She turned 100k last week and started knocking last night. I'm thinking of either a v8 swap or a 505 stroker kit.
Currently has a Diablo tuned RIPP modified vortech supercharger so am thinking of just rebuilding with the 505 kits. Does anyone have experience or opinion? Super-Rubi is my b/u and not a DD. She can go 80mph straight as an arrow on 37's though and, likely why it's knocking.
Budget is a concern

 

A few thoughts: Suggest trying to find the source of the knock, it may be something easy. Lots of possibilities including things like the timing chain becoming worn with the slack hitting the front cover. Another test is checking the oil pressure with a gauge, one quick way is with an adapter that fits between the oil filter and the engine. Dropping the pan is easy enough, and so is removing the caps on the con rods to check/replace the bearings. Oil analysis is always an option too.

I've never heard a 505 stroker success story, quite the opposite actually. That's a big red flag to me. V8 swaps are spendy. V8 swaps can also be buggy and hard to troubleshoot the electronics and firmware -- For example, trying to figure out whether a problem is with Mopar, GM, Motech, or the wiring in between the electronic modules. Two of my best friends have GM V8's and love them, but the costs add up fast and it doesn't sound like what you want since budget is a concern. If the current 3.8L engine is toast, it's not from the 37's if it's geared right -- Maybe the supercharger boost was just too much? Curious how much boost it ran, and did it tend to detonate (ping)? Presuming the engine is due for a rebuild, maybe just rebuild it and turn the boost down a bit ??? Also curios what oil you ran in the engine?

 

About 8psi boost at 3k and it doesn’t get driven hard often but is built to take it when it does.
the oil press runs 20 at idle, normally hits 45 under load at 2500rpm. After the knocking and rattling started last night the oil pressure jumped around from 30-60 under load and back and forth without change in throttle.
I haven’t pulled the covers or used a scope to locate the sound though. I’ll check my next days off and post back here what I find.
I haven’t heard anything good about any swaps but was hoping for a glimmer of hope from someone. Your friends seem to be the norm. Thanks

 

It's nice that you have an oil pressure gauge!

If it's rod bearings, which is my bet with that oil pressure variance, they are quite easy to replace if the crank journal isn't (badly) scored. A set of rod bearings are cheap too. Might be best to pull the pan and not run the engine further. The odds of the fix being just replacing the rod bearings may not be great, but it's quick to pull the pan, wiggle all the con rods, and if there's a loose one or two -- pull the rod caps for a look. Caps are matched to the rod, proper orientation is essential, so mark them before disassembly.

On a side note, I'd recommend a minimum of 5W-40 synthetic oil with a supercharger.

 

Ill pull the pan before I run it again, good idea. I'm not an engine guy but can figure a wiggle bit.
I run royal purple in everything, used to think it was cheap insurance until this last year. Still good insurance but the cheap is gone.

 

Pulled the pan and found play in a connecting rod, just one. picked up a set of mahle cb1410a and there is still the same amount of play after cleaning it all up. The bearing that came out was well worn, the crank looked okay, but the bearing was spinning so I think the damage was to the cap and rod end.
Looks like my only option is to pull and rebuild or swap to a mopar v8. It had overheating issues and coolant consumption issue at 90k so Im leaning on a swap and modify the vortech s/c to the new power plant.

 

Figured it was rod bearing, too bad the bearing spun in the rod. Sounds like the problems started at 90K, how many miles were on the supercharger before then? What viscosity oil were you running?

 

I ordered some .25mm and .50mm bearings just to make sure the PO hadn't already ground the crank. There's a ton of slop after the new ones went in and the old ones were super thin. I misplaced my micrometer but will look for it in the morning.
Royal Purple 5w20. likely a little thin but I've never had problems before.
The PO didn't understand maintenance. I had everything apart when I bought it a few years ago at 85k. Axle seals, pinion seals, RCV rebuilds, balljoints, brake lines, drives shaft balance and rebuild, s/c rebuild, Ripp long tubes and spark. The cooling system at 90k. Mashimoto radiator with contolled fan, oil cooler, transmission cooler. I must have missed the oil consumption when my son was driving it before he got his TJ.
S&J engines in Spokane, Wa seem reasonable and offer a decent warranty on a long block even with owner install. I'll be going by their shop in a couple of weeks to take a peek at production.
The hemi would take too long

 

I'm in Oregon, and have heard of S&J. Stay in touch, interested how it goes.

 

There is a sticky on JK Modified section that details a Hemi conversion and parts required. You may be able to talk with the member who did it to see what steps he went through. The 2007 ECU actually has an option to select a 4.7/5.7/6.1 Hemi engines (plus others). But I believe that was simply a non-variable cam timing engines so perhaps an earlier 5.7 will work as they are most common. Not sure though how the Jeep ECU would work with an 8 cyl. I did the Motech and LT conversion which still had some issues.