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MRM Performance

MRM Performance B58 5" Catless Downpipe (BMW F/G Series, Toyota Supra)

MRM Performance B58 5" Catless Downpipe (BMW F/G Series, Toyota Supra)

Regular price $329.99 USD
Regular price $379.99 USD Sale price $329.99 USD
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**Out Of Stock, Restock ETA June 20-25th**
10% OFF If You Pre-Order Before June 10th!

MRM Performance is proud to introduce our new B58 5" Catless Downpipe, designed to maximize exhaust flow and minimize backpressure! Unlike most downpipes currently available, we have produced a 5" downpipe, which allows your turbo to breath freely with minimal restriction. An added benefit to the 5" design is a more aggressive, and deeper exhaust note compared to the 4.5" Catless Downpipes.

Features:

  • High Flow 5" Design
  • Faster Turbo Spool
  • Deeper & More Aggressive Exhaust Note Compared To 4.5" Counterparts
  • Gains of 40-60whp with tune
  • Decrease WGDC%
  • 304 Stainless Steel
  • Free MRM Performance Decal Included

Fitment:

Fits all models with B58 (Gen 1) or B58TU (Gen 2)!*

*Does not fit B58 models with OPF emissions system. Mostly found in Europe/Asia.

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 Supra

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.
    *MRM Performance 4.5" Downpipe (V1) shown in picture
  • 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 (Optional):

For those of you looking to go with a larger diameter mid-pipe (3.25"+) to minimize backpressure, you can modify the downpipe by cutting off the end reducer and welding on a larger outlet. This eliminates the bottleneck and decreases WGDC significantly. Setups over 700whp+ will benefit the most from this.

*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
*MRM Performance 4.5" Downpipe (V1) shown in picture

***TRACK USE/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 11 reviews
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O
Oshando (New York, US)
MRM Performance B58 5" Catless Downpipe

Issa beasty downpipe

A
Antonetta Tsakonas (Brooklyn, US)
Excellent

Perfect fit really quality so happy

a
ahmed ahmed (Haltom City, US)
Sounds nice

Great piece of metal! Real opens that throat