I'm in need of jeep/amc 4.2 crankshaft casting #3727 1987-90

Also looking for 4.2 rods. Best deal so far $23 each

The parts stores show crank kits but none can order them. I'm not wanting to spend $447 on a scat stroker crank and best deal I found was $330. Parts stores price in the $250-280 range where I would like to be but they can't find one.

Just looking for best deal on stroking it?

 

Your to far away and you dont have a big enough crank.

 

Your kits you see is probably the best deal because of the crank. I did all mine separately and I'm a litter over the kit costs

 

Scat stroker kits are about cheapest you can buy and still have a little quality.

 

I stroked mine about 6 years ago. I would not do it again. More torque is nice but not worth the other issues it caused. I have talked to plenty of other people with the same experience as I have had. Heat will be a bigger issue now on the trail. Heat issues were not noticeable on the highway but on the trail they have driven me crazy. I originally went with an aluminum rad but the epoxy at the tanks started leaking early on. This was not covered under warranty. Make sure you get a rebuildable aluminum rad if you go aluminum. I ended up going with a custom copper unit. Very pricey. The high flow water pump does nothing. I do not recommend it. I put in a ford Taurus electric fan which helped huge. Strokers are notorious for eating cams. Break it in carefully. I have not had any engine reliability issues. I attribute this to having a race shop put the bottom end together. I highly recommend this. Dino Savva has a lot of good information on building a strokers on the web. I also added a unichip piggy back computer. I'm on my 2nd now. This will help with gas mileage. All in all it has been a great learning experience but not one I would recommend. I would suggest going with a V8 but I'm sure it would bring its own challenges. If you do this right it will be very expensive and in the end in my opinion not really worth it. I did the full meal deal with header, larger diameter exhaust, computer, radiator, water pump, electric fan, you name it. I have talked to many people at jeep events and they have mostly the same experience as me. If you go ahead with it have fun and expect it to be much more expensive than you expect. The money will not stop at the engine alone.

 

I bought a built one (golen) and i've loved it. I put it in myself but i wanted a warranty and the guy has built thousands if them. I have a flow-master water pump, hesco highflow housing, champion aluminum radiator and a generic universal electric fan ( which sometimes works and sometimes doesn't). I also replaced all my lines etc. The motor does get warm quick but it rarely goes about 210. In Moab in the summer, there was a few times where it got really hot and boiled over when I shut it off. Definitely not a huge issue for me with the power I gained but can be annoying. I'm going to try one of the built desert racing rads w/ the three e-fans down the road.

I went with AFE headers, 3" exhaust (spun cat/flow-master 44), 24lb Accel injectors, 62mm TB, Accel Coil, browndog mounts/brackets, removed the AC for pulley, and pretty much replaced everything else except the alternator. I also got a HD torque convertor to handle the load... (probably wasn't needed)

It was expensive because I bought a built one but I love it and don't regret it. Everything is still the same to wrench on, I didn't have to fabricate anything, and I gained a ton of power. Being as ive had no problems/broke it in properly, I expect it to last quite awhile. Just be sure to use a High-zinc oil (I use Amsoil zrod).

 

I'm not worried about heat or any other problems. Enough people have done stroker without problems. I just looking for a refurbished crankshaft. Right now my best option is a $456 scat crank that comes without bearings.

I've found pre 87 refurbished cranks but they would require milling the front 10MM.

I don't know if this requires them to be rebalance afterwards?? I've seen guys talk about using a spacer to get balancer in the right spot to have pulleys in line but this doesn't make sense to me because if it's too long and the serpentine pulley isn't going to go on far enough without milling I don't get how a spacer will help.

If anyone knows how that works I could order a refurbished crank for $340+$25(spacer)=$365 instead of $456(crank)+60(rod/main bearings)=$516

 

Please don't take this wrong but if you start worrying about a few bucks for parts before you even begin your "Stroker" perhaps you need to rethink the engine build. The most important part in any stroker engine is the rotating assembly crank, rods, pistons then balancing them.

Any stroker will cost you more in upkeep and parts than a stock setup will along with the fact that premium fuel will be required because of the CR along with that higher heat issues to be addressed.

I considered a stroker for a short time along with an engine swap but finally decided on neither one and to do a "New Stock" rebuild using all race engine specs and machine work instead. Using all new OEM or better parts for the build and built by a race engine rebuilder of 1000's of engines to do the work.

The 4.0 was a great engine and all I plan on is refining it a little like they could not do during an assembly line build.

 

I agree on the few bucks thing. I talked to a vender about the scat cranks and got a sweet deal. $470 shipped with king bearings.

I just wanted a refurbished 4.2 crank and could only find the older ones with too long a crank snout.

Was just hoping to find a lead in a 87-90 crank refurbished for a good deal.

I don't think there is as much of a heat issue as some people make it out to be. Compression is gonna be 9.49 with my piston/rod combo. I don't mind premium.

I didn't want to go back stock as the almost 100ft lbs of added torque is something I want to have.

I figured if I'm gonna rebuild it might as well do it how I wanted.

Plenty of guys running poor man strokers without issue. Lots of people seem to jump on the band wagon of if your building a stroker you can't do it cheap and reliable without buying the best parts available. I just don't believe that.I know guys running strokers with no issue using refurbished cranks and rods.

I think the popularity of the 4.2 crank in the 4.0 has caused parts store to not be able to order cranks.

So good luck to anyone looking to go that route.

The scat cranks will be going up in price first of the year so if your considering it, I would get that crank ordered ASAP.

I'm ordered mine today from Clegg machine. Kevin was very knowledgeable and let me pick his brain on my compression and few other things.

If anyone is looking for a refurbished crank and find a good source for the 87-90 4.2 crank casting number 3727 post it up to help others interested.

Really the best single upgrade for some more inline power out of your 4.0