i have a 98 gsr and im planning on doing a N/A build, and i was wondering if it would make much difference if i bored .20 over to 81.5mm. Im going to give it a fresh hone, so while i was getting that done i figured id get it bored but for the extra money to do that is it really worth it?

 

i'm no expert, but i'm planning on pretty much the same thing for a 96 gsr. I'm starting to get my info together and from what i've read there is no replacement for displacement. But you have to be careful that you don't get your cylinder walls to thin from a larger bore. There is a feature about doing a N/A 150hp/leter in honda tuning lots of good info. check it out

 

yea ive read that lol, but im still trying to figure out if it will make much difference.

 

you should post this on all motor section you will find more help!

 

well u will have to get different pistons. And depending on if you get a higher C/R that will make a difference. But if you stay the same, it will not really be that noticeable. But hey I say go with it. If you already plan on giving the block a nice hone might as well. I mean I'm doing the same thing to my block too. but this well be for a boosted project.

 

if your just going all motor i would go 40. over or 82mm. sleeves willbe more than strong enough for any all motor application and that size. you will have basially a 1.9 liter than. much more noticeable power gain.

 

yea idk about going that far with stock sleeves lol

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by indicajones &raquo;</TD></TR><TR><TD CLASS="quote">if your just going all motor i would go 40. over or 82mm. sleeves willbe more than strong enough for any all motor application and that size. you will have basially a 1.9 liter than. much more noticeable power gain.</TD></TR></TABLE>
no, displacement would still be just under 1800cc with an 82mm bore

going from 81mm to 81.5mm wont give you a lot of noticeable power. but you will have a fresh bore to start with.

 

I've heard too that you can get a little bit more stroke from ls rods and crank. With the longer stroke and the larger bore you should be able to get some power out of it. Also, i've heard if you are building an N/A motor you should be looking for revs too. Anything you can do to increase your redline will give you more hp, i would like to get close to 10 on my rebuild. The hp that will result in building a motor that can rev that high should be more than adiquite. I'm thinking too that the gsr gears are pretty long too, if the tranny could be replace with a closer ratio in gears you should fly. Don't know your budget tho, but that's my plan of attack on a N/A motor.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SleeperGSR &raquo;</TD></TR><TR><TD CLASS="quote">I've heard too that you can get a little bit more stroke from ls rods and crank. With the longer stroke and the larger bore you should be able to get some power out of it. Also, i've heard if you are building an N/A motor you should be looking for revs too. Anything you can do to increase your redline will give you more hp, i would like to get close to 10 on my rebuild. The hp that will result in building a motor that can rev that high should be more than adiquite. I'm thinking too that the gsr gears are pretty long too, if the tranny could be replace with a closer ratio in gears you should fly. Don't know your budget tho, but that's my plan of attack on a N/A motor.</TD></TR></TABLE>

just revving higher than stock wont make more hp. if the cams dont make power past 9k for instance there's no use revving that high.

 

exactley revving higher isnt going to make any more hp unless your cams can handle it, and the gsr tranny has short gears ls has longer gears

 

my bad bout the gears, got things backwards. When i was talking about reving higher i meant building the motor to rev higher and make the hp. I wasn't just going to remove the limiter and hope for the best. Thanks for clearing it up tho, i'll try to be more specific in the future. I'm new here.

 

it is common practice to bore .20 over so you will have a perfectly round cylinder

if you stay at 81mm your bores will be out of round which will result in poor ring sealing and oil consumption power losses

 

when u boring to a bigger size the .20 does really matter that much. if u go na i belive its suppot to be a littel under.im get my block to a 84mm here is the # to the place that is doing its 760-630-0450(its in san diego ca its open from 8-5). the guy there will be able to answer all ur ?

 

It's more for a "fresh start" on the sleeves as opposed to the gain in power.

Sort of how an engine that has 3k miles on it runs more efficiently (and therefore has the ability to make more power) than an engine with 203k on it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by KoalaEatingTree &raquo;</TD></TR><TR><TD CLASS="quote">It's more for a "fresh start" on the sleeves as opposed to the gain in power.

Sort of how an engine that has 3k miles on it runs more efficiently (and therefore has the ability to make more power) than an engine with 203k on it.

</TD></TR></TABLE>

but if the motor with 203,000 will make more power as long as its rings are still sealing good because the extra compression

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by KoalaEatingTree &raquo;</TD></TR><TR><TD CLASS="quote">It's more for a "fresh start" on the sleeves as opposed to the gain in power.

Sort of how an engine that has 3k miles on it runs more efficiently (and therefore has the ability to make more power) than an engine with 203k on it.</TD></TR></TABLE>

a used motor's sleeves usually wear at the top slightly, so a shop would probobly recomend a bore anyways, I had 66,xxx on my motor and they rocomended it. When a machinist measures the bore they measure it at the bottom, halfway and the top. I'd also recomend finding a compression calculator on google or something, that's what I did and with all the specs of your motor(bore, are of the combustion chamber, pistons etc.) you can calculate the final compression and pretty much design the motor to the specs you want, and see how the bore will affect compression...

 

http://www.zealautowerks.com

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MR.johnson &raquo;</TD></TR><TR><TD CLASS="quote">http://www.zealautowerks.com
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awsome, exactly what I was talking about


Modified by berb_15 at 3:44 PM 5/23/2007