V8 Swap: What am I up against ? (1 Viewer)

[Broc2C]

I purchased a '72 fj40 a few weeks ago and was in the process of putting life back into it (a classic barn find, if you will) when a serious knock developed: spun bearings for sure. The current engine is an early F (not original) and had been "re-manufactured" as evident from a tag on the block.

I am entertaining the idea of putting in a Chevrolet V8, keeping it really simple (no computers, OBD etc,): carbureted and retaining the factory drive train (3 spd trans & transfer case) I don't have the funds or desire for anything more.

As I understand, I can use a kit provided from Advanced Adapters to facilitate this. Aside from altering the drive-line what else needs to happen? Will the engine mounts provided in the kit bolt to the existing, or is welding necessary? What type of exhaust manifolds are recommended....etc...?

Any advice would be appreciated. If this has been answered in the past, please direct me to the thread(s).

-Thanks!

 

[shawnfj40]

I am pretty sure AA kits have all of your answers for you. They have all of their installation instructions online I am pretty sure. Downey has just about every swap answer you will ever need as well.

 

[UltraFJ40]

I am pretty sure AA kits have all of your answers for you. They have all of their installation instructions online I am pretty sure. Downey has just about every swap answer you will ever need as well.

Get the F out, I'm in East Naples. I didn't know that there were any other Mudders from here except Jason. Nice to see another here and good advice by the way. Yes, I've probably said that to you before but I can't remember sh*t.

 

[cult45]

Purists.

 

[shawnfj40]

Or if you just want to replace the F motor with another f motor, I have one.

 

[3_puppies]

you don't have the funds or desire for anything more?
cost wise it will be more money to install a V8. lots of small thins adding up on the install, driveshafts, throttle linkage, radiator/cooling,
keeping the 3 speed is doable but it is much nicer with a 4 speed.
I think the motor mounts will need to be welded in place, positioning the engine is fairly important.
fins another F or 2F and install in a weekend and drive and see how you like the rig.
it has happened many times before, someone starts a project like this, gets most of the pieces, owner either loses interest or realizes they are in over there head and the project sits and finally gets sold unfinished.

 

[69LC]

I have a couple of GM belhousings, the plate adapter for the 3-spd, turned down throwout bearing snout and rear crossmember if you’re interested. I’d have to pull them, but they will need a new home...

I don’t have the corvette style from SBC engine mounts. Had to fab my own.

 

[RWBeringer4x4]

I recently went through this. My truck came with a very poorly installed 283. When it died, I swapped to it a bare-bones crate 350 (carbureted, Rochester Quadrajet).

I used a Downey conversion bellhousing and have been happy with it (not sure if @Downey has more of these still kicking around, but it’s another option).

DEFINITELY go with a conversion bellhousing. A lot of older mods required customizing the transmission snout or throw out bearing, adding plates around a GM bellhousing, or drilling your own holes to mate the two via a lakewood scattershield bellhousing (this is what mine came with). It is very difficult to get the engine and transmission aligned properly. The aftermarket conversion bellhousings, while pricey, are dowel-aligned and make installation a piece of cake.

From a fab perspective, to do it right, you will need to cut off the F motor mounts, and weld in the Adapter mounts in the appropriate location for the V8. You will also probably need to knock out or cut off the stock rivetted radiator mounts to lower the radiator which will better line it up with the V8. The easy way to do this is to weld or bolt a piece of bar stock across the bottom of the frame and mount the radiator to it. I got a little fancier and fabbed some brackets that mount through the original rivet holes. You will also probably want to build or buy a fan shroud and a 4-core OEM, or a bigger aftermarket aluminum radiator as the V8 will make the engine bay a lot hotter than the F motor did.

Another GREAT idea is to go find the transmission top plate from an early M/T FJ60. This bolts right to a stock FJ40 4-speed, and moves the shift tower back about 3 inches. This will allow the transmission shifter to mount basically in the stock location, and avoids needing to cut the transmission tunnel or dog leg the shifter out from under the heater. Of course, this won’t work with your 3-speed.

As for exhaust manifolds - just use stock GM Ram’s horns. You will be very tight to the steering column in the driver’s side. Ram’s horn manifolds flow plenty well and offer about the best clearance you can get.

From there you’ll need to modify your driveshafts to match the new location of the transfercase.

It’s a lot of work, and expensive no matter how you slice it. Rebuilding the F motor is pricey, but the engine conversion and all the additional modifications was probably $5k when all was said and done. Keep in mind, this included virtually all new components and accessories, radiator, clutch, pulleys, etc. and a brand new engine which was a big chunk of it ($1700).

I re-used my intake manifold and the rear AA-style “propeller shaft” adapter that mounts to the rear of the transfer case. Otherwise I pretty much had to buy everything.

If you feel like slogging through my build thread I took a LOT of pictures. Page 54-57 has a lot of the measurements for the engine mounts.

The new engine went in around page 65.

Keep in mind I had NEVER welded or done anything of the magnitude before and it came out fine.

@Broc2C - By the way, I have a spreadsheet with part numbers, etc. for most of the stuff I bought to do this conversion. If you want it, PM me your e-mail address and I'll send it over.

 

[dmaddox]

Purists.

This. Also, there's a ton of info in the Tech section as well as several builds. Being a purist myself, I'd find a good F, rebuild it and retain the sound/smell/originality of the cruiser. You'll also retain value and with any modification - it is nice to crack open a FSM and know that you can follow along - or go to the parts store and order parts for your FJ40....not a 1981 el camino.

 

[troy scott]

you don't have the funds or desire for anything more?
cost wise it will be more money to install a V8. lots of small thins adding up on the install, driveshafts, throttle linkage, radiator/cooling,
keeping the 3 speed is doable but it is much nicer with a 4 speed.
I think the motor mounts will need to be welded in place, positioning the engine is fairly important.
fins another F or 2F and install in a weekend and drive and see how you like the rig.
it has happened many times before, someone starts a project like this, gets most of the pieces, owner either loses interest or realizes they are in over there head and the project sits and finally gets sold unfinished.

Absolutely right I am on the downhill slope of this project right now. I started in 2008. l went with the marks adapter to save many issues and it did. But created many more. I wouldn't do it again. I thought it would be easier but just yesterday i had to raise my motor cause because of something I didn't think about. Several years later I wish I had found a 2f and been done. Ive also figured out as I've gotten older that the original is also the coolest. Nothing looks better in a fj40 than a clean full dress 2f

 

[RWBeringer4x4]

My truck was already hacked up for a V8 so going to a different V8 was still the low hanging fruit. I agree that original/all toyota is cooler, but aside from the purists argument, I do find the V8 to be a much more street-able, traffic-friendly engine. The extra power makes it much more driveable on a regular basis. Plus, around here, parts stores don't carry anything for an FJ40 - but they sure do carry just about everything I'll ever need for a 350 small block.

That being said, if I was going to do it again, I probably would have opted for a roller-block TBI motor. I didn't feel like messing with computers and electric fuel pumps either, but I sure get sick of messing with quadrajets. The difference in cost, when I priced it out, was about $800. So...maybe 5k instead of 4k, and a bit more wiring/fuel system work. I couldn't see my way out of a modern LS swap for less than $7k which was money I wasn't willing to spend.

 

[4x4veteran]

I purchased a '72 fj40 a few weeks ago and was in the process of putting life back into it (a classic barn find, if you will) when a serious knock developed: spun bearings for sure. The current engine is an early F (not original) and had been "re-manufactured" as evident from a tag on the block.

I am entertaining the idea of putting in a Chevrolet V8, keeping it really simple (no computers, OBD etc,): carbureted and retaining the factory drive train (3 spd trans & transfer case) I don't have the funds or desire for anything more.

As I understand, I can use a kit provided from Advanced Adapters to facilitate this. Aside from altering the drive-line what else needs to happen? Will the engine mounts provided in the kit bolt to the existing, or is welding necessary? What type of exhaust manifolds are recommended....etc...?

Any advice would be appreciated. If this has been answered in the past, please direct me to the thread(s).

-Thanks!

Lack of funds is not as much a problem as lack of desire.
Pulling the six and rebuilding or replacing with another on would probably be the simplest way.
Loved the old six and hated to get rid of it years ago but in my case the V8 was the fastest, despite the extra work, and cheapest way to go at the time.
If you have never crawled around in a FJ40 with the stove-bolt six then you will like the V8 right off and not know what you are missing.
I used the AA kit in the 80's and had my cruiser back on the road with in a week of receiving the kit.
Didn't have a lot of money or really know what I was doing but had the desire plus the need to get back on the road asap.
Didn't have the internet forums to ask questions like you do but managed to get it done.
My Toy is a 70 and I used the stock 3 speed and transfer with no problems for the past 30 years.
I had no idea on placement of engine so hung it in the engine bay where it looked right, bailing wired it in place and started measuring.
One of the first things I found was the driveshaft length was a problem and it would cost money to have new ones made up so after some more measuring I found that swapping front an back driveshafts would fit almost exactly with my engine placement.
Chevota conversions are common so getting advice will be no problem whether you go 8 or 6 cylinders which brings us back to the question of can you do it.
Ambition and desire comes first. With out those, quit now.
Skill; There are some on this forum that had no experience starting into their project but have built some really nice rigs.
Funds; I never qualified for any kind of assistance but never had a lot of money in my younger years but did have desire and ambition so in spite of lack low cash flow managed to build some fairly nice motorcycles and cars.
As always we need pictures of your rig, wife and or girlfriend if applicable.

 

[troy scott]

My truck was already hacked up for a V8 so going to a different V8 was still the low hanging fruit. I agree that original/all toyota is cooler, but aside from the purists argument, I do find the V8 to be a much more street-able, traffic-friendly engine. The extra power makes it much more driveable on a regular basis. Plus, around here, parts stores don't carry anything for an FJ40 - but they sure do carry just about everything I'll ever need for a 350 small block.

That being said, if I was going to do it again, I probably would have opted for a roller-block TBI motor. I didn't feel like messing with computers and electric fuel pumps either, but I sure get sick of messing with quadrajets. The difference in cost, when I priced it out, was about $800. So...maybe 5k instead of 4k, and a bit more wiring/fuel system work. I couldn't see my way out of a modern LS swap for less than $7k which was money I wasn't willing to spend.

Alot of what you said is what also pushed me to a v8 went with a 5.3. I haven't got to drive yet that may also change my mind LOL

 

[troy scott]

Lack of funds is not as much a problem as lack of desire.
Pulling the six and rebuilding or replacing with another on would probably be the simplest way.
Loved the old six and hated to get rid of it years ago but in my case the V8 was the fastest, despite the extra work, and cheapest way to go at the time.
If you have never crawled around in a FJ40 with the stove-bolt six then you will like the V8 right off and not know what you are missing.
I used the AA kit in the 80's and had my cruiser back on the road with in a week of receiving the kit.
Didn't have a lot of money or really know what I was doing but had the desire plus the need to get back on the road asap.
Didn't have the internet forums to ask questions like you do but managed to get it done.
My Toy is a 70 and I used the stock 3 speed and transfer with no problems for the past 30 years.
I had no idea on placement of engine so hung it in the engine bay where it looked right, bailing wired it in place and started measuring.
One of the first things I found was the driveshaft length was a problem and it would cost money to have new ones made up so after some more measuring I found that swapping front an back driveshafts would fit almost exactly with my engine placement.
Chevota conversions are common so getting advice will be no problem whether you go 8 or 6 cylinders which brings us back to the question of can you do it.
Ambition and desire comes first. With out those, quit now.
Skill; There are some on this forum that had no experience starting into their project but have built some really nice rigs.
Funds; I never qualified for any kind of assistance but never had a lot of money in my younger years but did have desire and ambition so in spite of lack low cash flow managed to build some fairly nice motorcycles and cars.
As always we need pictures of your rig, wife and or girlfriend if applicable.

Yes what he said

 

[shelfboy1]

if you can find a good 2f block all the 72 goodies will bolt right on .i have installed many v8s in 40s never thought it was that hard i geuss its up to the person doing it .good luck

 

[Broc2C]

Thanks everyone, for the input. Definitely fear that this could be an extended project going the way of a V8. Not a huge fan of the F engine, but like the 2F very much. This begs the question....What will it take to install a 2F? Are rebuild kits still available for the F and or 2F? What would it take for the 2F or f.5 install? I can imagine mating to the three spd. would require some work. It may be that I keep it simple/original and rebuild another f. I've posted some pics. Check out the serial number on the block...I'm guessing pre 1968. Can anybody provide an actual year of manufacture? ( 259802 )
Thanks-

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[Fj moneypit]

Thanks everyone, for the input. Definitely fear that this could be an extended project going the way of a V8. Not a huge fan of the F engine, but like the 2F very much. This begs the question....What will it take to install a 2F? Are rebuild kits still available for the F and or 2F? What would it take for the 2F or f.5 install? I can imagine mating to the three spd. would require some work. It may be that I keep it simple/original and rebuild another f. I've posted some pics. Check out the serial number on the block...I'm guessing pre 1968. Can anybody provide an actual year of manufacture? ( 259802 )
Thanks-

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If that’s the cruiser you’re going to put a v8 in, I’d put a modern v8 or go back to stock. It’s looks to nice for an old school chevota. Looks like my fj40. It’s got a 2F in it. I’m sure it was an easy swap. Good luck with whatever direction you choose.

 

[Downey]

Broc2C, if you opt for V8, (a) the installation instruction manual is printed here on Mud on the Downey Off Road link, perhaps you could read it to see what's involved before you spend a dime, and (b) I do have the 4 speed adapter and front and rear mounts you would need in stock at this moment- - -not always in stock every since I closed Downey in 2009, and now merely restore old Downey parts as I get them.

 

[RWBeringer4x4]

I'm not an F motor expert as I've never had one, but I know this has been done countless times, and from my understanding, it's fairly straightforward. I believe mounting a 2F in front of a 3 speed is almost a direct swap. I think the bellhousing bolt patern is the same. I'm not sure about clutch components, but I imagine you could stick with the 3-speed clutch, pressure plate, and throw-out bearing fork (but again, don't quote me on this). I'd check to see if there was a change in the pilot bushing between the two engines. The wiring and exhaust manifolds are different so you might run into some clearance issues around the carb/air cleaner. I think the mount bolts on a 2F are also bigger, so you'd just need to bore out the F mounts slightly a bit to accept the bigger bolts (or perhaps just use F motor mounts??). That said, if you can find a good 2F I imagine it would be a more drop-in swap than a V8.

 

[Downey]

How times have changed, back in the day guys couldn't wait for the 6 cylinder to blow up so they could rationalize going V8. If you are not a purist, go for the V8 for better H.P., better M.P.G., radically better in off road terrain, radically better (and cheaper) parts availability, and an engine that does not sound like it's flying apart at 3,000 rpm.