3FE vs 2F

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Thanks , but I have already imported a 3F-e head at a cost of $1500. Most of the other part has reached me as well at additional cost . As you can see I want a 2F-E and willing to pay for it.
The easier solution would have been TBi .

Who wants easy ? Furthermore I prefer Toyota parts. Biggest reason for conversion is economy and not power . Other reason is that I am considering Turbo and that needs efi. ( I doubt that will happen even though I already have the turbo sourced )
 
As far as i can tell, the 3F engine came about for two reasons... It brought the displacement down to 4.0 liters to avoid tax penalties on larger engines and it lowered the height of the motor to fit under the hood with the efi on top.

To do this, they had to shorten the block a lot and also shorten the rods. The stroke is not all that much shorter really...

This results in a lot of side loading on the pistons... and very short piston skirts... and a piston that drops WAY lot out of the bore in the block...

At first thought it might seem that the 3f with the lighter rotating assembly and shorter stroke will rev higher than the 2F before things go boom. Nope... the side loading on the pistons is severe and the skirts will crack at high rpm. Lower than the rpm where 2F rod bolts stretch usually. And 2f rod bolts can be replaced with stronger ones.... can't do anything about the situation in the 3F however.


The longer rod in the 2F means more torque for the same amount of power applied at the top of the piston. Longer stroke helps bring the beginning of the powerband lower in the RPM range too.

There is really nothing that the 3f has that is a gain over the 2F... it is the "E"... the EFI that produces any and all benefits that you might encounter when you compare the 2F and the 3FE. (

Things like more powerful alternators and the like really are not relevant when comapring the differences /advantages/disadvantages.

If you that the same ignition, induction fuel delivery and exhaust system as the 3FE has and hang it on a 2F... you get a better, stronger, more powerful motor. go ahead and put the cam in there that Toyota should have done as well, and raise the compression levels to suit the fuel we have available (instead of expecting it to run on Mexican ditch water the way the factory designed it to do)... And you will have a motor that will amaze those who have never seen a warmed over F series engine.

And yes it was me that said that this is the engine that Toyota SHOULD have built. ;)

As to the TBI conversions... GM TBI on top of an OEM 2F intake will never stand up to the multiport system on the 3FE

Mark...
 
Thanks Mark for the explanation. The side load issue is one had had not thought of.

3FEs seem to go to extremely high mileage without too much effort.

I have the ingredients for a 2FE and will eventually make that happen.
 
The 3f is a great motor. I have one in an FJ80 that still had 165psi cranking pressure at 250k miles before I drowned the whole rig in a river and turned it into a parts car. ;( I used that rig hard, towing a car trailer with Cruisers and even a suburban all over the place with it. The 3F is a GREAT motor. The side loading on the pistons is not a concern for 99.9995 of the people who will never try to push the engine anywhere near it's limits But the 2FE is even better... with more generous limits as well as more power potential. ;)


Mark...
 
I can't find the pic, but I've seen a boneyard 3FE with a hole in the side of the block.
 
Sometime I need to try pushing my 2FE to high rpms. So far with the extra umph it has in the normal driving range, I haven't needed to push it beyond 3500 rpm very much. I don't think it's ever seen north of 4000.
 
pappy said:
I can't find the pic, but I've seen a boneyard 3FE with a hole in the side of the block.
Click to expand...


At one time I had 10 2Fs with destroyed bottom ends... holes in blocks, oil pans that looked like a shotgun went off inside them, crank journals torn loose... all sorts of fun stuff. I have three or four broken 3F pistons around here somewhere too. ;)


Mark...
 
RockDoc said:
Sometime I need to try pushing my 2FE to high rpms. So far with the extra umph it has in the normal driving range, I haven't needed to push it beyond 3500 rpm very much. I don't think it's ever seen north of 4000.
Click to expand...

4000 is a nice safe redline to work with. And will serve all your needs 90% of the time. I turn pretty much any 2F/3F I drive that high routinely myself. 5000 should be no problem on a carefully built motor. I would not take it over 5000 with OEM rod bolts.


Mark...
 
Mine pulls to 4000 easy, but I've not had the guts to go past. It sure seems to want to.
 
I've taken my 2F past 4000. Not on the road though. Thats spinning tires in mud. Did I mention IH8MUD?
 
I will say that I like not having a smog pump under the PS pump. It should last a lot longer. I also think the better accessories help. My PS wasn't all that before my 80 series 3FE swap, now it's solid. Extra amps may or may not matter but if you want to add lights and stuff it does help.

That said doing a water pump on a 3FE is quite painful compared to a 2F.

Frank
 
elripster said:
I will say that I like not having a smog pump under the PS pump. It should last a lot longer. I also think the better accessories help. My PS wasn't all that before my 80 series 3FE swap, now it's solid. Extra amps may or may not matter but if you want to add lights and stuff it does help.

That said doing a water pump on a 3FE is quite painful compared to a 2F.

Frank
Click to expand...


some of the things you mention are improvements. I just meant that these type of things don't really factor into which is the better motor or better design.


Besides, motors can be desmogged, alternators can be upgraded (the 80 series is not exactly a monster either... I run a pair of them in my '62)... PS systems can be tweaked (any gain that you found when you swapped was almost certainly just because you had a tired pump to begin with BTW)

All that stuff is in the venue of owner improvements in my opinion. ;)



Mark...
 
I haven't had issues or heard of anyone else having issues with the 3FE ECU handling the extra displacement of the 2F bottom end.
 
My experience is that the ECM has more than enough adjustment/compensation range so that you do not need to worry about this . In 2FEs with stock cams and in 3FEs and 2FEs with longer duration/higher lift cams the ECM has handled the changes without any apparent hiccups. Altering the compression ratios has not seemed to trip it up either. this is after all a pretty simple EFI system.

I would venture that if you wanted to get still more power, you could do a megasquirt conversion, install different injectors (for more fuel flow capability), bore out the throttle body a bit, and play with a few more variables too I bet. But these are mods I do not have any experience with yet.


Mark...
 
My problems which led me to the 3FE were largely related to Cali smog. I might have gotten a 2FE through assuming the BAR tech didn't know what he/she was looking at but if they did I'd have had some expensive problems on my hands.

Frank
 
I am not at all unhappy with the cammed and desmogged 3FE with boosted compression that I have in my '62. Just because I think a 2FE is better does not mean that the 3FE is bad. ;) And the stocker I had in my '80 was a hell of a motor. Running on 285s it pulled trailers as well as my 1FZ powered rig did on 315s
 
That's good to hear. I am happy with the 3FE and have no regrets at all swapping it in my 60. If it ever needs a rebuild I will likely be researching your threads on what you did to yours.

Frank
 
pappy said:
Mine pulls to 4000 easy, but I've not had the guts to go past. It sure seems to want to.
Click to expand...

I just returned from a desert trip in the Namib desert ( last week ) and regularly went to where the rev counter stops at 5000 rpm in my rebuilt 2F. ( the rev counter max'ed and it could have been above 5000 rpm)
The fan makes a lot of noise making it sound worse than it actually is but the engine can handle it . ( the fact that I have ARP conrod bolts in there and the whole engine is balanced gives me a bit of peace of mind )

yspen-albums-bensa-picture21951-namib-123.jpg



This thread has re-motivated me to get going with the MPFI
 
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pappy said:
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.
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Ah. Well met, Pappy. It does change things significantly when you see WHERE everything happens.

Likin' my 2F. Still thinkin' 2f/TBI is the hot ticket for ease of conversion, cost effectiveness and off road wonderfulness.
 
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