bootht99

Just like the title says.

The newer manifolds are better flowing, and i was wondering if i could pick one up along with a TB at a wrecker, then put it on my 1990 renix. This would also allow me to run TB spacers. I want to know this before I get my renix TB bored out.

winston427

Will it bolt in with no mods, yes. Will it run, yes. Will it run right, no. The ports on the Renix head and the H.O. head are different and do not match up. You can get it to run but it will not flow well and will have an effect on both performance and fuel mileage. Secondly, if you have not already purchased the TB spacer, DON'T. They do nothing for these engines and are a waste of money.

bootht99

alrighty. I was doing some readin and apparently the intake ports are about 1/8 off, so the will mess it up. thanks for clearing that up. 60mm TB here i come!

91familyxj

I have a 88 head and a 91 intake in mine and it runs just fine for me. Yes I know its not a perffect match but hey it works for me. There is a TB spacer for your TB but like said before its a waste of time and money.

huntingman2706217

i had a 89 itake on a 96 motor and when i stuck a 01 intake on i didnt really notice much... it ran fine... but doesnt make it right i guess... probly was getting warmer then it should...

L-ucky-S-ix

I'm going to bump this back up for lack of info when searching. I searched for more than a few hours and can't find a good answer!

I have a 1987 4.0...

Is it possible to swap a 99+ cylinder head, intake manifold and throttle body onto my Renix without any issues?
Will the exhaust manifold from the 99+ be necessary when swapping the 99+ head onto the 1987 4.0?
Will I need to utilize the newer power steering pump and bracket as well?

Looking at this thread (https://www.cherokeeforum.com/f51/re...ts-easy-47578/) is way too confusing to find the answers since everything is backwards.
This is the closest I can get to answering my questions...(https://www.cherokeeforum.com/f2/intake-swap-34009/)

I am aware of the 99+ intake manifold upgrade and all of its constituents for the 91-on-up motors but there are no answers for the early ones.

trans_am7935

first of for next time, please start your own thread, but in the case oh heads, you do not want the 99, it flows less then the 91-96 head, it also will not accept the temp sensor for your gauge and the temp gauge will not work on your dash.

the intake manifold will work but you will need a different throttle cable, reroute the vacuum lines, and the new P/S bracket will be needed.

and on the renix motor, you will probably just loose gas mileage cause the computer is not self adjusting and will not compensate for the more airflow and different vacuum readings from stock, so IMHO, not worth the swap.

L-ucky-S-ix

That's a good point. Will this not be a sufficient solution to that?
http://www.go.jeep-xj.info/HowtoMAPsensor.htm

Thanks for the info.

Also, with the new throttle cable... is there one reason for that? Is the existing throttle cable going to be too short or too long?

huntingman2706217

Throttle cables are different... you'll want a throttle.body from a 94 Cherokee... this way most of you sensors will still plug up... all throttlebodies are the same from 91+ Cherokees bit the sensors are different...you will still need to splice on the newer style tps sensor... read my renix/HO hybrid thread in the write up section... it will explain basically everything you will be doing... you will need a newer model header for the head but they are made at a different angle at the down pipe so your looking at reworking exhaust as well... need a 91-98 fuel rail and injectors and throttle cable... power steering is all different... its not worth it... but I found I bought a 89 Jeep with a 96 motor and was still all renix stuff on it so I had to make it right... worked great and is very possible... just don't think its worth the time and money...

L-ucky-S-ix

Thanks for the input.
I looked at your thread and had to close my eyes as it was extremely hard to read.
Those model year suggestions may make it a little harder but I'm not looking at doing this thing tomorrow. I'm learning this vehicle from head to toe and then I will be sourcing the parts one by one as they become available.
I was considering this as a fun project in the future so I'm not entirely set on doing it quite yet.

My plan was to get the cylinder head hot tanked.
Get the intake manifold media blasted.
Send the throttle body in as a core for a bored unit.
Install with some brand new injectors with the later fpr.
Spend the $10 to create the Adjustable MAP sensor for more or less fuel.
New head gasket, intake/exhaust mani gasket, valve cover gasket, fuel filter, and PCV oil catch.
Powder coated valve cover
Electric slim fan

I believe my budget for this will be under $650. Thanks for the help!

huntingman2706217

itll be easier to read the more you learn before you buy... once your in there probably... lol... that was awhile back when i did it... probly could go back and make it better but its not something that is done often... most people just replace the whole harness and computer... but i discovered it not needed...