bore

[rbates74]

I am told that the 3.0 is essentially a bored out 2.5, is there any room in the stock 2.5 to bore? if so, how far can you safely bore? can you do like they did in the old days and fill water pasages to add strength and then add cooling upgrades?

ive seen postings sugesting to upgrade to the 3.0 but keep the 2.5 heads, if that is feasble I am wondering why I have seen no mention of overboreing

I have a 99 cougar, 2.5l auto, if boreing is not an option, witch donor car makes the most sence / is the simpliest to swap from?

I would like to get my displacement up, cheaply, and then add a nitrous kit
or in the event it can be done, bore out my 2.5 block, put in some better pistons, and add a forced induction unit.

I had even thought about just swapping out the short block for a 3.0 and keeping the rest of the 2.5

my main objective is to get a faster, fun to drive car that my wife can take to the braket races, and still drive to work

[Tygerr]

I think it'd be much cheaper just to buy a used 3.0L from a Taurus then pay a shop to bore you're old 2.5 out.

Read up on the 3L FAQ and other threads. They have a lot of good information.

[DanG]

Nope. Aluminum engines don't work that way. Especially ours, which has cast-in liners. Those that are sleeved after casting have a bit more play, but you can only go about .5mm (.030") before you start to comprimise the integrity of the liner. And aluminum isn't all that great at ring/piston contact.

[nadthomas]

Not that I'm suggesting the the OP goes this route, but didn't JJennings bore out the engine to a 2.8L back in the day.