3UZ-FE Tuning Guide

G'day All. Looking at Lexus LS430/Toyota Crown Majesta and want to make 400-500 bhp. How good is the 3uz in these and what how much does it cost to get a reliable 400-450bhp. Budget is 10K AUD for the build. Is it possible?

Jasman,

That's not something I've attempted with the 3UZ, but hopefully a member here has tried it!

In my opinion you can make about 350-360 bhp with custom pistons and camshafts, ported heads, headers. Going farther than that in NA mode will cost you drivability- it will make 400+ but only at very high revs, where normal engine never lives, so it will be completely useless for a street car but showing up big number.

Switching to turbo is a different story. Yes, it will easily make 400-500 bhp but the pricing of such project can become much more than your budget considering everything you will need to buy strarting from ECU. I'm currently putting together 2UZ for 1200 hp and it comes out very pricey...

So if it was up to me I would go with first option - 350 enjoyable NA bhp)

3UZ being a v8 would be good for a supercharger build (5-6psi) but the thing is the parts are hard to find and the bolt-on Kits are extremely pricey. Speed Academy put a ford blower on ls430 but there's a lot of work to do.

Any type of forced induction would require an ECU to compensate fuel and ignition timing for additional air. That automatically brings up the question about handling automatic transmission which is an issue with Toyota. Staying in NA mode allows keeping stock ECU and not getting bothered with transmission handling issue.