3FE vs 2F (1 Viewer)

[freepowder]

Revisited the Fourwheeler magazine article that converts an FJ60 to a 3FE.

This thought came up when reading the specs for each engine:

The 2F makes 135hp, 210 fp torque.
The 3FE makes 155hp, 220 fp torque.
The 2F compression ratio is 7.8-1
The 3FE compression ratio is 8.1-1

I wonder what the 2F would make if you raised the compression. Were it equal to the 3FE would the hp figures get closer? Be equal? What if you raised the compression to say 8.8? 9? Yeah, premium gas comes into play but. . . I wonder.

The 3FE FJ60 made 16 mpg I don't consider this to be a cost effective swap. They mentioned 'Cold stumbling starts are a thing of the past,' I've never had that problem with the 2F even with the choke not working.

They say the 3FE, 'the engine has never faltered or lacked for power,' neither has my 2F.

They say, 'Advantages of swapping a 3FE for a 2F include easy starting, a smooth-running engine, perhaps improved mileage, onboard diagnostics if a problem does occur,. . .Toyota dependability, and reliability,' my 2F, starts easy, runs smooth, gets 14 mpg, is de-smogged so my diagnostic computer (my human brain) works fine, and also exhibits Toyota dependability and reliability. Not cost effective I say.

A question: Does raising the compression ratio positively affect performance at high altitiude (>7000') all else being equal?

 

[TS888]

A question: Does raising the compression ratio positively affect performance at high altitiude (>7000') all else being equal?

Simple answer -- yes. At 7,000 feet, your engine output is down about 20% from sea level. Anything you do to increase horsepower will have a corresponding effect at any altitude.

On a relatively low compression engine like a 2f, increasing compression will give a useful gain in horsepower. Combine that with a more "aggressive" cam and you would feel the difference, but probably would not hit the 3FE HP numbers.

The 3FE benefits from the more controlled and equal fuel distribution of the injection system as much as from the higher compression ratio. Plus I think it has a shorter stroke, which benefits HP over torque.

 

[Mark W]

The only positive the 3F has over the 2F is the induction system, Not that the 3F is a bad motor... (it does have some design shortcomings however)... the 2F is just better.

Increasing compression (in the ranges we are dealing with )ALWAYS improved performance and efficiency.


Mark...

 

[Cruiserdrew]

The only positive the 3F has over the 2F is the induction system, Not that the 3F is a bad motor... (it does have some design shortcomings however)... the 2F is just better.

Increasing compression (in the ranges we are dealing with )ALWAYS improved performance and efficiency.


Mark...

Hey Mark-Glad you survived a record Alaskan winter.

What are the shortcomings vs a 2F? I love my 3FE. The 3FE makes better power and torque at all rev ranges and is much smoother. Also the extra 20 HP it makes, is THE critical difference. FJ62 feels peppy, FJ60 feels slo..

Anyway, not arguing, just looking for facts to tuck away for a fireside discussion.

Just for reference, Just got my FJ40 running again with an 85 2F and my FJ60 has a stock and untouched 2F. So I have nothing against 2Fs. I will say this-an 85 2F is WAY smoother running than a 76 2F. And a 3FE is way smoother than later 2Fs.

 

[umpqua]

Yes, please expound. Inquiring minds want to know.

The only positive the 3F has over the 2F is the induction system, Not that the 3F is a bad motor... (it does have some design shortcomings however)... the 2F is just better.

Increasing compression (in the ranges we are dealing with )ALWAYS improved performance and efficiency.


Mark...

 

[elripster]

I just swapped out my 2F for a 3FE. It's the difference between an old carb'd engine vs. a modern fuel injected engine due to better breathing, higher compression, wider torque band, a lot less vacuum lines, easier starting, crisper throttle response... etc...

The 3FE is faster at all speeds. I didn't particularly mind the 2F, but it would have been very expensive to rebuild and then I would still have to get it to pass smog after returning to SoCal. 3FE made the most sense for me since I was in the unique situation of needing to rebuild a 2F and then having to smog one in Cali which is quite hard (and expensive) to do when none of the smog stuff is working.

If saving money is the key, building and wheeling old 4X4 vehicles is going the opposite direction. If improving the vehicle but sticking more to its roots is your goal, the 3FE is a great option.

Only downside, my tendency to cruise faster on the freeway is making me want an H55F all the more. So much for saving dough...

Frank

 

[elripster]

Another nice thing about the 3FE (at least from an 80 series, maybe a 62 as well) is that the alternator is a bit more powerful and I think the power steering pump is as well. The smog pump is not in a place where power steering fluid will leak onto it. 3FE's are easier to work on than 2F's.

Frank

 

[freepowder]

<snip>

If saving money is the key, building and wheeling old 4X4 vehicles is going the opposite direction. If improving the vehicle but sticking more to its roots is your goal, the 3FE is a great option.

<snip>
Frank

I'm not sure about that. A Jeep Rubicon sells new for about $30-40,000. And it's gonna need a lift kit anyway. I figure by the time I get my 60 done I'll have about $20,000 in it. Plus, I know LCs, know what they can and can't do and trust 'em. With a de-smogged 60 if something breaks on the trail I can, have and will diagnose it, fix it and get home, barring rolling it off the mountain or burning it to the ground. But of course that would take out a new vehicle also.

My concern is bang for the buck. I'm thinking I could get a GM TBI kit for $1200 and a 3FE conversion is gonna be a helluva lot more than that. There's also a convenience factor--I'm gonna read the instructions and slap on the TBI but I'm gonna spend a lot of time searching threads on Mud and standing around looking at parts while scratching my head with the 3FE conversion. Combine the two factors and I keep coming up TBI.

 

[elripster]

Well.... I don't think you will be scratching your head all that much with a 3FE swap. If you get one out of an FJ62 it all just fits.

There are parts where the engine control needs to interface with the vehicle for batt, key on power as well as gauges but that is true for both engines.

There are also peripherals like the fuel pumps which you will have to plumb and wire up. I suppose you could get an Fj62 tank but for all the work you can just get a fuel pump and filter from Summit.

I have a big old thread on my 3FE swap you can read to get an idea of what I did with an 80 series. A 62 would have been easier. What you should note from that thread is how many things will be common to any engine swap and see what you think about the difficulty.

With both swaps you will need new accessories. AC lines from the GM will need to be custom. Your alternator wiring will need to be modified and put in loom, PS lines won't line up, etc... Lots of little things.

If power is your goal, well the 3FE will get stomped by any American V8.

Just keep in mind the V8 swap is a lot more than just a TBI kit.

Frank

 

[freepowder]

<snip>

Just keep in mind the V8 swap is a lot more than just a TBI kit.

Frank

You misunderstand me--I don't want to do an engine swap. I'm just thinking about upgrading to fuel injection. When I'm talking about 3FE, It would just be the head and so forth. The TBI would mount on the existing 2F manifold. From what I've seen and heard, the TBI kit is gonna be a lot easier than building a 2FE out of 3FE parts. And a lot more cost effective.

 

[elripster]

Ah, I see, I didn't realize that. You are probably right, quickest route to FI is probably just the TBI upgrade. People rave about the 2FEs though and I can see why. 2F torque with 3FE RPM range has to make for one sweet engine.


Frank

 

[Yspen]

As said above - tbi is easiest and not a bad option.

I ditched my 3F carbed engine for a 2F . What Mark said is true. The 2F is more drivable offroad .
Now in the process of getting all the parts for efi conversion. It is costing me a lot as shipping to Africa is not cheap. If I lived in the US , building a 2F-e would be a nobrainer. The parts are easy to find and relatively cheap.

 

[csd4682]

I have also been interested in converting my 2f to FI using the fi kit. Does anyone have some real numbers as far as hp and torque gains. I have already replaced my worn out 2f with a low milage 2f and have no intentions of pulling the motor again, so an fi kit seems like a great option. I do love the simplicty of the 2f.

 

[elripster]

Keep in mind, carbed engines can make loads of power. FI engines can as well but usually because they flow air in and out of the engine much better and can better atomize the fuel over a wide range of flow rates. Soooooo I would strongly suggest finding some performance numbers before TBI'ing a 2F. The 2F has terrible intake and exhaust flow characteristics so it is unlikely you will see a power increase with the FI kit on par with what a 3FE head swap would get you.

In short, if the engine flows less air, the EFI will simply squirt less fuel to maintain stoich air/fuel ratio.

Frank

 

[pappy]

Revisited the Fourwheeler magazine article that converts an FJ60 to a 3FE.

This thought came up when reading the specs for each engine:

The 2F makes 135hp@3600rpm, 210 fp@1800rpm.
The 3FE makes 155hp@4000rpm, 220 fp@3000rpm.
My 2FE makes 151hp@3250rpm, 284lb-ft@1950rpm
The 2F compression ratio is 7.8-1
The 3FE compression ratio is 8.1-1
The 2FE compression ratio is 9:1

I finished the table for you. The best of both worlds. Multi-port EFI and long stroke.

I believe it was Mark W. who said the 2FE was the engine Toyota should have built.

 

[elripster]

And that is why I wish I could stroke the 3FE and keep all the 3FE accessories. Oh well.

Frank

 

[GLTHFJ60]

I finished the table for you. The best of both worlds. Multi-port EFI and long stroke.

I believe it was Mark W. who said the 2FE was the engine Toyota should have built.

Hold the phone, your 2FE makes 284 lb/ft? Do you have a RV cam in it?

I did not realize that the 2FE made so much more power.

 

[elripster]

The 2FE actually makes less power than the 3FE but it really comes down to the are under the torque curve and with 284 ft-lb you have more of it. I bet it's a very drivable engine.

Frank

 

[pappy]

My engine was "hot rodded" during the rebuild doing all the usual stuff. Balanced, head work, camshaft. I didn't just take the 3FE bits and bolt it onto a high mileage 2F. If you look at the numbers both the hp and torque are in very usable ranges. And the torque is substantially more than both engines. I make 200lbft at the rear wheels between 1150rpm and 3250rpm. The torque curve is damn near flat. Very friendly driving around town, on the freeway, and on the rocks. This just shows the potential for this combination.

I love this engine.

 

[freepowder]

As said above - tbi is easiest and not a bad option.

I ditched my 3F carbed engine for a 2F . What Mark said is true. The 2F is more drivable offroad .
Now in the process of getting all the parts for efi conversion. It is costing me a lot as shipping to Africa is not cheap. If I lived in the US , building a 2F-e would be a nobrainer. The parts are easy to find and relatively cheap.

Here's all the parts in one place, computer flashed AND a GM dizzy:
Toyota: Affordable Fuel Injection
Before everyone freaks, it's sourced by AFI from Howell.