Small block... buick? Oldsmobile? PONTIAC?

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AuroraGirl

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Soooo, have any of you guys taken the small blocks from the other divisions and put them in squares? They all came factory with TH350 and TH400s(albeit in sedans,coupes, hatches, etc) but Im sure they could be fitted with proper mounting. Not like the trucks are simple and most capable of changed bracket systems.
 

Keith Seymore

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Certainly been done (...not by me...).

My only observation is that the three that you have listed (Buick, Olds, Pontiac) have a unique bellhousing bolt pattern and would need an adapter plate if coupled to the more available Chevy TH350 or TH400.

K
 

Blue Ox

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The early diesel trucks had 5.7L Oldsmobile diesels with, naturally, a BOP bellhousing transmission. When the Olds diesel got too difficult to deal with a lot of trucks got gas engine conversions but usually needed an Olds gas engine to match the transmission. If you get an engine and transmission together it would solve that problem.

If you do a search, someone here was putting Olds 455s in them. Talk about an upgrade!
 

TubeTruck

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Back in the day.. My buddy's dad took a Suburban frame, cut it down and put his '83 Ramcharger body on it and ran an Olds 455 under the hood, lol. My buddy has it now.
 

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I sold a 350 Buick engine that I had got it balanced, after the car got wrecked by a previous GF.
Sold it to a friend and He stuffed that engine into His SB Chevy pickup. He said best running unit He ever owned.
 

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Anything can be done really, though there are some slight differences it won't just drop right in. Different mounts and stuff. Pretty sure BPO starters are in the wrong spot, etc

I personally love me a pontiac engine
 
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AuroraGirl

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I sold a 350 Buick engine that I had got it balanced, after the car got wrecked by a previous GF.
Sold it to a friend and He stuffed that engine into His SB Chevy pickup. He said best running unit He ever owned.
I must admit..l the amount of rigging, lack of care, gas and coolant leak, etc that my electra has and it sad in a shed for 30 years... purs like a kitten.
 

MrMarty51

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I must admit..l the amount of rigging, lack of care, gas and coolant leak, etc that my electra has and it sad in a shed for 30 years... purs like a kitten.
The wifey took a liking to a non running 88 Buick Century. New fuel pump and it has been a very dependable car. She drives it every day.
It has a 2.8 V6, I must say that must be the crappiest designed engine any manufacturer has ever come up with. Constantly messing with oil leaks, not enough room to really tell where they are coming from. It is either the back of the intake manifold or the oil pump drive adapter. I dont know haow many times I have had those two apart, not a real nice task pulling the lower intake manifold, it incorporates the intake runners into the heads, not a simple set it on and go like the Chevy V8s.
I finally give up on the oil leaks, check the level about every two to three weeks and add a quart or less. It does make a mess on the gravel driveway, especially in the winter when she fires it up, lets it idle for fifteen minutes or more while she is getting ready to take the dog for a run or to head to working. LOL
 

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Just FYI, there is "Unicase" version of the TH350 that works with BOP and Chevy. I have one in my truck, but I don't know what it originally came from. Everything behind the "bellhousing" is the same as a regular Chevy TH350.

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1987 GMC Jimmy

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The wifey took a liking to a non running 88 Buick Century. New fuel pump and it has been a very dependable car. She drives it every day.
It has a 2.8 V6, I must say that must be the crappiest designed engine any manufacturer has ever come up with. Constantly messing with oil leaks, not enough room to really tell where they are coming from. It is either the back of the intake manifold or the oil pump drive adapter. I dont know haow many times I have had those two apart, not a real nice task pulling the lower intake manifold, it incorporates the intake runners into the heads, not a simple set it on and go like the Chevy V8s.
I finally give up on the oil leaks, check the level about every two to three weeks and add a quart or less. It does make a mess on the gravel driveway, especially in the winter when she fires it up, lets it idle for fifteen minutes or more while she is getting ready to take the dog for a run or to head to working. LOL

I like my 3.1 as far as white bread/vanilla GM engines go. It sat for 15 years, doesn’t leak much of anything ever. I guess I got lucky, and that could easily change tomorrow, but they said that drive adapter o ring was the real kicker on these. I’ve got about 6000 miles on it, about 193K total. Jeez, I don’t even want to think about having to pull the lower intake... Now the 440-T4 leaks somewhere to a certain point, about a pint, and then stops. My guess is dipstick hat seal/detent cable grommet or shift lever seal, but I haven’t even looked.

To the OP, I really like the Small Block Buick from a design standpoint. They really put everything in the right place on those. I don’t know if I’d go to the trouble of putting one in something outside of a Buick, but I’d definitely buy a Buick just to get in on the action.
 
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AuroraGirl

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I like my 3.1 as far as white bread/vanilla GM engines go. It sat for 15 years, doesn’t leak much of anything ever. I guess I got lucky, and that could easily change tomorrow, but they said that drive adapter o ring was the real kicker on these. I’ve got about 6000 miles on it, about 193K total. Jeez, I don’t even want to think about having to pull the lower intake... Now the 440-T4 leaks somewhere to a certain point, about a pint, and then stops. My guess is dipstick hat seal/detent cable grommet or shift lever seal, but I haven’t even looked.

To the OP, I really like the Small Block Buick from a design standpoint. They really put everything in the right place on those. I don’t know if I’d go to the trouble of putting one in something outside of a Buick, but I’d definitely buy a Buick just to get in on the action.
Yeah. For someone my height a small block buick is way more convenient to work on. everything is closer to the front of the engine like distributor and dipstick(to be fair, no hard on my square if it werent for the 4wd lift.)
 

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Soooo, have any of you guys taken the small blocks from the other divisions and put them in squares? They all came factory with TH350 and TH400s(albeit in sedans,coupes, hatches, etc) but Im sure they could be fitted with proper mounting. Not like the trucks are simple and most capable of changed bracket systems.


Get a 472 from a 1971 Eldorado and that truck will run!
Most owned by people that took care of those Cadillac autos.
There was a company that made mounts for them and other necessary items.
They even had custom flywheels so that you could mount manual transmissions to them.
 

Ricko1966

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A cutlass,a chevelle,a grand prix and a transam, but haven't done a square body.Yet! But all of them were easy peasy.The reason for the bastard swaps I was young and broke,all done from age15-25.Like the cutlass it had and needed a olds 350 found a whole cheap pontiac big block wagon, pulled the engine and trans dropped it in accessories, trans mission, pontiac frame mounts. Non of them were hard.Think about it as example, GM A body line( Skylark,Cutlass,Chevelle,Grand Prix) all the same frames but different engines in each.All those engines are very similiar in dimensions and mount locations that's why GM could use the same frame for all 4.Only thing special was re routing wiring , and hoses and some times have a driveshaft shortened.Ive since learned how to shorten them .FWIW a friend had a 455 Buick in a c10 my GM swaps BB pontiac to Cutlass, 455 Buick to Trans Am,350 Chevy to Grand Prix,455 Olds to Chevelle.All on factory mounts factory oil pans etc. If I was building a Mud Truck I do a 455 Buick in a Heart beat they are light as a sbc and torque for days.I worked with a guy did a 500 Caddy to C10 it was more of a Pita because the interchangeable parts weren't there.Tom had to order or search for everything.
 
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Bennyt

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Get a 472 from a 1971 Eldorado and that truck will run!
Most owned by people that took care of those Cadillac autos.
There was a company that made mounts for them and other necessary items.
They even had custom flywheels so that you could mount manual transmissions to them.


This is what I plan to do on the next truck. Cad 472/500 are incredible motors. Small/ lightweight, probably smoother than an LS. You can build a very streetable and reliable 540ci version that makes 650 plus HP/TQ and cruise it all day. A bit expensive to get into them but anything making big power is.
 
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