Lumpskie's Swap Questions Thread!

[Lumpskie]

So, instead of tagging onto another thread to ask my questions, I thought I'd just start a new one.

Right now, I've got a decently clean Grand Wagoneer with 112k on the clock. The AMC 360 was rebuilt 2,000 miles ago and it runs well. That being said, I'd like to upgrade the drivetrain (and suspension as needed) to something more potent.


So, my goals for this rig are as follows:

1. Long term turn key reliablility - This rig will end up being my wife's daily driver.
2. Gas mileage - If I go through the cost of swapping another motor, I'd like to see 20mpg
3. Towing capacity - This wont be used very often, but is a justification (in my mind) for going through the effort. I'd love to be able to trailer my tacoma to Moab, over I-70 without issues.
4. "Creature comforts" - My wife drives a civic with Integra running gear. The car spins 4,000 rpm at 80mph, has basically solid engine mounts and has a loud exhaust tone but gets 33mpg on average. So, my wife can stand listening and feeling a motor if it nets her performance. That being said, I'd love to do interstate trips with this thing and don't want to go deaf/numb after an hour of driving.

All that being said, money is NOT a huge driver in this equation. I'd like to be frugal but I'm willing to save and wait to do this project right. Really, I'm open to any option on the best way to get to my goals, so if you guys have any suggestions (Fuel injection, gas engines, diesels or anything else) I'd love to hear them.

Thanks,

Justin

[will e]

Options:
1. Keep the 360. With some money you can get decent performance out of it. Port fuel injection will improve the tuning ability. A different cam would help. Swap in a OD transmission (requires expensive adapter plate). It will probably run you about $6000 or so depending on if you can find a deal on the transmission and if you can do the work yourself. You probably won't get 20mpg. You might on the highway if you stay at 55mph. A little less work than swaping in a newer engine.
2. Newer engine. Again the Vortec seems to be a popular swap. The conversion motor mounts are available. OD transmissions were standard. You will get modern fuel injection, intakes, head designs, etc. It's a little more complicated than the 360/OD improvements. Other things like exhaust, Radiator, cooling lines, power steering lines and A/C lines can all add to small 'gotchas'.

[Lumpskie]

^So, it sounds like, knowing my goals, you'd suggest going with a Vortec over a diesel. I guess that makes sense, given that I don't tow much. Other than ease of the swap, are there any advantages of going with a modern gas over a diesel? How many miles to people get out of the Vortecs before they need to start fixing a bunch of "little things". I'm doing my own research, but I'm so skeptical of internet posts and I'd love to hear some opinions I can trust.

[tndonor]

With my second FSJ Diesel conversion, I can say that the costs of the extras on both swaps was more than the drivetrain. Substantially more.

Long term reliabiliy is becoming less between the newer gas motors and Diesels. A Vortec or LS family motor will go 250K if taken care of, even more. Will a Diesel go longer, yes they can but the laws of diminishing returns has kicked in.

For fuel mileage, you can attain 20+ mpg with a 4B, even a 6.2/6.5. But here at altitude, forced induction (turbo) is about mandantory to tow anything over I70. You would also have to have an OD trans to get it. You can tune a Diesel for mileage by adjusting timing, etc but then you move peak torque curves, can get harder cold starts, more valvetrain noise, etc. The 4B I had in my J10 (p pumped 4B, NV4500 transmission, Dana 60s front and rear w 4.10s and 35" tires) I got 22 mpg on flat interstate. Had more than 10K in motor, trans, clutch, accessories, etc by the time it was done.

Tow capacity will again be determined by motor, trans, and axle gearing. If you gear 4.10 in the axle you will pull more and get less fuel economy. Gear at 3.54 and you will have great fuel mileage and poorer towing. It is really a case of pick one over the other as Diesels operate in such a relatively narrow RPM band for peak torque (which is where you want to operate the vehicle at as much as you can).

Im a Diesel nut but for what you are describing and the altitude you live in (and having a gas background) I would encourage an LS or Vortrec swap.

[Lumpskie]

Well, I'm not going to lie... I'm a little dissappointed that you guys are pushing for the diesel option. It looks like I should start looking into gas engines a bit more...

Hey Tndonor, if you're ever in the south denver area with your rig, I'd love to take a look, BTW.

Would that fact that I definately want a 5-speed transmission change much, as far as a build goes? I've done the floor cutting business before on my taco...

[tndonor]

I live off Lincoln betwwen Parker and Lone Tree..... shoot me a pm. Its not roadworthy again yet. Changing some things for Ouray

[will e]

Taco has an atlas?

[tndonor]

Or cutting brakes

[Lumpskie]

tndonor: I'll send you a pm. It will be good to meet a FSJ guy in person!

will e: The old taco has dual t-cases (stock '96 and a gear driven case from a hilux) with high/lo sticks for each but it basically acts like a poor man's Atlas setup. In fact my setup is geared pretty similar to yours (2.28, 2.56, 5.84) Here's a pic:

[Lumpskie]

What do you guys think of the 4bd1t engines? I found one listed in Grand Junction (4 hours away). Would one of those be worth a drive?

[Lumpskie]

Also, I've heard that the 4bd1-t engines vibrate less harshly than the 4bt. Does anyone have any insight on that?

[tndonor]

check out 4btswaps.com tons of info there on the 4bds

[Lumpskie]

^Thanks for the info. I'll log-in over there and ask 4bd specific questions. Hey tndonor, which Cummins are you running? How do you like it?

[Lumpskie]

Quick update:

I've really been researching the Isuzu 4BD1T engine lately. Does anyone on here have any experience or data to share on swapping one of those into a Wagoneer?

[carnuck]

What do you guys think of the 4bd1t engines? I found one listed in Grand Junction (4 hours away). Would one of those be worth a drive?

Try to get their version of the AW4 to go with it. Starter mounts different, etc than Jatco trans. Later motors were crappy but they had the awesome trans. Go figure!

[Mr. Goatman]

I am in the middle of a 4BD swap. It's not a lot different than a 4 BT. I think it is quieter and overall a better balanced engine. I am using custom mounts (patterned after the ones from Jeepin Pete) a 47RH transmission and an NP205 from a CTD unit. It also has D60 front and rear from 1st gen (Pre 94) Dodge CTD. I hope it is on the road late this summer (of course I've been saying that for a while) I have a build thread a few lines down with parts sources.

I do agree with the statement that the little incidentals will cost as much or more than the drive train. I love diesel and therefore never though about any of the gasser conversions. I do believe they would be cheaper and easier. I already have an 88 bought to put a 6.2/700R4/203 with a banks kit in for the wife's DD.- But that's for next year.

If I were to suggest a drivetrain for ease of parts and cost considerations it would be #1 a 6.2 GM (Yeah I know, booo, booo) Followed closely by a 6BT (12V cummins)

If you find a 4bd1-t and decide you don't want it, let me know. I'm looking for another one.

[Lumpskie]

Hi Mr. Goatman,

It looks like the seller for the 4BD1T wants to keep his motor now, so my swap profile is back up in the air. The more I investigate, the more it seems like that motor would be exactly what I'm looking for. Basically, the perfect daily driver/occasional hauler motor. Because I don't want to lift the jeep, I've been wary of the 6bt. Have you seen anyone that has installed a 6bt without lift?

[Mr. Goatman]

I have not paid much attention to the 6BT until recently. I had to BL 2 inches with the 4bd1 because it is sooooo tall. I know the 6.2 will prob. need a BL as well.

[Lumpskie]

^I didn't realize that you needed a body lift to fit the 4bd1. That's good to know.

[TrenchFoot]

I'd echo everything said here so far: An LS swap is the easiest path for your needs, provides comparable or better mileage to almost any diesel swap, and may be cheaper when all said and done. But it's not a diesel. If you're in this forum, you probably have your fuel screw turned up...

All that said, I'm going with a 6.2L and a Banks turbo kit. I think it's the best fitting diesel in a FSJ, weighs only slightly more than a AMC V8, returns great mileage, and should be one of the cheaper diesel options. For the average DD Wagoneer, the 6.2 looks like a great fit. For guys with heavy towing demands, huge tires and maybe rock crawling I understand the need for a 6BT.

The 6.2 has a poor reputation though. Low power and blocks that have a habit of cracking are common complaints. If you choose your donor carefully and throw on a turbo you can have a potent, efficient engine that fits without a lift, sheetmetal work or new axles. I chose a 599 block casting from a 93, the best casting GM made but there's other good years. And stick with "J-code" donors from a 3/4 or 1-ton instead of C-code from a 1/2-ton to eliminate the problems EGR introduces.

Regardless of whether your go LS or diesel, follow the advice you've probably read everywhere: buy the whole donor truck. I got just my engine and have been nickle and diming my way into a huge pile of expensive parts. I also wish I had just dropped the engine as-is instead of rebuilding it, I would have been done years ago.