wrayzor

I searched for this for a couple hours now and cant find any straight answers. Im exploring my options with what to do with a bottom end for my ls/vtec turbo. If I bore stock sleeves to 81.5mm how safe or unsafe will that make the sleeves? I dont plan on running anymore then 20 lbs at the most dont really wanna push the 400 hp mark thanks

b18sihatch

this is my general opinion on sleeves. factory sleeves arent that thick to begin with. b20 sleeves are even thinner however thats another matter.

however thinning out sleeves with larger bore 81.5mm isnt extremely large, however the ammount of displacement gain you get with it is so minimual that it really isnt even worth it. if you were going from a 1.6l to a 2.0L 81mm to 84mm that would be worth it, however even then you cannot bore a stock block to that large of bore.

IMO with boosted applications and thin sleeves the last thing you want to do is start thinning them out. 81.5mm isnt not safe however its just my own opinion that i wouldnt feel safe with it

Garage 808 Hatch

81.5mm is fine. i made 460 hp on a stock sleeve b16 at that bore. it'll take it, just dont rev th episs outta it

quik sol

400whp on stock sleeves is very easy and been done 100's of times. I wouldnt take it over 400whp though. Sleeves after that mark tend to not like it...but there have been 600+whp stock sleeve vehicles before.

b18sihatch

yea i also agree its not impossible to do, but reving and anything over 400 i would be iffy about. but stock sleeves can normally take a good beating

blinx9900

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by quik sol &raquo;</TD></TR><TR><TD CLASS="quote">400whp on stock sleeves is very easy and been done 100's of times. I wouldnt take it over 400whp though. Sleeves after that mark tend to not like it...but there have been 600+whp stock sleeve vehicles before.</TD></TR></TABLE>

with or without a block gaurd?

b18sihatch

block guards are really not needed for stock sleeved applications, i myself dont feel it does anything to help the block

some people say they do, some people say they dont a matter of opinion really

quik sol

without block guards....

dafuzzbudd

im just getting into this
common sense tells me sleeve guards protect the sleeves when you bore them

does this problem have to do with b18 block having a bad rod/stroke ratio?
the b16 has a perfect one if im correct and would be better vs b18b

dafuzzbudd

is this correct?

b18sihatch

no actually the sleeve gaurds dont protect the sleeves some say they do some say they dont

however sleeve guard isnt a replacement for sleeves so putting a block guard in the block isnt going to make the structural integrity of the block any better as far as psi is concerned. a oem blocks sleeves will only be albe to hold a certain ammount of boost before they crack

aftermarket pistons and rods will help make more power and help take more power. but sleeving a block is the only way to make a block totally bulletproof (depending on the power goal)

to give you am example, my block is a b16 1.6l sleeved,je pistons 8:1, crower h beam rods, the block is totally solid as far as being built is concerned, it could take any ammount of psi/power you would want to make. given the turbo kit is upgraded enough to make the power.

sleeves,pistons,rods are a must if you are looking for a solid block that can take a wide range of power

Topdawgg

id prefer an 81.5mm fresh bore over a 81mm stock that might be out of round....

i ran 81.5mm all year, made 320whp on a mild tune... and beat the **** out of it everyday... it saw 8400 daily

0xenocron

I agree completely.

A 400 hp properly tuned .020 overbored sleeve will handle that power all day, as long as it doesnt see a lick of detonation mind you

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Topdawgg &raquo;</TD></TR><TR><TD CLASS="quote">id prefer an 81.5mm fresh bore over a 81mm stock that might be out of round....

i ran 81.5mm all year, made 320whp on a mild tune... and beat the **** out of it everyday... it saw 8400 daily</TD></TR></TABLE>

Boner_Ben

I made 567whp with my 81.5mm B16 on 29psi. I did just crack a sleeve however but this motor saw tons of passes at the 424whp/20psi/pump gas level.

b18sihatch

those are real nice numbers for stock block

blackeg

i agree with topdogg and xenocron. there's nothing wrong with 81.5mm, but make sure the tune is good.

last winter i blew a thumb sized chunk out of my 81.5mm sleeve at around 8000 rpms, but it was a cold winter night, i had boost spike and i didnt have a fuel system for that much boost so it ran a little lean. if everything stays within the bounds of the setup, you'll be fine with 81.5

beaver

My stock sleeve b16 has been in my car for 19 months now and has 30k miles on it, i run 375-400whp on the street and 440whp at the track. My motor is simple, je pistons, eagle rods, ge blockgaurd, sk2 valvetrain, revving to 9300rpm.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Boner_Ben &raquo;</TD></TR><TR><TD CLASS="quote">I made 567whp with my 81.5mm B16 on 29psi. I did just crack a sleeve however but this motor saw tons of passes at the 424whp/20psi/pump gas level.</TD></TR></TABLE>

Damn man that sucks, when did that happen?

whiteef8

i heard last night up at tsr. Man i loved that car, something about doing it so big with a teenie motor and stock sleeves (no offense on the teenie part, haha) 2 BIG for Boner

Boner_Ben

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beaver &raquo;</TD></TR><TR><TD CLASS="quote">

Damn man that sucks, when did that happen?</TD></TR></TABLE>
It happened at Imports vs Domestics this weekend. Car went 10.4@140 on 23psi, then on 30 psi on the next pass it went 10.4 @ 142 and was idling like a subaru (cracked the inner iron portion of the sleeve). Then on the next pass it went all the way through to the coolant jacket and ended my weekend. Time for a bigger badder setup for next year.

b18sihatch

for going out with a bang or boom lol

civicjdmb16a

81.5

DraginX

Mine was bored to 81.5mm also, pushed out 400+whp all summer long driven hard as a daily driver, seeing 450+whp at the track. I would say if you are spending the money to go with new pistons/rods but don't have the extra cash to have the bottom end sleeved, do yourself the favour and atleast do the .5 overbore to ensure you have some true cylinder walls.

Topdawgg

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DraginX &raquo;</TD></TR><TR><TD CLASS="quote">Mine was bored to 81.5mm also, pushed out 400+whp all summer long driven hard as a daily driver, seeing 450+whp at the track. I would say if you are spending the money to go with new pistons/rods but don't have the extra cash to have the bottom end sleeved, do yourself the favour and atleast do the .5 overbore to ensure you have some true cylinder walls.</TD></TR></TABLE>

exactly...

hopefull this thread will show you that there is nothin to worry about now man...

b18sihatch

do you feel it is exacly worth the small displacement gain?

i had a sohc fulley built with .020over pistons and since it was NA i couldnt really tell if it actually made any kinda power difference, the motor was fast prolly 160+hp howver i dont know that that small of a displacement gain would actually benifit in power.

maybe just ot make sure the sleeves are round&gt;?

Topdawgg

i didnt bore mine out for the gain... thats for damn sure...

i did it to make sure the cylinders were true