V8 Engine Swap into XJ

BeerDonor

BeerDonor

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Joined
Nov 18, 2007
Location
Blairsville, GA
Okay, I'm seriously considering swapping the motor out of my 84' XJ. I have a SBC 350 w/4 spd and TC. I'm not the greatest mechanic that walks the face of the earth, but I've done pretty well so far. Can anyone provide me with guidance or experience. I have read everything I can, on the net. Including Novak. Do I dare try?
 
What is the issue with your 4.0?

I have doen several SBC swaps into jeeps but not a xj. all of th XJ's I have had had more than enought power to break stuf and plenty of go.

I think your Issue will be that it is a uni body and does not have a real frame to weld mounts on.

What are you going to use this for?

you can rebuild the 4.0 and use a 4.2 crank to make a stroker motor if you want more power
 
Ridgerunner said:
What is the issue with your 4.0?
I have doen several SBC swaps into jeeps but not a xj. all of th XJ's I have had had more than enought power to break stuf and plenty of go.
I think your Issue will be that it is a uni body and does not have a real frame to weld mounts on.
What are you going to use this for?
you can rebuild the 4.0 and use a 4.2 crank to make a stroker motor if you want more power
Click to expand...

In 84' the 4.0 was not available. I have a 2.8L V6 (DAWG). After alot of research. a 4.o swap is not recommended into an 84'. In 87' they changed the firewall and header to accept the new 4.0. So, my delima.
 
350 swap is doable but not practical in your xj, look into doing a gm 3.1/3.4/3.8 swap, The are the same bellhousing bolt pattern. A 3.4 would be a nice swap especially if you did the fuel injection stuff also. If you are deadset on a v8 look at the caddilac 4.1/4.5/4.9 the have the same bellhousing as a 2.8 also.
 
I have been throwing this idea around for the last 2 months, I have an 88 XJ, with a completely stripped down under hood, it had a blow 4.0, after some careful reading and some measuring, and figureing $ wise, it is just not worth the trouble to try and swap a 350 sbc into my XJ

1. The xj's unibody, would have to be cut and patched to get the manifolds, much less a set of headers to clear, and if you gonna do this

you might as well do this

basically you would have to cut the unibody at the firewall and tube the front of the XJ out to make it work right, then reinforce the unibody all the way back adding some bracing as you go

check out advance adapters to get a price on there motor mounts and headers for this swap
 
alright this topic interests me also, I just got off the phone with advance adaters

they have bolt in motor mounts, they say no unibody cutting is required but they are $200

they also say that the only manifolds/headers that will work with no modification to the unibody, are the ones they sell for $300
 
guffey24 said:
alright this topic interests me also, I just got off the phone with advance adaters
they have bolt in motor mounts, they say no unibody cutting is required but they are $200
they also say that the only manifolds/headers that will work with no modification to the unibody, are the ones they sell for $300
Click to expand...

Okay guys, great input by all.

First....I agree that the 350 swap is very aggressive. That other options are available that would bolt right up. My issue with that is, the tranny that came in my model XJ (AX5) is not even useful as a paperweight. Much less an offroad tranny bolted to a higher torque motor. So I ruled out utilizing my existing tranny.

Second....The transfercase, while useable, is not the best option either. My XJ has a NP207 currently. So, with the decision I made on the tranny, I decided to do away with the tc also.

Third....I currently posses a SBC 350 w/4 spd tranny and transfer case. All bolted together and running.

That is what has led me to this point. I want to do the right thing. If the 350 and drivetrain is not the right option, then I will sell it, to obtain the right option.

Ideally, I would like to have a high torque V6 with a rugged automatic tranny and a NP231 tc.

Now, what's everyones opinion and guidance?
 
also know this, If you use the granny 4 speed, your gonna have to cut the dash out where the radio would go, to shift the tranny

think about the difference in the length of the ax5 compared to the sm465
 
working and throwing the idea of a 5.3 xj ...........I say do the 350 swap and have fun... it may be a headache but youll have somthing very different.
 
Back in about 90 or so, before XJ's were cool, I did a 350, th350 conversion in a early XJ, and It worked out fine. After 4 years of mud racing, and street racing, it started to take its toll on the unibody, so I would make that my first priority. There are plenty of ways to reinforce it now days. I say do a v-6 of some kind because you would have more room to work with in that shorter engine bay.
 
well i dont think a 350 is a bad swap but if your doing it for power well then its just not cost effective b/c of the work you would have to do to brace the unibody "which is possible". Here is a site you will want to look at
http://www.novak-adapt.com/knowledge/xj_swap.htm
Its all about what you want and how much you want to spend....I dont see how the 350 headers would interfere with the firewall any less than the 4.0l...Not to mention you can get all the parts from a Cherokee in the junk yard where with the 350 you will have to find a tranny that fits in the tunnel and new transfer case which with would put your front driveshaft on the wrong side....or get a 4.0l/aw4/np231/ front and rear driveshafts and no adapters. Adapters alone on a 350 coversion are going to run you somewhere in the neighborhood of $800 or more. And all thats no even thinking about axles....wow im out of breath
 
mileshigh said:
well i dont think a 350 is a bad swap but if your doing it for power well then its just not cost effective b/c of the work you would have to do to brace the unibody "which is possible". Here is a site you will want to look at
http://www.novak-adapt.com/knowledge/xj_swap.htm
Its all about what you want and how much you want to spend....I dont see how the 350 headers would interfere with the firewall any less than the 4.0l...Not to mention you can get all the parts from a Cherokee in the junk yard where with the 350 you will have to find a tranny that fits in the tunnel and new transfer case which with would put your front driveshaft on the wrong side....or get a 4.0l/aw4/np231/ front and rear driveshafts and no adapters. Adapters alone on a 350 coversion are going to run you somewhere in the neighborhood of $800 or more. And all thats no even thinking about axles....wow im out of breath
Click to expand...

I considered the 4.o swap, but Novak talked me out of it. They said that it would be twice as difficult as any other swap. The problem being, an 84" XJ will have to be heavily modified at the firewall and header to make a 4.o fit.

So, do we all think I should go with a 3.4L V6?
 
http://www.nc4x4.com/forums/showthread.php?t=49688

Id say that would make alot easier swap then a 350... give you more room in the engine bay, a tranny thatll fit in the tunnel, and a case the drops on the proper side... Also it wont kill your axles first time out...
 
why can't you do a 4.3 vortec CPI??? That would be a nice package for the XJ, maybe even a ford 4.0 like then run in the ranger/exploder...
 
yota? they make an adapter.
 
Im no chevy man but couldnt a 4.3v6 bolt up to your 350 drive train? that would give you power but not so much that you mangle your unibody and you would have a tough drivetrain to back it. plus you could make a little cash trading the 350 for a 4.3.
 
oops didnt read enough
 
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