A few weeks back, I placed an order with PES for the 30v Supercharger Kit. I was told that the kit would be available for shipment in about 4 to 8 weeks. A few days after I placed the order, I unexpectedly received a call from Tony Ricci at PES. He wanted to know if I would be willing to come down to NJ to have the prototype Supercharger Kit installed on my fwd 30v for final chip tuning and dyno testing. According to Tony, they had been flooded with requests for dyno numbers, and he needed a fwd to accomplish the testing.<p>I got to Tony’s shop at around 11:00am on Friday. Tony and Mike (the engineer on the project) began installing the supercharger at around noon. 3.5 hours later, the kit was installed, making my A4 the first vehicle ever (besides the PES test vehicle) to have the supercharger kit which I thought was pretty neat. Obviously, Tony and Mike were very familiar with the install, so they worked quite efficiently. For someone else to install, it would definitely take a lot longer. For someone who was somewhat handy, it would probably take an entire day. For someone who is not handy, get professional help.<p>Due to the lengthy nature of this post, I separated it into 3 parts: install, drive, and dyno testing.<p>INSTALL<p>As far as the install itself, it was very neat to watch. The following should give you a general idea of what the install is like. The job started by removing all of the plastic shrouds that cover the engine. The air filter assembly is removed, as is the throttle body and intake tube that connects to the back of the intake manifold. A number of vacuum tubes, plug-in connectors and hoses were removed as well. As Tony and Mike removed the pieces, I noticed how just about everything either “clicked”, “snapped” or “plugged” into one another. This makes the install much easier.<p>Next, the screws holding the fuel rail down were removed. This allowed for the removal of the fuel injectors, which was a very simple process. It was just a matter of unplugging the electrical connections and pulling the injectors out.<p>At this point, the new injectors are put in place. The larger injectors that come with the kit are slightly taller than the stock injectors. PES provides spacers to lift the fuel rail into the proper positioning so that the larger injectors are secured properly. A thin application of Vaseline was used around the O-rings of the injectors to help ease them into the proper position. After they are set in place and secured, the electrical connections plug right in, just like the stock injectors did.<p>A beautiful custom fabricated piece that took care of positive crankcase ventilation was attached toward the back of the intake manifold. If I remember correctly, in the stock configuration, this “port” recirculated crankcase gasses right back through the intake tube (it was actually integrated into the intake tube itself) in the stock configuration. However, with the pressurized configuration, this presents a problem. Therefore, PES custom fabricated a system that addresses this issue. I am not too certain of the technicalities of the system, but it seemed to be very well thought out. <p>Toward the back of the engine bay where the supercharger sits, there are two bolts that need to be cut off. This was accomplished with a Dremel tool. One of the bolts did nothing, the other secured the fuel lines to the firewall. The fuel lines are tie wrapped out of the way. The removal of the bolts is necessary to provide clearance for the supercharger when the engine torques back. It is simply amazing how tight this installation is! To give you an idea of how anal-retentive the guys from PES are, they actually searched for (and found) a bottle of red touch up paint to cover the bare metal where the bolts had been cut off! <p>The next step seemed a bit intimidating to me at first, yet proved to be extremely simple. In order to attach the lower tension pulley, much of the front end of the car needs to be somewhat dismantled. What I thought would be a difficult task took about 15 minutes. The process goes like this. There are a few tabs on either side in the wheel wells which are removed. These tabs are not reusable, however, PES provides replacements (which are reusable). Then the two black trim pieces, where fog lights are often located on other cars, are removed. There are two large bolts that hold the bumper cap on. The bolts are removed, and the bumper cap comes off the car relatively easily. Each headlight assembly is unplugged then removed quite easily with 3 screws each.<p>Next, there are about 10 bolts which hold the radiator sub-assembly to the frame that are removed. The nice thing about this is that the radiator sub-assembly does not need to be removed. That would be a big pain with all the hoses and connections. Rather, the assembly simply pivots forward, which is all that is needed to accomplish the next step, which is to install the tension pulley. This is very easy. One of the bolts holding the alternator in place is removed. The pulley assembly simply slides right in its place and is bolted in. Very slick.<p>There is a similar pulley assembly which is attached to a mounting point at the top of the engine. This is also a very slick piece. It serves two purposes. On the front side, it provides the top pulley. On the rear side, it provides a mounting point for one of the supercharger mounting brackets. <p>There are two bolts which hold the heat shield for the exhaust manifold in that are removed and replaced with studs. These studs are used to secure the lower mounting bracket for the supercharger. At this point, the supercharger can be secured. First, the lower bracket is secured by bolting it on to the studs. Then the top bracket is attached to the mounting point previously described. Together, the two mounting brackets provide a very rigid mount. <p>The next step is one which I couldn’t follow by simply watching (they were going to fast for me to follow). This step involves the replacement of all the vacuum tubes. This is one area which really necessitates good directions. Also, the variable length intake tube system is disabled. I was told that since the supercharger creates a pressurized system, the need for the variable intake lengths was not necessary. Not sure which ones were enabled, but I assume they were the shorter tubes.<p>A few hoses, including one that connects to the piece for exhaust gas recirculation, were connected to the supercharger assembly. An intake tube is connected from the supercharger to the intake manifold. There are a few more connections which are made, including one from the bypass valve back to the supercharger. The serpentine belt is then put in place.<p>I may be forgetting something, but I think that is just about it. The radiator sub-assembly is bolted back on. The headlights are screwed back in, and the bumper cap is bolted back on. That is pretty much it. Now, on to the drive.<p>DRIVE<p>After everything was installed, the engine bay was checked for any loose tools hanging around. The OK was given, and the key was turned. The engine sounded rough for about 3 or 4 seconds until the fuel system pressurized, bringing the new injectors to life. After that, the engine ran smoothly. However, there was a decidedly different noise at this point. One can easily hear the “whirring” noise of the supercharger. At first, it sounded a bit strange to me, not having had any preconceived notion of what it would sound like. As time went by, I got used to it. <p>We drove around for an hour or two, which was incredible. Tony drove while Mike was checking all sorts of readings on his laptop that was plugged into the OBDII port on the underside of the dash on the driver’s side. I don’t even know where to start, as the whole thing was incredible! I guess I will start by giving you my impressions of the drive I took alone…<p>I got in the car, put it in first and let the clutch out. I applied throttle, and the car launched aggressively. The first difference I noticed was that I was going to have to change the way I drove the car! There is a LOT MORE torque available WAY DOWN LOW in the rpm range. So much so that I spun the tires a little bit just trying to normally launch the car in first! Whereas before I could get away with letting the clutch out, then pushing fairly deep on the throttle, no such luck. There was so much torque available, all I needed to do was feather the throttle, and the car took off with authority. It almost felt like the car weighed half as much. It felt REALLY LIGHT. I shifted from first to second, let out the clutch and applied throttle. The car accelerated so effortlessly. It was great. <p>Since I was feeling this out slowly, I was taking it quite easy. Finally, I decided to let loose a bit. I stopped at a light. The light changed, and I took off in first gear light. 1000rpm… 2000rpm …3000rpm …4000rpm …WHEELSPIN!!! OH MAN!!!! I had a huge grin on my face. This car was not just fast, it was VIOLENT in first gear. In fact, earlier in the day, Tony was getting wheel hop in 1st gear at higher revs with FOUR OF US IN THE CAR! Now, remember that my car is fwd (with Z-rated rubber). In a Quattro, this thing would hook up and take off like a bat out of hell in first gear!<p>I smoothly shifted into second gear and drove normally once again. I had to gather my thoughts! I couldn’t believe that this was the same car I arrived in. I got to another light on rt. 202 in NJ and decided to see what second gear felt like. 1000rpm …2000rpm …3000rpm …4000rpm …5000rpm …6000rpm …shift to THIRD GEAR … on-throttle … YIKES HOLD ON!!!!! 4000rpm … BRAKES!!! It all happened VERY quickly! This car is FAST. <p>Two things really hit me on the 2nd gear 3rd gear run. First, it was amazing how quickly the revs built. I wound through 2nd gear so fast it was ridiculous. The second thing that really hit me was how STRONG the 2-3 shift felt. As soon as I hit 3rd gear and got back on the throttle, it felt like someone let an elastic band loose. I shot out of 3rd gear and was going way too fast way too quickly! It seemed that the 2-3 shift put the car right in the rpm range where peak torque was available.<p>I was having an absolute blast. I found myself just cruising along in either 2nd or 3rd at about 3000rpm and just hammering the throttle. In doing so, I was IMMEDIATELY greeted with VERY healthy doses of acceleration. I had always heard that this was the beauty of a supercharger, and could finally confirm it first-hand. There is absolutely no waiting. Throttle response is instantaneous. Even better, the driveability was unchanged. The rush of power was not at all abrupt, which was something I was initially concerned with. Other than the strange whirring sound coming from beneath the hood and the tremendous increase in torque, you wouldn’t even know that the car was toyed with. <p>One thing is for sure. This car demands the sport package or an aftermarket suspension. I couldn’t even imagine how sloppy the car would feel without it. <p>Earlier in the day, much driving was done as well. There were always 3 or 4 of us in the car. Most impressive was how the car accelerated uphill, at relatively low revs, in 5th gear with FOUR OF US in the car. On the highway, we went from 80 to 130 awfully quickly in fifth gear. All of a sudden, we all felt a hesitation. No one was quite sure what it was until we realized that we had hit the 130mph speed-limiter (which they thought had been removed)! The car felt like it had a LOT more to give. Actually, being in the back seat, I was GLAD that the speed-limiter was in place. I feel a whole lot more comfortable when I am the one doing the driving! Later, the speed-limiter was removed. Luckily, it was drizzling on the way back, and we played it safe.<p>I just can’t tell you how different the car felt. It was just awesome. I grew to love the whir of the supercharger, which sounded a bit strange at first. <p>DYNO<p>The reason there were four of us in the car at one point was because we were all headed to complete the dyno testing. Everyone was very eager to see what the car would test at. After many months of work, I could tell that Mike and especially Tony were both very anxious to get some numbers. Garret, who was doing the software, was also very eager so that he could finally get Tony and Mike out of his hair! For Garret, this had been a painstaking process, since ALL the software had to be remapped due to the special nature of the kit. Since the car was using larger injectors and taking in so much more air, the ECU’s factory parameters simply didn’t know how to deal with it.<p>Tony rented dyno time from a place in NJ called Crazy Horse Racing. They had what must have been a brand spanking new Dynojet which was installed into the floor. The previous dyno testing I had done was at Rally Motorsport, which had the dyno above the floor - which necessitated driving the car up on a ramp. The setup at Crazy Horse was great. All you needed to do was drive the car onto the rollers, tie it down, and viola!<p>We did about 8 runs. Garret, the software engineer, tweaked the chip in between runs. The last couple of runs were great, yielding a chip that gave a hp figure of 280hp (using wheel hp + 15% to get engine hp) and a torque figure of 262 lb/ft (using same formula). These were the numbers that Tony and Mike were looking for, and they left the shop quite satisfied that they finally had the hard facts on the hp and torque numbers. The torque curve was really flat, showing that there were gobs of torque available throughout the whole rev range. It was freaky, almost looking like the stock torque curve of the stock 1.8T (except lots more of it, of course). The hp curve was VERY smooth as well. I am sure the graphs will be posted shortly.<p>We also tested to see whether or not the speed limiter was removed. The car hit 145 fairly effortlessly on the dyno, showing that it was, in fact, removed. It’s hard to say what the car would top out at, but Garrett guessed about 160 to 165. The dyno can’t really show you since there is no wind resistance.<p>SUMMARY<p>I would have to summarize by saying that I was more than impressed with the supercharger kit. I really wasn’t sure what to expect. However, I did know what I wanted. I wanted to see huge improvements in performance while maintaining driveability, and that is what I saw. This is still my daily-driver, and I need it to act like one when I want it to. With the supercharger in place, the car is simply transformed. I guess an added 90hp tends to do that! However, the real story is torque. There is lots of it, and even more important, it is almost always available. This is what makes it feel so great. For those of you who know how the 150 lb/ft of torque in the 1.8T feels like a whole lot more because of where it is available…you know what I am talking about.<p>The other thing I have to say is how impressed I was with everyone involved in the project. The guys over at PES did a great job. They were extremely detail oriented, and it really showed in the kit. And that was only the prototype! They were also very, very careful with my car. I have had my car scratched while getting my oil changed! The PES crew installed a supercharger kit, then took it off and put all the stock pieces back in the car without a scratch. They also showed great care in the way they went about everything. From the way everything was carefully tie-wrapped to the way they put the red touchup paint on the exposed metal where the bolts had been cut off…their attention to detail really showed. The other thing that was apparent was the pride they had in their work. Mike would often hold up one of the custom polished-aluminum pieces he machined and look at it admiringly. In fact, someone else had gotten their hands on one of his parts and put marks in it from a pair of vise grips or something. He pointed the marks out in disgust, saying “Look at this, can you believe someone did that to this beautiful part! I designed it so that it is easy to tighten with a wrench, and someone stuck a vice grip on the end!” He was truly disgusted!<p>Well, I can’t wait until the production pieces are in! It was awfully hard driving off without the supercharger in place. I think Mike said it best after taking the supercharger off. He said “sorry we had to neuter your car”. <p>By the way, the “neutering” only took Tony and Mike 1.5 hours, at which point the car looked exactly the way it did when I drove in.<p>Also, I should mention that I have no connections (aside being a customer) with PES. Since I have a fwd A4, my car seems to be in demand by the tuners who don’t have access to an all-wheel drive dyno (so if I had a Quattro, I wouldn’t get involved in all this cool stuff!). When Tony called and asked whether or not I would be interested in testing the supercharger, I jumped at the opportunity. I was involved in a similar fashion when Wetterauer was developing their chip, and these trips to NJ give me a good excuse to visit all my friends in NYC. <p>Watching the development of these aftermarket products is very cool. Not only do you learn a lot, but it also gives you much more (or possibly much less - depending on the circumstances) confidence in a product by seeing how it is developed and engineered, as well as by seeing the people behind the product. I think that anyone who had been in my place would have been very impressed. Tony and Mike have so much enthusiasm and pride in this kit. Don’t take my word for it though. Give them a call and see for yourself. In fact, we were all starving for some food on Thursday night. We were all set to go when someone called with questions about the supercharger. They were on the phone with this guy for at least a half-hour answering questions! I thought I’d never eat!<p>I hope to have the production kit installed as soon as the final production pieces are shipping. If anyone sees a red 2.8 that has an unfamiliar whirring noise emanating from under the hood…you’ll know it’s me. I know the BMW M-Coupe driver I ran into was VERY surprised that an A4 sedan was overtaking him at full throttle on Rt. 202! ;-)<p>P.S. For those who want to see the dyno graphs, I believe Tony will be posting that information soon. Also, we have tons of pictures of the install as well as of the dyno testing.

An M3? Perhaps. But that M coupe is kind of LIGHT, which is more than we can say for the M3 or A4!<p>Enjoy! And hunt down some Z28's for me while you're at it.<p>:)<p>Chris Gröos

Very impressive and well written, Michael.<p>Kinda makes me wish I had gotten a 2.8! :-) <br>Good luck with your final installation.<p>Jim<br>'98 A4 1.8T qms/Neuspeed

Geez Michael,... I am truely jealous now. <br>You know there will be a line waiting to ride in your A4 at the next NE A4 meeting! <br>Fantastic write-up, BTW!<p>Cris<br>

Check carpoint. The M-Coupe weighs almost EXACTLY the same as the A4. However, it is down 40 hp and about 26 lb/ft of torque. Also, I doubt the torque is available where it is on the supercharged A4. Nothing can be that flat...wait until you see the dyno graph.<p>Even Garret, who is very big on BMW's and does all sorts of chips for them, said that it would probably take an M3. And he came to this assumption based on his experience with 4 of us in the car!

(nt)

(nt)

Here is a link<ul><li><a href="http://carpoint.msn.com/VIP/specifications/1999/BMW/M_Coupe">M Coupe specs on MSN Carpoint</a></li></ul>

Great write-up! <p>What kind of replacement air intake system gets used? I know what you mean about the sound of a supercharger having installed one on my last vehicle (twin-screw type). I had a K&N conical filter that allowed ALL of the "gear"-noise to be heard...sounded great then: like you had gear driven timing, but louder!, but I like my purring 2.8 quiet...<p>Hmmmm. Almost makes me glad I got the tiptronic...won't have to cry as $5000 flies out my wallet...<p>steve<br>

Chris:<br>appreciate your candor--i feel like you are the resident ombudsman (spelling ok--mr english teacher).<p>question: (not a flame)<p>i was at bimmer.org: they are not nearly as animated as the a4 site. (read boring)<p>do you ever post over there?<br>whats the response like?<p><br>1996 a4 2.8 qms <br>

Impressive! I betcha that thing spins like hell with a FWD! :) You said you used a 15% loss conversion to get 280hp, so I guess that puts you at around 240ish to the front wheels..is that right?. I think a stock M3 puts out around 206-210 to the rear wheels, so you should be able to toast any stock M3 out there, and probably the chipped ones too...uh oh. I guess I'd better call Active Autowerke and get that turbo kit ;) <p>Brad Franklin

Here is a pic<p>Steve S.

I can't ever spell that word either!<p>The bimmer.org site isn't that great. That's why I hang out here. You guys know your stuff and I can get answers on stuff like tires, suspension, general auto stuff. And it's nice to band together and bag on the Acura's and Lexi of the world. :)<p>I met about 5 of the guys from bimmer.org, and we do at least 2 road trips per month together. We all find a twisty mountain road and attack it with our M3's. Kind of cool.<p>:)<p>Chris Gröos

(nt)

..

Man I'm feeling feisty today! ;-)<p>Sorry Chris but it looks like the weights are about equal.<p><p><br>

It's really far back on the door. I realize that the window makes this necessary, but I'm thinking from a driving perspective, the placement is bad. I don't think a driver can look at this mirror without turning their neck to face it, especially a short driver.<br>

Because you know the fat ass BMW owner weighs at least 300 pounds

Your calculations are correct. Wheelspin is only a real problem in 1st gear. You simply can't give it full throttle. However, 2nd gear and on work very nicely. The Toyo Proxes T1 with their soft compound help out quite a bit as well. <p>Also, aside from the all-out performance the supercharger provides, it also makes everyday driving a lot more fun. There is so much usable torque available down low, that it makes rowing casually through the gears a pleasure.<p>As far as the fwd vs. quattro, there is no doubt that a quattro would help take better advantage of all this extra power. Also, with quattro, you would only be adding an extra 22.5 hp per wheel, versus an extra 45 hp per wheel in the fwd. This puts less stress on the vehicle. <p>However, it is a testament to the capability of the fwd to perform so solidly with 280hp. If anything, it certainly shows how easily the fwd should be able to handle the stock 190hp. In fact, torque steer was still kept to a minimum even with all that additional power. It was slightly more evident than stock, but not all that much different.<p>Mike - not a famous actor...yet ;-)

But supercharge the M's 3.2 litre and goodnight, Irene. %^)

280hp A4 Quattro + Supercharger = approx. $37K<p>240hp M3 = approx. $42K<p>How about a supercharged Passat 30v! Now there's bang-for-the-buck...<p>Mike

Thanks for taking the time to prepare that writeup! It would make a good addition to the FAQ, with possible updates later when the production kit comes out.

Might want to check the December issue of "European Car" for the changes done when Audi upped the power from 150 to 225 HP on the TT. Was lengthy, also! Would be worried about driving this much power thru stock engine internals, clutch, and driveline.<p>Best of luck - hope it DOES hold together.<br>

I assume that you noticed, but this mod. was done to the 2.8 V6, where the TT engine is the 1.8T. EC's comments on raising horsepower apply to the 4 cylinder engine with stock hp in the 150 to 180 range.<p>However, it is my opinion that ANY increase in horsepower over stock, in ANY engine, will have some effect on engine wear, life, etc. (assuming the extra horsepower is actually used). It might not be significant, and the engine (and trans.) might be able to take it for a good, long time, but extra HP means extra forces generated inside the engine (and rest of drivetrain), which can't help be transmitted to extra wear and tear. The owner of a modified vehicle just needs to be aware that there could be consequenses to the mods., and justify the tradeoffs in his/her own mind. (If the engine will still go over 100K miles without complaining, and the owner plans on selling before then, who cares?) Of course, using this logic would say to some that the best thing to do would be to DEtune your stock engine for longer life. Yep, it would probably work, but I don't think many people, including me, would consider this (and it would probably void the warranty, too!)

but the M3 has a WARRANTY and you just voided yours.<p>besides, no shortage of superchargers available for BMWs <br>

.....and thats with the Audi owners head in it!

.........first WETT dynoed you, then PES........jeez, what's next? Is someone going to want to strap a jet engine on to your car?<p>All the same, I'm glad you try the new performance stuff on your car first! :-) As someone else already said, hope it all holds together! :-)<p>.....and don't forget.......that 5k would have been a nice down payment on an S4. Add a WETT chip for 325 hp!<p>Rick<br>

The S4 is going to have about the same power so I'd assume the changes made to the S4 would be nice for the A4.

What did they upgrade?...I know the brakes are different, but what else is needed to handle 265 bhp?<p>Steve S.<br>97 2.8QM<br>

Extra power means extra heat, and over time, heat is what causes the wear and tear. HOWEVER, this is something that, as you mention, is a cummulative thing.<p>The reliability of this kit, or any kit with large hp increases for that matter, will depend greatly on how it is driven. If you are constantly slamming shifts at redline, you are more likely to have a problem than if you learn to drive it fast, but gently at the same time.<p>Tony Ricci really drove it well. He shifted quickly, yet gently. I think it all comes down to common sense.<p>From the careful design and engineering that went into this kit (especially the software), I fully expect it to be reliable over the long-haul. I guess we'll just have to wait and see. I can tell you one thing, I am going to have a blast finding out! ;-)<br>

I think that one of the main reasons it is appealing to me to have a supercharged A4 (other than performance) is to have something unique. <p>There are quadrillions of M3's here in the Boston area. In fact, I think that to get into Boston University, it is required that you own (or lease) an M3. <p>I wanted something special and unique, and that is what I will have. <p>As far as superchargers go for the M3, yes, there are many available - but they push the higher price of the M3 even higher. Now you'd be talking about a supercharged M3 that was about $10K higher than a supercharged A4. Hey, if you have the money to blow, why not...but $10K is a big chunk of change for most.

5' 7" and I had no problems whatsoever with the mirror placement while driving it. Then again, I can't say that people in the 5-ft range wouldn't have any trouble as it is kinda far back but I think it is more related to the design of the car (i.e. it is not really far back but only looks that way in conjunction with the doorlines).<p>The thing that really gets me going is the fact that the windows don't go down all the way. They stick up just enough (1/4" or so) to dig into your arm if you rest it on the door. That is a pretty annoying design flaw in my book. However, since the car ran like it was on rails, I could possibly forgo such an annoyance :)

Are the tranny components beefier? Nice word "beefier". Are the half shafts larger? CV joints larger? clutch plate? clutch itself? Wish we knew the answers to these questions...cause then MichaelB could start to implement them. :-)<p>Steve S.<br>97 2.8QM<br>

First of all, at least 95% of the people looking to purchase a supercharger kit are going to be those who own a Quattro. So let's use the Quattro as an example.<p>That being said, consider that the added stress put on each wheel on a Quattro is 22.5 hp with the supercharger kit. This brings the wheel hp at each corner to a total of 71.25 hp. <p>If you consider that the FWD handles 97.5 hp/wheel in STOCK configuration, the Quattro should certainly be able to handle 71.25 hp/wheel in the supercharged configuration. This is assuming that the driveline is similar up front of course. Also, the supercharger kit, while producing torque instantaneously, is making about 30 lb/ft. less torque than the S4 will be making at its peak (around 295 lb/ft), so it isn't adding quite as much torque as the S4.<p>This is really not much different than 1.8T owners pushing their engines up to the 200hp - 235hp+ range. People have been running chips and turbo kits with about the same percentage increase in power for a number of years without negative effects. In fact, the supercharger is only pushing 5 psi versus an additional 12 - 14 psi on the turbos.<p>I checked the supercharger kits available for the Porsche Boxster and BMW's among others, and none of those kits came with any driveline parts or engine internals. Some of these other kits have been around for a long time and are from very reputable firms.

(nt)

Michael, I may be a little bit more sensitive to this issue of "can the car take the mods"? Remember, I am currently fabricating two pieces to reinforce my subframe due to stress cracks caused by the aftermarket rear sway bars. I am living this issue. Again, I hope that nothing goes wrong....I would just be the guy that beefs up other stuff as well. I still envy your power...remember I only got the 12V :-)<p>Steve S.<br>97 2.8QM<br>

Your statement about quattro doing 71.25 HP/wheel is true only under ideal circumstances, such as when there is no wheel spin.<p>But, imagine if one end of the car has no traction. The other end will suddenly get most (all?) available power to the two wheels with traction, due to the torsen. If this were an untouched 2.8, then the amount of HP at each wheel is somewhere in the neighborhood of 190/2 or 95- HP at each driven wheel. The supercharged 2.8 would be giving 285/2 or around 142.5- HP to each driven wheel.<p>These numbers are obviously off since I don't think the torsen can send 100% power to one end of the car. But, for arguments sake, I think the increase in power to these two driven wheels is significant. And what happens when only one wheel has traction?<p>Another problem I have with this argument is that you are expressing the increase as being distributed equally four ways. However, you have only one transmission, and one center torsen differential. These components are going to feel the change as much or more than anything else. What happens at the wheels is the least of your worries.<p>Drew S.<p>P.S. I hope the supercharger is a terrific success. I think it would get me into trouble with Johnny Lawman. ;-)<br>

Since I am throwing the supercharger into a fwd A4, I am obviously not overly concerned. If I was going to drag race the car or constantly be running it hard, I'd be more worried. <p>One thing is for sure. If someone came up with a supercharger kit that included different pistons, clutch, transmission, CV joints, etc., no one would buy it! With all the money it would cost, they would buy an S4 for less.<p>A recent European Car magazine article focused on the negative aspects of modifying cars. It focused quite a bit on the 1.8T chip and how awful the results were (in their opinion - not mine). It also mentioned how it would probably affect reliability. Well, do you think this will stop folks from chipping the car? I doubt it. With any mod comes additional risks. Either you accept these risks or you don't.

Drew, recall that the EDL and ASR systems will brake a slipping wheel in both the Frontrak and the Quattro, so that it equalizes the torque side to side (of the open differential).<p>With that in mind, you'll never have more than 114 lbs-ft at any one wheel. (BTW, I believe that torque is more important than HP in this example.) For the Quattro, I beleive the Torsen diff allows a maximum F/R split of 67% and, as such, the maximum torque load would be less than a front-driver.<p>Of course, in any case, more torque and power will result in greater wear. Whether you're willing to accept the risk is up to you.<p>Jim<br>'98 1.8T qms/Neuspeed