Ok, I have been through the mill talking with mechanics, engine shops,
machine shops, and Hesco regarding this question.

My 258 short block is at .040 over bore. I'm getting ready to take it to a
guy for a rebuild to get this puppy back on the road. It will be configured
with the 4.0L head and the Mopar MPI kit at completion.

A lot of you have seen my cylinders posted on the web and note they do not
have a ring ridge so there is a possibility they may not need a bore to .060
over but here's the question, if they do:

I have been told by several mechanics that .060 over will cause the engine
to run hot or hotter than normal.
I checked with JeepsRUs and they said .060 will be no problem even with the
4.0L head
I checked with Hesco and they said the same, no problem.
I just talked to a engine remanufacture shop in LA who told me they don't
send out anything over .030 because it will run hot.


Am I making myself stupid over this? Why is there no consistency with this
question?

Bottom line, will it run hot with .060 over and degrade the life of the
engine quicker?

Thanks,

 

I've never heard it will run too hot, but wouldn't running anything
over thirty for fear the cylinder would blow out, it's just too thin.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

William Oliveri wrote:
>
> Ok, I have been through the mill talking with mechanics, engine shops,
> machine shops, and Hesco regarding this question.
>
> My 258 short block is at .040 over bore. I'm getting ready to take it to a
> guy for a rebuild to get this puppy back on the road. It will be configured
> with the 4.0L head and the Mopar MPI kit at completion.
>
> A lot of you have seen my cylinders posted on the web and note they do not
> have a ring ridge so there is a possibility they may not need a bore to .060
> over but here's the question, if they do:
>
> I have been told by several mechanics that .060 over will cause the engine
> to run hot or hotter than normal.
> I checked with JeepsRUs and they said .060 will be no problem even with the
> 4.0L head
> I checked with Hesco and they said the same, no problem.
> I just talked to a engine remanufacture shop in LA who told me they don't
> send out anything over .030 because it will run hot.
>
> Am I making myself stupid over this? Why is there no consistency with this
> question?
>
> Bottom line, will it run hot with .060 over and degrade the life of the
> engine quicker?
>
> Thanks,

 

I've never heard it will run too hot, but wouldn't running anything
over thirty for fear the cylinder would blow out, it's just too thin.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

William Oliveri wrote:
>
> Ok, I have been through the mill talking with mechanics, engine shops,
> machine shops, and Hesco regarding this question.
>
> My 258 short block is at .040 over bore. I'm getting ready to take it to a
> guy for a rebuild to get this puppy back on the road. It will be configured
> with the 4.0L head and the Mopar MPI kit at completion.
>
> A lot of you have seen my cylinders posted on the web and note they do not
> have a ring ridge so there is a possibility they may not need a bore to .060
> over but here's the question, if they do:
>
> I have been told by several mechanics that .060 over will cause the engine
> to run hot or hotter than normal.
> I checked with JeepsRUs and they said .060 will be no problem even with the
> 4.0L head
> I checked with Hesco and they said the same, no problem.
> I just talked to a engine remanufacture shop in LA who told me they don't
> send out anything over .030 because it will run hot.
>
> Am I making myself stupid over this? Why is there no consistency with this
> question?
>
> Bottom line, will it run hot with .060 over and degrade the life of the
> engine quicker?
>
> Thanks,

 

I've never heard it will run too hot, but wouldn't running anything
over thirty for fear the cylinder would blow out, it's just too thin.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

William Oliveri wrote:
>
> Ok, I have been through the mill talking with mechanics, engine shops,
> machine shops, and Hesco regarding this question.
>
> My 258 short block is at .040 over bore. I'm getting ready to take it to a
> guy for a rebuild to get this puppy back on the road. It will be configured
> with the 4.0L head and the Mopar MPI kit at completion.
>
> A lot of you have seen my cylinders posted on the web and note they do not
> have a ring ridge so there is a possibility they may not need a bore to .060
> over but here's the question, if they do:
>
> I have been told by several mechanics that .060 over will cause the engine
> to run hot or hotter than normal.
> I checked with JeepsRUs and they said .060 will be no problem even with the
> 4.0L head
> I checked with Hesco and they said the same, no problem.
> I just talked to a engine remanufacture shop in LA who told me they don't
> send out anything over .030 because it will run hot.
>
> Am I making myself stupid over this? Why is there no consistency with this
> question?
>
> Bottom line, will it run hot with .060 over and degrade the life of the
> engine quicker?
>
> Thanks,

 

I've never heard it will run too hot, but wouldn't running anything
over thirty for fear the cylinder would blow out, it's just too thin.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

William Oliveri wrote:
>
> Ok, I have been through the mill talking with mechanics, engine shops,
> machine shops, and Hesco regarding this question.
>
> My 258 short block is at .040 over bore. I'm getting ready to take it to a
> guy for a rebuild to get this puppy back on the road. It will be configured
> with the 4.0L head and the Mopar MPI kit at completion.
>
> A lot of you have seen my cylinders posted on the web and note they do not
> have a ring ridge so there is a possibility they may not need a bore to .060
> over but here's the question, if they do:
>
> I have been told by several mechanics that .060 over will cause the engine
> to run hot or hotter than normal.
> I checked with JeepsRUs and they said .060 will be no problem even with the
> 4.0L head
> I checked with Hesco and they said the same, no problem.
> I just talked to a engine remanufacture shop in LA who told me they don't
> send out anything over .030 because it will run hot.
>
> Am I making myself stupid over this? Why is there no consistency with this
> question?
>
> Bottom line, will it run hot with .060 over and degrade the life of the
> engine quicker?
>
> Thanks,

 

"William Oliveri" <wuji@bigvalley.net> wrote in message
news:c5hrvp$1ui58$1@ID-193866.news.uni-berlin.de...
> Ok, I have been through the mill talking with mechanics, engine shops,
> machine shops, and Hesco regarding this question.
>
> My 258 short block is at .040 over bore. I'm getting ready to take it to
a
> guy for a rebuild to get this puppy back on the road. It will be
configured
> with the 4.0L head and the Mopar MPI kit at completion.
>
> A lot of you have seen my cylinders posted on the web and note they do not
> have a ring ridge so there is a possibility they may not need a bore to
..060
> over but here's the question, if they do:
>
> I have been told by several mechanics that .060 over will cause the engine
> to run hot or hotter than normal.
> I checked with JeepsRUs and they said .060 will be no problem even with
the
> 4.0L head
> I checked with Hesco and they said the same, no problem.
> I just talked to a engine remanufacture shop in LA who told me they don't
> send out anything over .030 because it will run hot.
>
>
> Am I making myself stupid over this? Why is there no consistency with
this
> question?
>
> Bottom line, will it run hot with .060 over and degrade the life of the
> engine quicker?
>
> Thanks,
>

The engine won't run hotter because of this. Think of it this way: your
engine is at .040 overbore now. Going to .060 is only .010 per side of the
cylinder. The average human hair is .004. Many of the newer engines are
designed with thinner cylinder wall castings to save weight, but at the
expense of not being able to bore the block as much, if at all. The 32 valve
Cadillac Northstar engine is one that is not recommended to be overbored at
all, and some of the 4.0 Jeep engines being made into stroker engines are
being bored out .120 (after sonic testing). If you are concerned about it,
you can pay someone to sonic check the block for cylinder wall thickness,
but in all honesty, a 9-1 compression 258 isn't going to have a problem with
a .060 overbore.

Chris

 

"William Oliveri" <wuji@bigvalley.net> wrote in message
news:c5hrvp$1ui58$1@ID-193866.news.uni-berlin.de...
> Ok, I have been through the mill talking with mechanics, engine shops,
> machine shops, and Hesco regarding this question.
>
> My 258 short block is at .040 over bore. I'm getting ready to take it to
a
> guy for a rebuild to get this puppy back on the road. It will be
configured
> with the 4.0L head and the Mopar MPI kit at completion.
>
> A lot of you have seen my cylinders posted on the web and note they do not
> have a ring ridge so there is a possibility they may not need a bore to
..060
> over but here's the question, if they do:
>
> I have been told by several mechanics that .060 over will cause the engine
> to run hot or hotter than normal.
> I checked with JeepsRUs and they said .060 will be no problem even with
the
> 4.0L head
> I checked with Hesco and they said the same, no problem.
> I just talked to a engine remanufacture shop in LA who told me they don't
> send out anything over .030 because it will run hot.
>
>
> Am I making myself stupid over this? Why is there no consistency with
this
> question?
>
> Bottom line, will it run hot with .060 over and degrade the life of the
> engine quicker?
>
> Thanks,
>

The engine won't run hotter because of this. Think of it this way: your
engine is at .040 overbore now. Going to .060 is only .010 per side of the
cylinder. The average human hair is .004. Many of the newer engines are
designed with thinner cylinder wall castings to save weight, but at the
expense of not being able to bore the block as much, if at all. The 32 valve
Cadillac Northstar engine is one that is not recommended to be overbored at
all, and some of the 4.0 Jeep engines being made into stroker engines are
being bored out .120 (after sonic testing). If you are concerned about it,
you can pay someone to sonic check the block for cylinder wall thickness,
but in all honesty, a 9-1 compression 258 isn't going to have a problem with
a .060 overbore.

Chris

 

"William Oliveri" <wuji@bigvalley.net> wrote in message
news:c5hrvp$1ui58$1@ID-193866.news.uni-berlin.de...
> Ok, I have been through the mill talking with mechanics, engine shops,
> machine shops, and Hesco regarding this question.
>
> My 258 short block is at .040 over bore. I'm getting ready to take it to
a
> guy for a rebuild to get this puppy back on the road. It will be
configured
> with the 4.0L head and the Mopar MPI kit at completion.
>
> A lot of you have seen my cylinders posted on the web and note they do not
> have a ring ridge so there is a possibility they may not need a bore to
..060
> over but here's the question, if they do:
>
> I have been told by several mechanics that .060 over will cause the engine
> to run hot or hotter than normal.
> I checked with JeepsRUs and they said .060 will be no problem even with
the
> 4.0L head
> I checked with Hesco and they said the same, no problem.
> I just talked to a engine remanufacture shop in LA who told me they don't
> send out anything over .030 because it will run hot.
>
>
> Am I making myself stupid over this? Why is there no consistency with
this
> question?
>
> Bottom line, will it run hot with .060 over and degrade the life of the
> engine quicker?
>
> Thanks,
>

The engine won't run hotter because of this. Think of it this way: your
engine is at .040 overbore now. Going to .060 is only .010 per side of the
cylinder. The average human hair is .004. Many of the newer engines are
designed with thinner cylinder wall castings to save weight, but at the
expense of not being able to bore the block as much, if at all. The 32 valve
Cadillac Northstar engine is one that is not recommended to be overbored at
all, and some of the 4.0 Jeep engines being made into stroker engines are
being bored out .120 (after sonic testing). If you are concerned about it,
you can pay someone to sonic check the block for cylinder wall thickness,
but in all honesty, a 9-1 compression 258 isn't going to have a problem with
a .060 overbore.

Chris

 

"William Oliveri" <wuji@bigvalley.net> wrote in message
news:c5hrvp$1ui58$1@ID-193866.news.uni-berlin.de...
> Ok, I have been through the mill talking with mechanics, engine shops,
> machine shops, and Hesco regarding this question.
>
> My 258 short block is at .040 over bore. I'm getting ready to take it to
a
> guy for a rebuild to get this puppy back on the road. It will be
configured
> with the 4.0L head and the Mopar MPI kit at completion.
>
> A lot of you have seen my cylinders posted on the web and note they do not
> have a ring ridge so there is a possibility they may not need a bore to
..060
> over but here's the question, if they do:
>
> I have been told by several mechanics that .060 over will cause the engine
> to run hot or hotter than normal.
> I checked with JeepsRUs and they said .060 will be no problem even with
the
> 4.0L head
> I checked with Hesco and they said the same, no problem.
> I just talked to a engine remanufacture shop in LA who told me they don't
> send out anything over .030 because it will run hot.
>
>
> Am I making myself stupid over this? Why is there no consistency with
this
> question?
>
> Bottom line, will it run hot with .060 over and degrade the life of the
> engine quicker?
>
> Thanks,
>

The engine won't run hotter because of this. Think of it this way: your
engine is at .040 overbore now. Going to .060 is only .010 per side of the
cylinder. The average human hair is .004. Many of the newer engines are
designed with thinner cylinder wall castings to save weight, but at the
expense of not being able to bore the block as much, if at all. The 32 valve
Cadillac Northstar engine is one that is not recommended to be overbored at
all, and some of the 4.0 Jeep engines being made into stroker engines are
being bored out .120 (after sonic testing). If you are concerned about it,
you can pay someone to sonic check the block for cylinder wall thickness,
but in all honesty, a 9-1 compression 258 isn't going to have a problem with
a .060 overbore.

Chris

 

And after all this, I am guessing that until someone A) funds a
scientific study, or B) you take the plunge, no one will know, so
follow your gut man. Just have the spare $$ to pick up a used or
rebuilt motor after the fact, in case it all goes south.

--
--
Joe Pribe
NC
jpribe 'at' nc.rr.com <you know the drill
jegp 'at' hotmail.com < at is really @
---- I Love My O|||||||O TJ



"c" <c@me.org> wrote in message
news:e80fc.45019$YC5.44874@twister.rdc-kc.rr.com...
|
| "William Oliveri" <wuji@bigvalley.net> wrote in message
| news:c5hrvp$1ui58$1@ID-193866.news.uni-berlin.de...
| > Ok, I have been through the mill talking with mechanics, engine
shops,
| > machine shops, and Hesco regarding this question.
| >
| > My 258 short block is at .040 over bore. I'm getting ready to
take it to
| a
| > guy for a rebuild to get this puppy back on the road. It will be
| configured
| > with the 4.0L head and the Mopar MPI kit at completion.
| >
| > A lot of you have seen my cylinders posted on the web and note
they do not
| > have a ring ridge so there is a possibility they may not need a
bore to
| .060
| > over but here's the question, if they do:
| >
| > I have been told by several mechanics that .060 over will cause
the engine
| > to run hot or hotter than normal.
| > I checked with JeepsRUs and they said .060 will be no problem even
with
| the
| > 4.0L head
| > I checked with Hesco and they said the same, no problem.
| > I just talked to a engine remanufacture shop in LA who told me
they don't
| > send out anything over .030 because it will run hot.
| >
| >
| > Am I making myself stupid over this? Why is there no consistency
with
| this
| > question?
| >
| > Bottom line, will it run hot with .060 over and degrade the life
of the
| > engine quicker?
| >
| > Thanks,
| >
|
| The engine won't run hotter because of this. Think of it this way:
your
| engine is at .040 overbore now. Going to .060 is only .010 per side
of the
| cylinder. The average human hair is .004. Many of the newer engines
are
| designed with thinner cylinder wall castings to save weight, but at
the
| expense of not being able to bore the block as much, if at all. The
32 valve
| Cadillac Northstar engine is one that is not recommended to be
overbored at
| all, and some of the 4.0 Jeep engines being made into stroker
engines are
| being bored out .120 (after sonic testing). If you are concerned
about it,
| you can pay someone to sonic check the block for cylinder wall
thickness,
| but in all honesty, a 9-1 compression 258 isn't going to have a
problem with
| a .060 overbore.
|
| Chris
|
|