Pontiac V8 engine swap?

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Hi Everyone!
I've just purchased a 1969 FJ40 from a good friend who also referred me to this site. The truck is not running/has a bad engine and has been sitting for 10 years. So...I have a 1970 Pontiac 455 V8 sitting around that I'd like to put into this rig. Can this be done? Thanks for any help! -Tom
 
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Yes:cool:, anything can be done, as long as you have enough money:grinpimp:

Tom,

Yes, it can be done. The editor of Peterson's 4Wheel & Off-Road has a 455 in his WWII jeep (a Ford GPW) with a SM420 transmission. So, if you can find the bell housing that will mate a SM420 to Pontiac 455, then it can be adapted to the Toyota T-case. Others have put big block Chevys and big block Fords in the FJ40. It will just take a bit of work to get it done. Good luck.
 
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damn man i thought my buddies 428 was big in his le mans, that thing is gonna be ridiculously torquey ... it can be done... theres alot of room in the engine compartment of the fj40, theres a guy in the 60's tech whos done the 502 big block and i honestly think that the 40 and 60 have a comparable sized engine compartment. for what its worth the only limitations in the project is your skill...
 
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One other thing that I forgot. If you use an aluminum manifold on that engine, it will weigh less than an all cast iron small block Chevy. GM has a group of engines that use what is called, IIRC, investment cast blocks. These are the BOP (Buick, Olds, Pontiac) 455 and Cadilac 472 and 500. All of these engines in stock trim weigh slightly more that the SBC. If you use an aluminum manifold they weigh less than the SBC and if you add aluminum heads, well you get the idea. And yes, there is a cruiser out there with a Cady 500 in it. I saw an article on it in a 4x4 magazine.

The BOP 400 big block might also be in this group, but I'm certain if it is part of this group of engines.
 
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if you have the stock 3 speed all you need is an olds or pontiac standard shift bellhousing and the 3 speed spacer to make it bolt up. use the gto flywheel with gm clutch parts. you will need a rear crossmember and have to make motor mounts i used a truck radiator but maybey a toyota 4 core would work not sure .mine was a 455 super duty with a tripower on it ran it for several years then went to 501 caddy uses the same bell housing not any harder than puting in a chevy except its faster good luck
 
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Pontiac engines make great offroad torque and is a fairly easy swap.
I have run a Pontiac 350 for years and next week I'm swaping the 350 for a balanced 455 that I just finished building last week.
I have run the 350 along side several 350 SB Chevy Cruisers and none of them have been able to lug down like my Pontiac 350 can. It will still pull, down to 400 RPM before it dies because of the longer stroke and longer rod make for more torque.
The Engine in stock form is heavier than a small block chevy but lighter than a big block but will make up for the weight with the torque.

All you will need is a BOP bell housing and you can bolt up a SM420. The clutch fork may have to be shortened, mine did and its on the drivers side along with the starter.
You will also need an angled oil filter mount if you have a straight one on the engine now to get clearance from the frame
They lend themselfs well to home made engine mounts but don't work very good with headers. I have always had to use the stock exhaust manifolds because the width of the heads places them just inside of the frame and not enough room for the shorties.
I was able to make my own mount and mount a York compressor
The 350 worked well with the stock cruiser radiator but last fall when I started building the 455 I also installed an aluminun 2 core 26X19 figuring the 455 will take a little more.
The only negitive is you will not be able to buy bolt on parts for the Pontiac swap you will have to build everything but in my opinion that is the not so bad.
 
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gto and olds use the same bolt pattern as chevy you can use the chevy kit to put in the pontiac except motor mounts. hooking up carb and gauges is same as any gm. basicly it will bolt up to the stock tranny t case if you go to the sm 420 then your into a whole new ball game need more adapters and a lot more money. on the 3 speed you can switch front and rear d shafts for engine position also pilot bearing is the same good luck
 
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Once you get a BOP belhousing then you will be able to bolt up a "gm" tranny like a SM420 or 465, you may even be able to use an nv4500, I'm not sure if the GM trannys changed bolt paterns in the later years.


Pontiac made a 326, 350, 389, 400, 421, 428, and 455, no 426, after 1960 they even had a couple more sizes prior to 1960 but nothing bigger than the 370. They all share the same block exterior dimensions and there is no Big Block or Small Block, even though some people refer to the 421,428 and 455 as a big block, the only diference is the mains go from 3 in to 3.25 no difference in the blocks. Thats how I'm able to swap my 350 with my 455 so easily.
Pontiac engines were known for there torque due to the long stroke long rod, (6.625 in compared to the SB Chevy 5.7), combinations even the 326 shared the same stroke as the 400, (3.75in).


Pic of the 455 ready for the swap
Specs
455 bored 40 over decked and line bored
Crank turned and balanced
Foraged flattop pistons and rebuilt rods with ARP bolts also balanced
Later model 6x 400 heads to give me 9.25 to one compression
Aluminum Rollor rockers
Gear drive
Ram Air III cam (rated for 360 horses in the 400) tried not to get to wild here still wanted the stump pulling low RPM torque
DSC00445.jpg
 
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Ahh, finally an engine swap I can really dig! I grew up in a Pontiac family where tri-power and super duty went along with pass the potatoes and meatloaf!!
There's nothing like the torque of a poncho powered car!
Now I'm thinking of pulling that poncho out from under the work bench and finding a new donor truck!!!
 
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426 was a typo seems like nobody asked this poor guy what tranny he was running all anyone did is say if you do this and this and this for general use there is nothing wrong with the stock tranny it will hold up to a lot of street racing good luck
 
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Bandit:

Might I suggest fully boxing in your frame and adding 1/4 inch crossmembers where ever possible. With that much torque you are going to twist the holyshoe out of your frame.

Good Luck.
 
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..... Ram Air III cam (rated for 360 horses in the 400) tried not to get to wild here still wanted the stump pulling low RPM torque

If you want more bottom end torque, have you thought about advancing the cam two or four degrees?

It will cut some high rpm torque, but that would be in the 5000 to 6000+ rpm range (depending on the cam), and most FJ40's with stock gearing will need 3000 to 3300 at freeway speeds, well under that.

It's a good tradeoff. If I have to change the waterpump out on my 350, I'm going to advance the cam on it.

One caveat - if you have a high lift cam and high compression pistons (popups or flat tops with small valve eyebrows), and especially with oversize valves, you need to check for piston clearance. I have yet to see a mild to medium cam in a stock or mildly warmed engine that had clearance issues, though.
 
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shelfboy1
Not trying to bust your balls just tring to keeping the facts straight
Brian in Oregan
I thought long and hard about which cam to use and I also considered advancing when I finaly relized I'll have more torque than I can use with the cam set straight up Due to 455 cubic inches. Actually the cam I'm using is a stock grind and lends itself well to pump gas due to the late intake close (bleeds off some of the cylinder pressure at low rpm's) and I'll be running 9.25 compression on a large bore with Iron heads. I was a little worried that I would not be able to burn 87 from the pump and advancing the cam would make it worse.
Steve
 

MoGas

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gto and olds use the same bolt pattern as chevy you can use the chevy kit to put in the pontiac except motor mounts.

Not even close.

The Chevrolet bell housing is independent of all other GM cars up to the mid 80's when GM made the "corporate" 350 (Chevy). Pontiac, Oldsmobile, Buick and Cadillac share the same bell housing pattern from mid 60's to mid 80's.

TCI makes an adapter for Chevy to BOP trans and I would bet that someone makes an adapter to go from BOP engine to a Chevy trans then an adapter to the Toyota T case. Not gonna be cheap to do all this, but man the stump pulling torque...........

Here is a universal GM bell housing to mate to a TH-350 if you want to go the auto route.

Dave

Dave
 

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