Which would you do? (and why?) - The Unofficial BMW M5 Messageboard (m5board.com)

ashbash · 9th June 2006, 09:15

So I've been thinking about spending a little money on car related items and am considering one or more or less of the following...

As background you should know that my beast is an 02 with 52k miles on it (4k by me in the last 6 months) and is my daily driver. This mileage will be fairly typical. I am generally in traffic for about 30 minutes/14 miles in each direction each day, but can occasionally luck out and get no traffic on the am ride (and walked/ran away at 110 from a Pontiac GTO this morning). I have CPO/Extended Maintainence/Warranty, so most of the big stuff is covered - and I am breaking in a new clutch as we speak (120 miles down, ? to go). I will never track the car. I rarely am above 100 for any extended period of time - I just don't travel very long distances, and am only comfortable at those speeds when other people aren't around (and I don't have my kids in the car).

So, with those in mind, which of these would you do, if any. And if more than one, which order. And why? I am looking to spend $5k or less installed.

1. New suspension - I get a fairly substantial squish from front and rear over speed humps, and have noticed a moderate amount of front-end dive under heavy braking, so it might be time for a replacement. That said, it is still stiffer than any other car I've owned, and my friend's <1y old Mustang GT. In consideration are PSS9s, Ground Controls, and Dinan Stage II - which one given that I will never track this car and the only back-sear passengers are my kids in car seats and that is maybe 3x/month (we use the wife's SUV mainly).

2. 3.45 Rear Diff - Dinan or Evosport.
3. Headers - Supersprint (Dinan not in my $ range)
- #2 and 3 go together. I have read the many threads on how headers are the biggest bang for buck hp/$ mod - but for a 400hp car that is a daily driver and is rarely above 100 for extended periods of time and never tracked - are headers a better purchase than the perceived gains of the diff? Also, total cost with labor makes these largely different.

4. Something else entirely (vacation, new watch, etc.).

Thoughts?

-Ash

jclyman · 9th June 2006, 11:57

I love my M5 ... am driving to Texas (3,000 miles RT) for one day at the end of the month ...

But, I would choose a vacation.

Blue Thunder · 9th June 2006, 12:23

I´d put your options in the following order:

Suspension
Headers
Diff

Dunno where to put vacation - you didn´t mention anything about needing one

The reason I´d put suspension before headers is that if you are not 100% confident/comfortable with your suspension it makes no sense to add power.

And regarding the diff I have yet to see any empirical data that is makes an M5 any faster.

mr_bock · 9th June 2006, 13:34

I think it depends on how much pleasure you get from driving your M5. A vacation is short, but could have great memories. If you start putting mods to the car, it could start you on the slippery slope of more and more mods....

As Blue Thunder says... do the suspension first.

If you do headers, you should consider cat back exhaust too, and there went the budget.

Good Luck and enjoy that Beast!!!!!!!!!!!!

gsfent · 9th June 2006, 16:48

Quote:

Originally Posted by Blue Thunder

I´d put your options in the following order:

Suspension
Headers
Diff

Dunno where to put vacation - you didn´t mention anything about needing one

The reason I´d put suspension before headers is that if you are not 100% confident/comfortable with your suspension it makes no sense to add power.

And regarding the diff I have yet to see any empirical data that is makes an M5 any faster.

I would agree.

For the original poster, suspension choices are similar in price, but I think Dinan has a great compromise for ride and handling, yet can see occassional track duty. Since track is not an option, you don't need the coilover adjustability. But try to ride in cars with the different suspensions if possible, since it is very subjective. If you do Dinan, the differnce between II and III are the camber plates. I like 'em, but your call.

Headers really free up the car. You will see about 30 rwhp. Feels like a different car. Expect to spend over $3500-$3800 installed (SS headers) and you will need an ECU upgrade, between about $600-$900. Most people like Powerchip, Dinan is also an option, as is Active Autoworks.

I don't know if the diff really helps; those that have bought it seem to like it. I think the car has more than enough rear gear, given tranny ratios and torque. JUst IMHO. The car will FEEL faster, no doubt. Given a choice between diff and more expensive headers, I would go with the headers.

A couple of other items. Stock shifter is pretty mushy, many people add a short shift kit (SSK) and really improves the driveability in everyday use. Rogue and UUC are two top names that come to mind, there are others. Do a search and read up. Also consider better tranny mounts while you are doing the SSK.

Rear swaybar is a known weak link. There is a thread about some better brackets going right now. And member TCM may still sell some. Beastpower has them on his website, good deal when he puts them on sale, a little pricey otherwise. But they do solve the problem of broken sway bar brackets.

Have fun!!
Regards,
Jerry

suprfknman · 9th June 2006, 18:40

PSS9 suspension but you have to have it installed by a competent shop, drop it down around an inch in the front and then have them set the back 1 notch higher. This worked great for me. Have the dealer put new fluid in the trans and rear diff its around 4-500 bucks but it smooths out shifts and driving alot.