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Help needed for intake swap!!!

Old_crow1

NAXJA Forum User
Location
Dearborn heights
I'll apologize now if I am posting it eye wrong forum guys. I have a 98 xj and had to replace my exhaust manifold.. go figure lol in the process of being manly and a bit rushed... I cracked my intake due to it not sitting flush. After about an hour of cursing at the sky I purchased a used manifold.. my question is this. I am coming from the "log" style intake to the "horseshoe" design intake. Is there any difference in bolt size that would inhibit the use of my existing bolts? Hoe am I to rewire and set this up as the log style has a different plug and play layout. I am not a mechanic, just a guy that loves his jeep and wanted to tackle this myself because money is tight. I've searched the internet and to no avail. Perhaps even if you had pictures with a write up? I've found some but none that involve a log to horseshoe setup. Thank you guys for your tine. Any info is greatly appreciated. Stranded till then.
 
Get the right parts, thatll be the quickest and cheapest way back on the road.
Just swapping the intake manifold wont get you any more power.
 
What other parts are required? Do I need any other parts in addition to the existing hoses and other connections? The intake layout appears different. The guy claimed it was from a 98 Cherokee and I just smiled and said let's hope it gets me running.
 
I havent gone from a 98->99+, but when i went 92->99+, there were numerous small and medium sized hurdles to complicate things... many of these things wont apply to your 98... but some may...

Id get a pre-99 manifold.
 
OP.

The "Log" style is 84-98. The "Horse-shoe" style is 99-01.

Buy an intake/exhaust manifold gasket for a 98 cherokee and bolt that intake manifold on. It will swap right on without any problems.

After that unbolt your throttle body from your old intake and bolt it onto the new intake. Now you can plug everything in. There's one plug you'll have to extend. Cut the wires, splice in more wire, re-connect. Someone is going to chime in saying blah blah blah doing that will change the resistance and the computer will think the mixture is different and you'll loose 0.0243 MPG and blah blah blah. I've done it, i'm still alive.

Other than that you might need to extend a few vacuum lines but that's easy.
 
Thanks man. Straight and to the point description. Any recommendations on things to replace while I'm in no man's land?

Ha, depends on what you're doing.

Take a good look at your exhaust manifold. Right at the crotch to be specific. Right where the two pipes connect to one they tend to crack right in the middle from your motor mounts wearing out.

The newer style intake should yield you about ~15 horsepower more than the other style.
 
I've heard this style will give a gain in HP. Whether that is true or not is for the gear heads to determine. I just bought what was available. I picked it up for 75. I love my jeep. Just want it back on the road as she's my daily driver
 
It was cracked right down the collector. No noxious fumes but definitely loud on initial start up. Tons of carbon build up and wondering if I should get new injectors
 
Clean out and chamfer the dowel pin holes on the intake

New injectors are probably not necessary, but new injector O-rings are a good idea. Lube them well when you install the injectors.
 
I just changed my intake and exhaust manifold on my XJ and it was an easy task. If you do change the between XK years there is a difference between the 98 and 99 years and a few items will have to be re-arranged. There is a sensor that attaches to the intake and some XK drivers cut and splice the wires. Which is OK, but the easy way is to just relocate the sensor to the aft side of the intake.

As always make sure your gasket matting surfaces are good and clean and a new set for bolts would be a good plan.

I have a few pictures for you but it look like I can't post them.

Have Fun
Viper
 
I've heard this style will give a gain in HP. Whether that is true or not is for the gear heads to determine. I just bought what was available. I picked it up for 75. I love my jeep. Just want it back on the road as she's my daily driver

I've seen dyno results that show everything from a 10hp gain to a 10hp loss with that swap. Someday when we get our Jeepspeed engine on the dyno, I want to compare them. Personally I would not do it without a lot of match-porting on the intake and head because the ports are very different size and it will cause all kinds of airflow issues.
 
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