BORED 60 OVER?

[Anonymous]

Does anyone know or could tell me if .60 over would be too much on a 170? What would it be like if it was bored this much? Thanks, bchauto

 

[addo]

60 is pretty much the limit unless you use sonic testing to centre each bore.

It will make less difference from the extra capacity, than other areas of potential gain. By that, I mean stuff like raising the compression ratio or light portwork.

Regards, Adam.

 

[fordconvert]

My 200 came with 60 over pistons in it. I have been told that you need some luck and the right block to get away with it.

 

[Anonymous]

THANKS FOR THE HELP, ANYONE ELSE HAVE ANY INPUT? BCHAUTO

 

[Junk-Falcon]

over the years

 

[Anonymous]

will it help if its bored that much or not?

 

[addo]

It's best to bore little as possible, rarely as possible.

 

[shmoozo]

Does anyone know or could tell me if .60 over would be too much on a 170? What would it be like if it was bored this much? Thanks, bchauto

A wise old machinist/mechanic once gave me a bit of advice -- Never bore an engine block out more than required to clean up the bores and then get the bore size up to the next standard piston size.

In other words, if 0.020 over-stock-sized pistons are the smallest pistons over the stock size pistins you can get and boring the cylinders over by 0.020 will get your bores cleaned up, that's as much as you should go.

My advice? Strip the block, take it yourself to a good local machine shop, and have them take a good look at it. Bring a list of pistons that are available and that you'd want to use making sure it lists all the available overbore sizes. Then let them tell you how little they can overbore and still wind up with clean bores that will fit one of the standard overbore pistons on your list.

Have them overbore the block that much, and assuming it works out correctly order the pistons needed at that point. You might want to ask them for advice about which pistons to use. They probably have some experience in the area.

If you block has never been overbored chances are it won't need anything close to a 0.060 overbore. Chances are a 0.020 or 0.030 overbore will do the job just fine.

 

[HighVolkage]

my 200 is bored .060 :roll: whoops

 

[addo]

My Dad's over 60 and he gets bored sometimes, too.

 

[LEROY POLL]

ADDO


.....I'M OVER 60 AND NEVER BEEN BORED. AN ANSWER TO YOUR LITTLE DOWNUNDER JOKE!

LIVE IN GRACE

LEROY POLL

 

[powerband]

This debate on "OVERBORE" surfaces occasionally and to keep it interesting I'll add my .02 C.

http://fordsix.com/forum/viewtopic.php? ... highlight=

The 250 built in Jack Cliffords shop years ago that I found "mothballed" - that is stored new but never fired until this summer has the 258 Pistons with a .070 overbore. Runs great with no problems after @ 1000 miles. Has incredible torque winding out to 5K conservatively. I find no problems with wide changes of spark advance. I run 92 Octane for the 10:1 CR but have experienced no detonation or pinging . It has a 272 Cam . I run an aftermarket aluminum radiator with electric fan.

Jack Clifford, legendary six cylinder racer, record holder and engine builder's shop, performance built Ford 250 six engine- 10:1 Pistons, Clifford rods, Clifford 272H Cam, line bored & balanced bottom end, Cloyes timing set, Melling pump, Fisher balancer, 1.88 int. valves, Ported and relieved, Offy 3X1 w/3 Holleys, Re-curved distrib., the works, a few mysteries...


Powerband