Infiniti Q45 Vs. Lexus LS400







DOHC 32-Valve V8 with aluminum-alloy block and heads with molybdenum coated pistons DOHC 32-Valve V8 with aluminum-alloy block and heads.


4.5 Liters 4.0 Liters


278 @ 6000rpm 250 @ 5600rpm (SC400)


292 @ 4000rpm. 260 @ 4400rpm (SC400)
Bore x Stroke


93 x 82.7mm 87.5 x 82.5mm
Main Bearing and Support


6 bolt main bearings (bigger) with cradle support. 4 studs, 2 bolt mains. (Total Six stud/bolt main)


90 degree forged steel. Forged.
Connecting Rods


Steel. (Bigger cross section and diameters) Cast.
Compression Ratio



10.2:1. LS and SC400 – 10.0:1
Induction System



Sequential multi-point fuel injection. Sequential multi-point fuel injection.
Port and Manifold design



Long high flow and tuned length intake runners with central plenum. Log type plenum manifold.
Throttle body


90mm 70mm
Valvetrain DOHC 4-valves-per-cylinder with variable valve timing control. Timing chains. DOHC 4-valves-per-cylinder. Single timing belt.  (less mechanical noise).



Direct ignition system with platinium tipped plugs (individual coil per cylinder). Distributor cap on the end of each intake camshaft.
Maximum engine speed (std)


6900rpm 6600rpm
Weight (engine plus ancillaries)


231kg (508.2 lbs.) 213kg (468.6 lbs.)


H: 710 mm
W: 800 mm
D: 640 mm
H: 660 mm
W: 700 mm
D: 710 mm


No adaptor kits currently available, however Nissan Patrol transfer case can be easily added to Infiniti gearbox Wide

Do you have any questions? If so, please head over to the forums to get a quick answer or share your experience!

This is a freelance site with no support by huge companies.  I have been doing most of the R&D and technical write-ups by myself with my personal money and literally thousands of hours of my time.  I have taken extra steps to demonstrate in details how things are done.  Currently I am one of the few people doing Lexus V8 research and performance enhancement.  This effort comes from my personal love for this wonderful engine.  Most of the modifications are from trill and errors.  There is no cookbook for the 1UZFE modifications and its a virgin territory for performance.  The parts, labor, web development and site hosting are from my personal hobby money.  If you feel my efforts help you in any form, please do not hesitate to donate any amount of money to support this site. You have no idea how much I appreciate it!

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