S60 2.5T downpipe vs. R downpipe (are they the same?)

Post by **justanotherhumanoid** » 30 Dec 2020, 11:21

So I have a 2006 2.5T AWD with stock downpipe, and I also have in my possession an "R" (at least from what I was told) downpipe that I was planning to swap in... when I was in the vicinity of the downpipe recently, I noticed that I could not discern a difference in diameter visually, so I broke out the digital calipers and measured them both at the turbo end and the catalytic converter end. They appear to measure the same diameter at both ends.

Is there some other difference I'm missing? Am I just bad at measuring? Is this "R" downpipe actually something else? Granted it was a little difficult to work the calipers onto the one that's installed, but I'm pretty confident that these measurements are accurate for both the downpipes I have. Here's what I measured on both:

So... should I just leave the 2.5T downpipe in there, since it appears to be the same as the "R" downpipe... or is what I think is an "R" downpipe actually a 2.5T or something else, i.e. have I been had?

I guess what I'm really asking is, can anyone confirm these measurements on a certified real-deal "R" downpipe?

Post by **- Pete -** » 30 Dec 2020, 17:20

I also am unable to see any discernible difference between my R & 2.5T downpipes. I’m willing to bet they are the same. Fit-wise, ordering an aftermarket “high flow” DP (catted or catless) is the same 2.5T vs R.

That being said. It’s pretty safe to say there would be no gain from installing a stock R DP.

Edit: I should say that all my original/stock DP’s are removed from my P2’s & have been replaced with catted higher flowing DP’s. Side by side, there is no difference between the 2.5T & R DP.

Post by **erikv11** » 30 Dec 2020, 19:04

I would be surprised if there was any difference. I can measure the front dimension on my 06 R for you if it can be done from the top - too cold to get under the car right now!

Post by **justanotherhumanoid** » 31 Dec 2020, 11:40

Based on Pete's corroboration, I'd say save yourself the trouble - I'm calling them the same and I won't bother swapping them, unless someone chimes in with some other data. Glad I didn't go to the trouble of swapping them, and saved some work/effort (until turbo-swap time, at which point it's probably coming out anyway...). Thanks all.

Post by **xHeart** » 31 Dec 2020, 12:05

There are 2 part numbers for the 2.5T, 30793720 & 30793721.

See this for WHAT IT FITS https://parts.volvocarslisle.com/p/Volv ... 93721.html

Post by **- Pete -** » 31 Dec 2020, 15:33

For what it’s worth, the Mototec downpipe is very nice & has a removable catalytic converter (3-piece DP, nice V-band connections). Snabb & Revolve also make a nice low-cost 1-piece DP. I have found on both R & 2.5T (healthy) engines that with any of these DP’s you will need to run a downstream defouler/O2 spoofer. Maybe not at first, but eventually you will need to install one.