REDS Racing R5S US Special Edition .21 5-Port Off-Road Competition Engine w/HCX (Turbo Plug)


SKU: REDR5S Category:


This is the REDS Engines R5S US Special Edition .21 5-Port Off-Road Competition Buggy Engine. Based on R5R, the R5S takes the tuning from the R5 Team Edition 3.0 to deliver a best of both worlds engine with a smooth, usable power band. This engine is only available to North American customers.

Why should you buy an R5S?
The R5S provides budget concious drivers a reasonably priced option that delivers the performance and quality you would expect from higher priced engines. They are each individually tuned and subjected to strict quality control measures that guarantee repeatable performance and greater reliability.

HCX Horizontal Carburetor – Higher Idle Stability
The revolutionary carburetor features a horizontally positioned top end needle that provides a more stable idle, more precise tuning, and higher mid/top end power.

Handmade, Tuned and Assembled – Mario Rossi
All parts are matched and measured by Mario Rossi within certain tolerances, then hand built by him personally. The engine leaves the factory with a hand inspection of all components and compression is checked.


  • Ultra-light at just 348 grams
  • 5 Port hard chromed liner
  • CNC machined billet piston
  • Redesigned separated and cooled combustion chamber
  • Lightweight cooling head
  • 14mm crankshaft
  • Knife edged aerodynamic connecting rod
  • Swiss Made steel rear bearing
  • Japan Made steel front bearing
  • HCX carburetor

Category: 1/8 off road
Displacement: 3.5cc
Bore: 16.26mm
Stroke: 16.80mm
Front Ball Bearing: 7x19x6 Japan made
Rear Ball Bearing: 15×25.4×6 Swiss made
Carburetor: HCX 7mm
Weight: 348g
Recommended Pipe: EFRA 2104, 2112 w/S or XS manifold
Recommended Fuel: 20-30% nitro, 8-10% oil
Break-in Fuel: 12% oil