ottac

Hi everyone. New to the 5 Series forums, love what I see so far.

Bought my 2007 550i (sport package) certified pre-owned last year. Love the way it drives already, can't wait to put it on steroids.

Started driving a few autocross events last year, taking it up a notch to the track this year.

Would really love to upgrade before hitting the track, looking for mods with the highest impact/$ on power and performance, without sacrificing ability to add on future mods. Planning to have all the mods done by a good shop in NYC area as I'm dangerous with tools (would welcome suggestions for good shops, nothing like having excellent work done by people who really know what they're doing).

So far I'm thinking a full suspension upgrade (Dinan?) and Michelin racing tires are top priority as I doubt I'm really taking full advantage of the power I already have.

Then I'm thinking a cold air intake and software (Dinan again?)

Also loved the supercharger post...

Really not sure what else I should be focused on at this point, please shower me with your wisdom!

ottac
'07 550i (Sport Package)

'06 550i

Can't go wrong with rpi products, and a trunk lip spoiler(acs) would help put down the power and it looks good everyday.

ottac

Thinking I may need to add a limited slip differential as well...

545IblupasdU

do not use cold air intake (hot air intake)......better to use RPI ram air kit!

'06 550i

LSD is sorta expensive but I guess money isn't an issue in your case

west

My advice to you would be to first make the car as efficient as you can without touching the engine. Lightweight wheels and an LSD are a great start. Keep us posted. The 550 is a fun car to mod.

Arctic-Rodz

what kind of differential are these equipped with from the factory? "one leggers?"

west

Yeah. They come stock with an open differential.

ottac

Thanks west. How is the supercharger working out for you, btw?

ciphin

I drive a similar model 550. I have a 2008 550 with the Sport Auto transmission and Sport package. I was on a similar quest as you -- improve overall handling and performance of my car. I ended up making the following modifications to my car:

• Dinan Free Flow Exhaust
• Dinan High Flow Intake
• Dinan High Flow Throttle Body
• Dinan Carbon Fiber Front Strut Tower Brace
• Dinan Carbon Fiber Rear Shock Tower Brace
• Dinan Stage 1 Suspension System
• Dinan Stage 2 Software
• HRE Performance P40s - 19" in textured black
• Michelin Pilot Super Sport Tires

The largest noticeable impact to performance was the Dinan Stage 2 software coupled with the Throttle Body and Intake replacement. The accelerator became much more responsive and the joy of driving the car increased exponentially. I elected to use Dinan parts as they did not void my factory warranty and Dinan backed all of their work -- whatever BMW wouldn't cover if there was a failure, Dinan would pick up the difference.

The replacement rims removed about 10 lbs from each corner on the car. And the suspension dropped the car another 1/2 to 3/4 of a inch which stiffening up the ride. The tower braces heavily reduced in corner sway. If you're familiar with Texas, we have "Texas u-turns" at almost every major intersection (http://en.wikipedia....ki/Texas_U-turn) and the car can now take one of those at 80+ mph where previously with the suspension modifications you felt uncomfortable around 40 or 50 mph.

On the track I've topped the car out around 165 mph. The car accelerated to 130 mph from zero in less than 15 seconds. The car becomes much more responsive when you put it in sport mode with the sport auto engaged. I probably shaved 4 seconds off the 0 - 130 -- getting there in approx. 11 or 12 seconds.

I've included a few pictures of my car below. Let me know if you have any specific questions.

Todd