Corolla 3k block with 4k crankshaft?

[MarkIIRx12]

Hiya

Im doing a old 1.3L 4k engine, had some new parts laying around so i figured to put on new rings and stuff while i had the engine out. I found out the cylinders have deep rust so its really just a waste to put it back in. I have a nice 3k block laying around tho, so was wondering if i could use that block with the 4k crankshaft and pistons, i have read the blocks are identical but the stroke on the 4k is a little larger. Is this correct? i havent found any info about how much longer stroke the 4k has tho, so i dont know if it will work with a stock head and everything.

Anyone has some info or suggestions on this? Help is greatly appriciated

[crostek]

Hi
Yes it can be done I have one myself
There are some clearance issues with the rod hitting the side of the bore, near the bottom of the cylinder. This can be solved with a small bit of grinding,
I am pulling my engine down soon for a rebuild and take some photos for you if needed
also see rollaclub website for more info

[Lost Momentum]

Bearings on the crank & the rods are the same. That's the easy bit.

The top of the rod bolts will hit the bottom of the bore (as stated above). The nut on the rod bolts will hit the side of the block right at the sump where it attaches to the block. To relieve this is just some grinding of the block and to heat up the sump and tap a little clearance hollow with a ball peen hammer. It wont need much, but don't go overboard as you do not want to distort to block/sump facing.

The next big step is...you need to grind some of the counterweights off the crank. And then you need to rebalance. From memory (25 years ago!!!) the TRD pistons we used poked about 5mm above the block. We ended up taking some material off the pistons to get our CR down to reasonable levels.

I have pics of the engine only in completion, not in the construction phase. Shame really.