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MRJDM
13-07-2004, 05:14 PM
The posting process involves machining and tapping holes in the thrust sides of the block and torquing in threaded aluminum “posts” that physically “connect” the outer part of the cylinder with the outside (peripheral) walls of the block. With these “posts” installed, if the cylinder walls are going to move, they have to move the outside walls of the block too, so they add a tremendous amount of strength, making the block capable of withstanding a lot of abuse. This modification also has no ill effect on cylinder cooling, which is something I’m big on these days.

i got this from http://www.theoldone.com/articles/badtothebone/ . does anyone know the advantages and disadvantages of posting

pornstar
13-07-2004, 05:15 PM
yer, the guy who does it gets money of ya ;)

SP0017
13-07-2004, 05:20 PM
resleeving is gonna cost you a bomb. whether you use a b20 block or b18 block.

I don't know how much posting will cost and i'm not sure if you can both use a block guard and post the cylinder walls too

SP0017
13-07-2004, 05:23 PM
Advantages are as posted in the article.

Theoretically i would think that because the posts and the cylinder walls are made of different materials, they might expand at a different rate when its hot which might create pressure on the walls too. Just a guess

pornstar
13-07-2004, 10:04 PM
yet if u think about it, where does posting differ to block gaurding besides the name and what the seller says?

SP0017
14-07-2004, 10:38 AM
thats why i said i'm not sure if you can do both posting and using a block guard cos they both claim to do the same thing, provide support for the higher part of the cylinder walls cos thats where there is most pressure.

tinkerbell
16-07-2004, 01:21 PM
MRJDM - how much boost will you be running?

this will dictate the amount of engine strenghtening you require.

MRJDM
16-07-2004, 02:47 PM
im going to be building a high comp engine

tinkerbell
16-07-2004, 03:00 PM
in that case i woudl consider sleeves if you are using a B20B block...

i dont know anyoen in Aussie with 'posting' experience...

(not many sleevers for that matter either!)

Weq
16-07-2004, 03:17 PM
DIY posting! www.homemadeturbo.com has a good guide :)
sleeving, id look a buying somethign built int he US from a US forum. its always cheaper buyin something someone else has spent US dollars on.

Breeze
16-07-2004, 03:45 PM
Posting goes way back to the old hotrod days. I have posted early honda motors that require stiffening to make big power with floating sleeves. Posting is much better than block guard as you don't distort any of the engine components when fitting or apply any pressure on any surfaces. You only torque up very loosely. Block guard also creates hot spots which are not caused by posting. This is exaggerated because block guards sit at the top of the bore closest to where the combustion process occurs and where the cylinder needs high level of cooling. People with block guards often find they have to run less advance because of this in a street car to prevent detonation. Drag cars will usually run from cold.

You only need to post on the thrust side of the block and it is cheap to do and even the average mechanic should be able to do it as long as you have some threaded alu rod, correct size drill bit, epoxy and the right thread tap.

My experience with early honda blocks has shown they are reliable with a 2mm overbore and 20psi boost with static comp of 6.8:1. My personal opinion is that sleeve splitting in later blocks is more the result of poor tuning than poor manufacture.

Good luck

pornstar
16-07-2004, 04:05 PM
sounds good breeze except static comp of 6.8 would be meh to drive on the street. agree about sleevse cracking, more often than not tho, that cracking isnt just tune, its also the fact of cylinder pressure, and sleeves walking under boost...

for high NA MRJDM, u need displacement and rpm to get real power, if thats the case might aswell sleeve it man. Adrian makes a mean sleeved block.

Weq, for an engine, stay in australia man, overseas ur going to get into trouble especially with high shipping costs.

SP0017
16-07-2004, 05:16 PM
There is this place in melbourne that does darton sleeves, i think its the only place but i can't remember the name.....

acongdon
18-07-2004, 10:20 AM
I've built two B20 with B16 head motors. One posted and one with a blockguard. The posted motor
soon had oval bores in one and four and had to be rebuilt. We had to resleeve the motor in the end.
We put the problem down to too much pressure on the pins and as soon as the engine reached full
operating temperature the liners squeezed and being one piece all the movement ends up in the end
cylinders. The blockguard motor is still fine. The B20 liners are very weak.

wynode
07-09-2004, 03:11 PM
I thought this might be kinda helpfull too

http://www.muller.net/sonny/crx/engine/posted.html

blackdc2
08-09-2004, 10:46 AM
in that case i woudl consider sleeves if you are using a B20B block...

i dont know anyoen in Aussie with 'posting' experience...

(not many sleevers for that matter either!)

i got my block posted...

MRJDM
08-09-2004, 12:13 PM
blackdc2- what motor did you get posted , 18 or the 20?

blackdc2
08-09-2004, 01:54 PM
blackdc2- what motor did you get posted , 18 or the 20?

18

tinkerbell
13-09-2004, 10:11 AM
is what you had done called posting?

i dont think it is Jase...

tinkerbell
13-09-2004, 10:12 AM
if it is called posting (ie i am wrong) - then it is not the same as the posting that was refered to in the initial post...

blackdc2
13-09-2004, 11:17 AM
what do you think posting is??? i was under the impression was dowels being inserted between the bores and the block

tinkerbell
13-09-2004, 01:27 PM
what do you think posting is??? i was under the impression was dowels being inserted between the bores and the block

posting is horizontal...

http://www.theoldone.com/articles/badtothebone/Cylinder_Finish_1.jpg

'doweling' is vertical...

tinkerbell
13-09-2004, 01:29 PM
but i do stand to be corrected,

as i think there are a few different names for the same things here...

but i understand that this thread is about the method that is seen in the pic above...

blackdc2
13-09-2004, 01:33 PM
I stand corrected, just a miss interpretation of the word posting. I have never seen the above before, it appears to do that same thing but it would also appear to involve more machining/time

tinkerbell
13-09-2004, 01:56 PM
I stand corrected, just a miss interpretation of the word posting. I have never seen the above before, it appears to do that same thing but it would also appear to involve more machining/time

but theoretically would the single horizontal post create a pressure point that might lead to 'ovaling' like acondong has suggested?

i think the horizontal dowels would offer better support for the floating cylinders...

but a blockguard would seem best?

blackdc2
13-09-2004, 02:22 PM
well i have 36 dowels in my block, so i think that would be stronger than a few horizontal posts.

block guard would probably be the best as it is a perfect fit the whole way around the bores, but it would also be the most costly.

tinkerbell
13-09-2004, 02:54 PM
well i have 36 dowels in my block, so i think that would be stronger than a few horizontal posts.

block guard would probably be the best as it is a perfect fit the whole way around the bores, but it would also be the most costly.

i have been meaning to ask you - how does the coolant flow around the dowels? do they go all the way to the bottom?

(i dont have the allmotoraustralia address saved on my home PC - so i cant check out the hard tuned thread to check?!?!)

blackdc2
14-09-2004, 09:49 AM
nah, they are only about 2" long, so the coolant can still flow around the cylinder walls, i had the head off about 5000km after install and there were no signs on the cylinder walls of heat spots or anything like that at all.