95BlkGSR

i wanted to know the opinion of every1...

i am debating on 81mm or 81.5mm

how much of a difference is there?

or should i jus get some 84mm and be done with it

goals or 300 hp plus+++


id rather go with 81mm or 81.5 i just want to know wat everyone thinks

going with some JE's or Wiseco w/ Eagle Rods - 9.1 compression

Timmay

well you cant just throw 84 mm pistons in a 81 mm block, you will have to sleeve
ive seen stock gsr blocks make over 300 whp
you can get away with 81mm, but going a bit over never hurts

Muckman

iTrader: (2)

Dont go too much bigger unless your resleeving it.

turboEGhatch

You know you have to sleeve it to run more than 81.5 or 82mm, eh.

OMFG, I hate those new ads! I see them below the first post and think nobody has replied, then I make an idiotic post saying the same thing everyone else said!

95BlkGSR

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Muckman &raquo;</TD></TR><TR><TD CLASS="quote">Dont go too much bigger unless your resleeving it.</TD></TR></TABLE>

yes i no...im just wondering really if i should go 81.5 or 81mm cause odds are i wont be resleeving...and i wondered how much of a difference it really makes

and another question...has any1 had there block bored out...well stock sleeves...about how much is it...like 500? 100? 1000? 50? i have no clue....jus was wondering a ball park number

Evanmb44

if you are not going to resleeve it, i would stick with the stock bore......but you could sleeve it for insurance while you are at it.....boost is addicting and you may want more power later on. if you were to sleeve it now, you would not have the hassle later on down the road

95BlkGSR

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Evanmb44 &raquo;</TD></TR><TR><TD CLASS="quote">if you are not going to resleeve it, i would stick with the stock bore......but you could sleeve it for insurance while you are at it.....boost is addicting and you may want more power later on. if you were to sleeve it now, you would not have the hassle later on down the road</TD></TR></TABLE>

yea...ive seen stock sleeve run as high as 500hp...

but i understand...it would save the hassle later on

turboEGhatch

Bore it to 81.5 at the least, you want to get fresh cylinder walls, a clean hone, and the clearances you want. If you stick stock bore you might not be able to get your desired piston-to-wall clearance, and you could have a motor that's noisy on cold start.

95BlkGSR

ahh ok this is wat im looking for ^^^


and power gains? that dramadic?

adictionbass

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turboEGhatch &raquo;</TD></TR><TR><TD CLASS="quote">OMFG, I hate those new ads! I see them below the first post and think nobody has replied, then I make an idiotic post saying the same thing everyone else said!</TD></TR></TABLE>

same here...

95BlkGSR

bump........any1 else?

Dunc

stock size would be fine....I have 8.8:1 81.5mm pistons in my setup (not sleeved) and I'm making 351whp right now at 13psi

I chose 81.5mm instead of the stock 81mm because the motor had some miles on it so I figured that the bore of .5mm would clean up the cylinder walls nicely for the new pistons.

95BlkGSR

i think ima do that...seems to be the best...

how much did it cost u?

Dunc

rods/pistons were 790....to pull the motor, bore .5mm, re-deck the block, and reinstall motor was 750.

cnydc2

If the cylinder walls are not messed up I would run a hone down them and try to stick with the stock size pistons. That way you have a little more room to bore if anything happens and you need to clean up the cylinder walls instead of resleeving the block.

BTW run a 9.0:1 comp piston and you should be easily to hi over 300whp without any reliability problems.

riceball777

rs machine charges
$88 for bore and hone
$80 to deck block
$35 for hot tank
$35 micro polish crank
$160 balance rotation assembly

and yes you should over bore a little so you know the cylinders are perfectly round and you get your desiered piston to wall clearance

95BlkGSR

ok thanks man that gives me some idea...ive never had this done so...do i need to get all that done? or jus bore and hone?

95BlkGSR

?