Dinan stage 1 on 50i = Big Win

[TahoeM3]

So I got the Dinan stage 1 installed today (stage 2 not available).

Impressions from routine driving home and some more spirited driving to test it out:

Throttle response - greatly improved. It no longer feels like there is a stone flywheel that you have to get moving. Light/partial throttle moves off the line smoothly (as opposed to laggy as before), full throttle pulls HARD off the line. Brake torquing to 2000rpm launch pins you back into the seat. Not as hard as an X5M launch but a LOT better than the stock 50i.

Higher-end power - also greatly improved. Not quite as quick as the 550i or X5M (which are pretty much equal) on the highway but noticeably improved.

Other areas of improvement:

Shifting speed - Improved in all modes.

Shift logic - Improved in all modes. Hold gears longer in lower gears with part throttle application.

Steering weight? - This is one that surprised me, but the steering (which in stock form felt heavier than previous X5s I have had), is now noticeably lighter at lower speeds. I wasn't expecting this and wondered if I was imagining it, so I tried some testing to reproduce it and it seems to be real. I'll follow up on this.

Overall a big win for me as it made the 50i a lot closer to the M without compromising highway gas mileage. I can't say how it compares to the other tuners, which are probably very similar, but I'm very pleased. It was pricey, but it was done at the dealership and the warranty gives me peace of mind.

[nyranger74]

The stage 2 is available, its not on the website. Your dealer could call Dinan to confirm

[bairen]

Originally Posted by nyranger74

The stage 2 is available, its not on the website. Your dealer could call Dinan to confirm

$3000? wow... does dinan ever offer a sale on these mods?

[TahoeM3]

Originally Posted by nyranger74

The stage 2 is available, its not on the website. Your dealer could call Dinan to confirm

I thought so, too. My dealer said no, but I thought you had the stage 2. I was going to push it, but I decided to wait until they come out with an intake (which will require a retune) and upgrade again then.

So far, very very happy with the stage 1. Once I improve the breathing a bit it will be even better.

[Maxx2]

Originally Posted by TahoeM3

So I got the Dinan stage 1 installed today (stage 2 not available).

Impressions from routine driving home and some more spirited driving to test it out:

Throttle response - greatly improved. It no longer feels like there is a stone flywheel that you have to get moving. Light/partial throttle moves off the line smoothly (as opposed to laggy as before), full throttle pulls HARD off the line. Brake torquing to 2000rpm launch pins you back into the seat. Not as hard as an X5M launch but a LOT better than the stock 50i.

Higher-end power - also greatly improved. Not quite as quick as the 550i or X5M (which are pretty much equal) on the highway but noticeably improved.

Other areas of improvement:

Shifting speed - Improved in all modes.

Shift logic - Improved in all modes. Hold gears longer in lower gears with part throttle application.

Steering weight? - This is one that surprised me, but the steering (which in stock form felt heavier than previous X5s I have had), is now noticeably lighter at lower speeds. I wasn't expecting this and wondered if I was imagining it, so I tried some testing to reproduce it and it seems to be real. I'll follow up on this.

Overall a big win for me as it made the 50i a lot closer to the M without compromising highway gas mileage. I can't say how it compares to the other tuners, which are probably very similar, but I'm very pleased. It was pricey, but it was done at the dealership and the warranty gives me peace of mind.

Haven't been around recently, but great to hear your impressions given the fact that you have first hand experience with the X5M as a daily driver.

It's odd that Dinan responded to my email stating that the stage 2 and stage 3 tunes are available and yet they do not update their website.

Hopefully, they develop something on the intake side and we can see even bigger gains...

Btw, do you have any plans of putting it on a dyno?

[Droptopp]

Have you had the opportunity to take it to a 1/4 mile track?

Stage II is impressive as well.

[TahoeM3]

These guys got 395 hp and 480 ft-lbs at the wheels on the dyno.

A couple of things on the 50i that are better than on the M. On the M, in manual mode the transmission won't shift at redline. The problem is that the tach spins so fast, it's tough to shift in time and you hit the rev limiter especially in 1st. Even if you shift at 6000 rpm it's too late, as the rev limiter is at an indicated 6500 in 1st. You have to hit the shift paddle by 5500 or you will hit the limiter. The only way around this is using launch control, but you can't do that all the time. On the opposite side, S-mode is not aggressive enough and will shift to 2nd quickly unless you punch it off the line.

Both shift down aggressively in S-mode rolling up to a stop, but with the 8-speed on the 50i, the shifts aren't as jerky or annoying. On the M, it is not smooth at all.

[GmoneyLI]

Originally Posted by TahoeM3

These guys got 395 hp and 480 ft-lbs at the wheels on the dyno.

A couple of things on the 50i that are better than on the M. On the M, in manual mode the transmission won't shift at redline. The problem is that the tach spins so fast, it's tough to shift in time and you hit the rev limiter especially in 1st. Even if you shift at 6000 rpm it's too late, as the rev limiter is at an indicated 6500 in 1st. You have to hit the shift paddle by 5500 or you will hit the limiter. The only way around this is using launch control, but you can't do that all the time. On the opposite side, S-mode is not aggressive enough and will shift to 2nd quickly unless you punch it off the line.

Both shift down aggressively in S-mode rolling up to a stop, but with the 8-speed on the 50i, the shifts aren't as jerky or annoying. On the M, it is not smooth at all.

I haven't had any issues shifting before the rev limiter in manual mode with my M. Now in the B7 I had.. While different story. Shortest 1st gear I've ever seen. In auto the car starts in 2nd. U have to manually put it in 1st.

[TahoeM3]

Originally Posted by GmoneyLI

I haven't had any issues shifting before the rev limiter in manual mode with my M. Now in the B7 I had.. While different story. Shortest 1st gear I've ever seen. In auto the car starts in 2nd. U have to manually put it in 1st.

In D it starts in 2nd. In DS it starts in first. That's the same across all models.

[Droptopp]

With Stage I when decelerating to a stop does the 2 to 1 downshift slow you to an almost stop well short of your actual intended stop?

Mine is getting better in non sport mode but from time to time 30% of the time the 2 to 1 would almost stop me 60 ft before intended stop and I will actually have to accelerate to the stop sign/light, etc.

Yours do this?

[TahoeM3]

Originally Posted by Spdgtkt

With Stage I when decelerating to a stop does the 2 to 1 downshift slow you to an almost stop well short of your actual intended stop?

Mine is getting better in non sport mode but from time to time 30% of the time the 2 to 1 would almost stop me 60 ft before intended stop and I will actually have to accelerate to the stop sign/light, etc.

Yours do this?

It's not as bad as in the M. It used to drive me crazy slowing to a stop the way it would lurch on downshift. It was almost impossible to stop smoothly.

[kk15]

I experience the same on downshift, but what I find annoying is the abruptness of the 1-2 upshift (when driving in D). As a daily city driver this makes for a very unpleasant driving experience.

I realize this thread has been more on the performance side, but does everyone experience this (an abrupt 1-2 upshift)?

Note - I know it was mentioned that it starts in 2nd when in D but this doesn't seem to be the case (maybe that's the problem I'm experiencing)