overbore

[doctorj240]

Am I going to have reliability problems if I get the motor bored over 1mm on a turbo KA? I don't know if this will weaken it so I can't run high boost. I plan on eventually running a good amount of boost but I'm going to build my motor first and see how far NA can take me before I turbo.

[95_240sx]

No, you shouldnt...Although if you are building the engine for NA right now, you should keep it NA. Once you get a lot of air and fuel crammed into that cylinder from the turbo, then it explodes, you wouldnt believe how much pressure and power there is going against those cylinder walls. Just something to think about.

Rick Merina

[Daunttless]

You can overbore 1mm, thats as far as Nissan says you can overbore, but Nissan also says that isn't necessarily safe. : ) .5mm overbore or what not would be alright.

[95_240sx]

Yeah, well what the hell does Nissan know anyways?



Rick

[Zydeco]

how gain in displacment would you get from 1mm overbore?

[Daunttless]

stock displacement is 2389, with a 1mm overbore to 90mm you would displace 2443. So you'd go from a 2.389 liter to a 2.443 liter.

[Zydeco]

sounds like your better off jsut getting a sr210det

[95_240sx]

I wish I had a sr210det

[george]

You can overbore up to 1mm. and as far as cranking up the boost, no problem. i have seen ka's with overbores running 20psi on stock rods and aris low comp pistons. just safe guard aganist detonation with the proper engine managment, intercooler and larger injectors.