Topic: 81 with a 20R?

[yotacorps81]

I have an 81 pickup with a 4-speed and I believe a 20R. I base that off of the exhaust manifold having only one stud in the middle and not two like my 86 4Runner's 22re, but I'm not even sure if that is a tell. I've seen aftermarket headers for the 20r with both stud patterns. The stickers are long gone off the truck so no help there. How do I tell what motor and tranny are in it?

[Nimyad]

Look at the build sheet under the hood or on your door jam. If it hasn't been messed with

[yotacorps81 [OP]]

The build sheets are both gone.

[steveco.]

Check the block. Should be a flat section on one of the sides that identifies it.

[Travis H]

^^^ its located right near where the dipstick goes into the block.

[Rocksurfer]

Also the first generation 22r's are different than the 22re including the heads so the exhaust will be different than your 22re.

There were 2 versions of the 22R/re the early tall deck and the later short deck. The short deck has a slightly lower block than the tall deck. The short deck uses 2 less links in the timing chain. There are also differences in the head that make the head from a long deck incompatible with the short deck and the same goes with the other. Now a 20r Hilux head is compatible with an early 22r which is actually an upgrade in power when you combine the 22r block with a 20r head. An 81 comes with a 22r so if you have a 20r it has been replaced. As mentioned above just behind the oil check stick there will be a flat spot clean it off and it will tell you what you have.

[kneedownnate]

20r manifold has single large outlet, 22r manifold has a dualoutlet

[Rocksurfer]

Not if the 20r/22r hybrid swap has been done, better to check the block of the engine.

[emsvitil]

20r valve covers are rounded
22r valve covers are angular (I know late 22r valve covers are angular, not sure about early)

[Rocksurfer]

First gen 22r's look just like 20r's

[Sparkplug]

Intake holes be round and block will say it. Carb can be swapped and so can manis. It would also have dual chains in 81 so that wouldn't be a way to tell either. Early 22rs had rounded valve covers also. They DO NOT have the Mickey Mouse looking casting at the bottom middle of block on pas side.

[Sparkplug]

By chance is the 4 speed in it side shifting? Ie the shifter doesn't come straight out the top. Your truck should not have a 20r from the factory if its a real 81

[wakkjobb]

Why not? 20R came in 79-83 far as I know; 22R started in... 84? Came in Celiacs before trucks IIRC; but when I think 1gen Yotas I think 20R always. 20R intakes are pear shaped and there is a ton of info on this "out there" so it'll be easy to figure out what you have.

Post pics if you can; we all love pics.

[Rocksurfer]

The answer to that would be no, 80 was the last year for 20r, 81 was the 1st year of the 22r.

Engines...
20r:    79-80
22r:    81-87
22re:   85-95
22rte:  85-87 (came out late 85 in some trucks and then 86-87 in both trucks and 4Runners)

Trans...
L43:    1979-1980  (4 Speed)
L45:    1981-1982  (4 Speed)
L50:    1981-1982  (5 Speed)
L52:    1983          (5 Speed)
G52:    1984-1987  (5 Speed)
G54:    1984-1987  (5 speed)
R151F: 1985-1987  (turbo pickups only)

The 85 turbo's were actually early 86 models released late 85