b18bturbo

also depends on what crank u use 89mm vs 87mm or what not 91mm even can be put in there

sweet

iTrader: (5)

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

yes Boostfed, i meant you and Viren as well. and whoever else tries this too.

b18bturbo

hmm intersting thats why it pushes so much torque and gets out of the hole so damn quick thanks josh,..

earl

Benson says not to run more than 25lbs of boost above 84mm or you will start to eggshape the sleeve.

r4adkshn1

just wondering, you enlarge the combustion chamber of the head to match the over sized bore of the block?

boosted hybrid

You dont have to. Its called spot facing the head to the combustion chamber. One school of thought represents the idea that the smaller bore will focus the swirl mixture closer into the center of the piston, giving a greater overall burn. The other school of thought states that the edge of the smaller bore will create a hot spot in the combustion chamber. I left my head 81mm with a 84.5mm bore on the block. I prescribe to the first theory btw.

accordfreak

so going 4mm over would be safe for all honda blocks right? B, D, H, and F series??

boosted hybrid- so NO denotation whatsoever on your block because of the stock size combustion chambeR right??

Quick 200k Mile Motor

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boosted hybrid &raquo;</TD></TR><TR><TD CLASS="quote">You dont have to. Its called spot facing the head to the combustion chamber. One school of thought represents the idea that the smaller bore will focus the swirl mixture closer into the center of the piston, giving a greater overall burn. The other school of thought states that the edge of the smaller bore will create a hot spot in the combustion chamber. I left my head 81mm with a 84.5mm bore on the block. I prescribe to the first theory btw.</TD></TR></TABLE>
I dont know much on headgaskets but.. is your headgasket for the 81mm or the 84.5mm bore?

boosted hybrid

GE 84.5mm overbored OEM headgasket. I would never attempt at using a stock bore headgasket. That is asking for trouble.

No detonation. There are plenty of people on this board that are doing the same thing without any issues.

sweet

iTrader: (5)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boosted hybrid &raquo;</TD></TR><TR><TD CLASS="quote">No detonation. There are plenty of people on this board that are doing the same thing without any issues.</TD></TR></TABLE>

hey Jeff, did you even get your new block/setup running yet?

Suprdave

As far as B20s...84mm Gasket is fine in a 84.5mm Motor.

Suprdave

Quick 200k Mile Motor

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boosted hybrid &raquo;</TD></TR><TR><TD CLASS="quote">
No detonation. There are plenty of people on this board that are doing the same thing without any issues.</TD></TR></TABLE>
not even a hint of pre-ignition after running it hard? When you tuned, did you end up running more retarded timing than standard -0.5deg per lb of boost?

sweet

iTrader: (5)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Quick 200k Mile Motor &raquo;</TD></TR><TR><TD CLASS="quote">
not even a hint of pre-ignition after running it hard? When you tuned, did you end up running more retarded timing than standard -0.5deg per lb of boost?
</TD></TR></TABLE>

i don't think he has it running yet, let alone tuned. i think the motor is in but not yet running or on the road.

boosted92

Has anyone here tried running an 85MM bore on a B16? Is it really worth it to go with a B16 because of the good rod/stroke ratio, or is that just something that's minor?

Quick 200k Mile Motor

I would go with 85mm on a b16. The extra displacement will keep it lively below 4k rpm. It's just the sealing space in between cylinders is not enough imo (any b-series with 85mm bore). I would of course sleeve it, instead of keeping stock cylinder material that thin.

I actually like the bore greater than stroke concept. Have you noticed the new generation of motors have equal or greater bore than stroke, along with great rod/stroke?
Nissan is moving in that direction with the 350Z (99.5mm bore & 81.4mm) which took me by surprise. That is more bore than stroke than the RB26DETT (skyline motor)!

B16 w/ 85mm: 85mm/77.4mm stroke
RB26DETT: 86mm/73.7mm stroke
VQ35DE: 99.5mm/81.4mm stroke

In terms of power production we cant really compare our inline4 to an inline6 or V6 with near equal geometry. They just make their power in less span of rpm (for a heavier car).