So I have a messed up b18c motor, and the cylinders are egged. I found a guy with a b18a1 motor and I used a compression calculator and it said that my compression would only go up by .5 points from like 9.0:1 to 9.5:1, because of the deck height difference.

Is this true? Has anybody used a b18a or b18b block for a rebuild on their b18c setups? Is there any reason why this would be very ill advised?

Thanks guys.

 

the only b-series block that has a different, shorter, deck height is the b16/b17
b18's are the same

 

no more oil squirters..

 

That's not what the compression calculater I found online says. HMMM

So the b18a doesn't have the oil squirters but the gsr block does. But if you're running forged pistons then people say you don't need the oil squirters right?

 

Either the deck height has to change to compensate for the different strokes of the b18 cranks, or the rods have to be different lengths, and I thought all b series rods were the same length, just deck heights and crank strokes changed.

 

bee series rods are defenetely not the same lenght

B16a: 134mm
B17a: 131.87mm
B18a/b B20b/z: 137mm
B18c: 137.9mm
B20a: 142.75mm
B21a: 141.7mm

 

it will work. b18 a/b block is shorter. but the but the stroke of the gsr is less than the ls...it will fit.


try this one out
http://www.zealautowerks.com/

 

the blocks are the same height; what differs, hence change in compression is pistons and stroke.
P72 block also has the same stock piston to deck height than the pr4

 

thats not what all the compression calculators say...i thought they were the same deck height, but i have been informed there is a slight difference.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rhd type r &raquo;</TD></TR><TR><TD CLASS="quote">thats not what all the compression calculators say...i thought they were the same deck height, but i have been informed there is a slight difference.</TD></TR></TABLE>

what calculators are you talking about?
the only blocks that have a shorter deck height are the pr3 blocks( b16/b17) rest are the same.
I think your getting things confused

ohh i see what your talking about.. compression calculator is wrong. period.

 

I highly doubt the calculator is wrong.
http://www.zealautowerks.com/

Go click on different blocks and you will find a slight discrepency in the deck heights, which will for sure change your overall compression. Also notice that the b18c and the b18a have different rod lengths. Why? Because the rod length and deck height need to be different if the cranks are different, which they are cuz they're not the same CC from the factory.

 

All B18 blocks have the same deck height, what differs is the rod length and stroke length. GSR's and Type R's have slightly short stroke and therefore slightly longer rods, hence the displacement difference of 1797 vs 1834.

Long story short, just make sure your rods match your crank, and you choose the correct pistons for your application so you know what compression ratio you will have.


BTW, that Zeal site talks about Effective Compression Ratio being static C/R X pressure ratio in atmospheres from boost. That right there is enough to discredit that website. Effective Compression is a bunch of horseshit. How else does a 2.0bseries that makes 160whp NA, make 450+ whp on 15psi from a T67? According to that calculator, it should make 320whp.


Modified by Drag_S14 at 3:56 PM 10/9/2006

 

LOL, read any tuning magazine and they will tell you that effective compression is just what you described.

It isn't horseshit, its for real, ask erl.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beef-cake &raquo;</TD></TR><TR><TD CLASS="quote">LOL, read any tuning magazine and they will tell you that effective compression is just what you described.

It isn't horseshit, its for real, ask erl.</TD></TR></TABLE>

you obviously have no clue about rod lenghts nd block heights. once you get personal experience you can speak.
if you calculate stroke and rod lenght along with piston to deck height you will see that te blocks are the same height.
no guessing here..facts

get youe facts right noobie

 

Dumbass, you also need to know the blocks deck height to calculate the compression. You can only have one missing variable, not two for this application.

I don't need your dumb ******* remarks on my thread, I want somebody to give me definitive proof somewhere that all b18's have the same deck height.

Such as a reference to a honda manual or something like that. I'm not going to take the word of some jackass that's flaming me for asking questions.

http://www.tamparacing.com/for....html

Guess that thread is also wrong about the b18 deck heights.

B16= 203.39mm
B17a= 208.28mm
B18a/b & B20b/z= 211.84mm
B18c= 212.39mm

I can't believe that somebody would just make up 4 different deck heights and pick those numbers out of the sky. Muller, you're an idiot. Don't speak unless you know what you're talking about.


Modified by beef-cake at 9:41 AM 10/10/2006

 

the setup works I currently run gsr internals in my ls block. end of discussion. they have the same deck height.

 

Dude, "works" and "they are different" are two different things. If you calculate the compression numbers, the b18a/b block would have a .5 higher compression, thatn with the b18c block.

This .5 does matter to some people if they're running high compression setups, SO STOP SPREADING MISINFORMATION!!!

 

ok so i guess i just have to show your ignorance and cockiness with numbers.
Another thing, everything i give my opinion on is based on real actual hands on experience; against well you with Internet mechanic/builder experience. So please don't curse people that are trying to help you ....

Now with the rod lenghts posted above...

*b18c block: 87.20 mm stroke with a 137.9mm rod.

Now, you add half the stroke + rod lenght

43.6 + 137.9 = 181.5

*B18A+ : 89mm stroke with 137mm rod.

44.5 + 137 = what do you know.... 181.5


Now onto the shorter blocks..

*B16 block: 77mm stroke 134mm rod.

38.5 + 134 = 172.5

*B17 block: 81.4mm with 131.8mm rod.

40.7 + 131.8 = 172.5

there you have it.
Now, i was a little '' wrong'' by the the compression heights

PR3 pistons have a compression height of 29.972mm
P72 pistons have a compression height of 30.0482 mm
PR4 pistons have the same compression height as P72's
P73's and PCT's have a longer compression height(meaning more compression than the rest, with PCT's being the highest at 30.734mm
If you put PCT pistons on your b18 block they will sit flush with the deck, do the deck height math.

yeah i guess the link you posted is also wrong.. what can i say..
And no if you put gsr internals on a b18a block it WILL have the same compression as their gsr couterpart considering your using the same head

SO STOP SPREADING MISINFORMATION!!!

 

You don't know what you're doing do you?

Use this formula:
Deck Height - Compression Height - Rod Length - (Stroke/2) = Piston Deck Clearance

Now you're telling me that the deck heights are the same?

YOU JUST PROVED YOURSELF WRONG. Because you're suppose to add the compression height to your rod length plus half the stroke to get the deck height - piston deck clearance.

If the half stro0ke plus rod length figures you used are correct and are both 181.5, but the LS AND GSR have different compression heights on the pistons then the DECK HEIGHT HAS TO BE DIFFERENT.

Lets use your figures of 181.5 now add the ls compression height (30), you get 211.5, and for the gsr (30.05) you get 212.

They're different aren't they? Now look at zealautowerks and you will find the gsr is off by .39 and the LS is off by .84, and why is that? Because that's the piston deck clearance figures for those motors.

Where did you get your stroke rod length figures from anyways? Off the net? Are you sure they're right? Maybe they're wrong like zealautowerks, which is why I want to know if somebody has a honda manual that shows the deck height numbers.

Don't flame me on my thread because i'm asking a legitimate question, calling me a noob, you're being a jackass. I asked if anybody has a honda manual that shows this, not your internet produced figures based off figures that you say might be incorrect.

 

I asked myself the same Q, but I think the zeal calculator is wrong, just try to calculate stock Cr on ls and gsr engines and compare them to oem honda specs

 

deck height is the block alone. b18 families are the same.
PR4 and P72 have a minor compression height difference, the difference is that they ''sit'' a litte lower from the top of the bore.
The only piston combo that will yield 0.0 compression height is the PCT ; the rest sit a little under.


<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beef-cake &raquo;</TD></TR><TR><TD CLASS="quote">You don't know what you're doing do you?
Lets use your figures of 181.5 now add the ls compression height (30), you get 211.5, and for the gsr (30.05) you get 212.
</TD></TR></TABLE>

mmm yeah.. 181.5 + 30 = 211.5 181.5 + 30.05 = 211.55 not 212....

 

you are only saying that they are the same because that's what you've heard. You have no real world proof on this. I'll PM erl and ask him to post on here about it, cuz I think you're pulling your "they're the same idea" out of the sky.

Jetpilot, you are right that I could calculate the compression ratios but where do I find the actual stock compression ratio numbers and know they're right or not?

DOES ANYBODY HAVE A SPEC SHEET FROM A HONDA MANUAL?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beef-cake &raquo;</TD></TR><TR><TD CLASS="quote">you are only saying that they are the same because that's what you've heard. You have no real world proof on this. I'll PM erl and ask him to post on here about it, cuz I think you're pulling your "they're the same idea" out of the sky.

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

you could not be more wrong, i say they are the same because i have had 2 blocks side by side.
If you need picture proof paypal me some money i will gladly do it.
What tha hell are you talking about ''the same idea''?

You keep being offensive even though your wrong.
have you even seen a B-series apart?

Ask Earl and tell him that your idea is that pretty much all B-series blocks are different heights, you'll see what he tells you..

On the side; wich spec sheet do you want?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beef-cake &raquo;</TD></TR><TR><TD CLASS="quote">
DOES ANYBODY HAVE A SPEC SHEET FROM A HONDA MANUAL?</TD></TR></TABLE>

NO, i searched and couldnt find anything in the 45 seconds i had, BUT, I can tell you this: B16/B17 have low deck height and B18A/B/C have a taller one. they are all the same, stop fighting online, it makes you look very stupid.

 

LOL, I said that b18a/b are different than b18c, YES, that's what I said.

And yes I've seen b series motors apart. b16 with ctr internals on spray, b20 with ctr internals and big cams. About to take my gsr and LS apart to combine them. And I have a b16 in my hatch.

Dmoto, I really am worried about "fighting online" and i'm horrified if somebody thinks i'm dumb. Oh bummer. Muller is the one that started dissing me in the first place.