I'm gonna act like you're not being smug towards me w/ the little popcorn smiley

Turbo
Turbo manifold
Intercooler (depending on HP, but not always needed)
Custom intake piping (easier part, hence why I laugh at $$Dinan$$ $300+ intakes)
Boost controller (manual for $20, electronic for $200)
Fuel pressure regulator
Higher volume fuel pump (depends on HP demands) if the stock pump isn't sufficient
Tuning via either a piggyback (choose your weapon) or custom software (it's getting cheaper and cheaper nowadays, some doing if from home via laptop)
About 5-8k laying around, which is still a decent amount, but the gains will be higher

I've driven a custom, single turbo'ed E34 540i w/ an M62 swap, Unichip piggyback (same system I used on my Tacoma) running around 450hp. For the case of my 740iL, VFEngineering makes an centrifugal S/C system for around 6k, but it's very limited on power, not intercooled and the sweet spot of the power (like most centrifugals) is in the higher revs. I've been considering going something like www.ststurbo.com, either single or dual turbo so I don't have to deal w/ having custom headers made, not to mention the added heat to an already hot and prone-to-overheating engine bay in the V8.

As I said above, check over on the FI forums on the boards I listed above. 3 series and I6 equipped 5 series BMW guys have been throwing boost at the I6 LONG LONG LONG before an X5 ever rolled off the assembly line. This might be an extreme example, and he's since rebuilt the motor, but it shows what just ONE person was able to get from a dinky little 1997 2.8 - www.bmwturbo328.com Mind you, he got like what, 600hp and countless 1/4 runs before he even had a single issue w/ the motor...and that's a 2.8!!

Point is, the I6, while less power in stock form, is for more reliable and tuneable than any V8 for the simple fact...there are thousands upon thousands of I6 owners who modify their cars vs V8 owners. Does reliability go down as you add more power, sure...but that's the case w/ any engine, so you gotta pay to play. It can be argued that adding an intake, exhaust and software (it should be done as a package) could theoretically lower reliability since I guarantee you will be driving the car harder. It's a moot point though because those who modify should also expect a certain detriment of change in longevity, otherwise they'd stay stock because they simply don't care to modify in the first place.

Do I believe that a turbo'ed I6 running a mild 6-8psi will last 6 months or more...abso-friggin-lutely!! Are there cases of where $$Dinan$$ first got into the FI game w/ the M62 V8 and had MAJOR blow-by issues before they switched to the Vortech V2 or V2SQ...abso-friggin-lutely. Did people still pay for $12,000 to $15,000 for their systems...abso-friggin-lutely. Does spending the most money for mods GUARANTEE the best quality...abso-lutely-friggin not!!! Ask any pre Vortech SC owner, or the handful of people who had their motors build for obscene amounts of money by the guys at D/A Motorsports to twin supercharge their 540/M5 engines, only to have catastrophic failures. Hell, look at resale of BMW's in general vs brand neww...ask anyone who bought an X5 brand new if they got their money's worth on their 60k SAV and are spending thousands of dollars to this day on repairing the issues we speak or regularily. Spending large sums of money guarantees nothing except that the seller will definately have a thicker wallet.

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