heheh I like the thread this has become. Good information, I’ve got nothing really to argue about, but we can all agree that this is good information!
agreed!:read: ill be the gunea pig for our on stock sleeve boosted b20z.
Originally posted by teg92
heheh I like the thread this has become. Good information, I’ve got nothing really to argue about, but we can all agree that this is good information!
I agree…this is good info for everybody here to know about. I’m pretty sure this topic might come up again in the future, so…
ARCHIVETHIS
If you were to create anything over 300 crank Hp you are at the weak point of the block. Yes the honda blocks are open at the top but this is for a reason. The head gets cooled of easily but the cylinder walls have to disipate the heat of the pistons thru the rings. The oil helps cool the pistons form the bottom. The top of the cylinders is where the most heat is created since it has the highest pressure. This area if it was sandwiched between the block and the head it can build a hot spot which can lead to unwanted detonation.
The cylinders sleeves from the factory are made of a weak material. This is the reason why the stock sleeves on the B20 block you’ven posted have cracked. Some people have had luck from usage of block guards. But the cylinders do still float even with a block guard. It really is the vibration that kills them.
There are two companies that I’ve come across that have resleeved blocks and have done it the best I’ve seen. The first I would recommend would be golden eagle manufacturing. Their sleeves are installed so the sleeves pressure is on the top of the block. This is done by removing the entire sleeve with the aluminum jacket. Then the outer edge of the coolant jacket is bored out, not the entire lenght of the sleeve but only the top few mm to accomodate a t-shaped sleeve. The top of the sleeves are also have the gaurd sunk down so as to accomotade a better flow and elliminate the heat spot situation that I’ve described above. The isn’t crutial to brace heare since you never alow the flame to hit the piston until after piston dwell. The company also pressure tests each block well beyond the level your car could ever achieve.
The other I would recommend would be darton. They have thier sleeves machined in a very similar way but the guard does come all the way to the top. Although this can create heat spots there really hasn’t been too much of a problem noticed by users.
Both blocks use the outer edge to hold the sleeves and thus prevent the sleeves from moving vertically and horizontally. Which is much better than a insert.
First of I would use an 84 mm sleeve. If you are to have this insert installed on a b18A/B block you will need to use a B20 head gasket. If you were to have it done on a B16/17 or B18C you will need a head gasket from Cometic. I prefer to use a tri-metal head gasket like the factory rather than a never seal copper head gasket.
The vtec blocks are braced better from outside but several guys have had great dependability on a B18A/B pushing well over 200hp/liter.
A larger sleeve will make it easier to allow the air to enter and exit the cylinders. which will make more power. Look at it this way take a B18a/b it has a bore and stroke of 81 X 89 mm. To increase displacement you will need to alter this. Say you choose the stroke. You will to stick a older (dinosaur) crank to make it a 81 X 95 mm a 6 mm stroke increase to make it 2.0 liter. This combo has made your engine rod ratio go to crap and the bore to stroke ratio now more undersquare. It also made your you engine now rev like a piece of crap d-series civic.
Now look at the bore. to get the same displacement you will need a 84 mm bore which is a 3mm bore increase. This will allow the same rod ratio and bring the bore and stroke ratio toward square and rev better.
The route your are taking with the 84mm sleeves is better but yo9u would be better spending your money having the block resleeved than using a crv block.
I dont know if this has been posted or not cuz I missed reading a buncha posts but the cc difference between B16A and B18A/B are different then the difference between B18A/B and B20B/Z. B16 and B18s have the same bore but different strokes. The B18 and B20s have different bores but same stroke… as we all know. But the thing is (as far as I know) torque is created better thru a longer stroke as opposed to a wider bore. I dont want to start a debate or anything but skinnier cylender walls for a bigger bore is probably decreasing durability of the motor. I almost think it was just an easy shortcut for Honda creating the B20.
Maybe what I just said makes no sence at all, but Im just throwing out new ideas to think on.