One way to build a strong Volvo Red Motor (aka B230)
Posted by Ken Lanham on August 21st, 2008
This text is lifted from the my old web page about my 1988 Volvo station wagon. I made some updates and completed the text so it now has pretty complete information needed to assemble a similar shortblock. I’m re-posting it here for so people can find it easier and search for it on google or turbobricks.com website.
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Shortblock details
This is how you build a strong long stroke Volvo Red Motor
Block
I started with a 1984 B23 block. At the time of assembly, this was considered the strongest foundation to start with. The block is a little heavier than the late blocks due to more iron in some spots, and it also has a forged steel crankshaft that doesn’t come in the later motors. Since then people have proven that the later blocks and cranks are strong enough for just about anything you can throw at them. But I started with the best at the time:
Block Specs:
1984 Volvo B23FT
Bore: 3.800″ (.030″ over)
Deck Height from crank center to top: 9.125″
Crankshaft

The backbone of a strong motor is the crankshaft. I started with a B23 forged crank. My machine shop did an offset grind on the rod journals to use Mitsubishi 4G63 connecting rods. The rod journals now hold the mitsu rods with about .010″ side clearance. Much nicer than the Volvo setup which guides the rods from the piston. The crank was heat treated after grinding. In metric measures, I started with an 80mm stroke Volvo crankshaft and ended up with 88.8mm stroke
Rod Journal dia: 1.771″
Rod Journal width: 1.130″
Pistons
Compression Height: 1.471″
Rings: 1.5mm,1.5mm,3.0mm
Piston Weight: 419g
Piston to Bore clearance: .006″
The rod dimensions are:
Scat Rods for 4G63 Mitsubishi
Length: 5.906
B.E. dia: 1.890
pin bore dia: .827
Big end width: 1.117
Small end width: 1.010
Some pictures of the assembly coming together. The final displacement is roughly 2.65 liters. Enough for some extra low end grunt.





