22R timing chain nightmare

[rddrgn1]

good evening gearheads - anybody out there want to be a hero?? I'm a mechanic in s.e. washington, and a friend of mine recently came to me with a problem that has me (and every other mech. in town - INCLUDING the local toyota dealership) at a total loss. he recently bought an '85 toyota pickup with a carbureted 22R motor, minus the timing chain, and asked me if i could put it together for him. as i have done several 22R timing chains in my 30 years as a mechanic, i didn't see any problem with re-assembling a basket case. (the nightmare begins). apparently the last owner had the timing chain replaced, and it ran for 1 week and threw the new chain. as some (or most) of you know, there are 2 different 22R blocks - 1 short - 1 tall - and a single or double roller chain. research tells me that the change in deck heighth happened in 7/84 and the pickup has a build date of 9/84 so it is possible, i guess, that it could have either engine. i first determined that it did in fact have a 22R motor according to the stamped boss on the drivers side of the block, and that it took the single roller chain. on further investigation, through measuring the timing cover, and matching the gasket set, that it does have the short block, and the last "mechanic" put in a tall block chain (verified by the chain, guides, tensioner, etc. in the "box o' parts" :-) in the bed). this explains why it threw the chain. so i got a short chain and installed it. unfortunately it is TOO short - it goes on, but it's too tight to install the guides, the tensioner, OR the timing cover.(it fits like an american v-8 timing chain - straight up, straight down, and tight) after getting 3 chains, from 3 different sources, the last one being a complete set (chain, gears, tensioner, guides, etc.) from beck arnley worldparts and having them all fit exactly the same way, i.e. the long chain is too long and the short chain is too short, i conclude that it's not a problem with the chain. unfortunately, i don't know where to go from here. after talking to several other mechanics, including the aforementioned toyota dealership mech i haven't been able to get anyone to say how this is even possible. does anybody have any advice, or know (or know where i can get) the specs on the distance between the the cam center, head gasket interface, and the crank center so i can at least tell which one is wrong? any help would be appreciated, as i don't have enough hair left to be able to afford to tear any more out. again, thanks in advance for any light anyone can shed on this "little problem" of mine.
jim, from dixie (rddrgn1)

[alltrac165]

Perhaps the head and block are different years? Like a laser block with an early head?
See this link for which head is which and block dimensions. I can't remember what the height of the later head is.
http://toyotaperformance.com/4_cyl_tech.htm
The engine you have should be an early block without the boss on the side and have round exhaust ports.

[rddrgn1]

thanks for the info/website - i guess i now have my answer. i have the late model (laser) block, and round intake and exhaust ports, which according to the tech page means that i have a 75-80 20R head. which means, i guess, that we all know what they're talking about when they say "will not swap without extensive modifications".

[johnfoster75]

You made my noisy valves seem pretty easy and insignificant...thanks!!!!

[alltrac165]

Bummer. At least you should be able to get a head cheap.