here's the deal, did a rebuild on an 84 22re engine stuffed it into my 87 4runner and that's where the trouble began. found out 84 and 87 engines have lots of differences......timing chain, chain cover, head, block, pistons, exhaust manifolds, oil pumps, etc. i swapped my gauges to a sr5 model (also swapped oil pressure sending unit). my concern is that i installed a 87 oil pump on the 84 block and the oil pressure gauge is not registering any oil pressure. i called around the part stores to verify if they were the same part number, and they are not. my question is if anyone has ever done the same swap and if the oil pump is compatible? other question is if the 84 exhaust manifold is longer than that of an 87 because if drill a hole to the 87 to fit the 84 head but still getting an exhaust leak at the bottom of manifold and where the pipe meets, i'm guessing because the manifold is shorter which tilts the pipe to a certain degree preventing from seating straight.
any feedback would be appreciated.... thanks

 

When an engine swap is performed, a person usually uses everything from the "new" engine to make the swap less of a problem.
Why did you use the pump from the 87? If the pump was bad you could have picked up one in a parts store. Did you get the 84 engine bare?
I think the 84 has a dual-roller timing chain and the 87 has a single roller. i could be wrong though.
Do you still have the old parts from the 84 engine?

 

my 4runner is an 87, took the oil pump out of it. when i began the engine rebuild i thought the heads were similar. come to find out, the 84 heads has swirl type ports unlike the 87--kidney shaped. so i had an complete 87 engine (with a bad head that had been decked below specs) and a good 84 head. before this knowledge i had the 84 head decked, pressure checked, and valve stem seals replace. trying to install was a pain, 87 chain too short, 84 chain bare got any tension--tensioner was all the way out, then come to find out, LC Engineering told me the flat top pistons of the 87 block with the 84 swirl head would a rough compression ration of 7:1= no power. located an 84 block (84 california 22re only use single chains, while the federal 22re's use the double chain system) and installed. but the oil pump on 84 is bad. i though i could save a few bucks (100) using my 87 oil pump, they bolt up, look identical (except that the 87 is slightly thicker). i thought maybe my gauge is bad.... i read that one could find out if there is oil pressure by disabling the ignition system and cranking the motor with oil filter out