So this project took a 180, or a 90, or a 270, something. I decided just to get the damm thing running, so I pulled the CRD out and went 4L to get it on the road........heres whats been happening with it this year:
With everything going on these days I decided to remove the Diesel engine from the MJ and just do the conversion as a 2000 4L/Aw4.
So I went to the junkyard because there were a couple of fresh newer 4ls I could pick from that were put out Thursday, I went the Saturday after and a couple were gone, but one was left that looked good. Engine wasn’t a greasy lump, interior was clean, and it was driving when wrecked so you know it at least ran.
So I pulled the engine and trans together. A few weeks later finally had a warm enough day to pressure wash it off, and then next weekend got the engine separated from the trans and onto an engine stand.
Well once the grease was off it turns out the bell housing is cracked. Dammit, so I need to deal with that.
So I get the engine on the stand, I was planning to reseal and clean it up. I had to replace the oil pan since they punch holes in them to drain them........dikks. So I have the pan off and I decide to check the bearings........ya they are scored, both rods and mains. Dammit.
I pull the head since my gasket kit came with a new head gasket. The cylinder walls are fairly polished, and have some vertical scoring. There is not a ridge at the top of the cylinder compression stole, but the scoring from the piston skirt isn’t great.
So after debating what to do, from honing cylinder walls myself, new rings, and then assembly to rebuild options, to just getting another engine, I decided on stroker.
Doing the stroker research you can see guys who get big power out of a 4L, but it comes with all sorts of other issues, knock, engine management, stand-alone engine management. Etc. most of the big power increases come from increasing the compression ratio, but with no knock sensor and no ability to adjust timing this is problematic on the stock controls.
After doing some research it turns out that some custom pistons were release in about the 2016 time frame. The combination of 258(4.2) crank, 4L rods, and custom pistons gives a 4.6-4.7, with a 9.3 compression ratio. Stock is 8.8. The “poor mans stroker” which has been the most common one I have heard of for years used the 258 crank and rods with the 4L pistons, to give a 4.6-.7 with a 9.6 compression ratio. The poor mans stroker uses the 258 rods which are about 5.825 inches, the 4L rods are 6.125. The longer rods give more favorable rod angles, and with the custom piston you can run the longer rods.
So I Decided on a kit from clegg, I have been trying to price out everything separately, but it doesn’t seem I can beat the price on the kit, and shipping is $75 for everything together which I’d likely go over shipping it all separate.
https://www.cleggengine.com/stroker-kits/jeep-4-0-stroker-kits.html
So I’m going to take the block to the machine shop next week, have them check the notes to see what size pistons I should go with, the smallest
Overbore I can do is .030 over.
Since I’m getting a new crank and recon rods the only machine work I need is the bored honed, and then the thing hot tanked to clean it up. I am debating if I should get it decked to clean up the surface for the head gasket, but am leaning towards not. Shop wants $40 to install the new cam bearings, which I am on the fence about, slightly trickery being down the long bore, I could probably manage, but maybe it’s better just to let them do it.
I am also debating the mildest cam I can buy, I don’t know how bad mine is worn, and since I want new lifters anyways the cam becomes a little more cost effective.
So that’s the plan for the stroker bit. From my research this should give something about like 220-230 hp, and keep me away from higher octane gas and the exponential effort of going for more HP.
Once I get the engine, trans, and transfer case together I am going to install them, and then start digging through my boxes of parts for all the other junk to figure out where it needs to go, and then start seeing what I am missing.