Topic: 22R head swap

[Steve-44]

I have a 22R in my DD that just broke the timing belt.  The belt and all the associated parts are less than 30k old.  I haven't pulled the head yet, but the previous owner told me it's a tolerance motor so the valves are likely bent.  1st off, is that true that the valves are gonna be bent?  If so, what else will need to be replaced in the process?  The main question though, is what's involved in putting on the 20R head in place of the 22R one?  I have a built 20R in my project vehicle that won't be ready for the trail any time soon and I've heard that putting the 20R head on a 22R block is a pretty common power upgrade.  So if its a simple swap, I thought I'd rob the built head for the broke one and then fix up the broke one later.  Any insight on this swap and pros and cons would be great.  Thanks guys!

         Steve

[79coyotefrg]

well, its achain not a belt,  and chances are if it broke going down the road its got bent valves

a 20R head will bolt right onto the early 22R blocks 84 or older

[Marlin]

Since all 20, 21, and 22Rs are interference motors, your valves are most likely bent. How fast was it spinning when the chain went south? The slower, the better your chances are for less damage.

To check for bent valves, turn the crankshaft until the timing mark is at 3 or 9 o'clock (this will position the crank away from top dead center). Next rotate the camshaft and check for excessive valve to rocker arm clearance. This will immediately show the bent valves.

What year is your 22R? There are two families.

1. 75' to 84'   20, 21, and 22R's
    98 row timing chain  thick head, and tall block.
2. 85' to 95'  22R's
    96 row timing chain  thin head, and shorter block height.

A 20R head will therfore only fit an early 98 row motor without added modifications.
Putting the 20R head on a matching 22R motor will raise the compression from 8.7 to 9.7 to one.
I have done many of these conversions with great results.

[yotaweelr]

it's broke... it was running when it happened. they are bent. usually all the intakes.

[Steve-44 [OP]]

well, its achain not a belt,  and chances are if it broke going down the road its got bent valves

a 20R head will bolt right onto the early 22R blocks 84 or older

   Woops!  Brain fart on the "chain" not a "belt" thing.  I know its not a belt.  It came out that way while I was writing.     And I was crawling along over the rocks at about 1/2 mph and 800 rpm when it died.  No sounds or noises or anything when it happened.  I thought I just stalled it.  I've got a borescope t check it out, just haven't done it yet. 
   My truck is an 83 but its the 2nd gen body, so I guess late 83.

[BigMike]

Gotta be a Nov or Dec of 83 then. It will have the early generation 22R (tall block) if the engine has not been changed.

Nice tech Marlin

[4inchToyotas]

If you've got the 20r head already built, itd be worth it even for the short time to put in on the 22r block (assuming it's the tall block of course). When I redid the top end on mine I sent straight for the 20R swap. Made a heck of a difference just using stock valves and cam. And when I went large it was really sweet.

[beater82]

Anybody have any horsepower/torque numbers from the 20r head swap? I heard you have to swap in the larger 22r valves to make it worthwhile. Anybody runnin' these hybrid motors with alot of miles on it? I live in a smog exempt area and have a standard bore 82 block sittin' around so I might be into this.

[BigMike]

I live in a smog exempt area and have a standard bore 82 block sittin' around so I might be into this.

No offense, but If you live in a smog exempt area, then why are you still toying with the R engine?

Man, what I would give to not have to worry about smog.....

[beater82]

They're reliable . I'm also tryin to buy a house otherwise I'd probably do the supercharged 3.4, $14,000 in dynatrac axles and 42" tire thing.Gotta' get the kid some braces too

 Yeah, I left San Jose last year due for a smog check and my registration a week out with a weber, cam, header and no cat. Just in time. $40 every 2 years in oregon. No smog.

[BigMike]