97tj 4.0 in a 88 xj

what will i need to do to make a 97 tj motor in a 88 cherokee will the 88 intake work on the 97 i know the exhaust wont or would it be easier to find a obdll computer and harness

Not to be a putz, but this has been covered (mainly with newer XJ engines into earlier XJs,) here before, so you can get a general idea if you get a little creative with the Search function. I'd toss you a few bones, but I don't recall any of the thread titles offhand.

However, I'm also fairly sure that the TJ accessory mounts may be different, so you will have to account for that (swapping over XJ accessories probably won't fly.) And, note that the alternator used in your 88 was a Delco CS-130 with an internal regulator, the 1997TJ uses a Nippondenso with an external regulator. If you adapt the RENIX controls (1987-1990 XJ/MJ/YJ w/AMC gasoline engine) to drive the 1997TJ OBD-II engine, you'll need to add an external regulator to make the alternator work, unless you retrofit the Delco to the OBD-II engine.

If you decide to bring over the OBD-II controls as well, you'll have to bring over pretty much all of the wiring from the TJ, and you're going to have to adapt most of it from the fuse block forward (if not just all of it.)

Also, note that the heads and manifolds will be different between the RENIX engine and the OBD-II engine - the intake ports are higher in the head, the intake manifold has different accessory mounts, the throttle body is different, the oxygen sensor works on a different principle, the TPS works in the other direction (it's a variable resistance either way - but one works on a decreasing resistance as the throttle opens, and the other increases resistance. I don't recall which is which offhand,) the exhaust manifold is different (not only will there be no provision for the EGR valve - which shouldn't have been installed by the factory anyhow, y'ask me, but the collector will be in a different place and won't work with your OEM downpipe. You'll need to have a new one made,) the oxygen sensor works on a different principle (variable voltage instead of variable resistance used as a voltage divider - but you can go ahead and retrofit an earlier HEGO into a later manifold - they're the same thread, M18-1.5. Plugs will have to be installed in any other bungs that don't have HEGO sensors in them, since RENIX only answers to one. OBD-II usually looks for four...) and a few things I'm not thining of at the moment.

Is it doable? Sure.
Is it difficult? Absolutely.
Is it insurmountable? Depends on skill and tooling available. And experience in fabrication & mechanics. And electronics. And ...

You're letting yourself in for a fun job either way - whether you move the controls over with the engine, or adapt the newer engine to the older controls. Not something you'll be readily able to handle in a week-end...

what about puttin a renix head on the OBDll engine then just using everything from the 88

Capndave92yj88xj said:

what about puttin a renix head on the OBDll engine then just using everything from the 88

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That could easily be done, but you're not going to benefit much that way. You're better off going in the other direction - OBD-I or OBD-II (#7120 or #0630) cylinder head on a RENIX short block. The RENIX short block is tougher than the hinges of Hell, the OBD heads breathe better, and the RENIX TPS can be adapted to fit the OBD throttle body (that has been covered here as well - with pictures - and it will probably be easier to dig up.)

That's why the intake ports are higher on the later heads - to reduce the angle that the intake airstream had to turn, and therefore increase the port flow. There's nothing at all wrong with the RENIX short block, but the heads invariably benefit from some massage work. If you throw on one of the two heads mentioned (#7120, 1991-1995; or #0630, 1996-1999) you'll see noticeable gains from improved intake airflow. Ideally, throw on a 1999-up intake manifold as well, and the Ford SB throttle bodies (5.0/302ci and 4.6/281ci should fit, making a bored-out unit easier to find. However, a bored throttle body will improve part-throttle response more than power output, be advised.)

That 1997 TJ should have a #0630 cylinder head, which is a notable upgrade for you. You can find the four-digit ID number on the manifold side of the head, above the #3 & #4 exhaust ports, outside the valve cover.

yea i know the heads are better but just looking for a cheap ways to put a motor in this jeep bc im not want to put much into it i picked it up from a friend for dirt cheap and found a 97 4.0 for 100 with 100k on it what if i ported the renix head and intake
and right now im driving a yj 4 cyl with 31s so no matter what the 4.0 renix will be better that the 4 cyl

Capndave92yj88xj said:

yea i know the heads are better but just looking for a cheap ways to put a motor in this jeep bc im not want to put much into it i picked it up from a friend for dirt cheap and found a 97 4.0 for 100 with 100k on it what if i ported the renix head and intake
and right now im driving a yj 4 cyl with 31s so no matter what the 4.0 renix will be better that the 4 cyl

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Before we go rabbiting on about "what can be done," perhaps a question is in order. "What is wrong that you are trying to fix?" Is the short block shot? You can swap the OBD short block under the RENIX head, and get running that way rather quickly. Is the head shot? It's more work, but the later head will drop right onto the earlier short block.

It's just difficult to give an effective answer when the question remains unknown...

the jeep does not have a motor my friend blew his and took the one that was in it but i can get the head intake and exhaust from his old motor the head only had about 1000 miles on it
but yes i just want to know now if i could put the 97 block under the renix head and use everything from the 88

Capndave92yj88xj said:

the jeep does not have a motor my friend blew his and took the one that was in it but i can get the head intake and exhaust from his old motor the head only had about 1000 miles on it
but yes i just want to know now if i could put the 97 block under the renix head and use everything from the 88

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Now we're getting somewhere!

Putting the late short block under the RENIX top end would probably be easiest, and should be doable in a week-end or so.

Two things to address:
1) Find the engine block drain plug (should be down on the manifold side of the block,) remove it, and put the RENIX ECU temperature sensor in its place. Not a perfect solution, but easier than drilling and tapping a new hole (the drain plug should come out of a hole threaded 3/8" NPT)
2) Find a casst boss down by the oil sump rail. Drill and tap to accept the knock sensor (you do not need to go through! I believe you D&T M10-1.5x20m/m deep or so. A solid mechanical connection is all that's required, the knock sensor does not need fluid contact. Verify the threads on the replacement stud when you source it.)

Apart from that, you should be able to just drop the package in. Use the alternator brackets from the RENIX block (they should fit the HO block readily) to mount the Delco alternator - it's internally regulated, as I mentioned before, the wiring is already present, and I find Delcos more reliable than NDs anyhow.

I have a 93 4.0 in my 87, running Renix electronics. I used the later intake, and adapted the TPS, there is a kit from Hesco to do this, but I just fabbed one. I also used the Renix fuel injectors. It will run with the HO injectors, as I did for several years, but I got 11 mpg, which is back up to 16 now with the Renix injectors. This would be more important for you, as the injectors got bigger as the years go on. I also had to use the Renix alternator, I don't remember about the bracket. There was a hole in the 93 block for the knock sensor, just needed to be tapped, but I hear they stopped making the hole at some point.
Many people have swapped the Renix intake onto the later head with no problems, I did not, but I held it up there and it seemed to line up. I used the later intake/TB, as it is better, but if you need to pass an inspection you should probably use the Renix manifolds in order to keep the EGR system. I ditched the EGR entirely. There is no hole for the EGR in the later exhaust/intake manifolds. If you ditch it in lieu of the later intake, you'll need to plug the hole in the header, or use a later header. I had an aftermarket header so I welded over the hole. It is absolutely essential that the Renix CPS reads a Renix flywheel/flexplate, which will not be a problem unless you are using a newer trans as well. Basically, just swap over everything electronic, and you're good.

Slip Kid said:

.
Many people have swapped the Renix intake onto the later head with no problems, I did not, but I held it up there and it seemed to line up.

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Wrong, i just got out of the garage not 5 minutes ago and decided to go to bed because the ports did not match up at all and i got pissed becuause i'm doing the same project. I held a 99 (0630 head) gasket up to a renix intake and the renix has a much taller lip where the injector spits the fuel into the intake. The gasket would block a lot of the fuel spitting into the intake if you bolted it up. The head would most likely do the same. I think the ho head has to be ported a little on the intake side to match up to a renix intake. The exaust ports however seemed to line up properly.

That's not to say it would not run. It has been done this way, and worked.

Well if it’s been done that way then about 1/4 of the intake ports total area was blocked. I would never hinder performance like that in any of my rigs.
I'm going to go pick up a renix gasket today and see what that looks like held up to the 0630 head. Then I’ll scribe the 0630 head ports onto a piece of paper and place that up against a renix intake, exhaust and gasket and take a picture. I'll try and get that posted up here tonight after work so you all can reference. That should be around 8pm tonight. It may ultimately just come down to taking a dremel tool to the 0630 gasket. Capndave; if this works I’ll let you know as this may be the easiest solution for you. Changing out an entire wiring harness seems unnecessarily arduous for you. I don’t think this task would call for that much work. You’ll be happy in the end with your stock electronics as the renix computer is indestructible and adapts on its own to anything you throw at it. That combined with the low mileage HO power plant and you’d have a stout set up

bump

Well i didn't want to post this untill i had finished the install to tell you if it workd and if i had power but i said i would post pics so here we go.

You have to grind the 2 bottom mounting dowels on the intake that slide onto the head studs 3/8 of an inch so you can move the intake up.
This then mismatches the upper portion of the intake ports but matches up the bottom. I have scribed on the gasket with a pencel to show how high up the injector holes sit now. I am grinding away at the head to line up the injector holes. I also decided to take the sander wheel for my dremel to polish up the exauhst ports. Its slow going becuase my dremel keeps on overheating. Hopefully i don't screw anything up. I'm using a renix gasket and will use lots of coppper anti sieze when i put it together to hopefully eliminate any leaks. And i'm hoping the soaked towels will keep all the metal shavings out.


Shot with DSC-T1 at 2009-06-08


Shot with DSC-T1 at 2009-06-08


Shot with DSC-T1 at 2009-06-08

its a little nerve racking, i'm not going to lie. I'll probably end up bying another gasket as i might mangle this one.

ok so i got screwed on the motor he sold it even after i told him i was gonne come pick it up
no im goin for a 92 cherokee motor
if i can get the harnes and computers would i be able to hook it up to power and go?

Same deal, entire wire harness and computer, or adapt.

I'd way rather do what i'm doing than change a the whole harness. Especially when it'd be a downgrade, in our case.

is there anyway to just use the HO intake

Capndave92yj88xj said:

is there anyway to just use the HO intake

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HO intake on Renix 4.0? The TPS would need adapted, and, ideally, you would use the HO's head as well, since the ports don't exactly match. There is a recent thread on here about making it fit the old head, but you would probably want to use new the head. Using the HO intake would make it impossible to retain the Renix's EGR system, the valve would go in the trash, and the hole on the exhaust header would need to be plugged, or a HO header would need to be used. The EGR system is considered emissions equipment, so its removal is generally frowned upon, in fact in some states you will be immediately attacked by a large group of ninjas.

i have a 92 xj engine complete and i dont care about emissions
how would i got about adapting the tps i dont wanna buy the hesco i wanna do it cheap