Alright, after more than an hour of searching and turning up exactly jack squat, it's time to just come out and ask. My engine is starting to take a poop on me, so I'm looking into some cheap options, which are as follows:

-B18B block with P30 pistons and stock, mildly ported LS head
-B20B block with either PHK or RS Machines pistons and mildly ported P8R head

Whatever option will use Crower 62403 cams, a Toda header, a Junk2 IM, and a nice exhaust. This will be used for tracking, so it needs to be able to take some abuse. I'm shooting for something like 11.0-12.0:1 CR, with no larger than an 85mm bore on the B20. I couldn't find any dynos or anything for anything close to either setup, so I'm looking for suggestions or previous experience.

 

B20 hands down.....

I run a stock sleeve b20 with the rs pistons. Trust me when I say, i've run every size motor in NA and 2.0 + is the only way to go. Always go with the bigger motor if you can afford it.

 

That's where I'm leaning. I was running the LS previously, and more recently swapped in the B20, and man, what a difference! My ONLY concern is with the cylinder walls. The block has seen some abuse, so I'm guessing 84.5mm is the minimum I can get away with.

 

84.5 mm should be no sweat. what kind of driving does the motor see? Street and drag and they hold up fine, but road racing is tough. If the tune is right and water temperature is kept on check it will last a long time.

 

my stock B20Z did really well at gingerman for the past couple of years.

 

B20b/z hehe gotta rep for our CRV motors... but if you have better plan or more plans i should get what ever is cheaper...because your gonna rebuild it anyway

 

It will be used for roadracing, and I don't go out without a good tune. Water temps have been great with the current setup, and the only thing that'd really change would be the higher CR from those pistons, so it should remain cool. The stockish B20B I've been running has been great, it's just tired from LOTS of abuse. I got it from a friend, who had abused it a bunch before me, then I went ahead and piled on more.

So, if that's decided, PHK or RS Machines (higher CR)?

 

b20z for sure

 

comparing a stock b20 bottom to a high CR b18b with the same head/cams, the b20 will make alot more power earlier but the 2 motors will peak about the same. a high compression b20 vs a b18b with the same CR the b20 will dominate it.

 

Since you want the motor reliable... May I suggest:

-Have the cylinders honed

-Have the rods shot-peened and use 8mm ARP rod bolts

-Use tri-coated bearings: main and rods (ACL if your tolerances allow)

-install your new piston rings using 180 deg method instead of the 90 deg method honda recommends.

-use an newer ( from OBD-II B-series) oil pump (unless you use a B20 block b/c it will already have it)


I recommend a B20, but that decision is up to you. For reliablility, I recommend making sure you do a proper rebuild.

 

i was planning itr pistons for my block.. but all that will have to wait.. i just picked up a pr8 head..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hybrid_vtec &raquo;</TD></TR><TR><TD CLASS="quote">Since you want the motor reliable... May I suggest:

-Have the cylinders honed

-Have the rods shot-peened and use 8mm ARP rod bolts

-Use tri-coated bearings: main and rods (ACL if your tolerances allow)

-install your new piston rings using 180 deg method instead of the 90 deg method honda recommends.

-use an newer ( from OBD-II B-series) oil pump (unless you use a B20 block b/c it will already have it)


I recommend a B20, but that decision is up to you. For reliablility, I recommend making sure you do a proper rebuild. </TD></TR></TABLE>

1. Cylinders will be bored out, going to go with 84.5mm
2. Shot-peening I'll consider, but ARP rodbolts for sure.
3. ACL bearings, gotcha.
4. Will do.
5. Already have a new oil pump on there, so no problemo.
Thanks for the suggestions!