[Pete E]

Hi all, I would really appreciate some guidance and clarity on this subject because I am really confused about the Dinan Software upgrades and installing Dinan Phase 1 moving to Phase 2 after installing VRSF 3″ Catless Downpipes in my 2008 335i.

I have a 2008 335i Convertible. It already has the Dinan stage 1 software upgrade which is great. I am looking for a more robust sound from my exhaust and maybe a bit of extra HP. I was recommended to install VRSF 3″ Catless Downpipes with ports for the original oxygen sensors.

I want to add the Dinan Stage 2 software upgrade after the VRSF downpipe install to further boost horsepower. Sounds simple and logical right?

This is where the confusion begins. I was told by the BMW performance shop (Strictly BMW in Bellevue WA) that installed my Dinan Stage 1 software, that I cannot install the Dinan Stage 2 software because it will not recognize the aftermarket VRSF downpipes and the car will actually lose horsepower and act 'funny' because it will think some thing is wrong.

They recommended Evolve software with tuner etc. (which they do not provide) However, I don't know if I am buying their advice as they are limited to Dinan and do not install downpipes or performance exhaust systems.

I want to do this right the first time and not screw up my car or the Dinan stage 1 software I paid $450 to have installed.

Bottom line, what I really want some robust tone from my exhaust with out sounding like a teenager. Extra HP is great too.

Your feedback and advice would be greatly appreciated.

Thank you so much in advance for your help everyone!

[Sgop335]

Who is installing the dinan stage 2 and what are the harware requirements?
How much does it cost or is it free?

[LMB335IS]

You've backed yourself into a corner using Dinan. They only use and support 50 state EPA compliant software and hardware. Catless downpipes aren't supported and the software isn't designed to be used with them. Your best option would have been using something like MHD which can be customized for whatever combo of performance parts you want to run and gives you control over the process rather than relying on overpriced dealers to control the process.

[lowrydr310]

Have you tried the golf tee mod? If not, try and see if that gives the exhaust sound you're looking for. I have a 2007 335i and did the "golf tee" modification (actually used the pin from my tensioner instead of a golf tee, spliced inline before the exhaust actuator.)

I'm old and I don't like obnoxious exhaust sounds, and the stock 335i with the golf tee is about as much as I can handle.

You won't pass emissions with catless downpipes, and as everyone says the Dinan tunes don't support them anyway, you're going to have a persistent Service Engine light because of the catalyst monitor failing.