[joe1l]

How much Horsepower can you expect with a high compression piston. How about torque?
I know there are 12:1, 13.8:1. How much can we expect from these pistons?

 

[PICKLES]

I would just wait for like a 470, 500 or 520 kit on high comp before I did anything like that just to keep my options open. good luck
-peace

 

[86atc250r]

Two things to remember when waiting for overbore "kits" with the 450R:

1.) The 450R cylinder is plated - so you can't just go out and have the cyl bored & slap in a new piston like a 400EX or 250R.

2.) With the 450R, any overbore what-so-ever will raise it above the limits for anything but the open classes in most forms of racing.

These two items will significantly reduce the options that become available for the 450R.

The last thing to think about is - how much power do you really expect to get from a simple overbore? Is it worth the costs of replating, possibly a new cylinder, a high priced custom piston kit, machine work, and thinning your cylinder walls which may adversely affect reliability (to get any significant cc gains, you will have to bore rather large)?

When changing the piston, the bulk of your power increase is going to come from changing the compression, not small increases in bore diameter. In my opinion - staying with the stock bore and increasing the compression a bit is going to be the best option for this engine.

 

[D-RACER]

Originally posted by 86atc250r@Jun 3 2004, 01:14 PM
Two things to remember when waiting for overbore "kits" with the 450R:

1.) The 450R cylinder is plated - so you can't just go out and have the cyl bored & slap in a new piston like a 400EX or 250R. 

2.) With the 450R, any overbore what-so-ever will raise it above the limits for anything but the open classes in most forms of racing.

These two items will significantly reduce the options that become available for the 450R.

The last thing to think about is - how much power do you really expect to get from a simple overbore?  Is it worth the costs of replating, possibly a new cylinder, a high priced custom piston kit, machine work, and thinning your cylinder walls which may adversely affect reliability (to get any significant cc gains, you will have to bore rather large)?

When changing the piston, the bulk of your power increase is going to come from changing the compression, not small increases in bore diameter.  In my opinion - staying with the stock bore and increasing the compression a bit is going to be the best option for this engine.

[snapback]6267[/snapback]​

i was just read around alittle,and was wondering if you guys still feel the same way.............isn't a change of thinking sometimes a good thing....

 

[Trx450always]

wow for a second I thought dez was back, then I read the date. :slap: