AIRTEC 2.5 inch Big Boost Pipes with 70mm Cold Side for Mk2 Focus ST and RS

AIRTEC now brings you the 2.5″ big boost pipe kit with the larger 70mm cold side hose

Please note: For Focus ST 225 – MUST Be fitted with 2.5″ outlets on intercooler. Stock ST has 2″ outlets and will also NOT fit Focus ST Stage 1/2 intercooler but WILL fit our Focus ST Stage 3 intercooler.

AIRTEC part no: ATMSFO55

From £382.02 (inc VAT)
£318.35 (exc VAT)

Technical Data

The 2.5″ big boost pipe kit is a must for all remapped RS and ST’s, Everything you need is included in the kit.


  • Hot side (turbo to intercooler) is made from 2.5″ light-weight alloy and connected with 5 ply silicone hose joiners.
  • NEW! Now comes with 70mm coldside hose to fit standard size throttle body expanding up to 70mm
    Please Note: This is a Symposer Delete Item

Will fit With the following intercoolers:

  • Pace
  • Pro-Alloy
  • Forge
  • Ford OEM

Direct replacement! No modding required.

Our 2.5″ hard pipe upgrade removes Ford’s 2.0″ restrictive boost pipes. We saw gains of 11.8 bhp & 9 lb/ft torque increases over standard and these gains were achieved by simply bolting on the kit.
This kit is designed for BIG BHP Focus RS and will work best on cars with 375bhp and over.

All pipes have swaged ends to stop hoses from popping off when running higher boost levels

Choose from options throttle body size:
Standard Throttle Body  (63mm)
Uprated Throttle Body (70mm)

Fitting takes 1 – 2 hours.

Please note: For Focus ST 225 – MUST Be fitted with 2.5″ outlets on intercooler. Stock ST is 2″.
Will NOT fit Focus ST Stage 1/2 intercooler. WILL fit focus ST Stage 3 intercooler.

Please Note: Pipework only available in black.

Please note: Custom colours are made to order, please expect a 5-10 day delay on custom colours.
Peak show times may be a longer 7-10 day delay.

AIRTEC part no: ATMSFO55

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