I Thought it was a noisy forged build but now I'm not sure?
#151
Scooby Regular
iTrader: (1)
Looks like the shock of detting has caused that piston to fail, not so good mate hopefully the rods are fine and you get it built back up again.
I had cosworth pistons in my v3 running 520bhp but they were really noisy even warm but could have been the way it was built.
I had cosworth pistons in my v3 running 520bhp but they were really noisy even warm but could have been the way it was built.
Last edited by **jay**; 26 April 2016 at 06:32 PM.
#152
Thanks jay
I'm going to start building up this standard donor block so I can get back on the road,I will still have to use my big turbo,injectors etc but I will just put a safe map on there.
I can take my time then and do a slow build over the summer.
I will do a bit more reading up on the cosworth stuff but it's a good name for quality so my best option looks like trying to get hold of a matching piston for the build.
From what I can see and feel,the rods look ok and there is no play in the bearings.
I'm itching to split the block to see everything in the flesh but need to get running asap so will have to wait.
I'm going to start building up this standard donor block so I can get back on the road,I will still have to use my big turbo,injectors etc but I will just put a safe map on there.
I can take my time then and do a slow build over the summer.
I will do a bit more reading up on the cosworth stuff but it's a good name for quality so my best option looks like trying to get hold of a matching piston for the build.
From what I can see and feel,the rods look ok and there is no play in the bearings.
I'm itching to split the block to see everything in the flesh but need to get running asap so will have to wait.
#154
Scooby Regular
iTrader: (5)
I've got cosworth pistons and rods in mine and it's very noisy, has been from the beginning. I think omega are regarded by many as top quality pistons but cosworth has the bigger name. I don't believe they make them in house though, possibly made in China.
Be sure to have the rods and crank inspected and checked for ovalling.
Good luck
Be sure to have the rods and crank inspected and checked for ovalling.
Good luck
#155
You're not wrong there mate,made a bit of a mess
Cheers for the tips ganzey,would I be able to check or would they need to be inspected by a specialist?
I've got cosworth pistons and rods in mine and it's very noisy, has been from the beginning. I think omega are regarded by many as top quality pistons but cosworth has the bigger name. I don't believe they make them in house though, possibly made in China.
Be sure to have the rods and crank inspected and checked for ovalling.
Good luck
Be sure to have the rods and crank inspected and checked for ovalling.
Good luck
#157
Scooby Regular
iTrader: (13)
Different pistons expand to a lesser or greater extent once they get heat in them.
So some need more room in the bore to expand.
I have had engines with many of the different types in inculding Omega (which are a quality item)
How quiet an engine is ...is obviously also often down to how well it is machined/built.
So given that an engine is a good one and has been built with the right tolerances
The quietest forged piston I have come across are Mahle.
I would also add that certain Cosworth stuff is made elsewhere and then branded Cosworth. I am not saying it is not good, as they have a quality brand name to protect.
Omegas in my experience were quite noisy when cold and they needed a bit of room to expand and sounded as sweet as once warmed up and the thing was being thrashed. (It is a while since I have had any in a Subaru engine...so a builder that has used them recently would be better placed to comment)
So some need more room in the bore to expand.
I have had engines with many of the different types in inculding Omega (which are a quality item)
How quiet an engine is ...is obviously also often down to how well it is machined/built.
So given that an engine is a good one and has been built with the right tolerances
The quietest forged piston I have come across are Mahle.
I would also add that certain Cosworth stuff is made elsewhere and then branded Cosworth. I am not saying it is not good, as they have a quality brand name to protect.
Omegas in my experience were quite noisy when cold and they needed a bit of room to expand and sounded as sweet as once warmed up and the thing was being thrashed. (It is a while since I have had any in a Subaru engine...so a builder that has used them recently would be better placed to comment)
Last edited by Steve Whitehorn; 26 April 2016 at 10:12 PM.
#159
Couldn't feel anything but I see what you mean when I look at the pics again,as its damaged at the bottom of the cyl then it will be getting scrapped anyway.
Will do Steve thanks,going to take my time with the build.
This donor short block should keep me going for a good while,I will clean my heads and sump up as they will be needed for the donor
Not sure if I need to use my Modine as I'm twin scroll,will look into that.
Also might use my oil pump too,not sure yet?
This donor short block should keep me going for a good while,I will clean my heads and sump up as they will be needed for the donor
Not sure if I need to use my Modine as I'm twin scroll,will look into that.
Also might use my oil pump too,not sure yet?
#161
I will leave that modine on then mate if it's only done 5k
Do you know if there's any difference with twin scroll cars modine or would the one on your block be ok for my setup?
#164
Yes ganzey the donor block suffered head gasket failure.
I know most people advise to refresh the bearings after a head gasket has gone but time and funds won't allow this right now,I will just have to take the chance and hope I'm lucky.
I'm sure there are plenty of cases where head gasket failure doesn't always lead to the bottom end failure so I will just have to keep my fingers crossed.
I know most people advise to refresh the bearings after a head gasket has gone but time and funds won't allow this right now,I will just have to take the chance and hope I'm lucky.
I'm sure there are plenty of cases where head gasket failure doesn't always lead to the bottom end failure so I will just have to keep my fingers crossed.
#166
But I've only paid £48 for standard oem head gaskets so all in all it will come in at under £100 to get this donor up and running,plus my time and a few scraped knuckles which I don't mind.
#167
Good advice mate and I will defiantly be taking my time and using quality updated items to rebuild the forged block.
But I've only paid £48 for standard oem head gaskets so all in all it will come in at under £100 to get this donor up and running,plus my time and a few scraped knuckles which I don't mind.
But I've only paid £48 for standard oem head gaskets so all in all it will come in at under £100 to get this donor up and running,plus my time and a few scraped knuckles which I don't mind.
Ask any engine builders on here about bearing failure after HG. There is a reason they refuse to do just headgaskets.
You will end up with a car off the road in the near future I am sure, and end up in exactly the same situation as you are now. Honestly the best advice is buy a ****ter and don't bother with the temporary block.
It will end up costing twice as much and it is essentially money down the pan. I'd rather have something reliable and build the scoob up as and when and do it properly.
In all my years of modifying cars, the one thing I have learnt is temporary never works. Build for permanent.
#168
It's defiantly not ideal JGV but I now have all the parts,gaskets etc.
If I bought a runabout+insurance+keeping the Scooby insured it's going to work out at more than £100.
I'm not ignoring advice as it all makes sense but I've started building up the temp engine and the gaskets I've bought can't/won't be used on the forged build.
I suppose I'm not paying for any labour so that's a big chunk of money saved,also have all the equipment needed plus I'm getting quite good at removing the engine now.
Like I say fingers will be firmly crossed and hope for a bit of good luck.
If I bought a runabout+insurance+keeping the Scooby insured it's going to work out at more than £100.
I'm not ignoring advice as it all makes sense but I've started building up the temp engine and the gaskets I've bought can't/won't be used on the forged build.
I suppose I'm not paying for any labour so that's a big chunk of money saved,also have all the equipment needed plus I'm getting quite good at removing the engine now.
Like I say fingers will be firmly crossed and hope for a bit of good luck.
#169
It's defiantly not ideal JGV but I now have all the parts,gaskets etc.
If I bought a runabout+insurance+keeping the Scooby insured it's going to work out at more than £100.
I'm not ignoring advice as it all makes sense but I've started building up the temp engine and the gaskets I've bought can't/won't be used on the forged build.
I suppose I'm not paying for any labour so that's a big chunk of money saved,also have all the equipment needed plus I'm getting quite good at removing the engine now.
Like I say fingers will be firmly crossed and hope for a bit of good luck.
If I bought a runabout+insurance+keeping the Scooby insured it's going to work out at more than £100.
I'm not ignoring advice as it all makes sense but I've started building up the temp engine and the gaskets I've bought can't/won't be used on the forged build.
I suppose I'm not paying for any labour so that's a big chunk of money saved,also have all the equipment needed plus I'm getting quite good at removing the engine now.
Like I say fingers will be firmly crossed and hope for a bit of good luck.
I hope it works out for you Rich! Fingers crossed
#175
On inspecting one of the other pistons I have found fracture lines in exactly the same place as the one that failed! So I won't be reusing them now.
#176
Scooby Regular
iTrader: (2)
I have mahle pistons in mine and you wouldn't know theyre in there even when cold. I reused the modine on my build but It wasn't a blown engine just worn out and badly built. I placed a magnet inside the modine to see if there was any swarf and vacuumed the inside using a small peice of pipe. How did you measure for the head gaskets? Because I wasn't confident measuring and didn't trust the local machine shops I handed the long block assembly and machining to a pro. His labour charges were a very small part of the build. He also supplied parts at similar oft. Lower price to what I could buy them online.
Check the crank hasn't been ground and fitted with os bearings, subarus don't respond well to ground cranks. Reusing the oil pump shouldn't be an issue as long as the prv isn't sticking.
I've yet to be convinced that subaru engines can be built on a tight budget. A diy refresh with rings bearings gaskets and a hone is going to cost over a grand.
Check the crank hasn't been ground and fitted with os bearings, subarus don't respond well to ground cranks. Reusing the oil pump shouldn't be an issue as long as the prv isn't sticking.
I've yet to be convinced that subaru engines can be built on a tight budget. A diy refresh with rings bearings gaskets and a hone is going to cost over a grand.
#177
I just went for standard 1.6mm gaskets edsel.
It's a standard donor block I'm using with my standard heads so was thinking this would be ok.
This is just for short term,saying that it might be in for a while?
As I need a new block and now after inspecting one the other Pistons I have taken out,it has fracture lines in the same place the other failed so they will be going in the bin too!
Might just end up saving for a proper pro build for long term,need to have a think.
It's a standard donor block I'm using with my standard heads so was thinking this would be ok.
This is just for short term,saying that it might be in for a while?
As I need a new block and now after inspecting one the other Pistons I have taken out,it has fracture lines in the same place the other failed so they will be going in the bin too!
Might just end up saving for a proper pro build for long term,need to have a think.
Last edited by ossett2k2; 27 April 2016 at 10:13 PM.
#178
Well finally the engine's built back up and I fitted it today,all done
I still have to wait a little longer to turn the key tho.
Was hoping for my delivery from opie today,oil,filter,coolant but sadly it didn't turn up
Guess I've waited this long so a few more days won't hurt,proper looking forward to driving it again
I still have to wait a little longer to turn the key tho.
Was hoping for my delivery from opie today,oil,filter,coolant but sadly it didn't turn up
Guess I've waited this long so a few more days won't hurt,proper looking forward to driving it again