Best Engine Swap?
- Thread starter kohldad
- Start date
trust
PITA
- City
- White Rock
- State
- NM
I'm facing the same quandry myself, low miles, tight 258 but it wants efi and I am doing the same if then analysis you are. I'm thinking right now of a 4.0 head and factory efi but haven't found the stuff yet. But, I've been told its easier to just do a complete motor. Mine indecision is exacerbated by the fact that I JUST finished installing a new 999tf. I should have ( I think) gone 4.0/AW4 but the cost and rebuild cost was to high plus my 258 only has 80k on it
So, I'm VERY interested in what you decide and how you choose the direction you ultimately take
So, I'm VERY interested in what you decide and how you choose the direction you ultimately take
mssldn said:
I agree, OBD1 is the way to go, at least for my ability and technology at hand. I spent weeks splicing a 94 OEM Wrangler Harness into my CJ bulkhead. Grant it looks factory, but should I do it again, I will save for buying a custom built harness from Hesco. The input and threads from cjoffroad where important reference.
drscanman said:
I have been watching this posting and based on my experience, a lot of good information has been posted. I did the 4.0 HO/AW4 swap eight years ago before the cjoffroad.com site existed. There was plentiful information on the web then about the 4.0 swap but none on the AW4 side of things. I was lucky to find a 92 XJ with 62k miles that was totaled, which I salvaged out. I did not even know about OBDI versus OBDII issues until reading cjoffroad.com.
I agree about the Hesco wiring advice but the last I knew, it did not accommodate the AW4. You might want to check that out. Other things you need to be aware of are that the AW4 is about 5” longer than the T4/5 and the 999. (I can not find what your current tranny is.) This means accommodating in some way that the stock t/c linkage will be 5” back. I ended up modifying a Currie twin stick. While you can use the stock skid plate modified, you will not realize the clearance gains until you have a custom skid plate.
You will have to fabricate transmission cooler lines and have a transmission cooler. I placed a cooler in front of the radiator and then eventually put in a three-row radiator with transmission line connectors and now use both. If I had it to do over again, I would buy a cooler with fan motor and place in the area under the battery tray and eliminate the long lines, etc.
Another item that took a lot of time was the transmission shifter. Nobody that made custom automatic shifters at that time, such as Lockar, could tell me if it would work on an AW4. They would just say buy it and try it. I do not know if this has changed or not. I ended up building a custom console that accommodated the XJ shifter and linkage. This took about three versions over a couple of years to get one that looked appropriate.
I have been very happy with this swap/conversion once I got all the issues fixed. I took me about a year to get it working the way I wanted but answers to most of my issues are now on cjoffroad.com. I am curious to know why Novak was critical and I will check out their web site.
On the 4.0 part of the swap from an XJ, there are a few other issues, which are well covered at cjoffroad.com.
Later, Ken
ibscrmbln said:
As a follow up, the following is what is found on the Novak website:
[I]“The AW4 is a light to medium-duty transmission. Ours, our callers' and customers' experiences with the AW4 are less than stellar. They have a tendency to generate excessive amounts of heat, and are known for unnecessarily consuming more engine power than some other automatics. The shift points in the AW4 feel odd, and the spotty engagement of the lockup torque converter is idiosyncratic.”[/I]
I can not disagree with any of this but this is what I was referring to in my 01/11/08 post, “It took me about a year to get it working the way I wanted…”
The excessive amount of heat and the power loss comes when the torque converter is unlocked. During that post swap year, I was fortunate to find a link on the NAXJA forum to a website that detailed how to wire the shift solenoids and torque converter so that the driver could control the shift points and the locking/unlocking of the torque converter. It only included first and second gear, I use the AW4 shifter for third and fourth. This web article is no longer available but there is now a product that can be purchased to accomplish the same: http://www.awshifting.com/ and here is an article on it’s use: http://www.stu-offroad.com/engine/awshift/awshift-4.htm
Later, Ken
- City
- Dexter
- State
- MI
ibscrmbln said:
There's an article on buying high mileage Jeeps in JP this month where they state that the AW4 is a solid tranny that they liked.
I still think that it's the ideal DD/weekend warrior setup with the 4.0 and the awshifting unit that does the auto/manual operation... I'm planning on doing that in the future DD Scrambler build I'll get to one day
There's a very cool crawl box you can build out of a 231 that will then bolt to a D300 and serve as the adaptor, it's on Pirate somewhere... I thought that would be great with the wheelbase in the Scrambler.
ebertf
Active member
- City
- Soldotna
- State
- AK
Thinking about a 4BT myself care to expound on your experience?
- City
- Dexter
- State
- MI