Also when retorquing the head - DO NOT LOOSEN the head bolts first, just torque them down tighter....
I would recommend lightly hitting the top of the bolts with a punch/hammer to "loosen" 'em up before retorquing them. Sometimes I've had bolts register proper torque when simply tightening them, and I guess this is because the bolts have not moved for a while and the oil down on the threads has gotten heated/cooled/heated/cooled so its gooey or something.. So I always wack the head bolt a couple times and then I put the torque wrench on and torque it and the bolts usually go a bit farther before reaching the proper torque.
There is also the newer Supra motors JZ motor series which might be adaptable to the W56. Some poeple say its possible and others say its not
WOW
I hope this is NEVER done. Even the 'R' series transmission would be a poor choice behind a JZ engine. 320 HP with only stock boost can't be good for any 'R' trans, even a rebuilt one from Marlin. Those engines, like the RB26DETT, make a good 400+ HP with increased boost right out of the box. And remember that the 'R' trans's life ended with the 7M-GTE; the JZ engines use a 6 speed transmission which is stronger than even the 'R' trans.
I just don't think the 3RZFE (34% more HP, 25% more Torque) is worth the trouble..........So that basically leaves me with the 7M-GE. This motor would be an increase of 77% more HP and 32% more Torque.
There is NO way that I am going to sit here and tell you that the 3RZ is better than the 7M. For sure the 7M has and will make more HP than the 3RZ, despite only developing just 11 more ft-lbs of torque, it is a more powerful engine. I would imagine that the 7M is more of a "rev-happy" power engine and the 3RZ is more of a "grunt" power engine.
But some other things to consider.......
7M benefits:11 more ft-lbs torque.
Cheap.
Easy to find / Pull it yourself at wrecking yards.
3RZ benefits:Much much improved OBD-II system.
Far easier to trouble shoot using a scanner.
Technology is leaps and bounds ahead of the 1986-1990 7M engines.
Lighter.
Cheaper tune-ups.
Maybe more fuel efficient? I don't know what the 7M will do in your truck but my 2.7 can pull 20-21 mpg on the freeway if I keep it under 75mph.
It's cool when a 4cyl is faster than a V6.
I'm sure most of that doesn't concern anyone, but I am really into the newer ECM system of the 3RZs. It's alot smarter than the older EFI systems, yes its more complicated, but also there is wwaayy less clutter and stuff on the engine too, so I think that goes both ways. The sensors are smaller and more compact and should last longer/less trouble prone. The air sensor on the newer engines would be my only complaint as the older air boxes and MAP sensors were just very simple and were great to use on dusty trails.
On a side note, the newer '05 2.7s are rated at 164 HP (5200rpm) and 183 TQ (3800rpm) which is 46% more HP and 29% more TQ, up 12%/4% respectively from the previous 2.7s, but getting ahold of a '05 engine would be a pretty penny. By this time next year they will be all over the place.
Keep us updated here with your progress and post some pics!!!
No doubt you will love the power of the 7M and it will be well worth the work! I know I love the difference with my 2,7 and it's definitely worth the work!
Regards,
BigMike
