• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

350 in an XJ w/ Tranny from a 4.3?

B

BIG NASTY

NAXJA Forum User
Location
Cedartown, GA
I've been offered a 350 for my XJ and was told that it would work with a tranny from a 4.3 and then bolt into the XJ. Any info ????
 
Those 4.3 v-6s are certainly nowhere near v-8s. They have no power whatsoever!!!!! My buddy has a wrangler with one swapped in and with 4.56 gears on 35" tires. It sucks on acceleration and torque and everything. My 4.0 will blow it out of the water. Sorry to stray from the thread but to contribute, don't do a 350 as it will be more money than you could expect, keep the 4.0---Kyle
 
trannys from 4.3s WILL bolt up to 5.7s (350s). I know this for a fact as my best friend swapped a 700r4 from a 4.3 compact Blazer into his fullsize Blazer with a 350.

just do a stroker on your 4.0, do a little searching, there is TONS of info out there on it
 
offroadman83 said:
Sorry to stray from the thread but to contribute, don't do a 350 as it will be more money than you could expect, keep the 4.0---Kyle
Click to expand...


jesus i dont know if you could be more wrong. the 350s are not hard or take alot of money to swap in. if you can do a little bit of fab skills or you know someone who can you can custom make you motor mounts, tranny adapters(if you are really skilled, you just might be able to. if not AA's are not that much), and then same thing w/ the tc adapter. then just buy a set of weld together headers and make sure to weld them the way you need.
 
700R4s have a hard time holding up to the tire-shredding power of the 4.3L, let alone having two more cylinders trying to blow it apart.

stroked 4.0L + aw4 auto = good RELAIBLE drivetrain.

Owl's right, and he oughta know, his XJ has a built small block in it. How many problems have you had keepin trannies together? Tell him what he's gettin into.
 
FWIW, the trannies are interchangeable. I believe there is a difference in torque convertors between the two motors. I've got a 4.3 in my MJ and I'm running a 700R4 out of a V-8 van right now. No problems so far.

As far as reliability issues, the early 700R4's had some internal problems that lowered their life and gave them a bad rep. But from about '88 to the time when they were switched to computer control, the durability has steadily improved. With a few upgrades, a 700R4 should easily take around 400 hp, 400 lb-ft.

Brent
 
Last edited:
With the right torque converter between them the tranny from the 4.3 will fit the 350. Built right the 700R4 is good for up to 700HP according to Art Carr. I had one rebuilt by his shop about 9-10 years ago and it wasn't a bad price then. Basically ya gotta get rid of the stock overdrive crap. The tranny burns up from the massive amount of heat built up during the flip back and forth between OD and drive.

Sarge
 
The 700R4 has dozens of valve body schemes and almost as many wiring configurations. Amazing how many times I´ve opened one up and found the wiring, did not match any, out of the FSM. Possible problems. Different pivot cam lengths for the CV valve and all sorts of differences.
The late model 350´s have a very close tolerance between the water jacket and the cylinder wall. It´s not uncommon for high RPM´s and/or lean burn and detonation, to pop the head gasket.
Guess I´m prejudiced, Maybe somebody has built a bullet proof 700R4, but like flame retardent underwear, I´m not gonna put it on, fire it up and try it out. Been burnt to many times.
 
You must log in or register to reply here.

Similar threads

D
Specific Moab Wheel On XJ
Replies
16
Views
235
DirtySouthXJ
D
chris420
Dana 50
Replies
7
Views
593
Rockwood
R
F
99 XJ V8 Swapped, now door's will unlock but won't lock
Replies
3
Views
164
FreeRoller16
F
R
Which steering box brace? Bearing or not?
Replies
7
Views
380
75SV1
7
W
Newbie with an XJ
Replies
9
Views
213
Wander Motor
W
Back
Top