RB26DETT information : The myths , the truths

Twin T51R SPL RB26DETT

The RB26DETT. An engine of much myth. We are going to try and set out some truths.

• Rated at 280 hp stock from 1989-2002
  
• Found in the R32, R33, R34 GT-R
  
• Inline 6
• Iron block, aluminum head
• 2568cc of displacement
• 86mm bore x 73.7mm stroke
• Twin turbo
• Individual throttle bodies - thats six
• Coil on plug ignition
• Interference engine



Stock R32 Dyno chart

Top of the motor

• Valve/Cam covers
• Aluminum.Black on R32/R33. Red on R34. Nur on the Nurs. Two
  breathers located at the back of the plenum. Drivers side goes to PCV
  valve. There is a crossover tube. Left side goes to the inlet
  side of the rear turbo. 

• Spark plug cover
• We like to leave them off to keep the coils cooler. The engine looks
  more finished with the spark plug cover. You know the piece. Says
  RB26DETT on it.
• Front cover
• The piece that says RB26. Covers the timing belt. Not recommended to leave off. Aluminum on R32/R33. Plastic on R34.
• Igniter box
• R32/R33 located at the back of the spark plug cover. Igniters are build into the coils in the R34.
• Coils
• Coil on plug. R32/R33 are the same. R34s have the igniter built in. 
•  

  

  RB26 coils
• Spark Plugs

• PFR6A-11 are the stock plugs.

• Camshafts
• Intake 8.58 240 duration 113 deg Lobe Center -R34N1 117 deg Lobe Center
  
• Exhaust 8.28 236 duration 125 deg Lobe Center-R33N1 120 deg Lobe Center - R34N1 121 deg
  
• Valves
• Intake 34.5 mm
• Exhaust 30 mm
• Head bolts
• (14) 12 mm head bolts
• Head
• 4 valves per cylinder. Twin cam. Cam on bucket. Shim under bucket adjustment
• Head gasket

RB26 combustion chamber

Induction side

• Plenum - Collector
  

• Lean cylinder is #6.

• Throttle body
• 6 individual throttle bodies. Cars have done over 1000 whp on stock throttle bodies.
• XS replacement throttle seals
• Balance tube
• Vacuum/boost and water pass though the balance tube

Exhaust side

• Exhaust manifold

• Stock
  
• N1



Stock manifold on left, Modified N1 on the right
• Turbocharger
• Ceramic exhaust wheels that break off
  
• Exhaust elbow/Outlet pipe
  
• Downpipe(Frontpipe)

Bottom end of the motor

• Pistons

• 86mm. Stock pistons are oil cooled. 1.5 mm top ring, 1.5 mm 2nd ring. 
• N1 has 1.2 mm top and 2nd ring
• Rods
• 121.5mm center to center. 
• RB28's have 119.5 c-c except in a GT block
• Oil squirters
  
• Crankshaft
• Early narrow oil pump drive
• Late wide oil pump drive
  
• Main cap/girdle
• 7 main bearings. #4 being the center main bearing and
  containing the thrust bearing. The other 6 bearings are the same
  construction.
• 
• Oil pan

• Cast aluminum. Contains the front differential.

• Block

• 05u on the side. Thats a standard block.
  
• 24U on the side. Thats an N1 block
  
• RRR on the side .GT Block . That one is special
• Water pump
• Stock
  
• N1 
•  

  

  Far pump is N1, close is normal. Notice the N1 backing plate

  
  

Engine Control Unit

• ECU
  

• MAF
• 65mm. Each will meter air up to about 200 whp each.
• Fuel injectors
• 444 cc. Yellow top. Top feed, Low impedance
  
• Fuel pump
• 195 liters per hour - R32
  
• Crank angle sensor
• R32-R33
  
• R34
  
• The R34 uses a different cam drive for the sensor.
• Checking ignition timing and TDC

Induction

• Inlet piping

• Rear inlet piping collapses under boost.Replacing it with hardpipe is recommended.
• Turbo outlet piping
• The stock outlet piping causes the air out of the turbocharges to come together roughly.
• Testing a modified "twin turbo" pipe
  
• Intercooler
• Stock intercooler will provide better response to approximately 600 wheel horsepower.

Buy RB26 , RB26DETT parts here. Gasket kits , water pumps , timing belts , camshafts. New OEM, and aftermarket parts. .