Converting a 85 block for an 87???

[Quickturbosix]

What all needs to be done to convert a block from an 85 so it can be used in a 87? Is drilling the oil drain back the only thing? Where exactly is this spot and how hard is it to do this. The block is already built, just a short block.

 

[Dan Thompson]

I'm by no means the expert, but I think the crank and rods are also different (stronger).

Try this website

http://www.gnttype.org/techarea/pictureguides/blocks/8485prodturbo.html

Here is a rebuild site

http://www.gnttype.org/general/rebuild.html

HTH

 

[cool 84]

Same crank, same rods, pistons are slightly different but just as strong. Side by side I couldn't tell a difference in the main webbing between the hotair and 109 block. The lifter valley isn't as pretty and that's about it. To use the IC stuff you need to run the 84/85 steel shim headgaskets to keep the stock compression. There's no boss on the early blocks for the oil return. You could still drill it though but it might be a lot easier to have it dump into the pan.