3F-E or 2F advice (1 Viewer)

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Are you running a CAT, assume desmogged not? Where is the exhaust run, inside or outside the frame? Have you been running with bellhousing motor mounts with an H55F for ten years?

Questions about 2FE verses 3FE. Gain in torque and HP with 2F block over the 3F block? What accessories (A/C compressor, PS pump and alternators) do you run with each? Is it easier running the 3FE accessories with a FJ62 wiring harness? 3F block uses the same front motor mounts as the 2F?

Alex if you want will gladly delete my post. Just think these are good questions related to the conversion.

Mine is a 3FE. No cat, de-smogged, exhaust inside the frame (I made the down pipes), I have a trans cross member, no bellhousing mounts. I am running the stock 3fe alternator, PS pump and AC compressor. I also have the york on board air. The 2f mounts fit the 3f block but the frame side mounts need to be slotted. I used the 3fe passenger side mount for the AC compressor. I also added some shims to the front mounts to get the fan in the correct place for the fan shroud. The alternator wiring is part of the fj62 cowl harness which I did not use. I just wired it into the 40 harness. The AC clutch power also feeds into the ECU to up the idle. I use this feature with my "idle up" switch so I can increase idle for winching and airing up.

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The reason I asked about the rear motor mounts is the picture you posted shows the driver side motor mount bolted to the bellhousing. Exhaust routing was because I will run a PTO which outside the frame is a big advantage. With a carbuarated 2F and single pipe would route over the frame on my 79 because Toyota routed under the frame 79/80 only in markets with a CAT. All other markets went over the frame. With a steering box on left side curious how the two piece would route outside the frame. Where did you two pipes join? Only running a single muffler? Wonder if a 2FE with a stock manifold might be a better option. 3F would lower the exhaust which would make it harder to route outside the frame without going under it. It appears yours is a 9/72-9/75 build date. With the H55F and split case how did you deal with the hand brake?
 
The 3F-E actually had higher HP and only slightly less torque between 2800 RPM to 3600 RPM.
But I was scaling graphs so it could have been within my margin of error.

This makes perfect sense, as hp = torque x rpm, and as the 3F is a de-stroked 2f, it can rev higher, which yields the higher hp despite losing a bit of low-end torque. This is exactly why Toyota de-stroked the 2F to make the 3F; more hp on the top end for the heavier FJ62 and FJ80.

The beauty of the 2F as a wheeling motor is that it makes 80% of its peak torque just above idle rpm, the great advantage of a stroker motor.
 
This makes perfect sense, as hp = torque x rpm, and as the 3F is a de-stroked 2f, it can rev higher, which yields the higher hp despite losing a bit of low-end torque. This is exactly why Toyota de-stroked the 2F to make the 3F; more hp on the top end for the heavier FJ62 and FJ80.

The beauty of the 2F as a wheeling motor is that it makes 80% of its peak torque just above idle rpm, the great advantage of a stroker motor.
Good point! However you can get both if you do it with a wide set of gear ratios instead of a high torqued motor. Too bad that Marlin crawler gears are not available for my 40.
 
Having driven two 3FE 40’s (one of which we owned) I can tell you that you cannot tell that a 3FE is lower torque than it’s father, even in difficult low RPM situations. You can darn sure feel the difference in horsepower. The motor pulls strong through its power band which is wider than the 2F. Bottom line it’s a great motor in a 40, more usable HP and fuel economy that’s about 25-30% better than the carbureted 2F.

If I lost the motor in my 40, I’d be on the hunt for a 3FE. No experience with a 2FE but it’s hard for me to imagine the gain is worth the effort over a 3FE for use in a 40.
 
Having driven two 3FE 40’s (one of which we owned) I can tell you that you cannot tell that a 3FE is lower torque than it’s father, even in difficult low RPM situations. You can darn sure feel the difference in horsepower. The motor pulls strong through its power band which is wider than the 2F. Bottom line it’s a great motor in a 40, more usable HP and fuel economy that’s about 25-30% better than the carbureted 2F.

If I lost the motor in my 40, I’d be on the hunt for a 3FE. No experience with a 2FE but it’s hard for me to imagine the gain is worth the effort over a 3FE for use in a 40.
That's great to hear and your words are putting wind in my sails. Hopefully the added complexity will be worth the trouble.
 
The reason I asked about the rear motor mounts is the picture you posted shows the driver side motor mount bolted to the bellhousing. Exhaust routing was because I will run a PTO which outside the frame is a big advantage. With a carbuarated 2F and single pipe would route over the frame on my 79 because Toyota routed under the frame 79/80 only in markets with a CAT. All other markets went over the frame. With a steering box on left side curious how the two piece would route outside the frame. Where did you two pipes join? Only running a single muffler? Wonder if a 2FE with a stock manifold might be a better option. 3F would lower the exhaust which would make it harder to route outside the frame without going under it. It appears yours is a 9/72-9/75 build date. With the H55F and split case how did you deal with the hand brake?

I think it would be nearly impossible to go over the frame. My down pipes merge in the horizontal section near the crossmember then into a single muffler. I found a later rear axle with handbrakes and modified the hump to get real estate to mount the handle.


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I think it would be nearly impossible to go over the frame. My down pipes merge in the horizontal section near the crossmember then into a single muffler. I found a later rear axle with handbrakes and modified the hump to get real estate to mount the handle.


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Here is how exhaust was run 1/79+ in markets no CAT. Same part number LHD and RHD.
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Will graft this into my 3/79.
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Also using the 40 series top cover which keep the transmission cane in the same location as the four speed.
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