Why 2.5

[Alpine]

Was wondering why the 2.5ltr was called a 2.5 when it has 2435cc displacement, so it is really a 2.4?

I think that the turbo AWD was branded as a 2.4 but it's the same engine.

Anyone know?

I assume it's a Volvo engine, and was it new for the 850 or was it carried over from an older model?

I think it was used later by Ford in the Focus ST, but I stand to be corrected.

[Dippydog]

From what I can gather[and I could be wrong so don't take it as gospel]the 5 pot was originally an Audi unit.Who decided to call it a 2.5 I don't know,I've seen early V70's badged as 2.5,my late P1 V70 has no engine size badging on it,and later V70's had 2.4 badging.I think someone,somewhere[U.S.A.?]decided the displacement wasn't close enough to 2500cc for them to be called 2.5 so Volvo then "downsized" it by calling them 2.4 instead although the engines stayed physically the same.I believe you are correct about the engine being used albeit possibly altered in some way in the Focus ST and also in the RS.

[Clan]

Originally Posted by Alpine

Was wondering why the 2.5ltr was called a 2.5 when it has 2435cc displacement, so it is really a 2.4?

I think that the turbo AWD was branded as a 2.4 but it's the same engine.

Anyone know?

I assume it's a Volvo engine, and was it new for the 850 or was it carried over from an older model?

I think it was used later by Ford in the Focus ST, but I stand to be corrected.

these are 2 different capacities :
B5244 = 2435 cc
B5254 = 2521 cc

The 2.5 has 3mm more stroke otherwise they are the same basic engine

[Alpine]

My source was wiki but I've verified it by my handbook.

Mine is the B5254 and its a 2435cc

I can't find a 5244.

all of the other variants are 2435cc or 1984cc, except T5 and R which is the 2.3.

[Alpine]

....just found this link with all of the engine codes

https://en.wikipedia.org/wiki/Volvo_Modular_engine

the B5244 was in the S70 2.5 from 2000 onwards, it replaced the B5254. Both were 2435cc.

[capt jack]

Simples. Volvo wanted to market the car as a 2.5 litre - it sound more powerful. So they started badging and selling the car as a 2.5.

Sadly, the regulatory jobsworths intervened and pointed out that the convention is to round down 2.435 litres to 2.4 litres, rather than round up to 2.5 litres. So the Volvo marketing team had to revise the badging.

Jack

[Clan]

Originally Posted by Alpine

....just found this link with all of the engine codes

https://en.wikipedia.org/wiki/Volvo_Modular_engine

the B5244 was in the S70 2.5 from 2000 onwards, it replaced the B5254. Both were 2435cc.

these are 2 different capacities :
B5244 = 2435 cc
B5254 = 2521 cc

The 2.5 has 3mm more stroke otherwise they are the same basic engine

[Richard_TD]

They aren't the first to overstate engine capacity. Audi's 2.2 five pot was 2144cc and Chrysler claimed that their 928cc engine was a 1.0.

Something I've been wondering is why the T5 is only a 2.3, why didn't they base it on the 2.4/2.5 engine?

[Clan]

Originally Posted by Richard_TD

They aren't the first to overstate engine capacity. Audi's 2.2 five pot was 2144cc and Chrysler claimed that their 928cc engine was a 1.0.

Something I've been wondering is why the T5 is only a 2.3, why didn't they base it on the 2.4/2.5 engine?

Volvo have not overstated capacity , they use the 2.4 badge for the B5244
( 2435 cc )
and the 2.5 badge for the B5254 ( 2521 cc )

The reason the T5 is 2300 is due to the bore being 1mm less than the 2.4 it would have been to make the liners thicker hence stronger , the 2300 was only used for the high boost engine . The 2300 came long before the 2.4 ...

[john.wigley]

Originally Posted by Richard_TD

They aren't the first to overstate engine capacity. Audi's 2.2 five pot was 2144cc and Chrysler claimed that their 928cc engine was a 1.0.

Something I've been wondering is why the T5 is only a 2.3, why didn't they base it on the 2.4/2.5 engine?

Quite so, 'Richard_TD'!

From 1956 until 1964, the Morris Minor '1000' used the 948 cc 'A' series engine, thereby over-stating it's capacity. Later cars were fitted with the larger 1098 cc variant, thus (unusually) understating it; the '1100' being a totally different car altogether!

Regards, John.