b20 block question

[ewoo]

ok i have a few issues i'd like to clarify for those with more experience out there.

i'm in the process of doing a b20/vtec, but theres been some questions i've had about the build. first, how come i've read/heard that sleeving a b20 block is different than sleeving a b18 block? in addition, while researching b20v's, i read a lot about despite sleeving b20 blocks, they are still more prone to sinking than a sleeved 1.8l block. iono... i think its in the sleeve design. any input?

and due to this sleeve problem, should i really worry about the rod/stroke ratio and cylinder wall pressures? i'd like to be able to rev to 8k, due to the headwork done. it will have a very high-end heavy powerband. but if these sleeving horror stories are true, or if stock sleeves really are shitty, then i'm leaning toward a bored ls block, just for r/s ratio peace of mind and sleeving issues.

fyi, looking to get the m1 abrams sleeves done by blueprint racing.


any and all input would be GREATLY appreciated! thanks!

 

[Aussie]

Sleeving really isn't different. Well the ls blocks have two piece sleeves which maybe makes them a little easier to get out.

I've never heard anything about the sleeves sinking. I would think this has more to do with the sleeves and installer, not the block.

Stock sleeves are ok for an n/a app. The rod/stroke ratio is the same and has nothing to do with sleeving. Unless you stroke it. If you sleeve it and they do a good job.(Golden Eagle is perfect) they won't have any problem and you can rev to whatever rpms you want. Really rpms don't matter, just cylinder pressure and the more rpm the more cylinder pressure but you have to take into account other things like compression, chamber sizing, etc.

I have only used golden eagle sleeves. I've used them 3 times, they have never failed. I've even ran a set way past it's tolerance, still no problems.

 

[ivanvtec]

B20 sleeves are the same exact thing as B18/LS sleeves except that B20 sleeves were bored out more by the factory to gain the extra 0.2 displacement, leaving you with a bigger motor but thinner sleeves. Im gonna tell you what you need to hear... buy aftermarket sleeves!!! i know its pricey and quite a bit of work but if you have your head built you might as well do it right.. unless you wanna be busting sleeves a few months later down the road, just be safe and buy aftermarket sleeves that will guarantee your build will not break down (if you build it right)

after all the a motor is like a chain.. only as strong as its weakest link!

 

[Aussie]

B20 sleeves are the same exact thing as B18/LS sleeves except that B20 sleeves were bored out more by the factory to gain the extra 0.2 displacement, leaving you with a bigger motor but thinner sleeves.
after all the a motor is like a chain.. only as strong as its weakest link!

No your wrong. The sleeves are not the same in the two motors, not at all. The b18 has two-piece sleeves, they are the same thickness, I believe, as the b20 sleeves. The b20 sleeves are completely different, they are 1 piece sleeves, not just bored out ls sleeves.

It is harder to sleeve the b20, because of the middle sleeves being forged together and I guess if it's not done right, the b20 does have a chance of the middle sleeves sinking.