Bump, I'm interested in this as well for my project truck. Edit: http://www.fallonz.com/archive/truck/20R.html I stole this from the 1st Google hit.
first and formost .. you MUST have a 81-84 22r block .. no exceptions , as the 85+ have a different deck height .. and is known as the "laser" block . so .. with the 84 <----- block .. you can now get to building . My first build consisted of , "sliping" a 22r block into a truck that already had a 20R .. so it was easy .. all things "bolted up " and no carb mods . depending on the year of the truck it's going into ... the "hi-bred" engine is a fairly simple mod .. what exactly do you want ? and why are you thinking of this ?
ya its pretty stupid easy if you take a 22r bottom end and a 20r top end you can increase compression, good for a NA motor. im in the middle of building one right now for my celica. if you take a 20r bottom end and a 22r top end you can make a lower compression motor, better for boost. this is what i have in my wagon, supposedly 6-7.1 compression ratio, but i never did the math... you can use a newer block, but loads of machine work have to be done. and if you do a ton of machine work to the 20r head and 22re plenum you can get them to play together. and NO, i will not instruct on how to do the newer block or 20re mod for 2 reasons: 1. ive never done it so i couldnt tell ya anyways 2. if you dont how to go about it in the first place you shouldnt do that extreme of a eng mod, i wouldnt. its better to throw cash down to have it done right.
i have done the 20r head on the 22r "lazer" block, sorry but im still in the process of getting it to run. and YES it cost me about 1k alone to get the head work done, but i also put extremely large valves in it.
The word through the dealership that I worked at was that the laser block motors differed not only with deck height but the lasers also had forged cranks and rods, I heard it was a result of to many dolphins cracking cranks.
All 22r/re have forged rods and crank. I believe the 20rs did also, but I've never had the bottom end apart on one. The one 18r I had apart also had forged rods and crank. These motors were way overbuilt!
