Any Completed 4.0 Swaps Running Around?

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tgreese
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Joined: Fri Jun 08, 2012 6:31 am
Location: Medford MA USA

Re: Any Completed 4.0 Swaps Running Around?

Post by tgreese »

Cecil14 wrote:I know they changed the head from Renix to HO, but I'm not sure if it's enough that you can't make an HO manifold fit or not. You could always swap heads, but if you've got any kind of investment into your Renix head or a questionably worn bottom end that's probably not the best plan.

I've got my wiring notes around here somewhere...they're not spectacular, but anyone that wants them is more than welcome to em. I do plan on going back through my wiring here real soon. I've got some other problems I need to address, and I want to upgrade some things as well. If I can get the motivation together, I want to draw out my wiring in Autocad. Maybe with a few beers...


aa
The Renix head is low rise like the 258, but high compression like the 4.0L HO. Kinda doubt you could make the HO manifold fit, and you would not get the same benefit from a HO head that a 258 would.

Rather than convert to Mopar/Bosch(?) MPI, you can junk the Renix electronics and run a Megasquirt system. http://www.msextra.com/forums/viewtopic ... 31&t=49969 Been done before - search the net and find plenty of references.
Tim Reese
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MJMadness
Posts: 101
Joined: Wed Aug 06, 2014 1:46 pm

Re: Any Completed 4.0 Swaps Running Around?

Post by MJMadness »

tgreese wrote:
Cecil14 wrote:I know they changed the head from Renix to HO, but I'm not sure if it's enough that you can't make an HO manifold fit or not. You could always swap heads, but if you've got any kind of investment into your Renix head or a questionably worn bottom end that's probably not the best plan.

[...]

aa
The Renix head is low rise like the 258, but high compression like the 4.0L HO. Kinda doubt you could make the HO manifold fit, and you would not get the same benefit from a HO head that a 258 would.

[...]
Wrong. The Renix head is mid rise. It is not like the 258. It's roughly between the 258 and the HO head. You can put a HO intake on a Renix head with only minor port misalignment, just make sure you use the HO intake gasket. I port matched the HO intake to make it closer to the Renix head, I did not port match the Renix head, but I believe it is possible. However, neither is necessary. The Renix head does not flow as well as the HO, but is not far off, if anything the Renix intake manifold was the real flow restriction.

I have a Renix XJ with the early HO intake on it that's been adapted to run the Renix EFI, using the Renix head.

MJMadness
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Joined: Wed Aug 06, 2014 1:46 pm

Re: Any Completed 4.0 Swaps Running Around?

Post by MJMadness »

backroadin' wrote:Oh, and if you go carb, a 258 distributor will drop in. I run a pertronix unit in my original '73 dizzy in the stroker. For carb swap info on the 4.0, search 4.0 head swaps on here, ifsja, and various cj forums. Most swap to the MPFI, but some folks who do that swap on their 258's elect to keep the carb. There's some modifying of the intake and some bracketry issues that need to be addressed, but nothing major. If it's a serpentine belt setup on the 4.0 it's a little trickier. I don't know if anyone has ever put an adapter onto the renix intake and run a carb - not sure how that would work. You could do a junkyard TBI setup on it though - if you really wanna get into it deep! :)
As mentioned, jeepstrokers website has some info as well, a few of those guys are running carbs.
You can bolt an Offenhauser 4 barrel 258 intake the to the Renix (maybe not the HO, have not tried it) head. You will need to redrill the dowl holes, or slot them and just watch where you install it. You will need slightly larger diameter washers for the attachment bolts, and to spend a few minutes grinding them to the ideal shape, but it is far from rocket surgery. I used the factory Renix header, but it would probably clear with any of the aftermarket or HO ones. Use the Renix intake gasket when doing this.

I did it to run propane instead of the Renix EFI, as this allowed me to run a generic Holley throttle plate/Impco 425. Performance was quite good with a HEI disty (AMC 360 drive gear on a GM I6 disty). I probably wouldn't do it again, as my love affair with propane is more or less over... But it did make for a bulletproof damn near zero wire setup that would run at all angles.
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Cecil14
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Re: Any Completed 4.0 Swaps Running Around?

Post by Cecil14 »

MJMadness wrote:You can bolt an Offenhauser 4 barrel 258 intake the to the Renix (maybe not the HO, have not tried it) head.
258 intake on an HO head is easy:

http://www.geocities.ws/cecil_odo/strok ... ntake.html

Just grind the bottom of the dowl holes a bit so the intake sits on top of the pins instead of over them.


aa
1983 J-10 - 4.6L(MPFI)/CS130D/Hydroboost/NV3550/D300/44/44/3.54/Disc-Disc/32s/42 gallon 'burb tank
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