As I have written about many successful engines during the last few months, I thought I would continue the theme with one on the Lexus V8. I wasn’t that intrigued by these engines until I read an article about drag racers dumping their Chrysler Hemi’s in favour of a lightweight Lexus V8!
Lexus have produced two versions of their V8. The first, codenamed 1UZ-FE, was a 4 litre double overhead cam with 32 valves producing 250hp. It was introduced to the market in 1989 fitted to the first LS400 luxury saloon. The engine has hypereutectic pistons. This means that the piston heads are manufactured with a mix of aluminium and silicon. This is because the inside of the cylinder reaches temperatures of up to 600° Celsius. Aluminium expands quite a lot when hot and so needs to be designed to be loose when cold so that they have room to expand.
By adding silicon, it reduces the amount of expansion so Lexus were able to design a snug fit for the pistons that provides better efficiency in cold conditions. It also prevents the piston scarring the side of the cylinder, which ultimately causes an engine failure. So this was important for improved reliability.
The engine was originally an Indy racing design, although it made it to road use first in the LS series vehicles. By 1995, it had gained lightweight conrods and a revised output of 260hp before gaining Toyota’s variable valve timing in 1997 and an increase to 290hp.
Lexus/Toyota also released the 2UZ-FE, a 4.7 litre version designed for low revving environments like the Toyota/Lexus 4WDs such as the LX470 and Land Cruisers. It had a cast iron block instead of the aluminium 1UZ version and hit the market in 2003. The 3UZ-FE was another version of 4.3 litre capacity. This engine went into the LS, GS and SC 430 models. The UZ series engine was replaced in some Lexus and Toyota models with the UR series from 2006 and like the UZ, it was manufactured in several versions.
The 1UR-FSE is a 4.6 litre V8 that went into the LS460s apart from certain markets where the models had a slightly different version – the 1UR-FE which didn’t have direct injection. A 5 litre variant, the 2UR-GSE, was made for the ISF sports saloon pumping out nearly 420hp and another 5 litre version is the 2UR-FSE which is used in the GS Hybrid, although with combined electric motors it delivers more power than the ISF!
Lexus has also developed a 5.7 litre version known as the 3UR-FE, which is used in the LX570 and other trucks. Like many of these engines they were manufactured in Japan and also the US factory in Alabama.
Finally, Toyota Racing Developments have applied their magic to several of these variants by developing superchargers and other performance parts to make them more enjoyable! During 2015 Lexus in Australia seriously considered entering the Supercars series, however the parent company opted for another path: GT3 racing with a V8 powered RCF in Europe and the IMSA series in the US.