U could use Tomei cams, there interchangeable if u swap RB25-26 so its not a bad investment .
For the specs. taken form rb20det.com
About: As far as i know rb20det stands for RB, race build or breed, 20 is the engine size, D means dual overhead cam, E means electronic fuel injection and T stands for turbo.
The rb20det was the engine that started it all, yep the rb26dett gtr engine was in a way developed from the rb20det, nissan launched the rb20det for the r31 skyline in 1986.
RB20DET specs:
No. and arrangement of cylinders = 6, in-line, vertical
Combustion chamber type = Hemi-spherical
Valve arrangement = Overhead valve type
Camshaft arrangement = Double Overhead Camshaft
Total displacement cc = 1998cc
Bore x Stroke mm = 78.0 x 69.7
Compression = 8.5:1
Bhp = 214bhp at 6600rpm at flywheel
transmission loss = 38bhp
torque = 185 lb/ft
Detail specs =
Vehicle model hcr32 and hnr32
Engine type rb20det
Displacement cc 1998
Combustion chamber pent-roof type
Valve arrangement DOHC belt drive
Bore x stroke mm 78.0 x 69.7
Compression ratio 8.5
Compression pressure (kg / cm2) / (rpm) 12.0 / 300
Maximun output (net) (ps / rpm) 215 / 6400
Maximun torque (net) (kg-m / rpm) 27.0 / 3200
Fuel consumption ratio (g / GS.h) / (rpm) 215 / 2400
Dimensions m/t (l / w / h) (mm) 845x660x685
Dimensions a/t (l / w / h) (mm) 830x660x685
Idle speed (rpm) 800
ignition timing a/t (BTDCdegrees / rpm) 15 / 650
ignition timing m/t (BTDCdegrees / rpm) 20 / 650
Firing order 1-5-3-6-2-4
Valve clearance cold (mm) intake 0.45 +/- 0.003
Valve clearance cold (mm) exhaust 0.38 +/- 0.003
Throttle chamber bolts torque setting (kg-m) first stage 0.9 - 1.1
Throttle chamber bolts torque setting (kg-m) second stage 1.8 - 2.2
Fly wheel run-out limit (mm) 0.10
Con rod nut tightening stage 1 (kg-m) 2.3 - 2.9
Con rod nut tightening stage 2(kg-m) 3.9 - 4.5