86 CJ7 with 92 YJ head and fuel injection?

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snd00nz

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So I picked up an 86 CJ7 stretched and linked crawler with a 258ci engine that has been converted to the 92 YJ fuel injection setup. Looking at possible mods and/or upgrades and curious the compatibility or cross reference type items that work on both platforms. First maybe a header and low restriction exhaust system, are the headers the same from the stock year to the upgrade? I think they are different but not sure? Maybe any other suggestions for a strong and dependable setup?

Thanks
 
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If they did a full pulley swap and it is running a serpentine, everything for the 92 YJ should fit right on.
 
So I guess that brings up another question. What all did they need to swap to make this conversion? What would have been the minimum? Is the head swapped or just intake and fuel system?


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snd00nz said:
So I guess that brings up another question. What all did they need to swap to make this conversion? What would have been the minimum? Is the head swapped or just intake and fuel system?


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I have seen Fuel injection conversions. It is more common than the full head swap. Can you post a picture of the top of the engine? That will give it away.
 
Blade said:
I have seen Fuel injection conversions. It is more common than the full head swap. Can you post a picture of the top of the engine? That will give it away.
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I'll try and get a pic posted up tonight when I get home. I know it has the YJ computer and fuel system. Just not sure about the head.

Thanks


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Blade said:
I have seen Fuel injection conversions. It is more common than the full head swap. Can you post a picture of the top of the engine? That will give it away.
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+1 on the full head swap.

I did this on my 85 CJ7 with a head off of an 93 XJ. The swap needs the CPU the engine wiring harness and a few sensors. Mine used all the 4.2 accessories and not a serpentine. Although the swap was done in 99 and the details are somewhat fuzzy.

If I remember correctly I went with the full head swap because it flowed better than using the Mopar EFI swap that was just the intake, and it was cheaper.
 
bigcale said:
+1 on the full head swap.

I did this on my 85 CJ7 with a head off of an 93 XJ. The swap needs the CPU the engine wiring harness and a few sensors. Mine used all the 4.2 accessories and not a serpentine. Although the swap was done in 99 and the details are somewhat fuzzy.

If I remember correctly I went with the full head swap because it flowed better than using the Mopar EFI swap that was just the intake, and it was cheaper.
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Cool, hopefully a pic tonight will help clear it up. Thx again for the help.


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Okay here's a pic. She's not the purdiest, but should get the point across. Lol. IMG_5290.jpg


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One more, are these engines solid or hydraulic lifters for the cam? Need to adjust the valve lash. Thx


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bigcale said:
+1 on the full head swap.

I did this on my 85 CJ7 with a head off of an 93 XJ. The swap needs the CPU the engine wiring harness and a few sensors. Mine used all the 4.2 accessories and not a serpentine. Although the swap was done in 99 and the details are somewhat fuzzy.

If I remember correctly I went with the full head swap because it flowed better than using the Mopar EFI swap that was just the intake, and it was cheaper.
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Got a pic posted. Any thoughts? Thx


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snd00nz said:
Okay here's a pic. She's not the purdiest, but should get the point across. Lol. View attachment 243298


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Tough to tell by the pic but it looks like a 4.0 head. The 4.2 came with a stamped valve cover not a cast one, although there were several aftermarket aluminium ones available.
CJ
984cbcea6c8daa3452505a802a708f8f.jpg
YJ
92_jeep_wranger_dv_13.jpg

I don't have any pics of my old CJ, what I had was lost a long time ago, the Jeep was sold in 2002.

As far as your original post, I would stay away from headers on the straight 6, they tend to crack. I seem to remember some of the 4.0s coming with a shorty header from the factory, not sure what Jeeps it was in though. If it is running a v belt then it is most likely CJ stuff on the front.

I would leave it alone unless you NEED more power. If I remember correctly the best options back then were a chip and a throttle body spacer, they would give decent gains and other than having to run premium gas they were reliable.
 
bigcale said:
Tough to tell by the pic but it looks like a 4.0 head. The 4.2 came with a stamped valve cover not a cast one, although there were several aftermarket aluminium ones available.
CJ
View attachment 245426
YJ
View attachment 245427

I don't have any pics of my old CJ, what I had was lost a long time ago, the Jeep was sold in 2002.

As far as your original post, I would stay away from headers on the straight 6, they tend to crack. I seem to remember some of the 4.0s coming with a shorty header from the factory, not sure what Jeeps it was in though. If it is running a v belt then it is most likely CJ stuff on the front.

I would leave it alone unless you NEED more power. If I remember correctly the best options back then were a chip and a throttle body spacer, they would give decent gains and other than having to run premium gas they were reliable.
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Very good. Thank you. Any direction on chip? Not looking for huge gains just a little better for when on road not crawling.

Thanks


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snd00nz said:
Very good. Thank you. Any direction on chip? Not looking for huge gains just a little better for when on road not crawling.

Thanks

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Jet makes one for the 92 YJ still. I think superchips used to, but I don't see it on their site, it might be worth asking them.
 
I've been looking heavily into this swap. If it got the head then you need to go with a 4.0 exhaust manifold. The factory ones cracked so aftermarket is a better route to go. As far as head identification you can go bu casting number. I think 7120 and 0331 were a couple of the ones from that vintage. The number is above the #4 exhaust port cast into the metal.
 
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