Boring out KA....? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Muzzy · 02-04-2003, 09:52 PM

has anyone ever bored out a KA??

would this be wise thing to do??

(i know it wouldn't be wise if its bored too much)

*Jeff240sx* · 02-04-2003, 10:16 PM

.040" is about the largest that you want to go, but I believe PSI240SX bored his .050". And boring that little, you aren't increasing the displacement much. I think PSI240SX's car is 2.445L or something. I'm not doing the math right now, but I'm close.
-Jeff

Titan · 02-05-2003, 07:19 AM

If I'm not mistaken, is the KA not bored out to almost max from factory? I recall hearing somewhere that the block was originally smaller.

allmotorKA · 02-05-2003, 01:53 PM

You should be able to bore to the service bore...on the SOHC engine stock bore is 89mm and the service bore is 90mm (thats about .040" over). Not sure what the DOHC specs would be but I assume it is similar. I had my engine bored to 90mm and have no problems...but my engine is not turbo charged. I would be a little more cautious if running high boost is in your plans.

ruf · 02-05-2003, 02:26 PM

A .040 overbore is no problem on a KA-T as long as it's built right.

Muzzy · 02-05-2003, 10:56 PM

more displace ment means more torque right?

off the subject...hey ruf..do u race at Reflex R/C

ruf · 02-06-2003, 12:19 AM

I own Reflex R/C. Have you been there? Wondering if I've seen you.

02-04-2003, 09:52 PM	#1
Muzzy Zilvia FREAK! Join Date: Jan 2003 Location: TX Posts: 1,555 Trader Rating: (0) Feedback Score: 0 reviews	Boring out KA....? has anyone ever bored out a KA?? would this be wise thing to do?? (i know it wouldn't be wise if its bored too much) __________________ lemme have a dollar

02-04-2003, 10:16 PM	#2
Jeff240sx I hate you too... Join Date: Jul 2001 Location: Tampa, FL Age: 42 Posts: 5,828 Trader Rating: (0) Rides Gallery: Jeff240sx Feedback Score: 0 reviews	.040" is about the largest that you want to go, but I believe PSI240SX bored his .050". And boring that little, you aren't increasing the displacement much. I think PSI240SX's car is 2.445L or something. I'm not doing the math right now, but I'm close. -Jeff __________________ Whatup?

02-05-2003, 07:19 AM	#3
Titan Zilvia Junkie Join Date: Apr 2002 Location: Ontario, Canada Posts: 421 Trader Rating: (0) Feedback Score: 0 reviews	If I'm not mistaken, is the KA not bored out to almost max from factory? I recall hearing somewhere that the block was originally smaller. __________________ Sleep Doesn't Drink Beer

02-05-2003, 10:56 PM	#6
Muzzy Zilvia FREAK! Join Date: Jan 2003 Location: TX Posts: 1,555 Trader Rating: (0) Feedback Score: 0 reviews	more displace ment means more torque right? off the subject...hey ruf..do u race at Reflex R/C __________________ lemme have a dollar

02-05-2003, 01:53 PM	#4
allmotorKA Zilvia Member Join Date: Nov 2001 Location: SoCal Posts: 204 Trader Rating: (1) Feedback Score: 1 reviews	You should be able to bore to the service bore...on the SOHC engine stock bore is 89mm and the service bore is 90mm (thats about .040" over). Not sure what the DOHC specs would be but I assume it is similar. I had my engine bored to 90mm and have no problems...but my engine is not turbo charged. I would be a little more cautious if running high boost is in your plans.

02-05-2003, 02:26 PM	#5
ruf Zilvia FREAK! Join Date: Jul 2002 Location: Reflex Racing, Los Angeles,TX Posts: 1,160 Trader Rating: (0) Feedback Score: 0 reviews	A .040 overbore is no problem on a KA-T as long as it's built right.

02-06-2003, 12:19 AM	#7
ruf Zilvia FREAK! Join Date: Jul 2002 Location: Reflex Racing, Los Angeles,TX Posts: 1,160 Trader Rating: (0) Feedback Score: 0 reviews	I own Reflex R/C. Have you been there? Wondering if I've seen you.