Boring the sr20? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

gsrcamel · 03-16-2002, 12:37 PM

I have seen 240's in some of my mags with the engine swap performed. One of wich was a 2.1 L. I was just wondering if anyone has any suggestive or negative comments about doing this procedure. I am not sure if it was bored and stroked but I like the high revving characteristics of the sr20 and that is probably due to my honda background so that means that I would suggest to my self that I not increase the stroke in the engine to keep it safe at high RPM's. Now to further complicate my question I would just like to ask, is it wize to bore the sr20 block and if so how much can it safely be done. I plan on rebuilding the engine once it gets in the 100,000 mile range and I was just going to get some comments ahead of time on what I should do.

DrDubbleB · 03-16-2002, 12:47 PM

It might have slightly negative aspects in the very long run, down the road, but I highly doubt that you could see any reliability problems for everyday driving.  I think the one you refer to is Non Fujita's 240.  He has a Tomei built SR20 in it.  They do make a kit that you could buy (yes it is a bore/stroke kit) to make it a 2.1 litre engine.  JUN also makes a kit that bores it out to 2.2 litres (which is the one I plan on getting).  The reason why there should be no reliability problems is because you are not touching the block itself, you are just replacing all the parts (Pistons, rods, valves, springs, even the crank, and of course, more).  These parts are made to withstand the added stress.  I think it's worth it, you do keep the high-revving aspect, and you can get more power out of the engine.

gsrcamel · 03-16-2002, 12:54 PM

sounds good but also expensive. What would you think about stock size rods (crower) and bigger pistons from greddy or arias. is it safe or possible to retain the stock crank. I am on a little bit of a budget I would like to rebuild the engine in the 2K range if at all possible. (and make it stronger than factory)

crazycuban · 03-16-2002, 03:20 PM

It's fairly popular among built SR's (not SR's here) to bore it out from 86mm to 87mm, and drop in 300ZX pistons...you don't have to go aftermarket...and most aftermarket manufacturers that make pistons for the SR (i.e. Jun, Greddy, HKS) will have 87mm pistons as well.

mistert · 03-16-2002, 05:32 PM

actually dubbleB all of the 2.1 and 2.2 kits (As far as i know) do require machining of the block to put in the kit. how are you gonna increase bore and stroke with just a crank and stock sized pistons, gotta bore that sucker out some

MeanRex7 · 03-16-2002, 05:55 PM

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (mistert @ Mar. 16 2002,07:32)</td></tr><tr><td id="QUOTE">actually dubbleB all of the 2.1 and 2.2 kits (As far as i know) do require machining of the block to put in the kit. how are you gonna increase bore and stroke with just a crank and stock sized pistons, gotta bore that sucker out some</td></tr></table><span id='postcolor'>
just force the piston in with a hammer, although the pistons will lose, try it about 3 times per cylinder, you should have a nice fit by then. Then buy your 4th piston per cylinder and enjoy.

mistert · 03-16-2002, 05:57 PM

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (MeanRex7 @ Mar. 15 2002,6:55)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (mistert @ Mar. 16 2002,07:32)</td></tr><tr><td id="QUOTE">actually dubbleB all of the 2.1 and 2.2 kits (As far as i know) do require machining of the block to put in the kit. how are you gonna increase bore and stroke with just a crank and stock sized pistons, gotta bore that sucker out some</td></tr></table><span id='postcolor'>
just force the piston in with a hammer, although the pistons will lose, try it about 3 times per cylinder, you should have a nice fit by then. Then buy your 4th piston per cylinder and enjoy.</td></tr></table><span id='postcolor'>
node's one of those guys who tried to shove the square blocks into the round slots

he does happen to like squarepusher

MeanRex7 · 03-16-2002, 05:58 PM

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (mistert @ Mar. 16 2002,07:57)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (MeanRex7 @ Mar. 15 2002,6:55)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (mistert @ Mar. 16 2002,07:32)</td></tr><tr><td id="QUOTE">actually dubbleB all of the 2.1 and 2.2 kits (As far as i know) do require machining of the block to put in the kit. how are you gonna increase bore and stroke with just a crank and stock sized pistons, gotta bore that sucker out some</td></tr></table><span id='postcolor'>
just force the piston in with a hammer, although the pistons will lose, try it about 3 times per cylinder, you should have a nice fit by then. Then buy your 4th piston per cylinder and enjoy.</td></tr></table><span id='postcolor'>
node's one of those guys who tried to shove the square blocks into the round slots

he does happen to like squarepusher</td></tr></table><span id='postcolor'>
what're you talkin bout willis. I like square pusher (listens to vic acid)
You're the one w/ the square dild...OK nevermind, we're getting off topic. Back to the boring!

03-16-2002, 12:37 PM	#1
gsrcamel Leaky Injector Join Date: Jan 2002 Posts: 82 Trader Rating: (0) Feedback Score: 0 reviews	I have seen 240's in some of my mags with the engine swap performed. One of wich was a 2.1 L. I was just wondering if anyone has any suggestive or negative comments about doing this procedure. I am not sure if it was bored and stroked but I like the high revving characteristics of the sr20 and that is probably due to my honda background so that means that I would suggest to my self that I not increase the stroke in the engine to keep it safe at high RPM's. Now to further complicate my question I would just like to ask, is it wize to bore the sr20 block and if so how much can it safely be done. I plan on rebuilding the engine once it gets in the 100,000 mile range and I was just going to get some comments ahead of time on what I should do. __________________ I currently own a 95 Acura Integra GS-R with plans to buy a 240 and throw in a sr20det![br]http://www.angelfire.com/ga4/s14/index.html

03-16-2002, 12:54 PM	#3
gsrcamel Leaky Injector Join Date: Jan 2002 Posts: 82 Trader Rating: (0) Feedback Score: 0 reviews	sounds good but also expensive. What would you think about stock size rods (crower) and bigger pistons from greddy or arias. is it safe or possible to retain the stock crank. I am on a little bit of a budget I would like to rebuild the engine in the 2K range if at all possible. (and make it stronger than factory) __________________ I currently own a 95 Acura Integra GS-R with plans to buy a 240 and throw in a sr20det![br]http://www.angelfire.com/ga4/s14/index.html

03-16-2002, 05:32 PM	#5
mistert Pearl White Mike Join Date: Oct 2001 Location: memphis TN Posts: 908 Trader Rating: (0) Feedback Score: 0 reviews	actually dubbleB all of the 2.1 and 2.2 kits (As far as i know) do require machining of the block to put in the kit. how are you gonna increase bore and stroke with just a crank and stock sized pistons, gotta bore that sucker out some __________________ "He who makes a beast of himself gets rid of the pain of being a man" ~ Samuel Johnson

03-16-2002, 05:57 PM	#7
mistert Pearl White Mike Join Date: Oct 2001 Location: memphis TN Posts: 908 Trader Rating: (0) Feedback Score: 0 reviews	</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (MeanRex7 @ Mar. 15 2002,6:55)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (mistert @ Mar. 16 2002,07:32)</td></tr><tr><td id="QUOTE">actually dubbleB all of the 2.1 and 2.2 kits (As far as i know) do require machining of the block to put in the kit. how are you gonna increase bore and stroke with just a crank and stock sized pistons, gotta bore that sucker out some</td></tr></table><span id='postcolor'> just force the piston in with a hammer, although the pistons will lose, try it about 3 times per cylinder, you should have a nice fit by then. Then buy your 4th piston per cylinder and enjoy.</td></tr></table><span id='postcolor'> node's one of those guys who tried to shove the square blocks into the round slots he does happen to like squarepusher __________________ "He who makes a beast of himself gets rid of the pain of being a man" ~ Samuel Johnson

03-16-2002, 12:47 PM	#2
DrDubbleB Zilvia FREAK! Join Date: Feb 2002 Posts: 1,119 Trader Rating: (0) Feedback Score: 0 reviews	It might have slightly negative aspects in the very long run, down the road, but I highly doubt that you could see any reliability problems for everyday driving.  I think the one you refer to is Non Fujita's 240.  He has a Tomei built SR20 in it.  They do make a kit that you could buy (yes it is a bore/stroke kit) to make it a 2.1 litre engine.  JUN also makes a kit that bores it out to 2.2 litres (which is the one I plan on getting).  The reason why there should be no reliability problems is because you are not touching the block itself, you are just replacing all the parts (Pistons, rods, valves, springs, even the crank, and of course, more).  These parts are made to withstand the added stress.  I think it's worth it, you do keep the high-revving aspect, and you can get more power out of the engine.

03-16-2002, 03:20 PM	#4
crazycuban Zilvia Junkie Join Date: Nov 2001 Posts: 526 Trader Rating: (0) Feedback Score: 0 reviews	It's fairly popular among built SR's (not SR's here) to bore it out from 86mm to 87mm, and drop in 300ZX pistons...you don't have to go aftermarket...and most aftermarket manufacturers that make pistons for the SR (i.e. Jun, Greddy, HKS) will have 87mm pistons as well.

03-16-2002, 05:55 PM	#6
MeanRex7 Join Date: Sep 2001 Posts: 31 Trader Rating: (0) Feedback Score: 0 reviews	</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (mistert @ Mar. 16 2002,07:32)</td></tr><tr><td id="QUOTE">actually dubbleB all of the 2.1 and 2.2 kits (As far as i know) do require machining of the block to put in the kit. how are you gonna increase bore and stroke with just a crank and stock sized pistons, gotta bore that sucker out some</td></tr></table><span id='postcolor'> just force the piston in with a hammer, although the pistons will lose, try it about 3 times per cylinder, you should have a nice fit by then. Then buy your 4th piston per cylinder and enjoy.

03-16-2002, 05:58 PM	#8
MeanRex7 Join Date: Sep 2001 Posts: 31 Trader Rating: (0) Feedback Score: 0 reviews	</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (mistert @ Mar. 16 2002,07:57)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (MeanRex7 @ Mar. 15 2002,6:55)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (mistert @ Mar. 16 2002,07:32)</td></tr><tr><td id="QUOTE">actually dubbleB all of the 2.1 and 2.2 kits (As far as i know) do require machining of the block to put in the kit. how are you gonna increase bore and stroke with just a crank and stock sized pistons, gotta bore that sucker out some</td></tr></table><span id='postcolor'> just force the piston in with a hammer, although the pistons will lose, try it about 3 times per cylinder, you should have a nice fit by then. Then buy your 4th piston per cylinder and enjoy.</td></tr></table><span id='postcolor'> node's one of those guys who tried to shove the square blocks into the round slots he does happen to like squarepusher</td></tr></table><span id='postcolor'> what're you talkin bout willis. I like square pusher (listens to vic acid) You're the one w/ the square dild...OK nevermind, we're getting off topic. Back to the boring!