AzN_Flava

Okay.. I'm confused on the b18 and the b20 now... maybe its because im up at 6:00a.m. and can't sleep...
ANYWAYS...

b20 =84.5 mm b18 = 81 mm yes??

okay now.. say if we were to take both motors and bore it out and build it up to the same way... both are sleeved, bored, piston changed, strengthened, etc etc....

Which would yield more power with vtec and turbo???

or are they just the same except in factory stock mode?

reason im asking is.. i wanna go vtec turbo... I dunno if it is worthy my time to go get a b20 and then build that up.. or stick with my b18 and build that up... (ignore the cost of getting the b20 because i think i can sell my 58125miles 94 b18b around.. and have the b20 cost not too much)
i want 11/12's *yes im dreaming* so i wanna see if i need the b20 to do that.

thanx... and i will now try to sleep.

DIRep972

iTrader: (1)

im not exactly sure what you are asking but the B20 will make more power simply cause it has more displacement.

If i were you, i would just turbo the LS motor and while running that maybe you can build a B20vtec to drop in.

AzN_Flava

ummm okay.. i just want to know..

if we took the b20 and b18 and bored it out adn sleeved it out and did the pistons up and shiet the same way... wihch would be a better engine for vtec adn turbo?

i mean.. we both bore it both out to 2.2 or 2.3(both motors) which would be better?

93LSivic

Think about it man. When you bore something, what actually happens? The cylinder walls get thinner, right? Now, can this be good-to an extent, sure. But overall it is actually weakening the cylinder walls. Even with sleeving it wont be as strong as a stock bore B20 that has been sleeved.
Also who's to say you couldnt take a B20 and bore that to a--Oh lets say B22??
Any thoughts people???????????

Ray

I dunno what you guys are talking about.

The difference in the B18a/b and B20 are all in the cylinder walls, stock B18a/b bore=81mm and a stock B20b/z Bore=84mm. B20 cylinders walls are thicker to make up for the larger bore, plus they are siamese sleeves(not inidividual sleeves like b18a/b/c)

You cant bore out a stock b18/a/b block to 84mm but you can resleeve it, then bore it out larger.
And if you resleeve a B18a/b block and bore it out to 84mm it will have the same as a B20 block but with stronger sleeves. And you can only bore a sleeved block out to a certain point since the engine is only so big.



[Modified by Ray, 8:57 AM 12/10/2001]

InfamousRS

I understood him perfectley. Probably because this is what I want to do to my engine. The only difference in the the b20 block from the b18b block it the bore. they have the same crank with the same stroke. He is asking if he resleaves his block and has it bored out to 84.5 mm, would it make the same power as the b20 block would, and as far as I can tell, the answer is yes. I plan on going with Golden Eagle Godzilla sleaves with the absolutley largest bore I can get. Does anyone know what that is?

While we are on the topic of bore and stroke, cas someone clear somthing up for me? How do you figure out displacemet? I figured it was just figuring out the volume of a cylinder which would be the bore x stroke? Every time I have calculated it, it has come out less than what I know the dissplacement is.

AzN_Flava

YEAH THANK YOU!!! hehe someone is in the same boat as I am. I hear wonderful things about the b20 like it being so torquey(spelling??). And i thought that since it is more torquey then the b18b... it would be better then the b18b..(well not really sure im assuming)

but... say we bored the b20 even more? to i dunno 86mm (is there such a thing) can we bore the b18b out to that much too? and yah... would they both be just as strong internally? becuase someone posted it that i would be thinning out the walls...

i should really post in the daytime.. i make no snese

Ray

Bore^ x Stroke x Pi / 100 = displacement

Math is Fun(when it relates to cars)

Ray

I hope you didnt ignore what I posted flava, I think i answered most of ur question above.

As for how much you can bore out a Sleeved LS, I have heard of people with 86mm bore but they were running all motor. With 86mm bore you might have head sealing problems.

SCREWD

Does anyone know if someone has ever upped the displacement of a B20 to maybe 2.2???
Ray, since math is fun. Would you be able to use the stock B20 rods with custom pistons if the bore were 86 or 87 mmm??

TIA

ekb18c

The only difference b/t b20 and b18 is the displacement.

b20 = 84.5 mm
b18= 81.5 mm

if you take a b18 and resleeve it, then bore it out to 84.5mm then its the same thing as the b20 block.

bodykit=rice

ummm

B20 = 84mm

All other B-Series = 81mm

InfamousRS

If I were to resleeve my block with Golden Eagle Godzilla sleeves, what is the biggest bore I could have?

ekb18c

if you get it resleeved you can ask for any bore you want!! 84.5 is the most i would go though.

InfamousRS

Why not 85? Endyn makes the piston for the same price as the 84.5.

Ray

Math is much more interesting when it involves cars like calculating CR and such And with a bigger bore you still use the same rods. Some of you seem to ak the same questions here, so im done with this post.

With 86mm bore the block displacement would be 2068cc like I said you'll prolly have head sealing issues and I wouldnt boost with that.

Tomakit

(copy)Why not 85? Endyn makes the piston for the same price as the 84.5.
(copy)

Have you ever looked at cyl sleeves? There must be 10,000 pics of various motors with the head off so you can see the sleeves on this board. Take a look at some, and then rethink why it might not be such a good idea to "just go to 85mm cause endyn makes a piston that large"

Tom

01geeser

ur not gonna have very much sleeve area better cylinders even if you sleeve it.

boosted3g

I talked to Vince at Golden Eagle and he told me what some quick 8 guys are running and 85mm and a ton of boost is not unreasonable. He has a very good bit of confidence in his product and I trust him.

AzN_Flava

Ah okay Ray.. i think the more im reading this post over the more i understand. thank you...

You guys have just helped me decide what i wanna do... From this.. i looks like i will just keep my b18b and bore/resleeve new pistons etc... so it'll just exactly be like the b20b but even better...

You have now saved me 600 bux.. thank you so much

Y don't ppl buy a b18b and bore it resleeve it out to do ls/vtec... why do they insist on doing crv/vtec???

Tomakit

(copy)Y don't ppl buy a b18b and bore it resleeve it out to do ls/vtec... why do they insist on doing crv/vtec???(copy)

1) if you aren't boosting lots of psi, no need to resleeve.
2) if you don't re-sleeve there is no downtime while the block gets shipped out to have the work done to it.
3) not everyone has the $$ to re-sleeve, and b20's can be had for pretty cheap

Tom

AzN_Flava

Ah i c... Got it... Resleeve for boosting lots of psi... costs more...


THANK YOU TO EVERYONE WHO HAS POSTED... I am no longer confused!

but watch me post in a couple of days on something else hehe... i have lots to learn still...

thanx everybody

Ray

stock b20 block seem o be pretty hard to find, I have no idea how much they go for. Almost every honda builder wants it. My local machine shop is working on 5-6 B20s and a B21a.