AMC 401 to 700R4 to QT 2 to 4 wheel conversion

[Jevman]

Anyone built this specific AMC 401 or 360 to 700r4 to Quadra Track drive yet? Front CV driveshaft Clearance on pan? Changing to regular 1310 U Joint style for clearance? 4" lift and a way to make this work without wobble or having it in 2 wheel drive except when you need 4 wheel drive? I bought the adaptors without enough research and this project isn't built yet so brakes are on and looking for input please, be nice, I'm handicapped so my wife says!

[sonoraed]

who's adaptors did you buy did you buy? Advance, Novak etc

[Jevman]

Advanced Adaptors

[Jevman]

This is a link to a video on Youtube of an LS swap where they used the QT on the back of a 700r4, they couldn't use the CV style driveshaft because it runs into the pan, this setup doesn't seem to look good for anything but stock springs or maybe a 2" lift? I'm at 2000 RPM @ 60MPH right now with the gear change to 4.89 and 33.9 in tires. I'm not sure what the angle is with a 4" lift on it, jeep is torn apart and I'm not home for awhile. This will be a driver more than anything else so disconnecting the front drive isn't a problem at higher speeds, it would just be nice to have a solution of some kind.

https://www.youtube.com/watch?v=iij91sDyIZk,

[OldFarmTruck22]

Its more of a diameter issue than an angle issue with the CV joint. The Dana 44 1330 flange is needed at the transfer case front output.
I'm real interested in seeing the steps and parts you are using to adapt the 700r4 to the AMC engine and quadratrac transfer case. I want to do the same thing.
Thanks

[OldFarmTruck22]

You might want to get the opinion of some of these guys on whether it's a good idea to disconnect the front drive shaft and run the truck on the highway on an early Quadratrac. I'm thinking there's gonna be some opinions.

[Jevman]

At this time my QT transfer case has the Mile Marker 2 to 4 wheel conversion kit and lock outs, I bought the AMC engine to 700R4 from BJ's and the 700R4 to QT there also, Does anyone know the angle on the stock set up TH400 with stock springs and then with a 4" lift, the 700R4 with the adaptors is the same length as the TH400 so it bolts right in( Maybe a little reaming on the mount) but the CV joint on the front drive shaft is to big to clear the Trany pan. The Yoke is a 1310 10 spline from info I have, thats to change it to a regular U Joint drive shaft and getting rid of the CV

[OldFarmTruck22]

Why is the angle important?

[Jevman]

The more RPM the less angle you can put on u Joints, 5000 RPM is 3.2 degrees and 1500 RPM is 11.5 degrees

[OldFarmTruck22]

Would engine RPM be the same as the front driveshaft RPM when running down the road?

[Jevman]

Transfer case would be higher RPM than the engine I believe

[OldFarmTruck22]

A 34" tire at 60 mph is rotating 2652 RPM upon the road surface. If you factor in .75 overdrive transmission ratio ... the engine should be at 1989 rpm.
However, the wheels are being driven by a 4.89 to 1 gear set. I highly doubt that the front driveshaft is also rotating at 2652 or even 2000 rpm to produce a tire rotating at 2652 rpm.
Someone on here will correct me if I'm wrong.

[Jevman]

http://www.grimmjeeper.com/gears.html. Try this. Put all your numbers in and WALLA....I'm good with the numbers for what I'm doing, I'm just looking for the angle on the shaft at 4"s of lift or some kind of new shaft or what shaft would be the best for this set up and the down falls of the setup

[OldFarmTruck22]

Your front driveshaft RPM at 60 mph will be 542 rpm. Tire rpm at 60mph DIVIDED by front axle ratio.
Check me on this.

[Yeller]

drive shaft rpm is very simple.... it is the same as engine rpm in 3rd gear on a 700r4. So.... 3000 rpm is 64 miles per hour. Here's the hard data along with gear ratios. There will be driveline vibrations and probably some severe shaft chatter that will make you think the transfercase is trying to eat its way through the floor without CV (Double Cardan, if you prefer) and correct pinion angle on the front. Rear may be in the same boat, may not, but we are not discussing the rear at this point

[Jevman]

Set Up: 4" Skyjacker Lift, AMC 401, 330 to 400 HP, 700R4, QT 2 to 4 wheel kit with lockouts, 33.9 Tires, 4.89 gears, E-Locker in front, True Track in rear

The following chart lists the RPMs your engine will be turning while driving at a given speed.

Road RPMs at given speed in miles per hour
Gear
5mph, 35mph, 60mph
1. 742, 5191, 8899
2. 395, 2765, 4740
3. 242, 1696, 2908
4. 170, 1187, 2036

Driveshaft RPM, Maximum Operation
5000 RPM, 3.2 deg
4500 RPM, 3.7 deg
4000 RPM, 4.2 deg
3500 RPM, 5.0 deg
3000 RPM, 5.8 deg
2500 RPM, 7.0 deg
2000 RPM, 8.7 deg
1500 RPM, 11.5 deg

I guess what i am looking for is where the angle is on a stock TH400 front driveshaft stock springs (factory) for reference and then when changed out to a 4" lift, what the angle is then. Where it falls into the charts above for drivability, if it falls with in the 8.7 deg area if it where in 4 wheel I wouldn't have to change from 4 to 2 wheel if I go to town and do they make a CV joint style that is narrower to clear the pan?

[tgreese]

JMO - seems a little quixotic to stay with the AMC engine and Quadratrac if you want the 700R4. There is a NP241C that's passenger drop and - I presume - will bolt up to the GM transmission. Usual path, I think, is to buy a donor with an MPI SBC, modern overdrive automatic, and matching transfer case. Lots of these swaps have been done, but things are usually popular for a reason. The offset rear axle is the usual issue; the centered 6-lug D44 for a Wagoneer is pretty scarce now. I'd think you could go custom if you were willing to spend the money... maybe narrow a J10 axle?

Also, I had to search your old posts to find this is a WT Cherokee. It must be '73-79 since it's a Borg-Warner Quadratrac. It would be helpful to include your year, model and equipment in your signature file - this will appear with every post. I also suggest you add your general location to your stats.

[Jevman]

Thanks, what i'm doing is keeping this Cherokee W/T as original as I can, rebuilt Th400, QT, 360, stock springs and wheels stays with it numbers and all, all restored to new, I have a rebuilt 700R4 that bolts right in with no modifications except the adaptors, it's a 100% nut and bolt frame off restore, every component on this Rig will be new or restored, the wiring is getting replaced and all new Dakota Digital because these things were wired to there time and burnt up. AM/FM/CB radio and interior will be restored to as close as possible with sound deadening and insulation, it's also getting a new 401 for now. All these things I'm doing to it are easy to return it to all the original equipment in a blink of an eye without hacking it up, I have other Jeeps I can Hack up. I can drive this thing down the road at 90 MPH with the front drive disengaged all day long and if I'm on a trail it wont matter at that speed in 4x4 if it has a CV front driveshaft or not, I'm just looking for a way to engineer that problem out of it and it probably won't happen but then again? My Jeep, My Money! Thanks for the good info above though tgreese, I may use that on one of the the others! For the time being I'm just looking for the angles here because I'm not home and in the sand box, keeps me busy with any spare time there is.

[OldFarmTruck22]

I like the fact that you are keeping the AMC engine, BW 1339 transfer case and front and rear diffs. Many of us are looking to do the same thing. So we look to you to show us the way on this vital improvement. My 78 is reaching for another gear at 60 mph, and I have an old 700r4 trans in the shed I been thinking of rebuilding.
Tell me, what output shaft in the 700r4 do I need to mate to the BG 1339 case? How many spline, and do you remember if you needed to trim the shaft shorter to fit the adapter between the transfer case and transmission?
Thanks

[Jevman]

I bought the kit from BJ's, Advanced Adapters AMC to 700R4 and 700R4 to QT for $878.74 (two kits), fits perfectly in place they have told me, the 700R4 (shaft needs to be cut off about 1 1/4") and the spacing of the two adapters is the same as the TH400 alone, everyone just needs to know the double CV won't fit, regular 1310 driveshaft will, have to change out the Yoke on the transfercase to fit the new drive shaft at $90 (1310 10 spline), the other thing that's needed is the 2 to 4 wheel conversion from Mile Marker rebuilt $2215.00 or the kit for $540.00 with lockouts, mine had it when I bought it. Using the GrimmJeeper calculator and 33.9 tires, 4.89 gears it has a lower crawl speed than the original setup, 2036 RPM @ 60, 2545 RPM @ 75 and 3053 RPM @ 90, 3rd gear 2908 @ 60 mph pulling a 5000 pound load, 330 to 400 HP, 4" lift it will probably be limited to 40 to 50 mph in 4x4, don't know yet but will find out