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85 Bronco II engine swap. what are my opitions?

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Old 10-26-2010, 06:29 PM
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85 Bronco II engine swap. what are my opitions?

MY first post on this forum and don't know much about 4x4. I bought a 85 bronco II for $500 for offroading and maybe some daily driving as well. Body is in good condition but the engine is running rough. Currently looking to do an engine swap. What are my options? A newer 2.9 V6 with FI or 302 V8 FI? What are the pros and cons with different engines that fits this truck? Someone is selling a 302 thats been pulled from a 91 mustang with 77k miles for $250. Is that a good deal? I'm new to the offroading sport. Any friendly advice would be a appreicated? Thanks in advance!

Is there any way for me to upload pictures and not from a URL?
 
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Old 10-26-2010, 07:09 PM
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Easiest thing to do is swap in a 4.0 from a Explorer,..........lots more power than the 2.8 or 2.9, it bolts right up to any trans the 2.8/2.9 does, Just grab the ENTIRE wire harness and ECU from the Explorer.

302 swaps are easy too, but involve lots of aftermarket/salvage yard parts to make work, not hard, just a little involved.
 
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Old 10-28-2010, 03:46 AM
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Well, i have never swapped a motor in one of these, i think if you put a heavyer engine like a v-8, then the trans to go with it...then transfer case and other things...you just added like 1,000 pounds extra to your front end and messed up the factory weight distribution. I like keeping things stock i guess....there is a reason things are made the way they are. Also, the 4.0 does have more HP, but a lot less TQ. TQ is what you need to off-road...aka climbing things, pulling you through sticky stuff, hauling stuff. Also, there is a lot of information on a website called therangerstation.com about this, and articles about the pros and cons of each engine. And about the power issue with the 2.9, I have my stock 2.9, rebuilt, and modified a little. If you look a couple of threads down to where i introduced myself, i listed a lot of things i did to my truck. I think the most importiant thing is reliabuillity, tire choice, and your gear ratio. But, that is just my opinion
 
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Old 10-28-2010, 08:53 AM
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There were a lot of changes to the little RBV's over the years.

The 2.8's were carbed. They were a high rpm engine used in the Mustang and Capri for road racing and had a lot of aftermarket go fast stuff. Comon problems were the electronic feedback carb and distributor. Some replace with the earlier Dura Spark dist. and std. 2bl carb. Carb's have trouble in some types of Off Roading. I go to Colorado and it is difficult to get a carb to do well on steep rocky climbs with large changes in elevation.

The 2.9 was fuel injected and had more low end torque. I really like FI for off road. But it can be a lot of work changing all the eletronics over in your truck. Different fuel pumps, gas tank, fuel lines, in addition to the wiring. Not even sure the dash wiring is the same.

As was said if you are thinking about an earlier model 2.9, a 4.0 might be the way to go instead. The early push rod 4.0 has more power and torque. The BII changed again in 89. I have read that the 89-90 dash is more compatable for the 4.0 wiring. Mid 90's pushrod 4.0's are said to be the best by some.

And the 5.0 is an option folks like to do. But that would be none factory. Just depends on how much of a dd you want to keep it. A carbed 302 would be less work and headaches for your 85. The more stuff you want to keep the more headaches. Like AC, .....ect.

The 3.8 is another option. Basicly it's a 5.0 minus 2 cylinders. This gives you a bit more room under the hood.

If it were me I just look around for a newer RBV with a 2.9 or a 4.0 and use it. The early 90's RBV's with the 4.0 had larger, stronger axles. While you are waiting you could try a duraspark conversion and 2bl non feedback carb.

If this is just a toy and you have the time and place to do the work then have at what ever ya like. Your $1.25. Do what ya want.

You need to post more. Can't remember what the number is but once you reach it you will be able to do more stuff like see folks profile, post pic's, send private messages ect. It's that way to prevent abuses.

Good luck and welcome to the board.
 
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Old 10-28-2010, 10:06 AM
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Originally Posted by mdr617
Well, i have never swapped a motor in one of these, i think if you put a heavyer engine like a v-8, then the trans to go with it...then transfer case and other things...you just added like 1,000 pounds extra to your front end and messed up the factory weight distribution. I like keeping things stock i guess....there is a reason things are made the way they are. Also, the 4.0 does have more HP, but a lot less TQ. TQ is what you need to off-road...aka climbing things, pulling you through sticky stuff, hauling stuff. Also, there is a lot of information on a website called therangerstation.com about this, and articles about the pros and cons of each engine. And about the power issue with the 2.9, I have my stock 2.9, rebuilt, and modified a little. If you look a couple of threads down to where i introduced myself, i listed a lot of things i did to my truck. I think the most importiant thing is reliabuillity, tire choice, and your gear ratio. But, that is just my opinion
Not really, only about 100Lbs. diff in engine weight.
 
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Old 10-28-2010, 10:31 AM
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The worst problem encountered with the V-8 swaps, is being adult enough not to kill yourself with all that power.............I DO NOT RECOMMEND A 302 POWERED B2 OR RANGER FOR A NOVICE OR IMMATURE DRIVER!!!......Bronco IIs have tricky emergency handling as it is, add in all that V-8 power and what it brings to the table, you have a handfull, Rangers with the longer wheelbase are more docile with a 302. As far as front end wear, I have never noticed anything adverse on any of the 302/351w Ranger/B2 swaps we have done, weight difference is negligible.
 
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Old 10-29-2010, 06:47 PM
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Thanks for everyone kindly advice! This will be my toy, but I would like it to be street legal as well. A friend of mine whom works at a shop is going to help me out with the swap. Since this is my first 4x4, I am leaning toward just swapping 4.0 from a explorer since its the eaisest. I want to hit the trails soon. Wrecked explorers are easy to find out here in AZ.

I just have few more newbie questions regarding this swap. What year of explorer should be looking for as a donor vehilce? Early 90's? Someone is selling a 4.0 from a 91 explorer with 80k miles. So I might check it this weekend.

Also, what about the transmission? Should or can I keep current transmission or replace it with one from explorer. Beside the entire wiring harness, what else should take from the donor vehicle? Am I going to encounter any wiring problems? Will there be any emission issues? I just want to be prepare.

Last question regarding tires size. This truck currently has a 4 inch lift kit. I think its sitting on 32 or 33 tires, have to double check tonight. Its has almost no treding left. Front fenders looks to be either custome fabricated or came from another truck. Its extra wide with extra clearence, but rear fender is stock. I can't post a picture up so hard to explain. What tire size do you guys recommend with this set up?

Thanks everyone in advances! sorry for being a offraod noob!
 
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Old 10-29-2010, 07:11 PM
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What trans is in the B2 now?
5spd.......OK
Automatic (C-5) (A4LD?) not very strong.......Neither is the Explorer automatic(needs computer to run), think about going to a Ranger/B2 5spd manual gearbox.

Any good 4.0 from 89-96 Ranger/Explorer will do well.
 
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Old 10-30-2010, 01:06 PM
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IF you go the 4.0L engine, best to use the A4LD tranny that's with the 4.0 engine. Explorer A4ld trannys were built better for the HP and torque of the bigger engine.

BUT they still have the same problem areas like front seal leaks and the OD unit gernading. Also you will need all fuel lines and tank for the EFI system. Best bet is finding a wrecked explorer and get the whole vehicle and start swapping over whats needed. Its all bolt in from any 91 to 94 Explorer.

For a 302 swap, that is more involved and not easy for someone who is just getting their feet wet. The 4.0L swap will be a good learning experance.

Now for me(after getting heckled again that it can't be done) I'm going to install a big 300 I6 from a truck in my B2. Now thats going to be a learning curve stuffing a LONG engine in there!
 
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Old 10-05-2016, 05:06 AM
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Go to Ranger station look up 5.0 Ford engine swaps for Bronco ll. They got a page that shows you how to do it with minor modifications. Can use the transmission in the Bronco II just need to do some changes like bell housing etc. You will have to do some fabricating cause you can't use the factory engine mounts but if you can weld or no some one who can weld it's not a issue. Like I said tho you'll have to do some modifications to fit it in like the AC box in the back on the firewall you'll have to remove or modify to fit the engine. It'll go threw the whole swap step by step tho. I gotta 89' Bronco II and plan on doing the same thing or I'm gonna drop a 7.3l turbo diesel engine in it which will take alot lot more modifications but it'd be worth it if I could find a engine/transmission and transfer case for cheap for it I could mode the drive shafts and fabricate mounts etc the fit it all in. Then build custom fenders around it for the front end.
 
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Old 11-07-2016, 07:51 AM
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Originally Posted by Old93junk
Easiest thing to do is swap in a 4.0 from a Explorer,..........lots more power than the 2.8 or 2.9, it bolts right up to any trans the 2.8/2.9 does, Just grab the ENTIRE wire harness and ECU from the Explorer.

302 swaps are easy too, but involve lots of aftermarket/salvage yard parts to make work, not hard, just a little involved.
Can I put a 300 straight six in a 87 bronco 2 it's a 4.9 out of a f150 89
 
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Old 11-07-2016, 11:21 AM
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Originally Posted by Old93junk
What trans is in the B2 now?
5spd.......OK
Automatic (C-5) (A4LD?) not very strong.......Neither is the Explorer automatic(needs computer to run), think about going to a Ranger/B2 5spd manual gearbox.

Any good 4.0 from 89-96 Ranger/Explorer will do well.
1984 Bronco II came with the C5, 1985/89 Bronco II came with the A4LD (made in France), the worst A/T that Ford ever offered, worse even than the AOD, and that's saying something.
 
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Old 11-07-2016, 05:26 PM
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Originally Posted by NumberDummy
1984 Bronco II came with the C5, 1985/89 Bronco II came with the A4LD (made in France), the worst A/T that Ford ever offered, worse even than the AOD, and that's saying something.

2x on that! 3 A4LD's in 3 years..... Last one the OD unit failed locking up the entire drive line, almost got T-boned due to that... had carnage photos but microsnot made them disappear along with many more photos many years ago.


After some figuring on how to stuff a 300 I6 in the B2, hacking up the firewall and making a doghouse like a van was not to my liking. I got a manual 5 speed to put in instead!
 
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Old 11-07-2016, 05:53 PM
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Originally Posted by Eddiec1564
2x on that! 3 A4LD's in 3 years..... Last one the OD unit failed locking up the entire drive line, almost got T-boned due to that... had carnage photos but microsnot made them disappear along with many more photos many years ago.


After some figuring on how to stuff a 300 I6 in the B2, hacking up the firewall and making a doghouse like a van was not to my liking. I got a manual 5 speed to put in instead!
When I worked at Cerritos Ford (in L/A County) 1985/86, the new car department only sold new Bronco II's and Ranger's with manual transmissions.
 
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Old 11-07-2016, 06:25 PM
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Originally Posted by CurtisBurdick34
Go to Ranger station look up 5.0 Ford engine swaps for Bronco ll. They got a page that shows you how to do it with minor modifications. Can use the transmission in the Bronco II just need to do some changes like bell housing etc. You will have to do some fabricating cause you can't use the factory engine mounts but if you can weld or no some one who can weld it's not a issue. Like I said tho you'll have to do some modifications to fit it in like the AC box in the back on the firewall you'll have to remove or modify to fit the engine. It'll go threw the whole swap step by step tho. I gotta 89' Bronco II and plan on doing the same thing or I'm gonna drop a 7.3l turbo diesel engine in it which will take alot lot more modifications but it'd be worth it if I could find a engine/transmission and transfer case for cheap for it I could mode the drive shafts and fabricate mounts etc the fit it all in. Then build custom fenders around it for the front end.

Welcome to FTE. This thread is 6 years old. If you are going to do a swap and need help, I would suggest starting your own thread here. Also, IMO the 7.3 into BII swap would be a fantastic way to send both the engine and the BII to the scrap yard. Driveshafts, mounts and fenders would be the least of your concerns.

Good luck!
 


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