which block do I use?

[gsbuick65]

went looking for another block to use, found 2 of the same # 25514290, and a 25524140, which shows to be a 84-87 block. or do I keep looking for a 109 block?

 

[Anthony P]

It depends what you want to do. The "290" block is 1984 vintage, possibly from a normally aspirated engine. The "140" block is 1985 vintage, possibly from a normally aspirated engine although I have seen '85 hot air engines using 140 blocks. The gnttype.org tech articles have a good listing of casting #'s and pics. The "109" blocks were used in 86 and 87 for both turbo and N/A engines. The 109 block has a solid cast lifter valley while the other two have very rough openings for the oil to drain through. Do you want #'s matching for a specific car or just a good block.

 

[gsbuick65]

It depends what you want to do. The "290" block is 1984 vintage, possibly from a normally aspirated engine. The "140" block is 1985 vintage, possibly from a normally aspirated engine although I have seen '85 hot air engines using 140 blocks. The gnttype.org tech articles have a good listing of casting #'s and pics. The "109" blocks were used in 86 and 87 for both turbo and N/A engines. The 109 block has a solid cast lifter valley while the other two have very rough openings for the oil to drain through. Do you want #'s matching for a specific car or just a good block.

well not going to be a race car, but I want to use a good block, will monte carlos use the 109 block? yea i looked at gnttype.org. my 290 block spun #2 cam bearing. but probably from over torqured head bolts

 

[Anthony P]

The 109 block would be the strongest regular production block. Point to note is that the turbo oil return line drains into the front of this block, because these were all intercooled cars. The hot air cars drained the oil back through the intake manifold. So the block choice depends on which setup you are planning.

 

[gsbuick65]

isnt there a non turbo 109 block? im using the hot air set-up, just want to use the best block I can.

 

[Anthony P]

Yes, the 109 block was also used in the '86 and '87 2bbl normally aspirated (N/A) RWD Buick Regals, Olds Cutlass Supreme, and I think Pontiac Grand Prix. If you can find one from these cars (and you are not concerned about matching #'s for model year), this N/A 109 block would be best for a street car. The boss on the front of the lifter valley was never drilled for the oil return and the block was never subjected to boost (or over-boost) stresses.

If you can't put your hands on one of the N/A 109 blocks, any one of the 290, 140, or 329 blocks would suffice...but I would not try to run 500 hp through it. As you know, any modifications above the stock level require planning and usually in concert with other modified components.

On a side note, a mutual friend of mine has some NOS and used hot air parts... from an '85 unused crate engine to complete intake manifold assemblies (with turbo, throttle body, fuel rail/injectors/harness, coilpak/module/plug wires, stainless braided up-pipe, etc. Let me know if I can help you with your rebuild. Good luck.

 

[49-blues]

I have a friend who has a fresh 85 block with a 20 bolt oil pan-same as 6109 blocks-with arp head studs. complete longblock $1300. plus shipping or will help with local delivery.

 

[turbofish38]

Any of those blocks will work for a hot air. Those castings numbers are the same between turbo and NA. The only thing different on a turbo 109 block is the drain back hole drilled on the front. If you use a 109 block make sure you use the IC head gasket and factory torque to yeild head bolts or ARP bolts or studs.

 

[gsbuick65]

found a 140 block, but it uses a 20? bolt oil pan. will everything else bolt to this block.?

 

[Anthony P]

A 140 block with the 20 bolt pan will work fine. It is a later year '85 block as it has the three reinforcing "ribs" cast into the upper valley on the front of the block (whereas the 0329 block used in '84 and part of 85 had no ribs. The two hot air crate engines I listed for sale use the 140 block.

 

[fgordon]

Buick V6 History

Check out this link to identify the blocks. The 290 is a 79 Turbo block and the 140 is a 85 NA Block according to this site.