How far can you overbore a 2.25 diesel.

[Tank]

Do the 2.25 Diesel engines have bore sleeves, what is the maximum oversize bore, if they have sleeves can they be bored in place, Regards Frank.

[JDNSW]

The 2.25 does not have sleeves (the earlier 2.0 had wet sleeves). According to the book the maximum oversize is 1mm, anything over that needs sleeves.

John

[incisor]

you can buy up to +40thou pistons etc off the shelf i believe.

[Tank]

The 2.25 does not have sleeves (the earlier 2.0 had wet sleeves). According to the book the maximum oversize is 1mm, anything over that needs sleeves.

John
John, 1mm = ?? thou, dont have a conversion table and I cant find my feeler guages, Regards frank.

[Tank]

you can buy up to +40thou pistons etc off the shelf i believe.
Incisor, I've my eye on a set at the moment, was worried that it may have sleeves, Regards Frank.

[Tank]

The 2.25 does not have sleeves (the earlier 2.0 had wet sleeves). According to the book the maximum oversize is 1mm, anything over that needs sleeves.

John
John, another one, would there be much of an increase in compression ratio with a 1mm overbore, with the larger swept volume being compressed into the same size combustion chamber (or area), Regards Frank.

[JDNSW]

John, another one, would there be much of an increase in compression ratio with a 1mm overbore, with the larger swept volume being compressed into the same size combustion chamber (or area), Regards Frank.

1. 1mm = .040in

2. According to my calculations the swept volume will be increased by just over 1%, so the compression ratio will increase in the same proportion - i.e. from 23 to about 23.25. I do not think I would worry about the effect of this - in theory it ups the stress on everything by the same amount and improves efficiency by the same amount - but 1% is well within safety margins for everything.

John