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What's the difference?? Any (Heads)

AboveNBeyond

NAXJA Forum User
Location
Northern AZ.
Hello all,
I have a 96 motor (I do not think it is was an HO) swapped intoan 89 and all the 89 stuff was swapped over to the 96 motor.

What I would like to know is whats the difference between the 96 and 89 head in regards to the exhaust. Are the ports the same size and the bolt pattern and so on the same?

I am asking because I will be replacing the exhaust manifold soon and see the 89 and 96 use different headers. Was it because the head or the chassis?

Can I use a 96+ header in an 89 chassis?
 
If you have a 96 motor, then it is an HO.

The ports on HO heads and Renix heads are different. So you can't interchange the headers.
 
Muad'Dib said:
Are you using the 89's head?

No It is the long block from an 96. And I guess that explains why my manifold looks a little different then my buddies 90.

So if I get a header for the 96 it should have no issues fitting the 89 chassis or working with the intake?
 
AboveNBeyond said:
No It is the long block from an 96. And I guess that explains why my manifold looks a little different then my buddies 90.

So if I get a header for the 96 it should have no issues fitting the 89 chassis or working with the intake?

So your using a 96 head and the 96 intake manifold right? Then yes, get a exhaust manifold for a 96 and you will be just fine :D
 
Muad'Dib said:
So your using a 96 head and the 96 intake manifold right?

Well see I can't say for certain, I did not put the motor in myself, I bought just as it was completed... I think it is the 89 manifold, I know it has all the renix stuff on it still? Where the intake ports and bolt pattern different? Maybe it is the 96 intake but with the renix throttle body on it.

Will they interchange?
 
No, a Renix TB won't work on a 96 manifold.

So it sounds like you have a 96 block, a Renix head, and a Renix intake manifold.

IF this is the case, then you need a Renix header.
 
xjohnnyc said:
So it sounds like you have a 96 block, a Renix head, and a Renix intake manifold.

How can I tell, because I was told it is was a 96 long block. My Valve cover is the black more square one, not the Aluminum style I have seen, dunno if that matters just thought maybe the bolt pattern of the valve covers might be different??
 
Well, my line of reasoning goes like this - If you have a Renix throttle body, you must have a Renix intake manifold. If you have a Renix intake manifold, you must have a Renix head. And if you have a Renix head, you need a Renix header. Is my logic flawed? :dunno:

And valve covers are interchangeable between Renix and HO, so that is not a sure-fire way of telling.
 
xjohnnyc said:
Well, my line of reasoning goes like this - If you have a Renix throttle body, you must have a Renix intake manifold. If you have a Renix intake manifold, you must have a Renix head. And if you have a Renix head, you need a Renix header. Is my logic flawed? :dunno:

And valve covers are interchangeable between Renix and HO, so that is not a sure-fire way of telling.

x1000

Better yet, take a pic of your current intake and exhaust manifolds and post them here.

Also, does your exhaust manifold have an EGR valve attached to it? If so its 100% RENIX.
 
OK wait up... I let me start with this question...

In regards to the exhaust and intake manifolds, do they mount the same?

Same port size and bolt pattern or no?

Would the 89 manifolds physically be able to mount to the 96 motor?

(Yes my intake has the egr and the tube to the exhaust)
 
AboveNBeyond said:
OK wait up... I let me start with this question...

In regards to the exhaust and intake manifolds, do they mount the same?

Same port size and bolt pattern or no?

Would the 89 manifolds physically be able to mount to the 96 motor?

(Yes my intake has the egr and the tube to the exhaust)

Way back in post #2.

xjohnnyc said:
The ports on HO heads and Renix heads are different.

Seems that you do have a Renix head.
 
AboveNBeyond said:
OK wait up... I let me start with this question...

In regards to the exhaust and intake manifolds, do they mount the same?

Same port size and bolt pattern or no?

Would the 89 manifolds physically be able to mount to the 96 motor?

(Yes my intake has the egr and the tube to the exhaust)

Exhaust? Probably.

Intake? Not easily.

When the HO engine came out for 1991 (#7120 cylinder head casting,) the intake ports were raised 5/8" from their locatoins on the #2686 (1987-1990 "RENIX") head in order to improve intake flow (by easing the restriction caused by the bend. Reduce the bend, reduce the restriction.)

Exhaust ports are probably in about the same place, and about the same size - until the #0331 head (1999 WJ/TJ & 2000 XJ on up,) when they were reduced in size to "improve catalyst light-off times." I think they were reduced some for the #0630 head (1996-1998/1999,) but I can't swear to that, nor have I seen the two heads side by side. Why for do you think I'm trying to collect cylinder heads? :D

Mounting the early intake on the later head - or contrariwise - has been done, but it's pretty obvious (and it is easier to mount the RENIX intake on the HO head, instead of the other way about.)
 
AboveNBeyond said:
So I can take pics but I don't know if anyone could tell what head it is from that, is there a number easily visible? My motor is gunk free.

It doesnt really matter to the question at hand. You said you were replacing the exhaust manifold soon, and didnt know which one to get. You currently have a RENIX exhaust manifold. So get another RENIX and be good to go.

Now if your curious about what you actually "have" then i can understand you trying to find the casting number of your head. But im about 99% sure that they used everything from the head up from the 89 you had, and used the assembled block from the 96. If they didnt, then they would have / should have told you that parts were not fitting and they had to do some modifications to make the Renix head / intake fit on the 96's head.. and charge you even more then what they already raped you for.
 
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