Can I turn a 83 motor into an 87

Technically: yes.
Is it a good idea? No.
109 blocks are so easy to come by why bother?
 
300 is too much for an 83 motor. 50 bucks is more like it. Check here on the forum or on e-bay for what you want. Better yet, call some of the Buick specific shops. Cotton's Performance, Nick Micale, Bison.........etc.
 
NY Twin Turbo said:
300 is too much for an 83 motor. 50 bucks is more like it. Check here on the forum or on e-bay for what you want. Better yet, call some of the Buick specific shops. Cotton's Performance, Nick Micale, Bison.........etc.
Click to expand...
Alright I really don't matter either a 109 block or a 231
 
Your answer is No, you cannot turn a 1983 block into a 1986-87 block. You are stuck with the design limitations of the early block.

The 83 block has some differences from the 86-87 blocks. Back in 1983, Buick had issues with head gasket failures. This was not limited to just turbo engines. All V6's had the issue. In 1983, Buick used conventional head bolts and steel shim head gaskets. The threads in the head bolt holes (block side) came all the way up to the deck surface with a small chamfer at the very top.

In starting in 1985 with the VIN code L engine 3.0 MFI. Buick used a steel shim head gasket with TTY head bolts. The head bolt threads were countersunk deeper into the block. Sinking the threads causes less distortion of the deck surface when bolts are tightened.

Starting in 1986, All Buick v6 engines got composite head gaskets, countersunk head bolt threads, and TTY head bolts. The deck height of the block was also reduced to make up the difference from the thicker head gasket.

The 1983 turbo engine WILL have a turbo/4.1 crank. That is the stronger version with rolled fillets on both rod and main journals.
 
turbodave231 said:
Your answer is No, you cannot turn a 1983 block into a 1986-87 block. You are stuck with the design limitations of the early block.

The 83 block has some differences from the 86-87 blocks. Back in 1983, Buick had issues with head gasket failures. This was not limited to just turbo engines. All V6's had the issue. In 1983, Buick used conventional head bolts and steel shim head gaskets. The threads in the head bolt holes (block side) came all the way up to the deck surface with a small chamfer at the very top.

In starting in 1985 with the VIN code L engine 3.0 MFI. Buick used a steel shim head gasket with TTY head bolts. The head bolt threads were countersunk deeper into the block. Sinking the threads causes less distortion of the deck surface when bolts are tightened.

Starting in 1986, All Buick v6 engines got composite head gaskets, countersunk head bolt threads, and TTY head bolts. The deck height of the block was also reduced to make up the difference from the thicker head gasket.

The 1983 turbo engine WILL have a turbo/4.1 crank. That is the stronger version with rolled fillets on both rod and main journals.
Click to expand...
So in other words there junk lol
 
350turboGN said:
Can I turn a 1983 Buick t-type motor into a 1987 grand national motor?
Click to expand...
Of course you can. You would essentially be doing what some of us are doing when we use the production 4.1 blocks. I would use the newer 8445 heads.
 
I would suggest you go to GNTTYPE.org and look up block ID info as well as the actual differences between the years. There really isn't much difference between the blocks other than the main oil gallery on the passengers side being moved towards the outside of the block more, and the deck height. If properly prepped there really shouldn't be any differences between the early and later blocks. Dave will argue with me on this but people have built both and never really had a lot of problems. The head gasket issue was because of the ends of the heads, and so they added a bridge where the water passage is on each end.
 
charlief1 said:
I would suggest you go to GNTTYPE.org and look up block ID info as well as the actual differences between the years. There really isn't much difference between the blocks other than the main oil gallery on the passengers side being moved towards the outside of the block more, and the deck height. If properly prepped there really shouldn't be any differences between the early and later blocks. Dave will argue with me on this but people have built both and never really had a lot of problems. The head gasket issue was because of the ends of the heads, and so they added a bridge where the water passage is on each end.
Click to expand...
Lol Dave said they were different he's right they ain't worth much the guy wants 300$ if I could just find a 87 block that would be cool
 
350turboGN said:
Ya I thought that's what it would be like changeing over a 4.1 block I
Click to expand...
If you're willing to use a 4.1 then you should know that the only difference between one of them and the earlier blocks, is the siamesed cylinders and the bore. And the 4.1 has been into the 10's as well as lower.;) If the early blocks are such "junk", then why do the 4.1 blocks bring a premium.:eek:
 
I never said they were junk. I just would not place a high value on an early 3.8 block. 4.1 have their advantages.....big bore, better breathing, etc.


Sent from my iPhone using Tapatalk
 
charlief1 said:
If you're willing to use a 4.1 then you should know that the only difference between one of them and the earlier blocks, is the siamesed cylinders and the bore. And the 4.1 has been into the 10's as well as lower.;) If the early blocks are such "junk", then why do the 4.1 blocks bring a premium.:eek:
Click to expand...
Than do you think it's worth it?
 
turbodave231 said:
I never said they were junk. I just would not place a high value on an early 3.8 block. 4.1 have their advantages.....big bore, better breathing, etc.


Sent from my iPhone using Tapatalk
Click to expand...
Oh I know what you meant lol I just don't know much about turbo Buick motors I would like to change mine over tho it has a small block Chevy in it an figured a turbo Buick motor would be fun
 
If all Buick V6 blocks were SG1 blocks,I don't think any knowledgeable engine builder would use words like strong or robust to describe one after seeing one for the first time. When viewed from outside of the Buick community,these blocks would fit the description of weak. The two types of block we have here are weak (86-87) and weaker (all earlier). There is a notable difference between the weak and the weaker,or so we assume it's weaker. This difference is easily seen when viewed from the bottom. Because of this easily seen difference,I would guess that the earlier weigh less.

We can countersink the head bolt holes in the deck to help that situation in the weaker and a girdle helps them all. I wonder which blocks would generally fail first when tuned by a very meticulous and experienced tuner that would never allow for detonation. I think we would be surprised to see how equal there strengths might be or,at least,how much power the weaker could safely and consistently make. Then again,this car is all about surprise and has been from the beginning. The biggest surprise is how much power these weak blocks can handle.

I wonder how many blocks would still be with us if they had all had forged cranks in them. I think the forged crank is something that allows us to produce more power while exerting less destructive forces on the block.

Are these blocks weak. In the general scheme of things,I say yes. The question I ask myself is how much abuse do these blocks see that is caused by us or could be lessened or eliminated. I think crank flex and detonation are bigger players here than block choice. I think all of these blocks tolerate more power when they have a forged internally balanced crank in them and I believe this to be the most important part of the mechanical parts chosen.There is another force that a weak block tolerates less than a stronger one and that is the twisting forces that it has to endure when the engine and transmission assembly is held in place toward the front of the engine. This does the same thing to the block as wringing out a wash cloth. A midplate and stock motor mounts would remove this stress from the block. Some Olds guys do this because of their weak blocks. A step that we can all take in this direction is to use the RJC brace and stock motor mounts.
 
Last edited:
Ttype6 said:
If all Buick V6 blocks were SG1 blocks,I don't think any knowledgeable engine builder would use words like strong or robust to describe one after seeing one for the first time. When viewed from outside of the Buick community,these blocks would fit the description of weak. The two types of block we have here are weak (86-87) and weaker (all earlier). There is a notable difference between the weak and the weaker,or so we assume it's weaker. This difference is easily seen when viewed from the bottom. Because of this easily seen difference,I would guess that the earlier weigh less.

We can countersink the head bolt holes in the deck to help that situation in the weaker and a girdle helps them all. I wonder which blocks would generally fail first when tuned by a very meticulous and experienced tuner that would never allow for detonation. I think we would be surprised to see how equal there strengths might be or,at least,how much power the weaker could safely and consistently make. Then again,this car is all about surprise and has been from the beginning. The biggest surprise is how much power these weak blocks can handle.

I wonder how many blocks would still be with us if they had all had forged cranks in them. I think the forged crank is something that allows us to produce more power while exerting less destructive forces on the block.

Are these blocks weak. In the general scheme of things,I say yes. The question I ask myself is how much abuse do these blocks see that is caused by us or could be lessened or eliminated. I think crank flex and detonation are bigger players here than block choice. I think all of these blocks tolerate more power when they have a forged internally balanced crank in them and I believe this to be the most important part of the mechanical parts chosen.There is another force that a weak block tolerates less than a stronger one and that is the twisting forces that it has to endure when the engine and transmission assembly is held in place toward the front of the engine. This does the same thing to the block as wringing out a wash cloth. A midplate and stock motor mounts would remove this stress from the block. Some Olds guys do this because of their weak blocks. A step that we can all take in this direction is to use the RJC brace and stock motor mounts.
Click to expand...
Alright so the block is weaker then 86 87 block so I can build it stronger tho?
 
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