The best engine swap? The ultimate Question!

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May 11, 2005
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OKLAHOMA cITY
All right,
It is the time for me to make a decision on a new engine for my 91' with the 3fe engine.
But what to do?
What is the humble opinion of the masses here.

My criteria are these in order of importance.

1. dependable
1.5 as good gas mileage as possible
2. as affordable a swap as possible (I'm just a poor fireman)
3. as easy a swap os possible (I'm just a poor DUMB fireman)
4. prefer a toyota

So, thats easy enough isn't it?

Look forward to the input.

Thanks
Kent
 
Engine Swap, '91 LC; Convert to 5 spd ?

Hi livelarg,

I just finished a swap of a Toyota 12HT w/5 spd into an '86 FJ60.
This was an expensive, time consuming, and ultra enjoyable job !

The sound and rumble of the 12HT, the unstoppable torque, and the simplicity / reliability of this diesel makes this a top choice if you've the time, money, and inclination.

Now then - it is my understanding that the 3FE is a very solid and well designed engine. You will presently have an automatic.

Have you considered this: Convert your existing drive train to the H55F 5 speed and change the final drive to the FJ60 gear ratio ?

Your post indicates the larger tires, so maybe changing the final drive ratio is not necessary for good highway RPM. While the engine is out you could have it rebuilt / serviced.

If economy and efficiency of time and money is your concern you probably ought to crunch the numbers on this H55F conversion. The information to do this you will find right here at IH8MUD.

I had to roll over part of my IRA plan into a !2HT plan to do my job. Good Luck.
 
Man, the 12HT swap would be awesome, except for 3 problems with tha engine choice. 1) I don't have that kind of dough to spend 2)not enough time or space to do that kind of swap 3) not enough knowledge for that kind of swap, and it would be WAY expensive to have someone else do the swap for me.

But I sure would like to see pics of your swap!

Thanks
Kent
 
Something to consider:

NONE of the engine swaps are a realistic option from a purely MPG standpoint for most people. You will have to drive so many miles to make it worth the swap, most will never make the money for the swap back in saved fuel.

What is it that the 3FE isn't doing for you? Other than the poor MPG, rebuilding the 3FE you already have might be the best option. Very reliable engine, lots of torque, you already own it, it's a Toyota, no wiring/plumbing/exhaust/transmission/size/motor mount/etc/etc issues to deal with. An early 1FZ-FE might be easy, but for the cost of the motor, and the equally poor mileage, you might not see much benefit over the 3FE for that swap.

Keep the 3FE, beef it up as much as you can from a performance standpoint, and enjoy another 300K miles.
 
Keep the 3FE, beef it up as much as you can from a performance standpoint, and enjoy another 300K miles.

x2. Just have Robbie "massage" it. :D

Join the 3FE Yahoo! group, several 3FE owners who post here are members over there as well (like myself, CJF, Jon Held, and many others). Like 'Mud and LC's, there is a HUGE wealth of 3FE-specific info over there.
 
I'm biased- see sig line :)

Who is gong to do it? You? How competent are you with doing so? What is my time frame for doing it? If I do it, do I have the required tools? These are questions that you have to ask yourself, no reply is needed unless you want to.

Putting in another 3FE will be the path of least resistance. Your mileage will still suffer though. Only a diesel will improve that.

To meet all of your requirements, sell your 91 and buy a diesel Cruiser, whether it's been converted or not.

Do a lot of searching here- lots of good info.

If you have specific ??s for me, let me know.
 
The best way to swap out a 3FE is a '93+. :D
 
So how do you get to the 3FE group again? I cannot find that guy?

I love my 3FE. The PO did a rebuild on it and it is running great. It's not the sexiest, but I can turn her on easy enough every time I try...my engine that is.
 
Spending $5k on a 1FZ-FE engine swap just doesn't make sense when Craigslist is loaded with 93+ 80s for about the same money with the engine already in it. Maybe if your truck is loaded up with other fun toys, but even then, you might start looking for a 93+ locked 80 and swap over all your goodies.
 
I am just completing a GM 6.2 diesel conversion in my 94, hope to be driving it in the next week or two. I will say that from my research it is probably the cheapest swap out there. Everything is available for the swap (mounts, trans adapters, etc). The engines are easy to find, parts and rebuilds are inexpensive. You can even use your Toyota trans (which I would do with a 91). With that said, it is still not cheap. I haven't tallied everything up yet but I am guessing it is going to be in the $7,000 range. You can buy a half cut for almost that much which I would probably do if I were to do it again. You can probably rebuild your engine and trans for that and not have to go through the hassle and down time of a conversion.
I converted mine because I wanted to run WVO and wanted something unique. I have really enjoyed doing it, but it has been 3 months now and I am ready to get it finished and move on to something else.
But, if you are like me and enjoy doing it, have the time, something else to drive while converting and something that very few others have then just forget all the naysayers and do it.
 
No engine swap is going to be easy. If you are not committed to it being a serious project, than just rebuild the 3fe...that is not that hard. If you change your mind and want to do a serious swap...put a cummins 4bta in it.
 
Same problem...

Okay, so I am in exactly the same position as "livrlarg", I too have a 1991 FJ80 with a 3FE. Mine has 285k miles on it and I am trying to figure out what to do when it finally gives up.

All the good things said about the 3FE are true; very reliable, starts right up, runs forever.

The bad is that it has no high speed torque, and I am lucky to get 11MPG. I could settle for either one of those, but not both. Give me some passing power and highway hill climbing power, or give me more gas mileage.

I had thought that maybe a diesel conversion would be great, but it does sound pretty expensive.

So if I just had the 3FE rebuilt, is there anything that can be done to kick this thing up a bit? I haven't wanted to drive this tired old one a lot harder for fear it would just break. But with a new rebuild, maybe a turbo or something would make sense?

Any thoughts?

This is not a case of wanting to swap just for the heck of it, this engine is going to eventually wear out and I will need to replace it with something. Either the same engine rebuilt, a V8 gas, a diesel, or something?

Ideally:

1) Low cost replacement
2) Much more passing and highway climbing power
3) better gas mileage (18mpg?)
4) Similar reliability

A diesel would be very attractive in every respect but #1. The only way it probably makes sense is if I got a wicked deal on a used one in good shape, like from a wreck salvage or something. Pig in a poke that, hard to know what kind of shape it would be in. How hard would it be to do a diesel engine rebuild at home?

A V8 gas would be a pretty good option. Might even end up giving better gas mileage if it didn't have to downshift two gears every time it climbs a mole hill.

Rebuilding the existing engine might give me a gain in #2 and #3 if this one is not performing up to its potential due to age, but I've read the 1991 reviews of th is vehicle reporting how gutless it was (is). With a turbo, or some sort of boost to the EFI?

Hummmmmmmmmmm??????????

Going to have to do something. Tired of having 1200cc VWs pass me.

Cheers!
 
Okay, so I am in exactly the same position as "livrlarg", I too have a 1991 FJ80 with a 3FE. Mine has 285k miles on it and I am trying to figure out what to do when it finally gives up.


We are in the same boat. My engine is still pretty good, but with 250K of hard abuse (off road-towing-daily city driving) it is starting to wear down. You can always see where i park because of the black-sooty wet exhaust blasting on to the driveway.

What are the specs on the on the cummins 4bt engine anyway? man, that would be sweet.

Kent
 
Cheapest way is to rebuild the 3FE, dependability, durability, and longevity are their. Power is their as well with 4.88 R&P's. https://forum.ih8mud.com/80-series-tech/55383-since-3fe-slow-why-no-aftermarket-support.html

Chevy Lt1 or a Ford 5.0 donor car for cheap then rip out what you need. Maybe you will get better mileage and maybe you won't but the power will be their. (the engines might need rebuilds as well) The 4BT would be nice but the engines are $$$$. I wish Toyota made a 4.0l+ SOHC engine like the smaller 22RE but instead they developed the 1FZ.
 
A bit more help???

Cheapest way is to rebuild the 3FE, dependability, durability, and longevity are their. Power is their as well with 4.88 R&P's. https://forum.ih8mud.com/80-series-tech/55383-since-3fe-slow-why-no-aftermarket-support.html

Chevy Lt1 or a Ford 5.0 donor car for cheap then rip out what you need. Maybe you will get better mileage and maybe you won't but the power will be their. (the engines might need rebuilds as well) The 4BT would be nice but the engines are $$$$. I wish Toyota made a 4.0l+ SOHC engine like the smaller 22RE but instead they developed the 1FZ.

Okay the link is an interesting read, but there are more opinions than posts in that thread, some saying their 3FE is a rocket ship, others saying it isn't worth working on, others saying there are obvious things to do to improve it. But there is an awful lot of jargon without a lot of explanation.

Forgive my ignorance, but I haven't been studying this that long yet. What is a 4.88 R&P? Saw it mentioned in a couple of posts from that thread, but no explanation.

If this 3FE were any slower going up a grade it'd have to "down shift" into reverse to keep the RPMs up! I have a new factory CAT on it and had a complete tuneup. That made VERY SMALL improvement. It sometimes has to downshift to 2nd gear on a 55mph country road to climb a grade when the slowest granny on the road is piling up behind me. And 11 to 12 mpg is tops.

What (specifically, and with a little explanation please) can be done to either get more HP, or more fuel efficiency, or preferably both, out of this engine?
 
4.88 R&P is ring and pinion in the third members, the differentials in the axles. The power and torque delivered to the ground is multiplied by the new ratio (4.88) instead of (4.11 < the stock R&P ratio).
 
its lasted that long its time to return the favor!

maybe a rebuilt 3fe will yield more power? Than your already proved its self 250-350k wore out poo poo on it cause it dont have no power!!!! and it aint cool!, motor already has, since the cylender walls could be letting pressure and oil by, injectors and intake could be clogged, carbon build up on the valves. EGR stopped up??


Allot has happened in what we call "high miles" allot of gas (some good quality, some bad quality) has gone through it, allot of wear put on it......

For crying out loud stop this. :mad:


Q:":hhmm: My motor has gone 300k it has no power, the cool kids dont like it, but still runs, what can I do except repower it? :hhmm:"

A: spend way more money converting it to a less reliable, having to purchase unit.:doh:



The best motor for it?...........is already in it!
 
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Speed, Power and Mileage are all matters of pay now or latter. The cruiser is still drivable so you have some time. I would look at what you use it for and what is the most important thing you want out of it. If you tow or drive a lot of steap grades power would be nice and just about all options would get you this. If it is driven on road mostly, then mileage may be most important and at $3 a gallion we all want better mileage. The links on the deisel conversion it is a nice swap but for the 4BT you need a 3-4" lift, but you can watch and get the engine from 2-3000 and could still use your transmision. The 12ht would be nice as it is all bolt in but a lot of work and most likely the most expensive but it would be all toyota. The new 5.3 to 6.0 GM engines can be a nice swap and there is lots of info on this and it would give you the most power, if you keep your foot out of it should get you 3-5 mpg improvement and the people that have done this swap seam happy and willing to answer questions if you go this way. I am thinking of the 6.0 for my cruiser, plus you can pre buy a lot of the parts.
 
Okay, so I am in exactly the same position as "livrlarg", I too have a 1991 FJ80 with a 3FE. Mine has 285k miles on it and I am trying to figure out what to do when it finally gives up.

All the good things said about the 3FE are true; very reliable, starts right up, runs forever.

The bad is that it has no high speed torque, and I am lucky to get 11MPG. I could settle for either one of those, but not both. Give me some passing power and highway hill climbing power, or give me more gas mileage.

I had thought that maybe a diesel conversion would be great, but it does sound pretty expensive.

So if I just had the 3FE rebuilt, is there anything that can be done to kick this thing up a bit? I haven't wanted to drive this tired old one a lot harder for fear it would just break. But with a new rebuild, maybe a turbo or something would make sense?

Any thoughts?

This is not a case of wanting to swap just for the heck of it, this engine is going to eventually wear out and I will need to replace it with something. Either the same engine rebuilt, a V8 gas, a diesel, or something?

Ideally:

1) Low cost replacement
2) Much more passing and highway climbing power
3) better gas mileage (18mpg?)
4) Similar reliability

A diesel would be very attractive in every respect but #1. The only way it probably makes sense is if I got a wicked deal on a used one in good shape, like from a wreck salvage or something. Pig in a poke that, hard to know what kind of shape it would be in. How hard would it be to do a diesel engine rebuild at home?

A V8 gas would be a pretty good option. Might even end up giving better gas mileage if it didn't have to downshift two gears every time it climbs a mole hill.

Rebuilding the existing engine might give me a gain in #2 and #3 if this one is not performing up to its potential due to age, but I've read the 1991 reviews of th is vehicle reporting how gutless it was (is). With a turbo, or some sort of boost to the EFI?

Hummmmmmmmmmm??????????

Going to have to do something. Tired of having 1200cc VWs pass me.

Cheers!

I was in a similar situation with my old 84 FJ60. Even with the power mods I made (converted to GM EFI, high flow cat, exhaust, and intake) it still was a dog on the hills and lousy for towing.

The easiest solution is sell it for a 93+ with the 1FZ-FE. It cost me about $4000 plus the proceeds from the sale of the FJ60, but you get an immediate turn-key rig ready to go. The FZJ80s are now getting cheap enough that it didn't make sense to me to dump any more money into my FJ60, plus you likely get a lower mileage rig, lockers, and the ability for modest towing. Mileage wise, the FZJ80 still gets slightly better mileage than the FJ60 did and has MUCH better highway manners.
 
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