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MRM Performance

MRM Performance B58 Full 4.5" Catless Downpipe

MRM Performance B58 Full 4.5" Catless Downpipe

Regular price $259.99 USD
Regular price $319.99 USD Sale price $259.99 USD
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**OUT OF STOCK, ETA MARCH 2024**
We have our MRM Performance 5" Catless Downpipes in Stock and Ready to Ship!

New Price, now only $259.99!


MRM Performance Full 4.5" Catless Downpipe 

Let your turbo breathe, unlike most other brands that immediately reduce size halfway through the downpipe, our downpipe diameter stays 4.5" for the full length of the downpipe, reducing in size at the very end where it meets the OEM exhaust.

Features:

  • Full 4.5" Downpipe
  • Faster Turbo Spool
  • Deeper & More Aggressive Exhaust Note
  • Gains of 30-50whp with tune
  • Fits RHD and LHD models with no modification necessary
  • 304 Stainless Steel
  • Free MRM Performance Decal Included


Fitment:

Our 4.5" Catless Downpipe fits ALL B58 Models! 

BMW:

  • F-Series B58 M140i M240i 340i 440i 740i
  • G-Series B58 B58TU (Gen1 & 2) M140i M240i M340i M440i 540i 740i X3 M40i X4 M40i X5 40i X6 40i X7 40i

Toyota:

  • A90 A91 Toyota Supra
DOES NOT FIT B58 MODELS WITH OPF SYSTEM (ONLY APPLIES TO CERTAIN EUROPEAN/ASIA MODELS)

Installation Tips:

  • Make sure your V-band bolt is not near the turbo wastegate, as this can can result the wastegate arm hitting the bolt resulting in boost control issues. This is the most common cause of boost issues that people encounter after improperly installing their downpipe.

  • When installing the downpipe, ensure that it is not contacting the frame, trans, or any other point of contact. If it is clock the downpipe to a position where it does not contact. If your downpipe is rattling after install, this is likely going to be the culprit.

Modifying Downpipe For Larger Custom Midpipes:

For those of you looking to go with a larger diameter mid-pipe and to maximize exhaust flow, you can cut the end off of the downpipe and weld on whatever size pipe you need; completely eliminating the bottleneck for a full 4.5" downpipe. Great for fitting those 3.25" - 4.0" midpipes.

*This is not necessary, it's just an option for those with custom exhaust setups that want to get the least restrictive exhaust setup possible*

MRM Performance Downpipe - Maximum Endpipe Diameter


***WALL DECORATION ONLY, THESE ARE NOT INTENDED TO BE USED ON PUBLIC ROADS OR HIGHWAYS, MRM PERFORMANCE IS NOT LIABLE FOR ANY UNINTENDED USE OF THIS PRODUCT***

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Customer Reviews

Based on 17 reviews
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D
Dylan Damian
4.5 catless downpipe B58

The customer service was outstanding. Very prompt responses and had the downpipe delivered within 3 days. Car sounds great and really introduces more turbo / intake noises.

K
K1Auto
MRM B58 4.5inch Downpipe

Man, their product fit like a glove! Very nice quality. We installed it on my Supra the other day and no issues!

D
Daniel Mallette
4.5in B58 Catless Downpipe 21 M340i

Truly unlocks the sound of the B58! The installation took a total of 40 minutes and fit like a glove. I couldn’t be happier with the results and will definitely do lots more business with MRM.The customer support they offer is second to none! They make you feel safe and secure about ordering and are ready answer any questions you have. I can’t recommend this company and product enough. Thank you MRM for your top tier service.