My 89 Bronco II Choptop project...

[lil_Blue_Ford]

Thinking about doing the 4.0 too...i have 80,000 on my 2.9 though and am wondering if it would be worth all the work? What do you think?

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The older trucks are where it gets ugly. I know because I tried going down that road. My 88 Eddie Bauer had a 2.9 that ate a valve around 110k miles and I had the "bright" idea at the time of swapping in a 4.0 to replace the "ticking time bomb." Well... Fitting it in and bolting it up wasn't much of an issue. Wiring it up to work, was. I was not able to come up with good wiring diagrams for my truck and for the harness I had and I was not able to get an extra set of hands to help me trace stuff. Arguably, I was also a bit more inexperienced with working in vehicle harnesses. Long story short, it sat uncompleted for a long time.

Putting the 4.0 in an 89 or newer turns out to be a LOT easier, especially if you can get a donor harness from an early 90's Ranger. I only had to splice a handful of wires and I was actually able to build an adapter plug set with ease. So I yanked the 4.0 out of the 88, and put it in my 89, where I needed it. The 2.9 from the 89 is getting some mods (headers, free floating rocker arm assembly, port matching, MAF, etc) and going in the 88, for simplicity sake. I don't plan to do any substantial lifting to my 88, it's mostly going to be a slightly modified toy to run around town in, so I have no need for any more power that a somewhat modified 2.9 will put out, so it works for me.

Now, that said, if you really want to do the swap in your 86 and don't want to have to splice every wire in the harness on the drivers side, there is another potential solution. It involves pulling the dash, but it can be done. The solution is to either swap the entire dash and wiring harness out of an 89-92 RBV, or to pull the dash apart and swap just the dash wiring harness. This gives you the correct plugs (if you take the dash harness from the donor truck with the 4.0), or a nearly correct set of plugs. It's more work than I had to do on my choptop, but for a lifted truck like yours (which sounds pretty similar to my choptop), IMHO, it's well worth it. To get more performance out of your truck, your other options are to mod the 2.9, change the gear ratio to something deeper (4.88 or 5.13), or to do a 5.0 swap (easiest for the older trucks without getting into major wiring is to go with a carbed motor).

 

[Harley]

The older trucks are where it gets ugly. I know because I tried going down that road. My 88 Eddie Bauer had a 2.9 that ate a valve around 110k miles and I had the "bright" idea at the time of swapping in a 4.0 to replace the "ticking time bomb." Well... Fitting it in and bolting it up wasn't much of an issue. Wiring it up to work, was. I was not able to come up with good wiring diagrams for my truck and for the harness I had and I was not able to get an extra set of hands to help me trace stuff. Arguably, I was also a bit more inexperienced with working in vehicle harnesses. Long story short, it sat uncompleted for a long time.

Putting the 4.0 in an 89 or newer turns out to be a LOT easier, especially if you can get a donor harness from an early 90's Ranger. I only had to splice a handful of wires and I was actually able to build an adapter plug set with ease. So I yanked the 4.0 out of the 88, and put it in my 89, where I needed it. The 2.9 from the 89 is getting some mods (headers, free floating rocker arm assembly, port matching, MAF, etc) and going in the 88, for simplicity sake. I don't plan to do any substantial lifting to my 88, it's mostly going to be a slightly modified toy to run around town in, so I have no need for any more power that a somewhat modified 2.9 will put out, so it works for me.

Now, that said, if you really want to do the swap in your 86 and don't want to have to splice every wire in the harness on the drivers side, there is another potential solution. It involves pulling the dash, but it can be done. The solution is to either swap the entire dash and wiring harness out of an 89-92 RBV, or to pull the dash apart and swap just the dash wiring harness. This gives you the correct plugs (if you take the dash harness from the donor truck with the 4.0), or a nearly correct set of plugs. It's more work than I had to do on my choptop, but for a lifted truck like yours (which sounds pretty similar to my choptop), IMHO, it's well worth it. To get more performance out of your truck, your other options are to mod the 2.9, change the gear ratio to something deeper (4.88 or 5.13), or to do a 5.0 swap (easiest for the older trucks without getting into major wiring is to go with a carbed motor).

Yea,thats my thoughts too...i might just get a vehicle to tow my trailer instead of worrying about getting the bigger engine for mine..i dont mund the 2.9 really...it runs great with the 4.10s and 33s. ..i have a new 8.8 rear end with a LS and 4.56s ready to go in and am hoping to get a little more out of it. Its fine once its moving but the clutch takes a beating right now with the 35s...thanks for the reply, always good to ask someone who's been down that road...lol

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[lil_Blue_Ford]

Yea,thats my thoughts too...i might just get a vehicle to tow my trailer instead of worrying about getting the bigger engine for mine..i dont mund the 2.9 really...it runs great with the 4.10s and 33s. ..i have a new 8.8 rear end with a LS and 4.56s ready to go in and am hoping to get a little more out of it. Its fine once its moving but the clutch takes a beating right now with the 35s...thanks for the reply, always good to ask someone who's been down that road...lol

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I have a vehicle I can use to tow my choptop if I want to take it out and play, but I had built the truck with the intention of it being a streetable mild wheeler. Interestingly enough, with the FM-146 trans, it would take off and go without really beating on it for first through third. Fourth was where it fell flat on it's face. Boom. No power. If you beat on it in fourth, it would get up to highway speed and stay there but overdrive was about useless. It was ok like that for around town, but it sucked on the highway. I started seriously kicking around the idea of doing a 4.0 swap after doing a 200 mile run on the highway. That was kind of the last straw.

It seemed to be ok when I ran 33" tires on it, but after upgrading to a D-35 front and putting the 35's on, it started dogging too much to be very enjoyable. With the 4.0, it runs really strong in first through third, and pulls pretty good through fourth. Overdrive has become useful and I can now use cruise control. I haven't done any long highway runs yet since the swap, but the one road I've started running on lately has a several mile stretch with a 55 mph speed limit and I've been known to cruise it in O/D now that I can. I've been going that way since before the 4.0 swap, so it was a real thrill to run it with the 4.0 and see just what a difference it made.

 

[Harley]

Yep...4th is weak and 5th is useless...lol. i hope the 456s will be enough to make a difference.

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[lil_Blue_Ford]

So the 4.0L was nice while it lasted... despite porting the heads and doing new top end gaskets with a 180* thermostat and all, something popped and it's burning coolant. So it gets parked until I can either find a replacement 4.0 or rebuild a 4.0, which will hopefully happen sometime next year. It's always something. Apparently this truck does not like the engines I've been running in it.

 

[lil_Blue_Ford]

Apparently I’m way behind on updates to this thread… standby…

 

[sgtsandman]

 

[85_Ranger4x4]

 

[lil_Blue_Ford]

You guys are being a little dramatic…

 

[lil_Blue_Ford]

I happened to wonder if I had a build thread on here for this and a quick search and here we are. Unfortunately way behind. So now I have to go back and pick up where I left off. Unfortunately I haven’t had time to do anything about that yet. But I wanted to bring it back to the top of the stack so I could find it easier to get this updated. A lot has happened to this rig since my last update. A lot is currently happening. And I’m currently a little salty because the AC system is literally all new and I still don’t have working AC…

 

[Terrys87]

I have seen you mention Choptop quite a bit and just come across this. The last 3-4 pages the pictures are not coming up. Sounds like you have a ton of work involved in it. Great job from what I have seen or read. I suggest keeping a thread on it. I refer to mine for what I did int he past, what parts worked or did not work and a few times where I bought parts and did not remember where. You can take a trip down memory lane. It kind of hard when you get a project done to remember what all was involved. A project done looks like it was easy in a lot of ways until you have been down that road.I subscribed to your youtube channel.

 

[lil_Blue_Ford]

I have seen you mention Choptop quite a bit and just come across this. The last 3-4 pages the pictures are not coming up. Sounds like you have a ton of work involved in it. Great job from what I have seen or read. I suggest keeping a thread on it. I refer to mine for what I did int he past, what parts worked or did not work and a few times where I bought parts and did not remember where. You can take a trip down memory lane. It kind of hard when you get a project done to remember what all was involved. A project done looks like it was easy in a lot of ways until you have been down that road.I subscribed to your youtube channel.

Yeah, I need to read back through, fix any dead pictures after I find them and find where I need to start my updates. Gonna be a bit of a process. I was going to at some point start over with my recollection of things but then I decided to see if I already had a thread. Some pictures might be on my desktop computer which I’ll need to unbury, which is why I’ve been waiting to start on this, but now finding this thread again I might not need into that computer just yet. So we shall see.

Thanks for subscribing! Lot of my videos prior to now weren’t all that great but I think they are getting better. Actually my Choptop introduction video has terrible audio but that picks up roughly where this thread stops…