FJ40 Engine and transmissions (1 Viewer)

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Just curious on what everyone is throwing into their fj40's as far as pairing an engine and transmission and how much they have spent on it. I am looking for the oem straight 6 or a small block 350. I am looking to convert into automatic and I am unsure which transmission to pair up to that as well. Any help would be greatly appreciated. Thanks for everyone's time.
 
SBC and a slush box has been done plenty of times; the biggest problem (IMO) is the short-wheel-base 40 doesn't leave you much room for a drive shaft with that set-up. Someone else who's done it will have to chime in.

My drive line choice is: 2F, H41, Orion 4:1 transfer case, 3.70 diffs.
 
You won’t have a problem with a sbc engine with th350 auto tranny, even with the longer AA adapter. These conversions were even better when Downey made the 1 inch thick adapter plate, guys could then have a longer rear drive shaft. Also, you could always cheat the sbc forward a smidge???
 
What do you guys think of a sbc 350 and a turbo 350
I wouldnt spend a dollar on a SBC if it wasnt already running and in my rig. A 4.8, 5.3, or 6.0 V8 is the only way to go. I have a SBC 350 and TH350 in one of my 40’s. If i drove it on the road much, i would want an OD transmission. RPMs are pretty high for highway cruising. The cost increase to go to a fuel injected newer V8 over and older SBC is not that much and they are better in so many ways.
 
What is your intended use? An around town driver vs hard core wheeler vs long(er) range overlander, all may be different drivetrain choices.

Btw - Welcome to mud!
 
I wouldnt spend a dollar on a SBC if it wasnt already running and in my rig. A 4.8, 5.3, or 6.0 V8 is the only way to go. I have a SBC 350 and TH350 in one of my 40’s. If i drove it on the road much, i would want an OD transmission. RPMs are pretty high for highway cruising. The cost increase to go to a fuel injected newer V8 over and older SBC is not that much and they are better in so many ways.
So you believe going older is better? It's a 4500 dollar and it seems pretty high end
 
What do you guys think of a sbc 350 and a turbo 350
Not Much..
The SBC is an "RPM" Engine.. meaning it produces it's max torque/horsepower in the higher RPM range.. Not very helpful when idling up some steep incline..
The TH350 is fine in a street Chevy.. not worth a damn under a load.. like pulling a long incline at a slow speed.. in fact, my Mom had a stock TH350 (fitted behind a 390cid 1962 Caddy V-8) literally, "drop dead" in downtown Ft. Worth traffic! (Cadillac was having a LOT of issues with the TH350's in their early '60's cars)
I installed a 1967 429cid Cadillac V-8 AND a TH400 into my '74 FJ40 back in 1978.. I spent a LOT of miles pulling a 6000lb, 23' travel trailer, cattle and hay trailers AND even pulled two 18 wheeliers up ice slick hills one winter. The 429 Caddy produces a LOT of low-end torque.. I feel THIS is what a 4wd NEEDS.. NOT horsepower at 5000rpm!
I will add that I had my TH400 "built".. that is extra heavy-duty "stuff" (plates, clutches, etc.) put into the Turbo Hydramatic to make sure it stayed together during a LOT of low speed "abuse" (it also runs very well at 70mph!).. Twenty years and 300K miles later, the engine finally wore out... but the TH400 was still working like a champ!!
In short, go with the TH400 AND an engine with more low-end torque!! Unless you are building a "strictly street 4wd"!
Charles 1974 FJ40.
 
So you believe going older is better? It's a 4500 dollar and it seems pretty high end
No, the SBC you are asking about is old design/tech. A newer LS series engine is the way to go and there are tons of options to chose from. From a cast iron block 4.8L to an aluminum block 6.2L LS3 and beyond, the LS platform offers tons of options and they are all superior to a SBC. Cost is dependent on your ability to perform the work yourself, source parts, and be resourceful. You could spend $3-4k being thrifty and doing it all yourself, or you could spend $15-20k buying all new parts and paying someone to complete the work.

What is in your FJ40 now for power and drivetrain and does it run? Personally, for a driver/cruiser, I would want the Toyota H42 4 speed and stock inline 6. If it was a commuter and your only vehicle, I would agree that an LS V8 with automatic would be preferred, but I think there are thousands of better options for an only vehicle than a V8 swapped FJ40.
 
No, the SBC you are asking about is old design/tech. A newer LS series engine is the way to go and there are tons of options to chose from. From a cast iron block 4.8L to an aluminum block 6.2L LS3 and beyond, the LS platform offers tons of options and they are all superior to a SBC. Cost is dependent on your ability to perform the work yourself, source parts, and be resourceful. You could spend $3-4k being thrifty and doing it all yourself, or you could spend $15-20k buying all new parts and paying someone to complete the work.

What is in your FJ40 now for power and drivetrain and does it run? Personally, for a driver/cruiser, I would want the Toyota H42 4 speed and stock inline 6. If it was a commuter and your only vehicle, I would agree that an LS V8 with automatic would be preferred, but I think there are thousands of better options for an only vehicle than a V8 swapped FJ40.
Right now it has the original inline 6 and stock transmission
 
Right now it has the original inline 6 and stock transmission
Does it run and drive? Does the truck stop? Completely road worthy?
 
Not sure I agree with jag666’s math, last time I checked the sbc 350 put out more torque at an even lower rpm than the stock 6 cylinder???
 
Not sure I agree with jag666’s math, last time I checked the sbc 350 put out more torque at an even lower rpm than the stock 6 cylinder???
Jim;
I picked-up your gauntlet and dug into the various specs of the three engines in question.. A Toyota FJ40, A Chevy "Small Block" and, of course, the Cadillac 429cid V-8.
As I have a 1973 Toyota "F Engine" service manual, I used the specs from that book, to wit:

Toyota FJ40. Circa up to 1973.
Max HP: (SAE Gross): 155HP at 4000rpm
Max Torque: (SAE Gross): 230 Ft Lbs at 2200rpm
Comp Ratio: 7.8:1
CID: 236.7 Cu In.

From "a' Toyota on-line site:
FJ40, 3.9L Inline Six (F and F2 spec)
1960-1974 HP: 125hp @3600RPM.
1975-1983 HP: 135hp @3600RPM.
1960-1974 Torque: 209 Ft Lbs @2000RPM.
1975-1983 Torque: 210 Ft Lbs @1800RPM.

Chevy V-8: (limited to the 327cid and 350cid "street car" engine as likely to be most easily obtained from salvage yards) circa 1962-2003
Power Output: 110-475hp.
Torque Output: 215-400Lb Ft. (Note: Includes the 400cid V-8 and DOHC 4 Valve V-8's).
NO RPM Rating Listed for ANY SBC, BUT specs DID note: "Redline: 6500rpm"!!
Also, Street Car Engines ran at lower HP/RPM and CR Levels. I say this as most Chevy V-8's used in "engine swaps" have a high probability of being "wrecking yard picks", thus: worn-out street cars! (albeit rebuilt!)

Cadillac 429cid V-8:
Stock Power Output: 340HP @480 Ft Lbs Torque at 4400RPM with 11.5:1 CR.

So, in part you are correct.. Chevy DOES put-out more torque at "up to" 400FT Lbs. BUT, the ONLY RPM Level
I could find was listed as: "A 6500RPM RedLine".. Don't know what you think, but, to me, that's twisting the hell out of an engine. (tho I built and campaigned an AMA Pro GP RoadRacer with a powerband of 3000 to 9000rpm and ran against Yamaha's with a powerband of 12000 to 12500rpm.. They could NOT keep-up with me!)

As to your comment of: "...the sbc 350 put out more torque at an even lower rpm than the stock 6 cylinder", the (above) fact shows the Toyota Six Cylinder puts out 230lbs of max torque at a rather low 2200RPM while the "SBC" puts out it's MAX Torque of 400Ft Lbs (twice as much), but HAS to spin at 6500 RPM (THREE TIMES higher than the stock FJ-40!! AND nearly twice that of the Caddy V-8) to do this.. The Facts do NOT jive with your statement!!

Which goes back to my original comment that the SBC Engine IS "an RPM Engine".. and, in my opinion, not really suited to be fitted into a ground-grabbing, rock-crawlin', hill climbing, "Get-Down Grunt" Four Wheel Drive Vehicle!
Charles 1974 FJ40.
 
Right now it has the original inline 6 and stock transmission
Leave it alone. Around town and for most light wheeling you'll be fine.

While there's no substitute for cubic inches, if you're seriosly looking at a gas V8/auto I'd opt for a SBC stroked to 383. Use a with low rpm cam and a ultra low stall converter in a T350 and you'll have plenty of grunt. 700R and T400 trannies are a bit longer but can work. 700s can be built almost as strong as a T350 these days but you can just throw some bigger diameter tires on for your overdrive.
 
Around tow

Around town mostly
Put a 4sp trans in it for a little better drivability. Get it running good. Yes, it can be done.
You'll learn a lot and it will be fun for around town.
 
Jag666, last math I remember reading was that the 6 cylinder put out about 220 ft. lbs @ 2200 rpm, and a sbc 350 put out about 240 ft. lbs. @2000 rpm, but I'm too old/retired to do the research again.
 

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