huygens

2010 JK Rubicon 3.8 auto. Bent #5 cylinder valve. Drove it to a shop I deal with locally thinking it was an electronic or electrical problem as it was running bad and missing and I did not have time to deal with it. $500 later and they chased the problem down to the bent valve and indicated that the valve contacted the top of the piston thus the engine needs replacing at ~7k. That's north of 50% book value. Had it towed home and set off the side of the driveway. Scratching my head on what to do with the thing. It's worth fixing, but not to put the same engine back in it at that price. Not a fan to begin with of the 3.8, way too under powered.

Not willing to spend the what a hemi upgrade would take (I see low end if I were lucky North of $10k and an insane amount of work and modding, high end if I pay someone $20k). I want some more power so I can keep up with traffic but I don't plan on racing the damp thing.

Saw 505 has done a 4.1 stroker kit for the 3.8 (kit is ~$3k, rebuilt engine at 4.1 is ~$6k plus core for bad parts) anyone know anything about that? On the surface that seems more reasonable, much more hp and torque and just bolts right in. They have a number of other options in between too. Uncertain if that is the way to go either, again it is the same engine, but then is it?

Thoughts, options? Take your time, no rush, the Ruby isn't going anywhere for a while.

Seizer

huygens

> If you have the time, tools and gumption you could pull the head. Install new piston plus rings. Take head to machine shop have them hone it and change the bad valve.

The shop indicated the head was not salvageable and would require replacement. They said that with the valve contacting the piston, the crank bearings (?) stood a serious chance of being damaged and not worth the risk. Plus 120k ish miles.

> Bent valve. Hmm isn’t that usually a sign that something went wrong with your timing?

Apparently not as I drove it from where it abruptly started running like shit home then to the shop later that day.

> I’ll advocate for the 2.8 Cummins crate engine.

I love the ideal of a nice simple 4 cyl diesel under the hood. I pursued this ideal a while back when I bought the jeep. If I recall we are talking somewhere in the price range of $30k (?) to pay someone to do this. Not reasonable in my book unless someone can turn me onto better pricing. I think the crate engine alone is $8K, no? Plus I have the auto trans which I gather has to be replaced for the Cummins (and pretty much anything else I might want to put under the hood). I will look into it some, but I am pretty sure cost is going to kill this option pretty quickly.

What pricing have you seen for the Cummins swap?

karls10jk

The 505 stroker gets poor reviews, but there are only a couple reviews posted, so it could certainly be biased the wrong direction. I've read through the threads and most people seem to have picked a package too hot for what they need and it seems that the tuning isn't there to support it. A user got it tuned and he said it's been great. There was a thread recently where someone claims that the rebuilt motor they received had a bunch of mismatched parts in it.

Again though, with so few reviews, it's tough to get an honest gauge on what's happening. There could be hundreds of them out there and we never hear about it. I keep up on these threads because I'm at 174k on my 2010.

TOTL Innovations

You can get average mileage drop outs for under 1200 from people who did LS or Hemi swaps. That leaves a lot of budget to just replace the motor so wondering how you got quoted at 7K.

If you want to upgrade a 3.8, I would look into a supercharger.

If you are skilled, you can do a hemi swap for right around 10K. Google that and there is someone who has done it and provides tons of info on how to do it for that budget.

TheDirtman

The 2.8 Cummins is around $12k for the crate, computer, wire harness, and you still need to add the transmission and adapters. People that are doing the swap hits the $20-25k about the same as dropping off at Motech and getting a 6.2LS Axis industries near Kokomo, IN has a website and can give you a quote. The 2.8 is also not smog compliant in a 2010 if you have to smog.

jedg

If you decide to go with another 3.8L, TOTL is right. Places like MoTech have 3.8L engines pretty much all the time. The last time I was at MoTech, I counted no less than 30 rigs in their shop (that was November) so I'm sure those folks are looking to recoup some cash by selling that pulled 3.8. That won't scratch your itch for more power, but it's probably the cheapest you're going to find.

huygens

I actually called and spoke with Zach from 505 today on the topic. Interesting conversation and was open about some problems with engine installs. He referenced issues with shade tree and do-it yourselfers not understanding the dynamics of a punched out engine, need for performance tuning, etc. Doesn't necessarily explain some of the things I have seen online regarding mis-assembly, but I do understand the whole performance tuning aspect of a stroker engine and could see someone thinking this was a drop in kit and not following through with a lot of the after install work. His comments were in line with what I spoke with Shawn at JD Jeeps about regarding their diesel conversion with a 4BT. Shawn referenced similar issues with do-it-yourselfers not understanding what they are taking on. I will probably make a few more calls, but I think the diesel option, although very desirable, will be moved back on the list of options due to costs at least for now. I have the 42RLE automatic transmission which apparently does not bolt to any other engine on the plannet except the 3.8, so unless I want to buy a transmission as well, my options become very limited: rebuild current engine (stock or performance), replace with rebuilt engine (stock or performance), replace with a used engine out of a wreck or from someone that did a swap and has an engine they are willing to sell. I will keep posting what I come across and will keep watching for your recommendations.

huygens

TOTL, shop I took it to was quoting me a rebuilt engine, they would not do anything outside of a factory swapout. That option, of a $1200 used engine is becoming more and more appealing. With a set of headers while I am at it and possibly a couple of other simple mods, I might get close to what I want at the same time. Then I can take my time and plan my next move, either sell it or start buying parts slowly for the proper upgrade so it does not hurt all at once.

huygens

Jedg, I will look motech up and give them a call tomorrow/next week depending on their hours.