• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

customizing renix for a 60 mm + TB

X

xjrugger

NAXJA Forum User
Location
long island, new york
I hear that using the intake manifold from an newer HO model will make it so I can use a 60 mm bored TB. I want to gat more power and i have covered the whole TB thing, so my new guess is why should i put money into a renix model head. Why not start converting so when i someday do a stroker i can do it right. Or should i just wait til this motor is worn and convert a HO in to do a stroker. My motor now only has in the 135000 miles area so i feel its still a great motor. Should i put on a 99 intake manifold from a tj (which i can get for dirt cheap) and use that to start and then eventually change the exhaust manifold. Sorry for the long thread but i'm looking to do the TB ASAP, after a year of debate BTW its an 88 4.0 i want to put the manifold on. And after searching i see Dr Dyno says something about having to customize a power steering pump bracket and possibly a new PS pump. Why this? Is there any other customizing i would have to do to put the 99 manifold on the 88?
 
Last edited:
The problem is that if you have a RENIX head, the HO manifolds won't "just bolt up" - there's work to be done. You're going to have to modify the mounting flange to accept the RENIX bolt pattern - the HO intake ports are a little higher, and therefore don't line up.

You've got a couple options here -
1) Bore out the RENIX intake/throttle body mounting surface to 60-62m/m, to clear the 60m/m tbody bore.
2) Change out the entire top end - use a 91-95 head, intake, and exhuast. You'll want to retain the RENIX thermostat housing (unless you can find a plug, or have a use for the additional temperature sender) and the 91-95 head will also retain the port for the CTS that reports to the gage in the panel.
3) Adapt the HO intake to mate up to the RENIX head and RENIX exhaust (the flange may be a different thickness, and there will be a little more room between the intake and exhaust flanges on the head,) or go with one of the alternatives.

The #7120 (1991-1995) head and intake/exhaust may be the best swap - the #7120 is generally accepted as the "best-breathing" head out there, and it will net you more of an increase than the intake swap alone. Also, you'll have to adapt the TPS for the HO tbody to the RENIX setup (especially if you have an automatic - then you've got the "double" TPS) or just make an adapter plate to set the RENIX tbody onto the HO intake (since they're a different bolt pattern - the RENIX takes three bolts, the HO takes four. I don't recall the bolt circles.)

5-90
 
The 99 intake does not have provisions for an EGR valve, and without an operational EGR valve, you will fail smog (in CA, and maybe NY, as I recall NY has adopted CA's standards and methods.) I think there may be a way to TIG-in an EGR mount, but it would require extensive modifications.
 
CRASH said:
The 99 intake does not have provisions for an EGR valve, and without an operational EGR valve, you will fail smog (in CA, and maybe NY, as I recall NY has adopted CA's standards and methods.) I think there may be a way to TIG-in an EGR mount, but it would require extensive modifications.
Click to expand...


If that is the only issue for the EGR valve them im not worried i can make it pass smog. If there r other issue that stem from the EGR, than there is a problem.
 
5-90 said:
The problem is that if you have a RENIX head, the HO manifolds won't "just bolt up" - there's work to be done. You're going to have to modify the mounting flange to accept the RENIX bolt pattern - the HO intake ports are a little higher, and therefore don't line up.

You've got a couple options here -
1) Bore out the RENIX intake/throttle body mounting surface to 60-62m/m, to clear the 60m/m tbody bore.
2) Change out the entire top end - use a 91-95 head, intake, and exhuast. You'll want to retain the RENIX thermostat housing (unless you can find a plug, or have a use for the additional temperature sender) and the 91-95 head will also retain the port for the CTS that reports to the gage in the panel.
3) Adapt the HO intake to mate up to the RENIX head and RENIX exhaust (the flange may be a different thickness, and there will be a little more room between the intake and exhaust flanges on the head,) or go with one of the alternatives.

The #7120 (1991-1995) head and intake/exhaust may be the best swap - the #7120 is generally accepted as the "best-breathing" head out there, and it will net you more of an increase than the intake swap alone. Also, you'll have to adapt the TPS for the HO tbody to the RENIX setup (especially if you have an automatic - then you've got the "double" TPS) or just make an adapter plate to set the RENIX tbody onto the HO intake (since they're a different bolt pattern - the RENIX takes three bolts, the HO takes four. I don't recall the bolt circles.)

5-90
Click to expand...

Bt "double" TPS what do u mean?
I want to get more power (gears have been done) without tearing the head off b/c the motor still runs GREAT as i knock in wood. Yet i would like if possible to put a bored throttle body and do the air intake that will still be able to mate to a newer head when i someday get the money to do a stroker. What else would i have to do to fit the 99 intake on the renix. Or should i use like a 91-95 head to avoid EGR issues like Crash said? Also, will there be power steering pump issue with this like i have seen Dr. Dyno mention?
 
Why don't you just get a TB for the Renix head? A 58 MM Renix TB will flow as much as an unported Renix head can handle, anyway.

XJ armor sells them
 
CRASH said:
Why don't you just get a TB for the Renix head? A 58 MM Renix TB will flow as much as an unported Renix head can handle, anyway.

XJ armor sells them
Click to expand...


I'm going thru JeepersCreepers for both, what do u think of them

I just didn't want to put too much money into a motor i will eventually overhaul with a new head, that's why i was thinking of the newer intake manifold since it could be used on the newer head when i do a stroker.....someday.
 
I don't understand why you can't build your stroker with a Renix head, I did, and it is quite lovely.
 
CRASH said:
I don't understand why you can't build your stroker with a Renix head, I did, and it is quite lovely.
Click to expand...


So can a stroker kit be purchased for the Renix head that is just as powerful as the one for the newer model 4.0?

If so then i agree, it's just that i always see the renix getting brought down b/c it came out of the factory producing less.
 
I put a 93 HO into my renix system.
I made an adapter for the automatic tranny TPS sensor by using longer bolts/sleeves and notching the male TPS sensor to make it a female to fit the male shaft on the newer intake.
I elimiated the EGR and just passed a smog test yesterday in Ohio; I was sure it'd fail, but it did well.
The exhaust manifold is routed differently and bolts up differently (like the intake), so you'd have to have exhaust parts made to adapt. I had a complete donor rig so I had most stuff handy from one or the other.
 
If you want to go stroker, think about keeping the Renix parts. The computer has wide lattitude and handles the change well, some people say better than the Chrysler computer. The Renix head doesn't flow quite as well, but port it (see Dr Dyno's site). The dimensions in the head (volume) are better for avoiding knock than those in the HO head, and the Renix setup uses a knock sensor.....good solution to the knock problems that have many HO strokers burning high test gas. I drive both a 1990 (Renix 4.0) and a 2001 (HO 4.0), and in stock form the Renix has more low rpm torque. The 2001 HO is faster at higher rpms. I like the Renix engine!
 
You must log in or register to reply here.

Similar threads

O
2000 XJ Failed Colorado Emissions high CO
2
Replies
27
Views
2K
Ken M
K
X
Making the frame purdy
2 3
Replies
48
Views
733
Xjin85
X
4
Timing gear?
Replies
3
Views
101
4x4JeePmaNthINg
4
V
Engine rebuild guidance
2
Replies
34
Views
6K
RCP Phx
R
Saudade
Still More Salvage Yard Gold
Replies
4
Views
220
Saudade
Saudade
Back
Top