4.0 Short Block... Thinking Out Loud

[neohic]

You're just sour you didn't claim another in the HO following.  :yes:

 

... as far as the long standing HO to Renix debate, I could really go either way. Sorry, Cruiser... I'd consider me a draw. Fortunately, that also means that Don didn't win either. 

[cruiser54]

 

 

You're describing exactly what I've done twice now. HO motor into a Renix. 

 

Computer could give 2 $#!&s what the engine is. 

 

Did I ever post this for you?

 

HO myth buster

 

 

Renix in 90 made 182 HP. HO in 91 made 190 HP. That's 8 HP difference. 

 

HO only made more HP than Renix at higher RPMs and not a bit more torque. HO had 58 mm throttle body versus a 52 mm throttle body on a Renix and also had a better design header. See where I'm going with this?

 

The whole 8HP was not mostly from the head, but from the bigger TB and better exhaust manifold.

 

Put a 60mm TB from www.strokedjeep.com on your present head, eliminate the "crush" in your headpipe with proper re-routing, and go for it. 

 

HO stands for Highly Overrated.

__________________

 

 

The same tired old litany again. And again. And again.  :shake:  You need to come up with some fresh material.

 

Litany: A tedious recital or repetitivly boring series of meaningless gibberish.  

 

The truth lives on. I'm spreading the word. 

[xjrev10]

Keep the Renix. Find a different harness to swap in if the wiring bothers you.....

 

Ax-15 or nv3550 -or- nsg370. JP mag did one awhile back. That would be badass for a play toy.

[Guest]

Vote goes to Cruiser and Rev for the notion of getting a harness to mate onto the truck. Of course, there's problems with that notion, but it would allow you the peace of mind to have everything sorted out in one go.

 

Had the same dilemma when I did the heater core and took the entire cab apart. Ended up rewiring a good number of things from AMC's hodgepodging and one previous owner's attempt at adding in some sort of amplifier (?). Happy with the results, and no longer worried about something going awry at the worst possible time.

[Doc.]

Sell your truck, buy a newer one with a stick. I also don't like shifting. It's tough to do much of anything (drink, eat, play with radio, etc.)when that right hand has to keep shifting all the time. I have a Focus SVT, fun car to drive but sure wish they came in an auto, the 6 speed trans gets to be a lot of shifting in any kind of stop and go traffic.

[neohic]

Sell it?!?!?! Not an option. When I'm driving, I'm driving. No fiddling with the radio or eating a sandwich. Only reason I put a cup holder in that truck was for the wife.

 

All comes back to wanting ti shift through the gears.

[johnj92131]

Both the Renix and the H.O. share the same cam from what I can find.  Difference is in the H.O. engine the cam is advanced about 8 degrees from the Renix.  This means the Renix engine is tuned for more low end torque, while the H.O. engine is tuned for more horsepower at the higher rpm range.  The smaller Renix throttle is also tuned for low end torque as is the Renix head.  Don't forget that the real drivers were:  1) Emissions requirements.  2) Common parts source requirements (Chrysler in house vs imported Renault).

 

One more indicator of the better low end torque with the Renix?  The factory also changed the 4th gear in the AW4 transmission from .705 to .75 when it moved from Renix to H.O.  That is about the same as changing the final drive from 3.55 to 3.73  Interestingly, Toyota continued to use the same .705 4th gear in its version of the AW4 till the end of the transmissions production life.