Last of the JZ motors ended production in the IS300 etc. (Lexus used it in two cars at the end, no use by Toyota at all after the Supra ended production in 98 officially in the USA.)
My brother's IS300 has the last version with the VVTi and it's a sweet motor to be sure.
You can find low mileage used JZ motors from these lexus vehicles that have never been modded, or hotrodded and are in excellent shape.
With some simple mods, those same used motors are very capable of 600+ at the wheels.
I think there are very few, if any 7MGTE's out there anymore capable of making 600hp for very long on stock internals. They are just too old, and worn out.
With the right mods, the 7M is a great builder engine. Reality is with similar mods, the JZ motors are just as responsive to the upgrades, and as we all know, Toyota designed out many of the compromises the 7M has built into it.
1) It was originally designed for a distributor located on the left side of the block. (not the head as is used later on the 7MGE version.) Your drain tube on the block that the intake cam cover dumps into? That's the hole where the distributor used to reside.
2) That distributor also was run off a shaft that drives the oil pump. There was a mechanical fuel pump located there too. (The J tube cover is where the pump was located, and there is a uncut mass of material where the lobe for that pump would be machined on the oil pump drive. There is also a disk of material that gear teeth would be cut to run the distributor as well.)
3) The crossover oil pump design sucks balls. (To get around it, you have to at least change how the oil exits the block, or go all the way and upgrade the way it leaves the pump too.)
4) Oil pickup design sucks. Pan design sucks. Both are resolved with some simple mods, but the basic setup has many flaws, and I'd wager the bulk of rock knock problems started with downshifting while under heavy braking.. the oil sloshes to the front of the pan/engine and uncovers the pickup, yet the engine is running at high rpm.. and there goes your rod bearings.
Things like the head design are the reality of the era they were designed for. In the early 80's, 200NA horsepower was very stout for a 3.0 I6. For the later JZ engine, 225 was considered OK. That 25hp difference played out in the turbo models too, 230hp v/s 320hp... stock rated of course, but everyone knows the rating on the last Supra was low on purpose.
But let's not split hairs. The new engine designs from Toyota exceed the JZ motors, and they should. They are new!
That being said, anytime you can get more displacment in a motor that is about the same size and weight of another is a good thing.
The best combination of price, size and weight is the aluminum V8 LS3 engines from GM right now. They are plentiful, cheap to mod and make insane power when under forced induction. (They flow great NA, and under pressure they make the most of just having two valves per cyc.)
I've done some measurements, and using the bell housing to adapt the R154 to the Holden V8 (AKA, LS3) this engine would be lower, and further back than the stock I6. It would be about the same over all weight when turbo charged with two turbo's. (Imagine twin GT35's on there... fast spool and oh, an easy 1200hp at the wheels.. from a 7L engine.)
Setting the engine back like this makes more room to run a larger FMIC and radiator etc. (Heck, the PWR or CSF dual core alloy radiators would work fine I'd think to cool this motor.) Keep your AC too. Or even better, bolt it all up to a new 5 speed auto, and get awesome gas mileage, and never have to shift again. Easy? Nope, but nothing is easy.
Would this piss off the "faithfull" MK3 owner? Yep, but the nice part is you just push more on the gas, and very soon you will not be able to hear them bitch anymore, as they will be too far behind you to hear, even with bullhorns!
Keep in mind, I have spent more on my stroker 7MGTE than it would cost to build a very nice GM V8 TT engine... so flame away!
I like the 7M, but I'm not married to it gentlemen. If there is a next time around on this motor, I'd go JZ if easy, or even better, I'll go LS3 based and really make some insane power to test the brakes on.
