This is my first post to a newsgroup, so apologies in advance if I fracture
any ethics.
My question is - According to ‘The Book’ it appears that 98 mm is the limit
to expanding the bore. What causes the limitation because if nearly 4mm
more can be found then the 4" piston market (Chevy et al) would be useable?
Depending on the cost of finding those 4mm, this should result in more cost
effective performance gains.
Duncan
1980 XJS v12
Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !
Hi Duncan,
A couple of limitations on bore size.
The first is the cylinder liners must fit into the block.
If you put larger bore liners, the thickness of the metal at the
place where the liner slides into the block becomes weaker as the
bore size gets larger.
I have seen in VW air-cooled where the blocks are “fly cut” to
accommodate larger bores, but there are limits.
Second, are head gasket sealing problems where the sealing rings
start projecting into the bore. Custom head gaskets would need
to be manufactured. BIG BUCKS
Overall I think the main reason for not going the over bore route
is that the engine has got a very short stroke compared to bore
size.
It is easier/cheaper to get more inches by stroking it.
Duncan Wood wrote:
This is my first post to a newsgroup, so apologies in advance if I fracture
any ethics.
My question is - According to ‘The Book’ it appears that 98 mm is the limit
to expanding the bore. What causes the limitation because if nearly 4mm
more can be found then the 4" piston market (Chevy et al) would be useable?
Depending on the cost of finding those 4mm, this should result in more cost
effective performance gains.
Duncan
1980 XJS v12
Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !
Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !