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Scat Stroker Series 9000 331 ci Street-Strip Rotating Assembly (79-95 5.0L)

AmericanMuscle no longer carries the Scat Stroker Series 9000 331 ci Street-Strip Rotating Assembly (79-95 5.0L). Please check out Mustang Crate Engines and Blocks for an updated selection.

Features, Video & Details

  • Scat Series 9000 Street-Strip Rotating Assembly
  • Punch Out Your 302ci to a 331ci for More Power
  • Includes Cast Crankshaft, I-Beam Connecting Rods, and Forged Flat Top Pistons
  • 4.030" Bore
  • 3.250" Crank Stroke
  • 5.400" Rod Length
  • Compression Ratio 10.4:1 W/58cc; 9.7:1 W/64cc; 8.9:1 W/70cc
  • Unbalanced Kit - Use 28oz Balancer & 28oz Flywheel/Flexplate
  • Fits 1979 to 1995 5.0L Mustangs

Review & Installation Video

Review & Install Video

Stroker Kit. There is no replacement for displacement, so punch out your 302 V8 to a more respectable 331 for more asphalt-chewing horsepower with a Scat Stroker Series 9000 Street-Strip Rotating Assembly.

Kit Includes. Maximize the displacement of your engine with a cubic inch-enhancing stroker kit that includes a 9000 Series cast crankshaft, Pro Stock I-beam connecting rods with ARP 8740 3/8" cap screw bolts, forged flat top pistons as well as rings and main & rod bearings.

Compression Ratio. The Scat Stroker Kit will allow for different compression ratios depending on the heads installed. Examples: 10.4:1 with 58cc heads; 9.7:1 with 64cc heads; 8.9:1 with 70cc heads.

Unbalanced Kit. This Rotating Assembly comes unbalanced and will need to be professionally balanced before installation. It requires the use of a 28 oz harmonic balancer as well as a matching 28 oz flywheel or flexplate.

Application. This Scat Stroker Series 9000 331ci Street-Strip Rotating Assembly Kit is designed to fit 1979 to 1995 Mustangs equipped with the iconic pushrod 5.0L engine including the 5.0 LX, GT and SVT Cobra models.

Fitment: 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 Details

MPN# 1-94055

CA Residents: WARNING: Cancer and Reproductive Harm -

What's in the Box
  • (1) Crankshaft
  • (8) Connecting Rods
  • (8) Pistons
  • Rings
  • Bearings
Installation Info
Tech Specs
Will it fit my Mustang?

    Customer Photos

      Questions & Answers (12)

      5 Top Rated Questions

      can this be used with stock heads

      • The Scat Stroker Series 9000 331 ci Street-Strip Rotating Assembly can be used with stock heads, however the stock heads would be a major bottleneck, severely limiting the performance potential.

      Helpful (1)

      Hey there. I'm building up an 1988 302 and was wondering a couple of things. The rough bore came out to 20 over. "4.020" and was wondering if i could order the kit through you guys at 20 over instead of 30 over. Also, is the kit capable of being internally balanced? or will I have to go with an external balance.

      • Hello! We only offer the Scat Stroker Series 9000 331 ci Street-Strip Rotating Assembly with a bore of 4.030. It will require the use of a 28oz Harmonic Balancer.

      Helpful (1)

      How much lift and duration can I go with these pistons?

      • The amount of lift and duration you can safely achieve with these pistons will depend on several factors, including the deck height of your engine, as there is variance in this, sometimes even side to side on some engines, thickness of the head gaskets, and the specific heads and valve size.

      Helpful (0)

      With this kit. I use a 28oz flywheel and balancer. Does that mean it does not have to go to a machine shop to get balanced.

      • It is required to have this kit professionally balanced before installation, and will also require the use of a 28oz balancer and flywheel.

      Helpful (0)

      Valve relief on pistons, I am planning on using trick flow 11R twisted wedge heads will these pistons clear if not will I be able to purchase this kit with a set with proper valve relief

      • The Scat Stroker Series 9000 331 ci Street-Strip Rotating Assembly will use inline valve reliefs.

      Helpful (0)
      Post Your Question
      7 More Questions
      Does it have to be balance or can u put 28oz Hermonicbalancer 1 answer
      are the connecting rods forged 4340 ? 1 answer
      Whats the hp rating on this stroket kit 1 answer
      will this kit fit my 1966 Ford Mustang? (289 ci block). I noticed in the description its listed that it fits a 302 ci block. Just wanted to be sure before I purchased it. 1 answer
      Can you please provide details of piston; maker, CC, Compression Height, etc. Thans 1 answer
      Will this clear the oil pan Will this clear the factory oil pan on 89 5.0 ho 2 answers
      What do i need in terms of a balancer/flywheel I understand that this kit is set up for 28oz balance. I am assuming i need a 28oz balancer but what do i do for a flywheel? 1 answer

        Customer Reviews (1) Write a Review

        Overall Rating 5

        out of 5 stars

        • Performance Gain 5 5
        • Fit 5 5

        • 5/5

          February 22, 2017


          Not installed yet but I'm a huge fan of the quality of this product. Can't wait to install


          Year: 1995 Submodel: GT

          Helpful (12)

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