Toyota’s 2ZZ-GE engine is a very solid and powerful 4-cylinder engine capable of outstanding performance at the race track. If you want it to perform reliably here is what needs to be addressed:
Oil pan – the stock oil pan holds just over 4.5 quarts and has no internal baffling. As soon as you start to go around corners, especially on R-compound rubber, the oil will slosh away from the oil pick-up. If you do that enough times or even just once in a long corner the oil pressure will drop and you’ll be looking at an engine rebuild. To avoid this expense and inconvenience we strongly recommend upgrading to the Moroso oil pan. Your oil capacity will increase to 6 quarts and the Moroso pan’s active internal baffle system keeps the oil right where it needs to be: around your oil pick up. The Moroso pan also has provisions for an oil temperature sensor (important) and a turbo oil return.
1ZZ/2ZZ Moroso Pan
Oil pump gears – The 2ZZ’s stock oil pump gears have a reputation for exploding if the engine is overreved (most commonly during a misshift), if momentarily starved for oil (see pan info above), or even sometimes for no reason at all. If you plan to run your 2ZZ hard then installing upgraded MWR billet oil pump gears is cheap insurance.
MWR 2ZZ oil pump upgrades
RPM – “Bro, I’m going to rev to 11,000rpm – it’s gonna be sick!”
Well, the 2ZZ loves to rev but it has its limits. Our oil pan prevents oil starvation. Our oil pump gears prevent pump failure. But the 2ZZ’s oil system has inherent flow limits which cause cavitation and pressure drop off at extreme high RPM. If you’ve got a few thousand dollars and a talented fabricator you can have a dry sump system built; otherwise, for good durability, we recommend a maximum of 8600rpm sustained and 8800rpm for short bursts.
Oil Temperature – If you have a Toyota car then you do not have a factory oil cooler which is a problem if you’re racing around a track for 20+ minutes at a time – oil temperatures can quickly reach 300F+ which means thin ineffective oil and angry rod bearings. Lotus OEM oil coolers are normally adequate – monitor temps and try to stay below 260-275F (depending on oil type and weight)
MWR Oil Cooler Kit – Toyota MR2 Spyder 00-05 All
Valvetrain – the 2ZZ’s valvetrain is very impressive, allowing an 8250rpm rev limit from the factory. It does not last forever under these conditions unfortunately; broken valves and even valve springs are common in stock 2ZZ’s that see extended usage at 7000+rpm and these valvetrain failures often lead to complete engine failure, a near total loss. By upgrading your cylinder head with MWR valves and springs, and optionally titanium retainers, you get a valvetrain that is much more under control, lasts much longer, and can safely rev well over 8500rpm indefinitely. Consider a cam upgrade or a port job to pick up some horsepower while you’re in there.
MWR 2ZZ valves and valve springs
MWR 2ZZ cams
For severe duty with forced induction, consider Ferrea valve set which includes Inconel exhaust valves
Pistons – the stock pistons hold up just fine on naturally aspirated 2ZZ’s and on low boost factory supercharger setups. If you’re running increased boost or are racing in extremely hot conditions you may find that the stock pistons’ 11.5:1 compression and relatively weak ring lands are not capable. The result is excessive blowby and scored cylinder walls or worse if those ring lands fail. Upgrade to 10.5:1 pistons for a significant increase in strength as well as a much more forgiving compression ratio that will allow you to really increase the boost and run the engine hard without fear of detonation. Planning on more than 15psi (1 bar) of boost? Go straight for the 8.8:1 or 9.0:1 pistons for outstanding power handling.