Converting B5204T to B5234T

jeffsws · Post by **jeffsws** » 13 Jan 2019, 05:11

First of all, please excuse my ignorance.

Italian T5 engines are 2.0 with a shorter stroke of 77 mm compared to 90 mm on the 2.3 engine. I'm not sure what actually determines that. Is the cylinders longer on the 2.3 or is it determined completely by the piston stroke? Which would mean the only difference between the two engines is the crankshaft? My suspicion is that it's not that simple but any insight would be great.

Cheers for the help!

Post by **precopster** » 13 Jan 2019, 05:33

Stroke is totally determined by the crank throw. The longest cylinder in the world still has the same capacity if the same crank is used.

It would be silly for Volvo to have more than 2 different block styles. They have the T5 block and the NA/2.4T block. Heads are shared.

jeffsws · Post by **jeffsws** » 15 Jan 2019, 09:25

I found that the crankshaft and pistons are different. The connecting rod is the same. As is everything else with the possible exception of the flywheel. I need to look more into that.

Post by **precopster** » 16 Jan 2019, 01:06

Best is to find a copy of Vadis or a later Vida version and compare all the parts. Afew years ago I did some digging and found that the 10 valve and 20 valve engines have the same block, conrods and crank.

If you use the formula V=π*R2*h where R is the bore/2 and h is the stroke you can work out the volume of each cylinder and multiply X 5 to get total capacity of the engine.

Once you have determined that bore is the same between Volvo engines they tend to share the block and have different crankshaft if lower capacity

jeffsws · Post by **jeffsws** » 18 Jan 2019, 15:08

Thank you! I did just that and got Vida set up; it appears the flywheel is the same. I've yet to find any other internal engine differences as of yet. However the turbo is smaller - it's a 13g.

Just for reference here are the part numbers:

Crankshaft
2.0 = 9189283
2.3 = 9189284

Neither are available anymore, so I'll need to find one at the junkyard.

Piston kit
2.0 = 272311 (O.S 0.40mm)
2.3 = 272307 (O.S 0.40mm)

Volvo no longer offer any 2.0 piston gear but they do still offer 2.3, so I'm really forced to upgrade if I ever do a full rebuild of the engine. Alternatively, if I decided to keep it 2.0, I'd need to find an aftermarket (or OEM) pistons. I've no idea where I would find them.

Post by **RickHaleParker** » 18 Jan 2019, 19:34

precopster wrote: 16 Jan 2019, 01:06 If you use the formula V=π*R2*h where R is the bore/2 and h is the stroke you can work out the volume of each cylinder and multiply X 5 to get total capacity of the engine.

Displacement = π/4*Bore²*Stroke*Number of cylinders = 0.7854 * Bore²*Stroke*Number of cylinders

The B5204T has a Bore of 81mm, stroke of 77mm and five cylinders.

0.7854 * 81mm²*77mm*5= 1983908.619 mm³ = 1.984 L. Rounds to 2.0 L.

Post by **polskamafia mjl** » 19 Jan 2019, 15:23

RickHaleParker wrote: 18 Jan 2019, 19:34
precopster wrote: 16 Jan 2019, 01:06 If you use the formula V=π*R2*h where R is the bore/2 and h is the stroke you can work out the volume of each cylinder and multiply X 5 to get total capacity of the engine.
Displacement = π/4*Bore²*Stroke*Number of cylinders = 0.7854 * Bore²*Stroke*Number of cylinders

The B5204T has a Bore of 81mm, stroke of 77mm and five cylinders.

0.7854 * 81mm²*77mm*5= 1983908.619 mm³ = 1.984 L. Rounds to 2.0 L.

Those are the same formulas.

Post by **precopster** » 19 Jan 2019, 18:22

Exactly.

Post by **RickHaleParker** » 19 Jan 2019, 20:18

"V=π*R2*h where R is the bore/2 and h is the stroke"

Where R=81mm/2 = 40.5mm, H=71mm & number of cylinders = 5.
V=π*40.5mm*2*71mm*5 = 90336.497mm³ = 0.903L. rounds to 0.9L not 2.0L

If by R2 you meant R^2 or R²

V=π*40.5mm²*71mm*5 = 1829314.059mm³ = 1.829L. Rounds to 1.8L not 2.0L

Post by **precopster** » 20 Jan 2019, 02:05

The keyboard I have doesn't express to the power of, so R squared was what was intended.

I used Google for the formula for volume of a cylinder without testing it.

No harm in correcting though....