Cosworth is manufacturing new YB Alloy Engine Blocks AND YB cylinder head (page 2)
#43
Torsional rigidity and overall strength, aluminium is weaker than cast iron.
Hypothetically, if the alloy block was cast using the original cast iron mould, would it not be weaker ?
I know the have introduced more metal to the stud areas but the block wall thickness is less.
When Ford and Harts did the BDT and BDT/E four bolt main caps were used and much more metal was introduced to strengthen the block in the main bearing area and a dry deck format was used to improve the rigidity of the deck face.
Steve
Hypothetically, if the alloy block was cast using the original cast iron mould, would it not be weaker ?
I know the have introduced more metal to the stud areas but the block wall thickness is less.
When Ford and Harts did the BDT and BDT/E four bolt main caps were used and much more metal was introduced to strengthen the block in the main bearing area and a dry deck format was used to improve the rigidity of the deck face.
Steve
Be interesting to see some figures to back up your suspicicions........and some proof they just used the old mould????????
#44
Taken from Mark Sheads post on this thread:
This quote is taken from the reply from Cosworth USA. So it's not a Millington block, but should have some similarities maybe.
Although only a handful of these blocks have been sold and are currently running (because the block has only recently released), there is 15 years of experience and knowledge that has gone into the design of the block by an ex-Millington employee. This direct replacement block has been under development for the last three years.
#45
There was a great program on channel 4 in the eighties called equinox and they followed the beatrice team and cosworth developing a 4 pot turbo engine for a f1 car based on a BD alloy block engine.
Every time they tried to give it some beans on the dyno it shit itself big time - it turned out the block was twisting and siezing the engine, and that was on the dyno without the extra stresses of being sat in a car. In the end they scrapped the idea and built a v6 instead.
Cosworth seemed quite vague in answering Marks questions which does suggest its quite correct that they are only marketing it.
If cosworth had built it then no doubt they would have made another batch of 200 blocks as well, and this has not happened
I think when people compare it to other alloy blocked engines they must remember they were designed as alloy blocks from the outset.
Probably ideal for a lightweight mid spec engine, but not for a big bhp beast
Every time they tried to give it some beans on the dyno it shit itself big time - it turned out the block was twisting and siezing the engine, and that was on the dyno without the extra stresses of being sat in a car. In the end they scrapped the idea and built a v6 instead.
Cosworth seemed quite vague in answering Marks questions which does suggest its quite correct that they are only marketing it.
If cosworth had built it then no doubt they would have made another batch of 200 blocks as well, and this has not happened
I think when people compare it to other alloy blocked engines they must remember they were designed as alloy blocks from the outset.
Probably ideal for a lightweight mid spec engine, but not for a big bhp beast
#46
There was a great program on channel 4 in the eighties called equinox and they followed the beatrice team and cosworth developing a 4 pot turbo engine for a f1 car based on a BD alloy block engine.
Every time they tried to give it some beans on the dyno it shit itself big time - it turned out the block was twisting and siezing the engine, and that was on the dyno without the extra stresses of being sat in a car. In the end they scrapped the idea and built a v6 instead.
Cosworth seemed quite vague in answering Marks questions which does suggest its quite correct that they are only marketing it.
If cosworth had built it then no doubt they would have made another batch of 200 blocks as well, and this has not happened
I think when people compare it to other alloy blocked engines they must remember they were designed as alloy blocks from the outset.
Probably ideal for a lightweight mid spec engine, but not for a big bhp beast
Every time they tried to give it some beans on the dyno it shit itself big time - it turned out the block was twisting and siezing the engine, and that was on the dyno without the extra stresses of being sat in a car. In the end they scrapped the idea and built a v6 instead.
Cosworth seemed quite vague in answering Marks questions which does suggest its quite correct that they are only marketing it.
If cosworth had built it then no doubt they would have made another batch of 200 blocks as well, and this has not happened
I think when people compare it to other alloy blocked engines they must remember they were designed as alloy blocks from the outset.
Probably ideal for a lightweight mid spec engine, but not for a big bhp beast
Why should Cosworth make a cast iron 200 block, when they have a more modern light weight aluminium alloy block?
#48
because there is a big market for sub Ł1000 cast blocks with proven capability and a very small market for Ł3650 alloy ones with none.
If I was spending nearly 4k on a block I would want a lot more back up as to its capabilities from cosworth than they seem to be offering
#49
#50
They did not use the same mould, that is not what I said.
I have never found aluminium to be stiffer than cast iron.
Steve
#51
There was a great program on channel 4 in the eighties called equinox and they followed the beatrice team and cosworth developing a 4 pot turbo engine for a f1 car based on a BD alloy block engine.
Every time they tried to give it some beans on the dyno it shit itself big time - it turned out the block was twisting and siezing the engine, and that was on the dyno without the extra stresses of being sat in a car. In the end they scrapped the idea and built a v6 instead.
Cosworth seemed quite vague in answering Marks questions which does suggest its quite correct that they are only marketing it.
If cosworth had built it then no doubt they would have made another batch of 200 blocks as well, and this has not happened
I think when people compare it to other alloy blocked engines they must remember they were designed as alloy blocks from the outset.
Probably ideal for a lightweight mid spec engine, but not for a big bhp beast
Every time they tried to give it some beans on the dyno it shit itself big time - it turned out the block was twisting and siezing the engine, and that was on the dyno without the extra stresses of being sat in a car. In the end they scrapped the idea and built a v6 instead.
Cosworth seemed quite vague in answering Marks questions which does suggest its quite correct that they are only marketing it.
If cosworth had built it then no doubt they would have made another batch of 200 blocks as well, and this has not happened
I think when people compare it to other alloy blocked engines they must remember they were designed as alloy blocks from the outset.
Probably ideal for a lightweight mid spec engine, but not for a big bhp beast
I remember watching this as a nipper......I was fascinated. Me and my dad watched it......awesome programme. I would LOVE a copy of it
#52
Yes ordered and paid this morning hope to not need luck unlike buying used yb engines.
#53
PassionFord Post Whore!!
Joined: Sep 2003
Posts: 4,519
Likes: 1
From: Macclesfield - you'll never leave....!
#54
#55
would be nice to actualy get some of the tuners at a table with the cosworth bods so the tuners can give there understanding on things as they have seen
as im sure people like mark,martin,karl have gone further with the engine than cosworth intended
as far as cosworth knew 500 race spec was as far as it went till tuners went further
cosworth proberbly could have gone further but didnt need to as nothing could catch there cars anyway
as im sure people like mark,martin,karl have gone further with the engine than cosworth intended
as far as cosworth knew 500 race spec was as far as it went till tuners went further
cosworth proberbly could have gone further but didnt need to as nothing could catch there cars anyway
#56
As Steve said, aluminium is not stiffer than cast iron.
The advantage with aluminium is that you can use more of it to create better shapes that will make the component stronger for the same weight.
The problem i have with the ally YB block shown in this thread is that externally it looks just like a cast iron YB block to my un YB experienced eye. It has no extra webbing/bracing/gussets on the outside and i doubt neither round the bores/water jacket.
From this i can only come to the conclusion that it will be lighter but NOT stronger than the cast iron block.
IMO if cosworth were going to do a proper ally replacement of the YB block they would have to totally re engineer the block design, not start with the basic cast iron design. If you look at a purpose built ally block they are totally different with features like the crank being placed higher up in the block.
The advantage with aluminium is that you can use more of it to create better shapes that will make the component stronger for the same weight.
The problem i have with the ally YB block shown in this thread is that externally it looks just like a cast iron YB block to my un YB experienced eye. It has no extra webbing/bracing/gussets on the outside and i doubt neither round the bores/water jacket.
From this i can only come to the conclusion that it will be lighter but NOT stronger than the cast iron block.
IMO if cosworth were going to do a proper ally replacement of the YB block they would have to totally re engineer the block design, not start with the basic cast iron design. If you look at a purpose built ally block they are totally different with features like the crank being placed higher up in the block.
#57
in my oppinion as iv said before the best option for big bhp is a cgi block not alloy
iv looked at doing a gurdle and 4 bolt mains in the oe cosworth block and without going through the oil ways you cant through bolt it
if they where to make the galleries in a different way it would be possible
iv looked at doing a gurdle and 4 bolt mains in the oe cosworth block and without going through the oil ways you cant through bolt it
if they where to make the galleries in a different way it would be possible
#58
hanging the crank out the bottom of the block just held up my the mains which then have no support from the side is a bad design in the first place, a girdle will help, but even thats not as good as it can be with an intergrated carrier for all the mains caps that positively located onto the block.
Its very out of date technology essentially from a block point of view, from the 60s and intended for a low specific output.
Its very out of date technology essentially from a block point of view, from the 60s and intended for a low specific output.
#60
http://www.engineeringtoolbox.com/yo...lus-d_773.html
I have always been led to believe that it is.
I'm reasonably experienced with engineering mountain bikes rigid or suspended and the trade off between weight, stiffness and volume of parts and i know a bit about the properties of various metals, heat treating etc etc
I have always been led to believe that it is.
I'm reasonably experienced with engineering mountain bikes rigid or suspended and the trade off between weight, stiffness and volume of parts and i know a bit about the properties of various metals, heat treating etc etc
Its versus volume NOT weight you need to be considering when both are from the same mould (or very similar)
When was the last time you saw aluminium bolts instead of steel for a stressed application?
#63
I'm not sure you understand YME. The figures in the link you provide show that cast iron will require over twice the force of aluminium to deform.
Tensile strength of a material plays a huge factor in the deisgn of a block. What do you think the combustion forces are doing if they are not trying to pull the material around the bore apart?
Tensile strength of a material plays a huge factor in the deisgn of a block. What do you think the combustion forces are doing if they are not trying to pull the material around the bore apart?
#64
#65
after all Millington made blocks for years...used in high rpm applications and Martins first Escort used one and that was a high boost application. Martin seems to know something about this new block too so perhaps theres something to be said for it, without testing or a very good look at it you just wont know
Last edited by It's Czech Mate; 12-11-2008 at 10:58 AM.
#68
#70
That graph shows the modulus of elasticity against temp as you can see alu alloy is three times stiffer than steel and the table below shows its significantly stiffer than grey cast iron so i'm not sure you do to be honest.
I never mentioned tensile strength......it would come into play if the blocks were cracking for sure...but if they are more resistant to twisting ( due to being stiffer - see the youngs modulus of the materials ) then the tensile strength becomes less of an issue
I dont claim to know any of the figures or facts but i assure you alu alloy is generally stiffer than cast iron and i just countered someone saying the block twists with the fact the alloy block 'should' be stiffer
after all Millington made blocks for years...used in high rpm applications and Martins first Escort used one and that was a high boost application. Martin seems to know something about this new block too so perhaps theres something to be said for it, without testing or a very good look at it you just wont know
I never mentioned tensile strength......it would come into play if the blocks were cracking for sure...but if they are more resistant to twisting ( due to being stiffer - see the youngs modulus of the materials ) then the tensile strength becomes less of an issue
I dont claim to know any of the figures or facts but i assure you alu alloy is generally stiffer than cast iron and i just countered someone saying the block twists with the fact the alloy block 'should' be stiffer
after all Millington made blocks for years...used in high rpm applications and Martins first Escort used one and that was a high boost application. Martin seems to know something about this new block too so perhaps theres something to be said for it, without testing or a very good look at it you just wont know
Look at the rest of the table for proof. Are you suggesting copper is less elastic than steel or tungsten????
Cast iron MAY have a lower yeild strength than ally but until that point it is less elastic.
#71
Maybe I should get a comission from Cosworth USA for posting this thread...??!!
Best of luck with it. Let us know when you receive and post up some photos of it.
#72
#73
#74
All the discussion aside it boils down to whats been said already. We wont know anything untill someone gets a good look at the new block.....it appears that unless the casting is significantly different to the old one then it 'may' be unsuitable....however as Martoon knows something about it and it has Millington experience behind it there may be a nice surprise in store
#75
"Where failure is not an issue but excessive flex is undesirable due to requirements for precision of location, or efficiency of transmission of power, simple replacement of steel tubing with similarly sized aluminium tubing will result in a degree of flex which is undesirable; for instance, the increased flex under operating loads caused by replacing steel bicycle frame tubing with aluminium tubing of identical dimensions will cause misalignment of the power-train as well as absorbing the operating force. To increase the rigidity by increasing the thickness of the walls of the tubing increases the weight proportionately, so that the advantages of lighter weight are lost as the rigidity is restored.
In such cases, aluminium may best be used by redesigning the dimension of the part to suit its characteristics; for instance making a bicycle frame of aluminium tubing that has an oversize diameter rather than thicker walls. In this way, rigidity can be restored or even enhanced without increasing weight."
Confirms what i have said previously in the post about designing aluminium components.
In such cases, aluminium may best be used by redesigning the dimension of the part to suit its characteristics; for instance making a bicycle frame of aluminium tubing that has an oversize diameter rather than thicker walls. In this way, rigidity can be restored or even enhanced without increasing weight."
Confirms what i have said previously in the post about designing aluminium components.
#76
Is it just me or is anyone else wondering why Cosworth have gone to the trouble to re-manufacture the blocks but not the heads???
I would have thought if they were going to make one or the other they would have done the heads first as 2nd ones are going for big money (as seen on a recent thread) and there not even the very good one's. Decent blocks dont seem to be difficult to source.
Maybe they will do the heads now if the blocks start selling well.
I would have thought if they were going to make one or the other they would have done the heads first as 2nd ones are going for big money (as seen on a recent thread) and there not even the very good one's. Decent blocks dont seem to be difficult to source.
Maybe they will do the heads now if the blocks start selling well.
#78
the crank can only realy go any where on its down stroke as the upper part of the block is too thick to push through and the crancks inertia dosnt go to the side as strongly
the best way would be as chip says an intergrated ladder section with through bolts holding it together
the problem is that the block cant take through bolts at all because of the oil ways .the only way round this is to rethink it all together making id different to the yb all together
the best way would be as chip says an intergrated ladder section with through bolts holding it together
the problem is that the block cant take through bolts at all because of the oil ways .the only way round this is to rethink it all together making id different to the yb all together
#79
Is it just me or is anyone else wondering why Cosworth have gone to the trouble to re-manufacture the blocks but not the heads???
I would have thought if they were going to make one or the other they would have done the heads first as 2nd ones are going for big money (as seen on a recent thread) and there not even the very good one's. Decent blocks dont seem to be difficult to source.
Maybe they will do the heads now if the blocks start selling well.
I would have thought if they were going to make one or the other they would have done the heads first as 2nd ones are going for big money (as seen on a recent thread) and there not even the very good one's. Decent blocks dont seem to be difficult to source.
Maybe they will do the heads now if the blocks start selling well.
Should be good news for YB tuning. Now you can build a new YB engine and have a brand new Cosworth alloy block with a brand spanking new Cosworth YB 4wd spec head on top...
#80
Actually Cosworth has recast the YB head as well. They are now in the process of machining them to 4wd spec.
Should be good news for YB tuning. Now you can build a new YB engine and have a brand new Cosworth alloy block with a brand spanking new Cosworth YB 4wd spec head on top...
Should be good news for YB tuning. Now you can build a new YB engine and have a brand new Cosworth alloy block with a brand spanking new Cosworth YB 4wd spec head on top...
Only any good for the scene if the block can take big power IMHO, and Im still very skeptical about that personally.