Motor Conversion Choice

Intro: Marc
Grand Prairie, TX
Previous Vehicle 71 FJ40 8" lift 35" tires stock motor, trans, axels. Pretty fun but awful heavy. I would like to create a unique trail/cruising rig with this one.
I have used the search function and am currently working through the pages of excellent info..
Likes: Golf, Guitars, VW's, BMX,Mountain Bikes and last but not least anything that allows me to laugh with the kids Jordan 13, Joseph 8, and Jonius 2. I guess I should mention the woman who puts up with it all my Old Lady/Wife La'Shon

I have a few questions that I thought someone could help me with:
1) My Dauntless V-6 is locked up, it has been sitting for probably 10 yrs. The whole jeep was given to me. I have the opportunity to get a running complete 350. My question is would it be smarter to swap out the motor and tranny with a chevy tranny say a sm420 or other bolt up situation. Or keep the original tranny and purchase the conversion from Novak? I guess what I'm getting at is buying a Engine Conversion Kit or a Transfer case adapter kit.

What will I be doing with the rig?
Light wheeling, just having fun with the kiddos ie mud holes and trails.

Plans: Extended Wheel base 10-12", SOA 35" Supers , disc conversion

2) I have an idea in my head about making this a 4dr taking two tubs and cutting to make one. Anyone done this? Anyway this is just something that I can work on learn and have fun. Any help, comments, or suggestions would be greatly appreciated.


Thanks
Marc

 

If you're gonna run the 350 in it, I would go ahead and swap out the stock tranny and t-case. The sm420 with a 205 on it would probably be the simplest way to go to have a good setup. If you're gonna stretch the wheelbase on it, then you wont have to worry a whole lot about the length of any combo much, but the 350/420/205 is probably the easiest way to go. If you look around, if your area is the way mine is, you could probably find a sm420 with a 205 on it for less than what an adapter would cost you to use the stock setup. I would go ahead and put a hydraulic clutch set up on it too while your changing things. Altogether not too hard of a swap to do, and it would all give you a pretty good set up. My 79 CJ5 is sittin at around 98" right now, and I'm stretching it out more to try to get about 110" or so out of it. For it I'll be running a sbc with a th350 and a dana 300. I like the auto better for what I'll be doing with it, and the 205 isn't low enough to turn the tires that I'll be running, so I had to go with a regeared 300.

I've never tried to make a four door, but we've stretched wheelbases, rebuilt frames, and also cut the back portion of the tub off of them and moved it up behind the drivers seat on some of the rigs here, so I'm sure it can be done.

 

Welcome aboard btw!

 

How 'bout a Buick 350 instead of a Chevy? (Dist at the front)

 

Rebuild the Dauntless? I am not opposed to this. I see that Autozone has a total rebuild kit for $355. Do any of you guys have a suggestion on rebuilding the V6 ie Boring it out or keeping it mostly stock, different cam etc etc... ? I only started to go the 350 route because I have a running 350 sitting here. But I do agree it would be easier to just rebuild the V6, thats what I love about this site, when you start getting off track (my orginal goal was to just get it running) you guys will help get back to what the main goal is....

Let me ask another question, If I rebuild the Dauntless will I have a problem running 33's?
This will be running around town and trailing only. I really appreciate the quick responses.
thanks
marc

Sidenote: I was looking at the engine last night and noticed 2 mounting brackets on the front of the motor, 1 goes to the alternator, what is the other one for, it appears to go to the drivers side, but either this jeep is missing something (AC ha ha) or its just an extra bracket.

 

If you're just doing moderate wheeling the Dauntless is a pretty powerful engine. Stock parts aren't too bad to find, but they get pricey if you want gobs of power.

My dauntless had MASSIVE amounts of torque. You'd be amazed what that little engine would do. If the engine is rebuildable, I'd go that route. Even with the dauntless I'd keep the SM420 swap in mind, that's a great transmission to have in a jeep.

 

No problem running 33's depending on diff gearing. I can turn my 33" tires on dry pavement with my 231, but I have 5.38 gears. I wouldn't recommend turning them on pavement by the way, it takes it's toll on partsR). 4.27's would be good as would 4.88's. If you have 5.38's an Overdrive unit would be good for hiway driving. The Dauntless or a 231 are great V-6's with plenty of torque that keep the vehicle well balanced, very driveable, and generally if realistic and proper care don't overtax the drivetrain like a V-8. If it were me I'd go for a 231 which is a bolt in, or rebuild the 225. Nickmil

 

Well I guess first things first, I'll pull the motor this weekend and see where I'm at. I still have a lot to learn about these vehicles, so this weekend I will learn exactly what axels I have, trans, transfer etc.. I will try to get some pics up to so we can track this excursion.

Thanks
Marc

 

First thing I'd try to do is free the 225. Put some MMO (Marvel Mystery Oil) down the spark plugs, let it sit a few days, and try to turn the crank with a big cheater bar. If all else fails, you can tow it and try to bump the engine with the clutch to free it.

Re the 350/SM420/NP205 setup, won't a 205 be too wide for the CJ frame rails? I'd think a SM465/NP208 setup would be better, plus the 208 has a better low range. Does Chevy drop on the passenger side?

 

I tried the marvins, did'nt work. I have heard diesel will do it, but man the smell. I read on a post on here of people trying to pull it and release the clutch I guess I could try that this weekend. I've never rebuilt a motor, I actually talked my dad out of auto retirement and he's going to help with it. He's an old school racer from back in the late 70's but he seems pretty pumped about working on a motor again. We never really got to work on cars together so that should be cool. Anyway, I'll keep you guys posted and I'm sure I'll have additional questions once this thing gets rollin.
Thanks
Marc

 

OK, I have been looking at these VIN numbers trying to figure out what was on my cj5 from the factory. Like what axels were on it, how many different options are there for a 71? What different trans and transfer cases were available? I have searched and just cant seem to find it tonight.
Thanks
Marc

 

The VIN won't tell you much in 1971. Maybe engine? Look at the VIN document.

Axles: closed knuckle Dana 27 front, flanged offset Dana 44 rear. Axle ratios: 3.73 (std) or 4.88 (opt). Look at the tag on the axles. Rear TracLock LSD optional. Look for a tag on the axle.

Only 1 transfer case, the Dana 18.

Options? IIRC HD springs, HD shocks, HD electrical (battery & alt), rear LSD, axle ratio, HD cooling (radiator), 4-speed transmission (very rare), rear seat, passenger sear, 40-60 split front seat, a couple of sizes of tires, gauge package? (amps/OP), draw bar... probably more - that's allI can think of now.

 

Yeah, I read the VIN document, and thats what I concluded. I thought I might be reading it wrong or the second set of numbers would have told me more.

Thanks for all the info

Marc



I lost my other project tonight, I will probably be down for a couple of days, she was with me a long time. But hey, I can now park a car that runs in my garage, well I mean my wife will.