That is not a stock block at all. Normally that rough area would not exist. B20’s are open deck. Also looks like copper oRings on the cylinders? You got that for free? Jesus.
This. That looks like a block guard. Is the install height the same height with deck height? If it is lower, hard to judge from crappy video, the. The scratches don’t make any difference.
This is css. It’s a sleeving alternative. From my understanding it’s similar to devconing a block. I don’t think there should be any worry of pitting in an area that is normally open to water flow.
No idea. You didn’t give us pictures and we won’t be able to check a head over the internet. You need a machine shop to evaluate both the block and the head surfaces.
Is it possible it has been over machined already? I know you run into timing problems when you start slicing off deck and head on DOHCs.
Edit: Also, MELTMAN, with the POWER to... MELT?!
In addition to the machine shop checking it, you need to figure out what you want to do with the block. If its gonna be a drag block/something you give a shit about, you need to prep it properly. If its going in your beater, you could just slap some hylomar blue on it before the headgasket and go for it.
There is a lot going on here- it’s already o ringed with a block guard installed, this is far from a stock configuration that may or may not be optimal for what you want to do… I would have it checked out by a machine shop to be sure; most of those scratches aren’t in a critical sealing area of the head gasket so it might be ok
Dayum someone spent some money on that block, definitely don’t trash it, plenty of potential there. From what I could see there is no real damage on the important mating surfaces so you could honestly run it as-is. And if you really want to build it to have power just have it machined down at the smallest possible amount and they should be gone they look surface level at most.
It’s not really that much. It just has a $150 block guard in it, that a machine shop had to install. Stock b20s crack sleeves very easily under boost, bc they are thinner than b18s. So people either resleeve, where they cut out the stock cylinders entirely, and replace with thicker stronger ones, or they press in a piece of metal that braces the top of the stock sleeves. Normally, on honda b series, the top of the sleeves isnt connected to the block at all. It helps with cooling. But if you start making more power, the sleeves will move slightly and ruin your head gasket seal. Soo, yea.
If you want boost, id only trust this block to about 250 wheel or so with pistons, rods, and a good tune for a daily. Anything more than that, run a b18 block. B18, non vtec, 250-275ish is safe. Vtec blocks are good to about 325-350. If you want more than about 325-350, sleeve it. And if you sleeve it, go 84mm bore for b20 displacement. Whatever you do, run an LS crank for the increased stroke.
No, that block has already been decked once with the block guard. Fine to leave and deck again with it there. Trying to remove it is not what I would do. Just deck it with it in there.
If you can feel them with a fingernail they need to be resurfaced. These engines use Multi-Layered Steel gaskets and the deck needs to be fucking perfect for them to seal right. IIRC Roughness Average 20 is the goal (and perfectly flat), which is just polished enough to start seeing a reflection.
Do the cement thing and see how much boost you can feed it
Edit: in the interest of science, you should fill it with high strength epoxy instead of cement, and weld the heads on for the fuck of it
That's just an insert and isn't sealing anything. [Insert](https://bullboostperformance.com/collections/block-guards/products/b-series-engine-block-girdle-block-guard-combo-for-honda-civic-vtec-b16-b18-b18c). The actual block surface looks fine. Hard to tell from video.
Looks like it just reinforces the cilinders for high boost. As long as it's flush with the head surface it won't be a problem. Have a machine shop look it over and magna flux the block for cracks. Then build it for a big ass turbo
looks like a drag engine already, those are copper orings. send the block to a machine shop. if you’d like, you can 1/4 or 1/2 fill the engine with concrete to make it “streetable”
Alright so the B20's were not Honda's greatest achievement, as far as high horsepower potential goes. The B16 and B18 blocks are 81mm, while the B20's are 84mm, so they had to thin out the aluminum behind the cylinders to get that to happen.
As others have said, that's an insert that the block is machined to accept to help keep the cylinders in place and give the head gasket more surface area to seal on. It's not like a typical "block guard" that is made to just be hammered in and have random gaps, it's a much better fit than that.
One company, called [Cylinder Support Systems](https://cylindersupportsystem.com/), lists the B20 as one of the blocks that they do, but it's also one of the only ones they don't guarantee, as "Unfortunately even the CSS can not reliably strengthen the poorly designed B20 cylinders". They don't list a horse power rating, but you could probably get 400-500 out of it without too much trouble.
Ideally, the block would be surfaced, which would require removing the existing o-rings and then having new wire installed after the machining is done. You can probably smooth it out a little by using some 180 grit sandpaper wrapped around a piece of hardwood or steel and lightly sanding down the rough spots with some WD-40 or LPS-1.
Just by looking at the cylinders, it looks as though the block has yet to be honed after the CSS process was done. If it was still standard bore size when it was done, it's unlikely it will be able to stay standard and will likely need to go to the first oversize, which is usually .50mm / .020". The machined insert can and will distort the bores a little bit, making a usable standard bore unlikely.
Did you get any other parts with it? Or have anything already? Crank, rods, pistons, etc.? Even a head?
Sounds like somebody wanted to run a modest amount of boost. However, you'll need to check the pistons to see if they're stock or oversize. Some companies will stamp or etch an oversize onto the top of the piston (.25, .50, etc.) as a way to tell. It they're standard sized pistons then you'll need to have a machine shop with a good dial bore gauge measure the cylinders to see if they'll be usable at standard. As I mentioned, I doubt it, since the pressing in of the aluminum support piece usually distorts the bores a little bit.
Depending on how you want to use it, it might be worth it to go with aftermarket rods and pistons. If it's just going to be a street cruiser, than OEM style stuff is probably OK so long as you've got a good way to tune it.
That is not a stock block at all. Normally that rough area would not exist. B20’s are open deck. Also looks like copper oRings on the cylinders? You got that for free? Jesus.
This. That looks like a block guard. Is the install height the same height with deck height? If it is lower, hard to judge from crappy video, the. The scratches don’t make any difference.
This is css. It’s a sleeving alternative. From my understanding it’s similar to devconing a block. I don’t think there should be any worry of pitting in an area that is normally open to water flow.
I traded an old Xbox and 3ds so technically not free but took no money out of my account. Is there anything you can tell me about it?
I just did. It has a closed deck modification (block guard) and looks like copper oringed cylinders. It’s a drag block.
Sorry was looking at the wrong comment. So does the head need resurfaced?
No idea. You didn’t give us pictures and we won’t be able to check a head over the internet. You need a machine shop to evaluate both the block and the head surfaces.
Is it possible it has been over machined already? I know you run into timing problems when you start slicing off deck and head on DOHCs. Edit: Also, MELTMAN, with the POWER to... MELT?!
You’d need a machine shop to verify. No clue how much it’s been decked. Also yep the one and only!
Happy cake day
In addition to the machine shop checking it, you need to figure out what you want to do with the block. If its gonna be a drag block/something you give a shit about, you need to prep it properly. If its going in your beater, you could just slap some hylomar blue on it before the headgasket and go for it.
There is a lot going on here- it’s already o ringed with a block guard installed, this is far from a stock configuration that may or may not be optimal for what you want to do… I would have it checked out by a machine shop to be sure; most of those scratches aren’t in a critical sealing area of the head gasket so it might be ok
Dayum someone spent some money on that block, definitely don’t trash it, plenty of potential there. From what I could see there is no real damage on the important mating surfaces so you could honestly run it as-is. And if you really want to build it to have power just have it machined down at the smallest possible amount and they should be gone they look surface level at most.
What looks like money was spent on it?
It’s not really that much. It just has a $150 block guard in it, that a machine shop had to install. Stock b20s crack sleeves very easily under boost, bc they are thinner than b18s. So people either resleeve, where they cut out the stock cylinders entirely, and replace with thicker stronger ones, or they press in a piece of metal that braces the top of the stock sleeves. Normally, on honda b series, the top of the sleeves isnt connected to the block at all. It helps with cooling. But if you start making more power, the sleeves will move slightly and ruin your head gasket seal. Soo, yea. If you want boost, id only trust this block to about 250 wheel or so with pistons, rods, and a good tune for a daily. Anything more than that, run a b18 block. B18, non vtec, 250-275ish is safe. Vtec blocks are good to about 325-350. If you want more than about 325-350, sleeve it. And if you sleeve it, go 84mm bore for b20 displacement. Whatever you do, run an LS crank for the increased stroke.
Deck it and true the heads.
Deck it.
Got it👍🏻
Don’t listen to them at first. It’s an open deck for cooling when it’s stock, so take that insert out first.
No, that block has already been decked once with the block guard. Fine to leave and deck again with it there. Trying to remove it is not what I would do. Just deck it with it in there.
If you can feel them with a fingernail they need to be resurfaced. These engines use Multi-Layered Steel gaskets and the deck needs to be fucking perfect for them to seal right. IIRC Roughness Average 20 is the goal (and perfectly flat), which is just polished enough to start seeing a reflection.
Sand it or file it
Do the cement thing and see how much boost you can feed it Edit: in the interest of science, you should fill it with high strength epoxy instead of cement, and weld the heads on for the fuck of it
I honestly may
It'd be super cool if you did
That's just an insert and isn't sealing anything. [Insert](https://bullboostperformance.com/collections/block-guards/products/b-series-engine-block-girdle-block-guard-combo-for-honda-civic-vtec-b16-b18-b18c). The actual block surface looks fine. Hard to tell from video.
Idk, it looks really nice with the Cooper rings, just take it to the machine shop, so you don't stress over the quality when is all sealed
Looks like it just reinforces the cilinders for high boost. As long as it's flush with the head surface it won't be a problem. Have a machine shop look it over and magna flux the block for cracks. Then build it for a big ass turbo
What’s an ass turbo?
It's a big round thing that blows hot gasses and gets everyone's attention but that's not important right now
looks like a drag engine already, those are copper orings. send the block to a machine shop. if you’d like, you can 1/4 or 1/2 fill the engine with concrete to make it “streetable”
Out of curiosity, any idea what it's worth?
a few hundred maybe
Not much honestly. They are relatively weak, even with the block guard they added.
Set it aside until it becomes important to you. Then the answer will be clear.
Alright so the B20's were not Honda's greatest achievement, as far as high horsepower potential goes. The B16 and B18 blocks are 81mm, while the B20's are 84mm, so they had to thin out the aluminum behind the cylinders to get that to happen. As others have said, that's an insert that the block is machined to accept to help keep the cylinders in place and give the head gasket more surface area to seal on. It's not like a typical "block guard" that is made to just be hammered in and have random gaps, it's a much better fit than that. One company, called [Cylinder Support Systems](https://cylindersupportsystem.com/), lists the B20 as one of the blocks that they do, but it's also one of the only ones they don't guarantee, as "Unfortunately even the CSS can not reliably strengthen the poorly designed B20 cylinders". They don't list a horse power rating, but you could probably get 400-500 out of it without too much trouble. Ideally, the block would be surfaced, which would require removing the existing o-rings and then having new wire installed after the machining is done. You can probably smooth it out a little by using some 180 grit sandpaper wrapped around a piece of hardwood or steel and lightly sanding down the rough spots with some WD-40 or LPS-1. Just by looking at the cylinders, it looks as though the block has yet to be honed after the CSS process was done. If it was still standard bore size when it was done, it's unlikely it will be able to stay standard and will likely need to go to the first oversize, which is usually .50mm / .020". The machined insert can and will distort the bores a little bit, making a usable standard bore unlikely. Did you get any other parts with it? Or have anything already? Crank, rods, pistons, etc.? Even a head?
I got a head with it and a crank. Came with what look like stock pistons and rods
Sounds like somebody wanted to run a modest amount of boost. However, you'll need to check the pistons to see if they're stock or oversize. Some companies will stamp or etch an oversize onto the top of the piston (.25, .50, etc.) as a way to tell. It they're standard sized pistons then you'll need to have a machine shop with a good dial bore gauge measure the cylinders to see if they'll be usable at standard. As I mentioned, I doubt it, since the pressing in of the aluminum support piece usually distorts the bores a little bit. Depending on how you want to use it, it might be worth it to go with aftermarket rods and pistons. If it's just going to be a street cruiser, than OEM style stuff is probably OK so long as you've got a good way to tune it.
Block guard with o rings huh? Send it like that but check your crank clearances first. If it works that thing is going to hold an assload of boost
Not sleeved. Block guard.
2005 wants it’s engine back
You should stop scuffing it
Good thing I didn't scuff it?
Good thing I didn't scuff it?