LMAO, so you want to take the most unreliable E60 and add another 300HP to it? Sure, it should last about a week before and engine rebuild, and that's IF the trans, drive shaft, and diff can handle that much power. Also, $10k installed for the ESS kit would be MSRP, who pays retail?

 

How many people actually have an ESS supercharged 550? I would guess very few. There are literally hundreds of people with N54 equipped 135s, 335s and 535s running upgraded turbos, single turbo, etc. for years and thousands running various tunes with no problems. I think you are overstating the unreliability factor. The N54 is a very proven, stout motor and platform. Yes, there are issues w/ fuel pumps, injectors, etc. but those issues have been resolved for the most part and there are people running over 100K miles tuned on N54 motors with virtually no problems like this guy.

In the end, it doesn't matter. Both the 550 and 535 are great cars. I test drove both 550 and 535 6MTs extensively and wouldn't mind having either.

If you are talking about power potential, 535 just has much more b/c it benefits from the massive amount of aftermarket support and tuning experience of 135/335/1M, etc.

 

The link to the example you posted is interesting. I agree there is more available for the 535, thus it is more tunable. However, the mods you listed in your previous post are not on the car in the link, I highly doubt he'd get to that many miles pushing 600HP, heck at that point it wouldn't even be streetable. Sure if we're going to compare race cars, it's possible to slap an S62 in my car and supercharge it to around the 700-800 HP produced by the Gnassi guys in American Le Mans - but it wouldn't be a daily driver anymore and it would be far from reliable.
Ultimately my car must be as fun to drive as possible, and yet still be capable of being driven daily.

It seems Vishnew is having issues tuning the kit you mentioned: http://bimmerboost.com/showthread.ph...434#post403434

 

There are no real tuning issues specific to the Vishnu single turbo kit. Virtually all customers are happy with the results and you will find virtually no real complaints from those who have the kit. However, there are many pro and anti Vishnu people. Bimmerboost is a very anti-Vishnu site. The reality is, all of the "tuning issues" directed at the single turbo kit plagues ALL high powered N54s. Namely:

1. Automatic transmissions misshifting from 4th to 5th back to 4th - this happens with ALL very high powered N54s and is a function of the AT in the car as opposed to the single turbo kit or RB twin turbos, or specific tunes. ALL high powered AT equipped N54s have this issue.

2. Misfires on 6MT cars - this has been traced specifically to issues with dual mass flywheels and, again, occurs in ALL high powered 6MT N54s regardless of whether it is running the single turbo kit or upgraded twin turbos. Switching to a single mass flywheel resolves this issue 100%.

So, take these 2 main complaints aside and the reality is, there aren't truly any "tuning" issues with the single turbo kit.

While the car I mentioned doesn't have a single turbo kit installed, Shiv's development car, which has been beat on for like 70K miles being used as Vishnu's main test car, had the turbo kit installed at that point. It has since been beat on for tens of thousands more miles without engine failure - this with about 640 wheel horsepower and TONs of 1/4 mile runs, 60-130 mph runs, etc.

I think it's safe to say again that, while things like the fuel pumps, injectors, etc. have been problematic on N54s, the motor itself is VERY stout and has clearly been pushed to the limit for years and years with minimal evidence of catastrophic failure.

 

Also, FWIW, I think collectively, the 335 community is close to resolving the high powered N54 AT shifting issue. They managed to upload an Alpina AT flash to many AT equipped 335s and this seemed to greatly improve the performance of the AT in 335s.

It would not surprise me at all if one were able to get a download of an E60 Alpina B5 transmission program, it could just as easily be uploaded to AT equipped E60s providing great benefits to this platform as well.

Of course, I'm not too worried about this myself as I just picked up a 6MT E60 535i a week ago.

 

At the end of the day, you're right, they are both great cars. The issues will be resolved, but there will be added cost involved (like you mentioned the flywheel). I can't imagine a 600HP car using the normal single plate clutch either, and once you go triple plate it isn't streetable anymore. Years ago I used to race a Honda Accord in SCCA, it had an H22A with a large T34 turbo and it was fun to drive, on a track, the triple plate clutch needed for that power (360HP at the wheels) wasn't good for street use.

 

The sad part, I didnt even have enough time to tint the windows. I only made one payment on it before it was totalled. sad part, it only had 15,000 miles on it.

So no, never had the chance to do any upgrades or tuning to it.

 

I will work on getting some pics.

 

Ouch, that sucks. I hate to hear of a nice car getting ruined like that.

 

I think a lot of people compare a 550 to a 535 with a tune is because a tuner on cost a few hundred bucks. I doubt there are to many real enthusiasts that own an N54 with out a tune.

As far as buying either BMW, i don't plan to get to crazy with it. If I got a 535 it would probably just get a tune mild exhaust and a few other odds and ends.

A 550 would probably just get an exhaust. Both cars would get a limited slip differential. I can't believe they don't have one from the factory. Obviously to push buyers into M cars.

The BMW will only be a fun daily driver. I have a turbo LS1 93 Mazda RX7 to play with.