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89 intake swap

revmeup

NAXJA Forum User
Location
Reno NV
OK....before you all go nuts...........I see a lot of info on this but none for an 89. Throttle body has a 3 bolt flange vs 4 bolt, cables come in from different directions, sensors have different plug ends, fuel rail bolts up different. This is just what I see on a quick review of both set ups. I can see I might be able to use a later tb and fuel rail, splice ends for the sensor ends. Reroute cables etc. Will the sensors work with a brainless computer? If I reuse my injectors are they the same length so I can use the later rail or do I need the newer injectors. Also, to this point no major mods to the engine. 215k so far. Runs good and idles smooth. Mileage sucks and could use more power. Nothing new there.

Anyone ever done this? Any feed back?
 
i was under the impression that just an intake swap on the renix wont do much as the real bottle neck is the head, so just adding a bigger intake(more air) wont help. as for the electronics, the tps is the problem. if you use the HO throttle body, the renix tps needs to be adapted to fit.
 
i was under the impression that just an intake swap on the renix wont do much as the real bottle neck is the head, so just adding a bigger intake(more air) wont help. as for the electronics, the tps is the problem. if you use the HO throttle body, the renix tps needs to be adapted to fit.

I just got my stroker block back together and was looking for the go jeep write up on the intake swap and stumbled across this. I was told to do the 99 intake swap (which i just purchased) in order to get more air flow into my cylinders to give the stoker its potential power.

WILL SOMEONE PLEASE TELL ME IF THIS IS TRUE. I just spent the money and time to have a 3 angle valve job done and assembly on a 87 head #2668. Not to mention the time it took for me to bolt it on the block.
 
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I just got my stroker block back together and was looking for the go jeep write up on the intake swap and stumbled across this. I was told to do the 99 intake swap (which i just purchased) in order to get more air flow into my cylinders to give the stoker its potential power.

WILL SOMEONE PLEASE TELL ME IF THIS IS TRUE. I just spent the money and time to have a 3 angle valve job done and assembly on a 87 head #2668. Not to mention the time it took for me to bolt it on the block.

well, you modified the renix head for more air flow, so i would suspect that the intake swap would be a good idea.

the OP has a stock renix head, yours is no longer stock as it was machined for better air flow.
 
The intake ports were raised on the later model heads. Im not sure if theres enough meat there to get the Renix ports to line up without ruining the airflow. I dont even know for sure that everything will bolt together without some grinding externally on the intake/exhaust manifolds. A HO head would be a good idea at this point.
 
Here's a pretty good writeup:
http://www.go.jeep-xj.info/HowtoIntakeManifold1.htm

You might want to look over the rest of Gojeeps site also.
http://www.go.jeep-xj.info/

Remember he is in Australia, and he's got RH steering.

go-jeep did the mod to a 95 egine with a different head then the renix head that the OP is using.

i would suspect that an increase in air flow would help, but there is a point in which it may not do as much as it would to a better flowing head, like the head on the 95 or a modified renix head.
 
well, you modified the renix head for more air flow, so i would suspect that the intake swap would be a good idea.

the OP has a stock renix head, yours is no longer stock as it was machined for better air flow.

All i did was the 3 angle valve job though. no porting and polishing.
 
so what are my options.

1. bolt the 99 intake up to my existing head, use ford 24lb fuel injectors, splice all the sensors and vacuum lines, get a 95+ steering pump mount, make an adjustable map, and just pray my renix system can handle it.
no more money than i planned on... or extra work

2. bolt up the 1990 intake i have (the 87 engine/head is going into my 90), use ford 24lb fuel injectors? w/ adjustable map, dont have to worry about splicing, and hope my stroker doesnt choke from lack of air.
sell the 99 intake so save some money... no extra work

3. buy a 7120 head, redo the 3 angle valve job and deck, unbolt the older head and bolt the 7120 on, bolt up the 99 intake, use 24lb ford injectors, splice all the sensors and vacuum lines, get a 95+ steering pump mount, make an adjustable map, and still pray my renix system can handle it.
Definetely more work and money. i probably couldnt sell the older head

thanks for any help. sorry for the hi jack oh, and im trying to keep this cheap!
 
why 24lb injectors on a renix stroker?

who told you to do the intake swap in the first place? did they realize you had a renix head? before they told you this(and got you in a fuss), what did you plan for when designing your renix stroker build?

i would rather have a well balanced functioning engine then one with an oversized fuel system. more and bigger is not always better.
 
Anyone ever done this? Any feed back?

All I can say is I'm running two Renix Jeeps with over 200k+ and our intakes are filthy. Here's a good example of a 200k+ Jeep intake which I pulled off an '89 in the JY. I'm trying to find time to clean mine out but I definitely lack power and MPG. Getting it back to stock is easier and might be all you need.

goodjy5.jpg
 
Since the 99+intake on renix head has been the topic of the week, I'm gonna go out back and compare the two manifolds and report back(have a spare 99+ intake and a 90 renix block w/o the manifold on it).
 
i was under the impression that just an intake swap on the renix wont do much as the real bottle neck is the head, so just adding a bigger intake(more air) wont help. as for the electronics, the tps is the problem. if you use the HO throttle body, the renix tps needs to be adapted to fit.


So if I use the existing TPS and install it on a later tb it will work?

Installing the HO head is easy enough to do and is part of the plan. But there is a lot more involved here. The head is a bolt on. The rest is all going to need to be modified.

Has anyone done this?
 
I was working on my jeep today so i decided to check it out. i have a ho and a renix intake gasket so i placed them on the renix head on the renix intake and on the 99 intake to note the difference. it appears that the 99 intake will actually bolt up fine and the ports match up for the most part. they match up on the bottom, left, and right perfectly. Unlike on the renix heads where the head porting only 45s to the cylinder on the Top side where the injector sits, the ho porting 45s across the whole width of the top of the port. so do you guys think i could just dremel the 45 out the whole width of the port on top? if so, is it just a matter of splicing the sensors and plugs?
 
Correction, the renix ports are cut out an eight of an inch lower on the bottom. so there would be a slight step down from intake to the head. i figure this shouldn't be a problem since it will actually be a bigger opening on the head side
 
Here's a pretty good writeup:
http://www.go.jeep-xj.info/HowtoIntakeManifold1.htm

You might want to look over the rest of Gojeeps site also.
http://www.go.jeep-xj.info/

Remember he is in Australia, and he's got RH steering.

I have read this all and searched all over. Although this is really good stuff, its not even close to the same. Mine is a renix. None of the wiring or cables are the same. I get the swapping the p/s and using the HO head. That is not what I need to know.

What we need here is someone who has done this who knows the differences and what was done.
 
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Basically everything in my Jeep is 1993 except for the body, electronics, and axles which are 1987.

The Renix TPS needs to be adapted to work with the HO TB. They work differently and there is no way to make the HO TPS work. The HO TPS is non-adjustable and it fits directly on the end of the throttle plate's shaft. The Renix TPS has a little lever that is moved by an arm on the throttle shaft and the whole unit is movable to achieve adjustment. The Renix TPS must be adapted so that it works in the same way with the HO TB. There is a kit available from Hesco, but it is pricey and many people just fabricate something.

The Throttle cable and AW4 cable(if applicable) also go to the TB over the engine from the right side as opposed to the Renix setup where everything is on the left. I used the cables from the later Jeep to make it work and I don't know if it can be made to work with the originals. I did not have Renix cruise control to deal with but on the 93 that I was stealing parts from that cable came over the engine too. I dunno how the Renix cruise works, but I would assume it's on the left side as well to meet the speedometer cable.

You want to use the Renix fuel injectors as the newer ones would all be using too much fuel. a 91-95 fuel rail can be easily adapted to hook up to the lines. After that they switched to a returnless system, without a regulator on the rail, so if you are using a 99 intake, then a fuel rail with a return must be adapted to it in order to use with the Renix fuel pump setup. I used a 93 intake and rail so all I needed to do was add some rubber fuel line and hose clamps.

The only other issues with the intake alone would be the Renix MAT sensor, which screwed right into my 93 intake. The MAP sensor tube needs to be routed to an empty nipple on the newer intake, as the HO TB does not have a hole in it for said tubing. I just used a rubber elbow on the end of the plastic tube and hooked it up to an unused hookup.

I don't know about the power steering pump, because I believe I swapped pump/box and hoses from the donor vehicle at the same time. I think that the original hoses hooked up at different angle on the box end, so you would most likely need to use Renix hoses no matter what pump you end up using, unless you have the luxury of having an entire vehicle to scavenge for parts. I know nothing about adapting Renix pumps to later manifolds, but I believe that the later models (somewhere after 95) are more difficult to adapt.

Edit: fuel injectors
 
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VERY COOL......thanks for the help.

I spent several hours in a jy so I could look at the 89, 91-95 and a 2000 side by side. From what I could tell, it can be done but the tps is the big issue. I was going to go back an try to install the 89 tps into a 91-95 tb. Not sure if it will operate but thought if it fit it might. After reading your comments I will need to do some more homework And yes I do have cruise. After looking at each setup I might have to skip that or see if I can mod the existing to work with the 91-95 tb. That will take some trial and error for sure. It also looks like the tc from the 91-95 will swap right over and same with trans cable. Glad to hear you were able to make them work. I'll have to take a closer look at the MAT and the MAP as well. So the plan is to do the HO head, 2000 intake and p/s, 91-95 tb, fuel rail, tc and trans cable, 89 injectors and then adapt the rest.

Thanks again
 
Why do you need the trans cable? it looks like it was long enough. I just grabbed the throttle cable? As far as the tps goes, i took both of the tbs apart and inspected the butterfly shaft operation along with the tps. the tps is rotated exactly 90 degrees clockwise on the 91-95 with a little different setup. I am just going to cut the ends off the butterfly shafts, tig weld the older shaft end onto the new shaft, and space out the older tps the right deistance with some washers. seems like it should work without any problems. Something i noticed, the 87 tps has 6 wires, 2 of each color going to the different plugs, and the 91+ tps has 3 wires. Why couldnt we just splice the new tps up to the existing harness and splice the wires of the same color together? I figured, same color wire, same voltage just sent to a different location?... I also ported out my renix head and bolted up the 99 intake. Seems like its going to work without problems.
 
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