3FE in a fj40. What will be better? (1 Viewer)

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Trollhole

Trollhole

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I'm planning on doing this swap this winter after I rebuild the 3fe that is soon to show up on my doorstep. I have a couple of questions.

I currently get 10mpg on my 2f with a webber 38. Gas milage is terrible at least. And starting in winter is a pain. it also has a 6 to 1 performance header and stock dist. Performance is great on road but not so great off road at crawling speed.

What if any will a 3fe do to help or hinder any of these problems?

I know I'm gaining HP. But is a 3fe better than a 2f in any way other than that?
 
The obvious if FI and its increased efficency, should be much more consistant when it comes to running rich or lean than your old weber........... with a rebuilt 3FE I would imagine the mpg would be some where around 16. And my 62 has no trouble starting in cold It cranked right up last january when I was camping high up in the App. mountains with the temp outside -10 F. It also should handle low idle speeds better than the carb. you say how matts 62 did at Tellico........

Most importantly the Cool factory is way up there!!!!!!! and you will be keeping it all Toyota

Also talk to Dearborn he loves the 3FE and knows how to tweak them just right ;)
 
A well tuned carb will always be able to under idle EFI because EFI has to be running a certain speed to fire. Advantage, run upside down. Disadvantage, less low speed torqe for the 3fe (shorter strock). A good option is to rebuild the 2F block and put the 3fe head and intake EFI stuff on it, given you dont' have dome topped pistons.

A webber can be made to run well, I get 15 mpg in my SO cruiser on 35s with an F and vacuum advance points dist. Runs pretty well off camber with a lowered float bowl and will bog down to 200 rpm and keep on chugging. Much tweeking was involved with jets to get it right for my elevation.

All that said i'm planning to do GM EFI soon I hope, I want to run upside down :) I hate when it stalls at 45 deg unless I got my foot in it.
 
I would not do this with the hopes of getting 16 MPG in a stock 40, let alone one the is modified...


I would do it for better cold weather starting, and off camber operation.


Good luck!


-Steve
 
Trollhole said:
I currently get 10mpg on my 2f with a webber 38. Gas milage is terrible at least. And starting in winter is a pain. it also has a 6 to 1 performance header and stock dist. Performance is great on road but not so great off road at crawling speed.

What if any will a 3fe do to help or hinder any of these problems?

I know I'm gaining HP. But is a 3fe better than a 2f in any way other than that?
Click to expand...

A tight 2F + JimC stock carb should improve your mileage and performance and it would be easier. But if you're going down the 3FE route you should see improved mileage, but no more than what a good running 2F would deliver. Yes you'll have some gain in HP but you'll be losing the low-end torque. On road performance will be good, a 3FE + manual tranny is a good comibation. You'll have no more winter starting problems. No cold stumbling for 2-3 miles, just fire it up and go.

I've had a 3FE in my 60 for a good 100k miles now. Mileage has been around 14-15 mpg with an H42 + 4.11's + 33's. You may find the 3FE to be more sensitive to tire and gearing combinations than the 2F, and I think this is because of the reduced low-end torque. The 3FE likes to run at higher rpm than the 2F.
 
Have you thought about a propane kit - very popular down under here in NZ. Good cold starting & running, and will run at any angle. Pretty simple and relatively cheap to fit & gas costs about 60% the price of petrol (here at least...)
 
Trollhole said:
I'm planning on doing this swap this winter after I rebuild the 3fe that is soon to show up on my doorstep. I have a couple of questions.

I currently get 10mpg on my 2f with a webber 38. Gas milage is terrible at least. And starting in winter is a pain. it also has a 6 to 1 performance header and stock dist. Performance is great on road but not so great off road at crawling speed.

What if any will a 3fe do to help or hinder any of these problems?

I know I'm gaining HP. But is a 3fe better than a 2f in any way other than that?
Click to expand...

This is just my opinion, so take it as that.

The 3FE is a good motor. EFI from the factory, decent torque, etc.
However, the wiring is going to be insane.

You're going to be better off tuning the weber, or (preferably) throwing the weber in the trash and putting a rebuilt and desmogged Aisin carb on the motor.

My experience is that I can run 15-16 mpg CONSISTANTLY with occasional 17-18mpg (on road trips, etc). THat's running an SM420, 35" tires, performance header, performance carb, Non-USA distributor, the works.

IF you're getting 10mpg, and it's not offroading well, you need to look at tuning the carb, adjusting float levels, etc.

All of these thigns will be easier than taking out the 2F and putting in a 3FE and WIRING it.
 
Godwin said:
A tight 2F + JimC stock carb should improve your mileage and performance and it would be easier. But if you're going down the 3FE route you should see improved mileage, but no more than what a good running 2F would deliver. Yes you'll have some gain in HP but you'll be losing the low-end torque. On road performance will be good, a 3FE + manual tranny is a good comibation. You'll have no more winter starting problems. No cold stumbling for 2-3 miles, just fire it up and go.

I've had a 3FE in my 60 for a good 100k miles now. Mileage has been around 14-15 mpg with an H42 + 4.11's + 33's. You may find the 3FE to be more sensitive to tire and gearing combinations than the 2F, and I think this is because of the reduced low-end torque. The 3FE likes to run at higher rpm than the 2F.
Click to expand...

I'd be VERY suprised if a stock 3FE's HP numbers were any better than a well built 2F's numbers..
 
Tigerstripe40 said:
You're going to be better off tuning the weber, or (preferably) throwing the weber in the trash and putting a rebuilt and desmogged Aisin carb on the motor.

My experience is that I can run 15-16 mpg CONSISTANTLY with occasional 17-18mpg (on road trips, etc). THat's running an SM420, 35" tires, performance header, performance carb, Non-USA distributor, the works.

IF you're getting 10mpg, and it's not offroading well, you need to look at tuning the carb, adjusting float levels, etc.

All of these thigns will be easier than taking out the 2F and putting in a 3FE and WIRING it.
Click to expand...

Agree. I'm running similar setup in my 40, rebuilt 2F, JimC carb, header, FJ60 distributor, H41, 35's, while I'm not seeing the mileage of TS40 I do get a consistent 14-15 mpg. Rewiring an FJ60 with an FJ62 harness was as simple as pulling out the old and sticking in the new, I would have no idea how to patch in the necessary wiring to run a 3FE into a 40. Rebuilding a 2F is, by far, the easier route.

Don't swap in a 3FE in an attempt to gain HP and increased mileage, you can accomplish the same thing with a good 2F rebuild. But if you have other goals, such as wanting Toyota EFI in your 40 or something such as that, then the 3FE swap may be the way to go. The 3FE is a good engine just not a pancea for HP and improved mileage.
 
Tigerstripe40 said:
This is just my opinion, so take it as that.

The 3FE is a good motor. EFI from the factory, decent torque, etc.
However, the wiring is going to be insane.

You're going to be better off tuning the weber, or (preferably) throwing the weber in the trash and putting a rebuilt and desmogged Aisin carb on the motor.

My experience is that I can run 15-16 mpg CONSISTANTLY with occasional 17-18mpg (on road trips, etc). THat's running an SM420, 35" tires, performance header, performance carb, Non-USA distributor, the works.

IF you're getting 10mpg, and it's not offroading well, you need to look at tuning the carb, adjusting float levels, etc.

All of these thigns will be easier than taking out the 2F and putting in a 3FE and WIRING it.
Click to expand...


Well I'm a little heavier on the foot. I'm finding it hard to believe a nice built 3fe wouldn't have more HP over a 2f. And if people are getting 15-17 in a 62 with a 3fe I would assume in a 40 it would be even better.

Is there anyone out there who has done this swap? Comments.

And even if the 3fe proves no better on economy and hp. Then no big deal. On the wiring side I like a challenge and I have a nice 2f in my cruiser working well. I'm going to take my time on the swap and do it right. Plus I'll do a nice write-up on it for others as well as dino numbers of old and new.
 
So far from what I can tell a 2f has 135hp with 210lbs tourqueand a 3fe has 155hp with 220 lbs of torque.


And a 3fe weighs 100 pounds lighter.

SOmething is not right here. More hp more torque and less weight. I cannot see why I wouldn't get better performance and fuel economy.
 
shorter stroke and higher compression.

3FE's tend to run hotter than 2F's as well.

Look at what RPM's those numbers came from.
 
Trollhole said:
Okay. Who here has a 3fe in a 40? I would like some personal feed back if possible. Anybody?
Click to expand...

3FJ40 has completed most of the swap.

If you really get into this swap you should join the 3FE list at http://autos.groups.yahoo.com/group/3FE/, cuz this is your best source for 3FE specific information.
 
Godwin said:
3FJ40 has completed most of the swap.

If you really get into this swap you should join the 3FE list at http://autos.groups.yahoo.com/group/3FE/, cuz this is your best source for 3FE specific information.
Click to expand...

It will be completed SOON! we hope... Darn kids!

My bro got the idea after test driving a 3fe 40 in Denver some time back. A little searching on the 3fe list and he came up with a Donor. His poor 2F had horrible compression and was on its last legs-because of the PO (i always say that when something goes wrong on my/his LCs-I hope I never buy one new-what would I say then?).

Anyway, good power and responsive. Basically a modernized 40-but defintely an increase in power-I can't really explain what power, it was just the "feel" ya know (according to him). Problems you will run into are manifold for the exhaust and the intake being VERY tight to the Brake booster (am I righto Pskhaat?). Workable solutions exist though. I'll wait for him to chime in-if he's lurking.
 
Godwin said:
3FJ40 has completed most of the swap.

If you really get into this swap you should join the 3FE list at http://autos.groups.yahoo.com/group/3FE/, cuz this is your best source for 3FE specific information.
Click to expand...


Funny I joined it about an hr after I posted that last message.
 
im looking into the same kinda swap in my 40, but what about cooling, is the 40 radiator, big enough for the 3fe, i know the 62 radiator is bigger. i have a rod throttle linkage on my 40 what does the 3fe have?
 
FJ40onNOS said:
im looking into the same kinda swap in my 40, but what about cooling, is the 40 radiator, big enough for the 3fe, i know the 62 radiator is bigger. i have a rod throttle linkage on my 40 what does the 3fe have?
Click to expand...


FJ40 rad should be ok. FJ40 rad cools a 2F just fine, FJ60 rad cools a 2F just fine, FJ60 rad cools a 3FE just fine, therefore FJ40 will cool a 3FE just fine.

The fan sits lower on a 3FE than on a 2F so you'll more than likely have to make a little adjustment to the fan shroud. A working fan clutch is key to keeping the 3FE temps in check.
 
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