Drivetrain swap?

Drivetrain swap?

JR74CJ5

Missing-Presumed Wheeling
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Plumas Lake, CA, USA
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1974 CJ5 ~ Fresh built AMC 360 - SM420 - D20 - D30F with upgraded 30 spline shafts and knuckles & D44R - 4.27 Gears - ARB Lockers F/R - All chrome molly axles - on 33's - YJ 4" Lift Spring Conversion
Alright everyone I have (long story short) had a Chevy 350 very newly rebuilt fall into my lap. (Not literally or I'd be at the hospital :cool:)

I've inspected the inside down to lifters crank and cam, and everything looks great.

SO... What should i do? I currently have a tired old AMC 304 . It's still running great, so there is no hurry, thus money can be saved up to not be a "factor" Again the AMC 304 has no problems... yet... I just have been seeing how hard it is getting to find AMC V8 parts & Upgrades as of late...

So I have the motor.

Right now I have a T-15 that desperately need rebuild (or now replacement with ? ~ looking around i see SM420 / SM465 and the expensive option nv4500/Atlas) it's popping out of gear and grinding through 1st and 2nd... and a Dana 20 I was planning a twin stick for (but again not done yet, and needs going through as well...)

So if I do the motor swap what should i run? I realize this is a large leap, with many conversions / adapters that will nickle and dime me, including drive shafts etc. I'm ready for that... :bang:

What do you guys think?

Transmission : I want a strong 4 speed with a granny low. I want it to take abuse. (axles are another topic) But all options and opinions are welcome!

Transfer Case : Again strong for abuse, easily adaptable for twin stick, and maybe the 4:1 gearing options that Dana 20 can do (have been reading up on beefing that thing up for initial plans)...

Recommendations? I'll appreciate any advice / suggestions you all have!

Even the "NOOOO don't do it!" guy's...

This, when ready, will be done during a full tear down to frame and re build, of course covered in a build thread. :cool:

:booze: ~ JR
 
As you said there's a lot more cheep chevy parts that amc parts out there.
But doing the swap will take some fab work and lots of nickels and dimes.
That being said I like my 350.
Advance adapters or Novac both have lots of info on the swap.
 
Alright guys, So I've been doing more searching and reading (I swear i feel like a "electronic librarian" these days... Click read click read :bang: )

Found a peviouse post from CJim7:

"As far as tranys, the NP435 is probably the best offroad choice as far as a manual tranny goes. Granny low, and tough as hell. the SM465 is a good and common tranny, but extremelly heavy. I reiterate heavy. the 435 is easy enough to find also, they are plentifull. Along with that tranny, one of the best xfercases ever built was common-place behind it. The NP205 is a gear driven, cast iron case that is about as strong as it gets. Better then the Dana 300 for that reason, and also for the fact you wont need an adapter. These are also plentiful and relatively cheap.

Read more: http://www.jeep-cj.com/forums/f2/chevy305-700r4tran-7822/#ixzz1IgvXrEZy "

So this combo: Chevy 350 / NP435 / NP250 would all bolt up together inline no adapters required and be "great componants"?

I can (only searched briefly so far) get the tranny and Transfer Case for $1,376.00 (plus core shipments ov course...) Which is not terrable... All new reman. and free shipping to my door...

I realize i can probably find better deals than these prices from: High Performance Aftermarket Auto Parts - AutoPartsDealer.com Just looking at the feasibility of buying newly reman'ed, and it doesn't look bad at all.

From there i'd just need to do the adaption into the rig right?

Anyone running this combo, or even some of the pieces have any feedback?
(Thanks by the way Old Dog! :chug: )

~ JR
 
The np435/205 combination is strong as hell, plus a 205 can be
Twin sticked, and a np203 can be bolted to it for a doubler setup. Which equals some seriously low gearing, when in granny gear. You can't find a more common, reliable, cheap, and easy to work on motor than a sbc, I mean they sell whole master rebuild kits for $200, so all in all I think you have made a great choice.

DROOOID2
 
Found a sweet deal on np465 / np205 together in town (says working order) for $300.00!

But (as mentioned above) CJim7 specifically noted they (NP465) are heavy... I guess even if for just the Transfer Case 300.00 wouldn't be bad if i knew it worked... Why can't the world just be full of honest people lol

So question is just how heavy are they, and what drawbacks does that entail?

(And thanks Cheepjeep85! Think I'm still sticking with that combo, just fishing around the web searching...)

~ JR:chug:
 
The weight of the components in your application, I think is trivial, unless your concerned about micro fuel mileage, in this case, thicker and heavier is better

One massive caveat with the 435 or the 465, they are both dinosaur trannies, in that they dont synch quick and really have an old school shift, long, slow, and sloppy. If you've driven any thing built in the last 20 years, you find the shifting is clean, clear, quick and firm (and nothing like what your headed for).

Ive bought new trucks over the years, and well lots of used trucks too, Ive had a 435 new in an 87 F250, I hated it from day 1, in 88 I bought another new ford, with the ZF5 speed, day and night difference (not taking into account the Overdrive ). I also used to drive a wrecker that had the SM465. I think if you do some research you will find the 435 and 465 went into production a loooong time ago. Yes, very stout and strong, but shifting characteristics suck ****. Just a note to let you know.

I personally don't care for sticks in general, (still have on in my Cherokee though), but If I was dropping a chevy in my cj and was going manual, Id be buying a NV4500. Something to consider.. they came in chevys, but not with a 205 behind them, you would need an adapter for your Transfer Case .

But by all means, go with the 435 or 465, if you dont like the way it shifts, you still have options,...just food for thought...(assuming youve not driven a truck with a 435-465).
 
Deffinatley great info & Appriciated! :chug:

I currently own a 1979 Ford F-AMC 150 with a manual 4 speed. Not sure (now that i think of it :confused:) what Transmission is in there. But it is exactly as you describe slow, long and sloppy.

I really don't forsee myself wanting to race this jeep around much. Yeah it would be nice to smoke a few of those little loud "sounds-like-my-weedeater/lawnmower" racers :driving:, but I'm very used to the slow and delicate shifting.

Although as i said before the advise is much appriciated, i hadn't thought of that much. I really want this jeep to be reliable enough to drive to the Rubicon, pismo beach, sand mountain etc around me and play HARD, and know I'll be still driving it home. Strength and perfomance Off road are my main goals.

Thanks Busted!:notworthy:
~ JR
 
Your ford should have a T-18 , also a good swap into a cj can be adapted to the 350 and the Dana 20 . Weight really won't be an issue with a sbc, I'll bet you are planning 1/2 ton or 1 ton axles with big tires, those will out weigh any tranny you can possibly use anyway.

DROOOID2
 
Well, thanks again all!

I decided to let the sbc 350 pass by me. I had lined up the NP465/NP205 for $300.00 from craigs list, started really going for it, then decided I've never even seen what my AMC 304 is capable of yet. The tranny (T-15 ) needs a rebuild and gears were all chewed in front diff etc. Decided to fix up everything as is and see what it can do before changing out everything...

Thanks again though for all the replies and info... :notworthy:

It will definitely be useful if I do plan this in the future, or maybe for some others who will see this thread.

~ JR :chug:
 
If your AMC 304 is in "good" running condition, as in compression, oil pressure, and ignition, throw a set of header on it, it will really wake it up. If you cam and timing chain are in good condition, it will make enough power to put a smile on your face. When I played with AMC 8s, I also changed out the dristributors with a better curve. There are several threads on that subject here on the site.

If you like what the headers did, then thow a offy 4 barrel intake and a a holley carb on it to top it off.

Need to do the headers first. If you do a 4 barrel first, it will typically run a little smoother and cooler, due to the richer fuel ratio, but will do little in the way of increasing power. The exhaust on a stock jeep is far more restrictive than the intake side. I learned that over many years and many jeeps.

Good luck on the AMC 304 , also keep an eye on your oil pressure after you change the oil, Ive seen some loose oil pressure after an oil change, they loose their prime sometimes, even if you top the filter off with new oil.
 
Yeah i have headers already on them, although with some issue... ( http://www.jeep-cj.com/forums/f2/one-header-angles-down-8228/ )

Did just change oil a month ago approx, been keeping a good eye on pressure as its one of the only gauges that works lol

Haven't dipped into the new carb or HEI yet. Although ive seen a lot of posts on both, and the HEI gear "issue" as well...

I was mainly thinking of switching to that sbc because it dropped in my lap for dirt cheap, was in great condition and parts to upgrade are easier to find and cheaper to buy.

But going to keep it stock (motor type wise) for a while.

Thanks Busted...
~ JR:chug:
 
Yeah i have headers already on them, although with some issue... ( http://www.jeep-cj.com/forums/f2/one-header-angles-down-8228/ )

Did just change oil a month ago approx, been keeping a good eye on pressure as its one of the only gauges that works lol

Haven't dipped into the new carb or HEI yet. Although ive seen a lot of posts on both, and the HEI gear "issue" as well...

I was mainly thinking of switching to that sbc because it dropped in my lap for dirt cheap, was in great condition and parts to upgrade are easier to find and cheaper to buy.

But going to keep it stock (motor type wise) for a while.

Thanks Busted...
~ JR:chug:

Your welcome, Im pretty hip on chevys, but if I came across a CJ with a solid AMC 8 in it, Id typically not change it out, AMC 258 i6 / 4.2l or a GM 151 is a different story. The AMC engines are not as robust and forgiving as a chevy, but will make damn near hp to CID if you do an apple to apple build, aw, I might even put my money on some of the early AMC 8s that had bigger valves. I just got tired of the finicky oiling system of those motors.

I took the 71 360 out of my current 83 CJ because it was just tired, leaking like a sive, and needed rebuilding. My CJ is getting a new drivetrian, Ive already bought a couple copies of everything, I just can make up my mind which to run with, but all three are chevy ( TBI, TPI, or LSx).

That bent header, it didnt come that way, gravity and heat cycles pulled it down, and the reason the right side didnt do it, is probably only radom in the way the tubes are welded together, the fenderwell header mufflers need to be supported in the back. Ive bought those new and bougth Cjs with them and Ive never seen one "bent" like that. But I do know that will happen with any header that has a muffler on the end of it without support, its waaaay to much leverage on it, then put the heat cycle to it...
 
I just got tired of the finicky oiling system of those motors.

I've heard a lot of mention of this "oiling problem" can you point me twards some older posts threads or info to read up on exactly what that issue is? Feel like i'm missing some important info :confused:

That bent header, it didnt come that way, gravity and heat cycles pulled it down, and the reason the right side didnt do it, is probably only radom in the way the tubes are welded together, the fenderwell header mufflers need to be supported in the back. Ive bought those new and bougth Cjs with them and Ive never seen one "bent" like that. But I do know that will happen with any header that has a muffler on the end of it without support, its waaaay to much leverage on it, then put the heat cycle to it...

Headers that came with the Jeep from PO did this same thing, Headers i show pictured came out of the box (I bought and installed from Summit myself) that way before ever starting the motor after install... The only reason i (still) haven't braced them is i have been thinking of heating and jacking it back up, or cutting and re-welding first.

Those pics are from just after installing, see the paint hasn't melted off yet... lol But yes i do need to brace it before it gets even worse... Am planning to (for a while) see if i can get it bent back up and then brace, after they get beat to :censored: on a bunch of rocks from Rubicon, I may go with inside the fender well headers or shorty's

But they seriously did come this way. Summit offered to replace, but i thought it was something wrong with my rig seeing as the old set did same exact thing...

:chug:
 
I for one am glad you came to your senses.:D
 
I've heard a lot of mention of this "oiling problem" can you point me twards some older posts threads or info to read up on exactly what that issue is? Feel like i'm missing some important info :confused:



Headers that came with the Jeep from PO did this same thing, Headers i show pictured came out of the box (I bought and installed from Summit myself) that way before ever starting the motor after install... The only reason i (still) haven't braced them is i have been thinking of heating and jacking it back up, or cutting and re-welding first.

Those pics are from just after installing, see the paint hasn't melted off yet... lol But yes i do need to brace it before it gets even worse... Am planning to (for a while) see if i can get it bent back up and then brace, after they get beat to :censored: on a bunch of rocks from Rubicon, I may go with inside the fender well headers or shorty's

But they seriously did come this way. Summit offered to replace, but i thought it was something wrong with my rig seeing as the old set did same exact thing...

:chug:


Ok, if thats the case, Id call it BIZARRE ! Absolutely Bizarre. Ive been driving and playing with Jeeps since 1983..as well two good friends have, I seen ALLOT of jeeps but aint never seen that out of the box... no explanation...

Not knowing how they actually mass produce headers, I cant even guess how that could happen,,,...and its also odd that no one here knows why either... Im going to run this past the only person I know that knows more than me, hes go over 50+ jeeps on his farm,,..and he keeps track of odd stuff like this..

And as far as the oiling problem, Ive only been on the site for a couple months, I have not seen any threads on it, but in a nut shell, youve got an aluminum front cover, with steel gears, and cover is on the front, sump in the rear of the motor. That all adds up to problems with higher mileage motors or ones that didnt see good service (oil changes). As the "pump" wears, it can loose its prime when you change the oil. Thus starting up dry and running dry until you turn it off and realize its dry. The rockers also seem to wear faster than youd like and as you loose oil pressure at the pump, less oil makes it to the heads, more wear,... and the cycle continues on..
 
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thats interesting, thats very interesting.:cool:




And as far as the oiling problem, Ive only been on the site for a couple months, I have not seen any threads on it, but in a nut shell, youve got an aluminum front cover, with steel gears, and cover is on the front, sump in the rear of the motor. That all adds up to problems with higher mileage motors or ones that didnt see good service (oil changes). As the "pump" wears, it can loose its prime when you change the oil. Thus starting up dry and running dry until you turn it off and realize its dry. The rockers also seem to wear faster than youd like and as you loose oil pressure at the pump, less oil makes it to the heads, more wear,... and the cycle continues on..[/QUOTE]
 
Bulltear sells something called a mid plate that gets sandwiched between the oil pump alum. cover. It's made of steel to fix the oil pump problem due to the oil pump gears wearing into the stock Alum. pump cover. The other problem is that the oil travels from the front of the motor to the back and some problems can arise to oil starvation of the rear main bearing. You can find a fix for that too if you research it enough.

I just(today) passed on a LT1 with 50,000 miles, truck avenger carb,edelbrock intake,gear drive timing, 4 bolt main engine. Figured out that it would cost me over $1,400. to adapt to what I have and then who knows how much to upgrade axels, Transmission and drivelines.

For all you AMC 304 owners that want to put a holly truck avenger carb. on go with the 670cfm model. Called Holly tech line yesterday about jetting and power valve advice and was told my 470cfm carb was only recommended for 4 and 6 cylinder engines and was not made for street use, rock crawling only. WTF
 
Great info! Thanks all.

I also fixed that header problem today.
Heated and bent it, used some braces and secured them

Going to post se pics back on the original thread

Busted, there was one other guy on here that had the same issue with the header... I think he replied on that original thread. But yeah that was one of the only thing I hadn't found a solution or info for/ about here. I ended up torching the collector/ muffler side while jacking up rear tip. Rippled slightly on the top but came out sweet! Only problem is will still have to re- rig each muffler. Headers not really " fixed" u know? But it looks better at least!


~ Jr
 

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