. If the pressure on both sides on the rotors is equal then they are doing nothing more than a pinwheel in the wind.

Both are positive displacement rotational screw superchargers. An Eaton compresses the intake gas between the case and the rotors, a twin screw compresses between the two screws. They both compress the gas and raise the pressure.

Still don't know what you mean by "true", there are many different kinds of compressors. No one kind is "truer" than any other.

LemonA8

A screw compressor is a positive displacement machine that uses a pair of intermeshing rotors to produce compression. The rotors comprise of helical lobes affixed to a front and rear shaft. One rotor is called the male rotor and it will typically have three bulbous lobes. The other rotor is the female rotor and this has valleys machined into it that match the curvature of the male lobes. Typically the female rotor will have five valleys. The rotors never touch, but are timed by a pair of gears operating in a lubricated chamber, which is separated from the rotor chamber. With the 3-5 rotor combination, the male rotor turns 3 times to every one time of the female rotor.

The number of lobes on the male and female rotor will vary from one compressor manufacturer to another. However, the female rotor will always have numerically more valleys that the male rotor has lobes. Because of the number of male lobes, there are three compression cycles per revolution, which means that the resulting compressed air has small pulsations compared to a reciprocating compressor. By the time that the compressed air leaves the package, it is to all intents and purposes pulsation free.

Jkay

Ask anyone in the S4 forum about their 470hp cars.