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Comp Cams Big Mutha' Thumpr Mustang Cams - 05-10 GT/Bullitt

Our Price $733.95
Market Price $815.50  
You save $81.55 (10%)
2 points

Manufacturer  Comp Cams

27-127030
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  • Product Description
  • Installation Info
  • Mustang Fitment

Ford built a great car in the 2005-2010 S197 Mustang, but with a little help from COMP Cams it can sound and perform like a real "hot rod". The Thumpr Ford 3 Valve Cam Sets for 4.6L/5.4L Modular 3 Valve Engines deliver an aggressive "thumping" exhaust idle and generous power gains in the middle & upper rpm range. These cams will turn your naturally aspirated or blower-equipped Ford 3 valve engine into a performance machine with a minimum of installation difficulty; only requiring the addition of the COMP Cams® Cam Phaser Limiter Kit (#5449) and computer tuning. The COMP Cams® Cam Phaser Limiter Kit (#5449) safely modifies the factory variable cam timing (VCT) system allowing for the use of aggressive camshaft lobe technology without sacrificing the benefits of the VCT. Extensive testing of these new camshaft combinations has confirmed repeatable power gains of 25+ rear wheel horsepower with no sacrifices in long term durability.

427-127010 - THUMPER (PHASERS AND TUNING REQUIRED)

Great idle with excellent power. Good mid-range torque & power gains above 4500 rpm. Compatible with stock valve springs, converter & gears; requires cam phaser upgrade & custom tuning.

427-127020 - MUTHA' THUMPR (PHASERS AND TUNING REQUIRED)

Very rough idle, biggest cam for stock heads. Great power above 4900 rpm. Compatible with stock valve springs, benefits from converter & gears, requires cam phaser upgrade & custom tuning.

427-127030 BIG MUTHA' THUMPR (PHASERS AND TUNING REQUIRED)

Extremely rough idle, needs stroker motor and/or ported heads. Major hp gains to 6800 rpm. Best with 3.73+ gears & 2500 stall. Compatible with stock valve springs, but requires cam phaser upgrade & custom tuning.

427-5449 - PHASER LIMITERS

These limiter plates replace the factory back-plate on the cam phaser. They have posts which extend into the cam gear's control chambers, limiting their movement to no more than 20 degrees. This gives more piston to valve clearance and lets you install bigger, more powerful camshafts with safe piston to valve clearances. While keeping up to 20 degrees of movement available, all the wide-open throttle benefits of the cam phasing are retained, since the normal retard the cams see at wide-open throttle is only around 9 degrees.

Product Benefits

  • Delivers an aggressive “thumping” exhaust idle
  • Generous power gains in the middle & upper rpm range
  • Aggressive camshaft lobe technology without sacrificing the benefits of the VCT
Time to Install
About 10 Hours
Level of Difficulty
Tech Required
Tools Needed
Shop Tools
Model Year(s)
2010 2009 2008 2007 2006 2005

Model(s)
Bullitt GT

Transmission(s)
Manual Automatic

Product Reviews

Wow stop lights will never be the same! The idle of these cams is sick.

My car sounds like a Beast !!