TJ engine swap

TJ engine (and or Transmission/Transfer Case) swap

After five years of living with an underpowered 4 cylinder jeep, I think it is time for an engine swap.

The Dream Plan:
Right now I am looking at the Advance Adapters bolt in Chevy V8 mounts, a Chevy V8, NV4500 transmission (although there is a bellhousing adapter for my AX5 :) ), and keeping my NP231 transfer case but adding a 23 spline input. I will also need a new rear axle.

Could get everything from manual-transmissioned 4x4 Dodge Dakota, Durango or 1500-3500 truck with a 5.2L or a 5.9L V-8.

If I don't get a new engine before the AX5 gives out, I will need todo a transmission swap first.

AX-5 Gears 1st 2nd 3rd 4th 5th Rev
3.93 2.33 1.45 1.00 0.85 4.74

Maybe use a lower cost 4speed transmission
SM420 ~$100 (parts hard to find) Can use common GM bellhousings to mate with GM V8.
Standard GM car (4 11/16") Bellhousing Bore

Gears 1st 2nd 3rd 4th 5th Rev
7.05 3.58 1.71 1.00 None 7.05

To use with current 2.5L:
Can use a S-10 (blazer or pick up) or camero/firebird bellhousing for a GM 2.8L
Mount CPS on bellhousing
Gear reduction starter (like mean green) to clear bellhousing
Novak's SM420/SM465 to 2.5L kit $635 (will need new starter $250)
Novak's SM420 to NP231 kit $495

SM465 ~$100 uses weird bellhousing
Use a SM465 bellhousing to GM V8.
5 1/8" Bellhousing Bore. GM Trucks 68-89

To use with current 2.5L: www.novak-adapt.com says could take 2.8L bellhousing, and "The bore must be opened up to 5" and the retainer turned down to 5" as a .005" to .008" slip fit."
Novak's SM420/SM465 to 2.5L kit $635 (will need new starter $250)
Novak's SM465 to NP231 kit $489

Ford T18 a Ford T18/NP208 (like from F150) has a driver side drop

NP345
Use a modified AA NV4500 adapter plate.


Transmissions with overdrives:
AX15 or NV3550
Good for street use, stock gearing with overdrive. Above transmissions are really only 3 speed on street with no overdrive.

AX15 Gears 1st 2nd 3rd 4th 5th Rev

3.83 2.33 1.44 1.00 0.79 4.22

NV3550 Gears 1st 2nd 3rd 4th 5th Rev
4.01 2.32 1.40 1.00 0.75 ??

AX15 used $850 JeepsAreUs.com
NV3550 new is $1,595 from Advance Adapters
To use with a 318 V8 or 3.9L V-6:
Bellhousing from Dodge Truck with a 3.9L V-6 and AX-15

To use with 4 Cylinder:
Bellhousing (96-98 4 cyl Dodge Dakota)
Pilot Bushing (AA conversion pilot for nv4500)
Clutch Disk (Napa RCF4198, 1984 Chevy Camero with a 4 Cylinder and 4 Speed Trans)
"Both the AX5 and AX15 use the same release bearing and fork as the NV3500, so your stock slave cylinder will bolt in place on the Dodge bellhousing. We also used an Advance Adapters stainless steel braided hydraulic slave cylinder hose (PN 716130H and two PN 716130TJ) to replace the factory plastic unit."
From www.jpmagazine.com

NV4500
NV4500 Gears 1st 2nd 3rd 4th 5th Rev
5.61 3.04 1.67 1.00 0.75 5.61

NV4500 new 23 spline is $2,180 from Advance Adapters
NV4500 conversion kit for 4 cylinder TJ $2,899 from Quadratec

Chevy small block V8