[s2kvee]

I have a 2013 production at March. According to info online I have the 3.5" downpipe, and the 4" versions won't work.

Here's my issue, I picked up a new downpipe locally, brand is Topspeed Pro1, got it super cheap, pretty much almost free since it was combined with other stuff.

Description states this is a 4" model and wouldn't work for my Pre 07/2013.

However I found a listing where one customer was able to install it on his 2012.

Can anyone please take a measurement picture of their downpipe / catylatic converter vband flange. I'm looking for info specific for 2012 models and 2014+ models for comparison

Looking :
Inlet flange (inner diameter & outer diameter)
Outlet flange (inlet diameter & outlet diameter)

For both 2012 models as well as 2014+ models

Any info is greatly appreciated. Thanks

[s2kvee]

When they list downpipes at either 3.5" or 4" I'm not sure if they ment inner diameter or outer. I'm looking to compare these measurements to determine if I can use that DP on my car.

[1QuikWS6]

Its outer diameter

I posted the 2014 4" flange dims in your other thread for turbo end:

4"OD - 3-5/8" ID

[s2kvee]

Which is weird. I have spoke to another member here with a 2/2013 model and have the VrSF downpipe. His measurements also showed 4" OD for inlet and 3.5" for OD outlet..
The Topspeed downpipe I have which supposely is for 2014 models are also the same measurements. But an ebay seller claims to have had it installed on his 2012 models as well.

[1QuikWS6]

Idk how he could have installed a 4" OD DP on a 2012??

The dims I posted in your other thread & sizes are directly from FabSpeed - pretty sure they know what they are talking about as they are in the business of making DP's

According to them F30/F32 335/435 pre 08-2013 with a Mechanical Wastegate uses the 3.5" OD Inlet DP & anything post 08/2013 with an Electronic Wastegate uses the 4"OD Inlet DP

The inlet dims (turbo side flange) of 4" OD - 3-5/8" ID were taken directly off my Fabspeed HJS Catted DP (sorry didn't measure the outlet (exhaust side of the pipe before installing)

Only thing I can think of is the person that stated they had it on their 2012 was either incorrect, or had their turbo swapped out for aftermarket turbo.

I can't believe they would have gone to the trouble of swapping a later OEM version elec wastegate turbo into a mech wastegate car as there would have to be retrofitting to allow DME to control different type of wastegate

The Fabspeed DP I measured is installed on my 2014 435 N55 with build date of 09-2014

[s2kvee]

I'm not doubting you on this info. I trying to clear up the confusion. Comparing the VRSF downpipes difference. The one that the guy posted looks like the 2012-2013 Models with the flex pipe. And it did measure at 4"

[s2kvee]

Alrite, i went ahead and swapped my downpipe today for a catless, one, my car has a production date of 1/2013 so that should be with the 3.5" flange. I have the PWG since i installed the blue wires on the JB4 today as well. Anyways. I took off the stock catylatic downpipe and measured it. And for some reason, it is indeed a 4" OD flange. Im not sure why it is but the measurements all matches up. Its a 4" OD Inlet (Turbo) and a 3.5" outlets (Exhaust). The downpipe installed was the Topspeed Pro1 which they market for the 8/2013-2015 models. However it fits my 1/2013 model. This is also confirmed by another ebay seller who claims to have the same downpipe installed on his 2012 model.

Another member here is selling his VRSF downpipe, the same downpipe pictured on the VRSF website (with flex pipe) for 2012-2013 model. His f30 has a production date of 2/2013 but it also measured at 4" inlet and 3.5 outlet...


what the hell is going on here? , im not complaining, My install went pretty well but somehow, something changed...


does anyone have a 2014 downpipe they can measure?

[cngo]

Post pics of all the measurements

[s2kvee]

pics of the VRSF 2012- 7/2013 Test pipe

[s2kvee]

Top speed pro1 downpipe next to my 2013 Stock catalytic converter

[cngo]

I might be mistaken but the measurements aren't supposed to be taken of the entire diameter of the flange. If the measurement is taken from the actual opening of the inlet of a pre-07/2013 downpipe, it should be a little less than 3.5".

[s2kvee]

Yes that's. Correct, the inner diameter is smaller.. slightly under 3.5" however that's where most people are saying how to differentiate the downpipes. The 3.5" vs 4" flange.

It would help a lot if someone has a 2014 stock downpipe that they can measure for comparasion

[JaredG_F30]

Here are my dims off the stock DP from a 2014 F30 335i. Build date is 8/2013 and it's EWG. I replaced this with the VRSF 4" DP for F30 N55.

[s2kvee]

Originally Posted by JaredG_F30

Here are my dims off the stock DP from a 2014 F30 335i. Build date is 8/2013 and it's EWG. I replaced this with the VRSF 4" DP for F30 N55.

awesome... that makes more sense now... in reality.. the 2013 actually has 4" flange where as the 2014 models have the 4.5" flange... not the 3.5/4 difference... it seems like the outlet is the same... but the inlet is where its different.