Big end bearing upgrade worth it?
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From: 32 cylinders and many cats
"If" I was doing an EJ20 rebuild (planning to stick to 2.0 litre) for 1.8 bar with head bolts, pistons, rods, do you think it is worth upgrading the big end bearings (& why?) and what options are available? I know there are a squillion and one things I could do, I am trying to identify the things I really want to do without going bonkers.
Upgrading to what though??? Strictly speaking the crank should never touch the bearings anyway, and the standard bearings dont really give any problems. The big end failures are not down to bearing type, I would say with certainty.
When I rebuilt my car, I just used Aussie made ACL Duraglide bearings, sourced locally, and about half the price of OE Subaru ones.
When I rebuilt my car, I just used Aussie made ACL Duraglide bearings, sourced locally, and about half the price of OE Subaru ones.
without going bonkers.
too late if you are thinking like this
,the rest of the cars not 1.8bar safe unless you are driving like a granny.
I think you would need to do the sums to make the complete car 1.8 bar safe,then decide how long it will be before you want 2bar.
too late if you are thinking like this
,the rest of the cars not 1.8bar safe unless you are driving like a granny.I think you would need to do the sums to make the complete car 1.8 bar safe,then decide how long it will be before you want 2bar.
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From: 32 cylinders and many cats
Thanks Steve, so I should just leave them alone since they are presumably in good nick? The decision is whether to do a planned or unplanned engine rebuild.
Don't worry T-uk I won't run 1.8 bar on your turbo
I'll change the clutch and lighten the flywheel whilst I am there if I go for this.
Bones break, driveshafts die, what the hell
Sounding like Gridlock Mikey now
Don't worry T-uk I won't run 1.8 bar on your turbo

I'll change the clutch and lighten the flywheel whilst I am there if I go for this.
Bones break, driveshafts die, what the hell
Sounding like Gridlock Mikey now
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From: Leeds - It was 562.4bhp@28psi on Optimax, How much closer to 600 with race fuel and a bigger turbo?
Was it reading my email that did it?
I presume you mean studs and not bolts?
My theory was if your going to do it then you might as well do it whilst its in bits..
Id put new bearings in anyway if doing a rebuild..
David
I presume you mean studs and not bolts?
My theory was if your going to do it then you might as well do it whilst its in bits..
Id put new bearings in anyway if doing a rebuild..
David
never reuse bearings no question.
stevie, just because they arent touched doesnt mean you dont uprate them.
by your reckoning you could make them out of gold leaf and it wouldnt matter.
the shock load [placed on the oil is transmitted to its surroundings which is the bearing shell, upratings can provide better longevity, but it wont solve potential big end failures.
john,
do what I did (though it didnt help me). amass the parts and keep your engine running in the meantime. If it still isnt dead when you have finished collecting then build a whole second engine, and get the ancillaries off yours when you switch them over.
Speak to mark about the bearing issue, and source yourself a 2 litre closed deck whilst you are at it.
apart from the block, the donor bits from your engine like the crank, can be sourced cheaply enough for it not to be worth not having two complete engines.
stevie, just because they arent touched doesnt mean you dont uprate them.
by your reckoning you could make them out of gold leaf and it wouldnt matter.
the shock load [placed on the oil is transmitted to its surroundings which is the bearing shell, upratings can provide better longevity, but it wont solve potential big end failures.
john,
do what I did (though it didnt help me). amass the parts and keep your engine running in the meantime. If it still isnt dead when you have finished collecting then build a whole second engine, and get the ancillaries off yours when you switch them over.
Speak to mark about the bearing issue, and source yourself a 2 litre closed deck whilst you are at it.
apart from the block, the donor bits from your engine like the crank, can be sourced cheaply enough for it not to be worth not having two complete engines.
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From: 32 cylinders and many cats
Yes David, meant head studs instead of bolts, yes your email made me consider adding the big end bearing upgrade to the list.
However, it is so easy to get into the trap of upgrading everything possible - is it so bad to just use stronger conrods and forged pistons and build it back up again?
The other option is to test the limits of the stock internals, by using a good turbo and high midrange boost.... opinions are very different.
As some have said, 300 BHP was considered the limit by many of the stock internals a year ago, now 350 BHP is a walk in the park, will it be 400 BHP this year?
Is it possible that some with "uprated" engines are suffering failures because they have replaced so many things with unproven "upgraded" parts which may not actually work together so well as even the standard stuff? Just asking the questions....
How many of those with builds have had a year or more of trouble free motoring without taking the engine out again? How many long term big bore engines are there as daily drivers?
I don't want to go down the buy a skip to drive about in route
However, it is so easy to get into the trap of upgrading everything possible - is it so bad to just use stronger conrods and forged pistons and build it back up again?
The other option is to test the limits of the stock internals, by using a good turbo and high midrange boost.... opinions are very different.
As some have said, 300 BHP was considered the limit by many of the stock internals a year ago, now 350 BHP is a walk in the park, will it be 400 BHP this year?
Is it possible that some with "uprated" engines are suffering failures because they have replaced so many things with unproven "upgraded" parts which may not actually work together so well as even the standard stuff? Just asking the questions....
How many of those with builds have had a year or more of trouble free motoring without taking the engine out again? How many long term big bore engines are there as daily drivers?
I don't want to go down the buy a skip to drive about in route
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I'll do at least rods/pistons and head studs at the end of summer if engine is still in one piece, before if not.
Does anyone know if the bottom end from a my01 has any major changes to to my00?
Richard
Does anyone know if the bottom end from a my01 has any major changes to to my00?
Richard
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From: Leeds - It was 562.4bhp@28psi on Optimax, How much closer to 600 with race fuel and a bigger turbo?
dunno.. but mark said that wire ringing could be done to reduce the chance of gasket failure on open deck blocks..
David
David
Im not saying they can be made from anything, but, what else is there available?? Ive never really had problems with any engine Ive built that have been bearing related, be it subaru or otherwise.
I have never heard of uprated bearings for a subaru, and given that the standard ones dont give trouble, then why change them to something else???
I have never heard of uprated bearings for a subaru, and given that the standard ones dont give trouble, then why change them to something else???
John
ACL bearings are what is classed as uprated, thay are lead not alloy and thay are my choice every time. The lead has a better loading, most of the time when a alloy bearing is used if it runs low on oil (for what ever reason) and fails it recks the crank and some times the rod as well creates untold swalf that recks everything else, this tends not to happen with lead. All the competition bearings that were maid in the uk used to be lead but law says that lead cant be used any more and the acl bearings are one of a few that still use lead. You can be lucky and not have a prob with alloy bearings.
Steve.
ACL bearings are what is classed as uprated, thay are lead not alloy and thay are my choice every time. The lead has a better loading, most of the time when a alloy bearing is used if it runs low on oil (for what ever reason) and fails it recks the crank and some times the rod as well creates untold swalf that recks everything else, this tends not to happen with lead. All the competition bearings that were maid in the uk used to be lead but law says that lead cant be used any more and the acl bearings are one of a few that still use lead. You can be lucky and not have a prob with alloy bearings.
Steve.
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From: 7.74 @179 mph 1/4 mile - road legal
Strange how things go the complete circle !!
When I was building racing x/flows and BDA's some years ago
the tri metal copper backed bearings were considered the 'racing' version and the lead ones were the 'standard' road car fitment !!
Agree with steve though, if a trimetal fails it generally wrecks everything around it.
When I was building racing x/flows and BDA's some years ago
the tri metal copper backed bearings were considered the 'racing' version and the lead ones were the 'standard' road car fitment !!Agree with steve though, if a trimetal fails it generally wrecks everything around it.
I cant believe john was considering a rebuild without changing the bearings?
are they that expensive that it is ever not worth changing them?
have no idea how much they cost since it was kinda incorporated into my costs without being broken down.
are they that expensive that it is ever not worth changing them?
have no idea how much they cost since it was kinda incorporated into my costs without being broken down.
I have a pic of the Teflon bearings if I can host them somewhere.
"Standard Subaru gaskets were put in, as were the factory bearings that have been Teflon-coated by HPC."
This was a rebuild done in Oz.
Trout
"Standard Subaru gaskets were put in, as were the factory bearings that have been Teflon-coated by HPC."
This was a rebuild done in Oz.
Trout
Adam,
ACL bearings are not expensive, I recently got a whole set (mains and big ends) for about UKP 100. They are one of the very few remaining copper/indium/lead bearings available, almost as good as the Vandervell VP2 bearings but sadly the Vandervells are no more, so ACL is currently about the best you can get over the counter.
I worked for a while on Vanwall business park in Maidenhead, where Vandervell used to be based, heard from some of the locals that the ground round the old factory has been poisoned by the heavy metals Vandervell were using in their bearings.... no wonder that lead bearings have become a little politically incorrect.
Cheers,
Pat.
ACL bearings are not expensive, I recently got a whole set (mains and big ends) for about UKP 100. They are one of the very few remaining copper/indium/lead bearings available, almost as good as the Vandervell VP2 bearings but sadly the Vandervells are no more, so ACL is currently about the best you can get over the counter.
I worked for a while on Vanwall business park in Maidenhead, where Vandervell used to be based, heard from some of the locals that the ground round the old factory has been poisoned by the heavy metals Vandervell were using in their bearings.... no wonder that lead bearings have become a little politically incorrect.
Cheers,
Pat.
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From: 32 cylinders and many cats
Thinking now of just changing the pistons and probably the middle head bolts. By far the cheapest/easiest option, and if I save c.25% on the piston weight and keep the rev limiter standard and make my power by 6000 RPM could be very sympathetic to the factory rods. Don't shoot me down now.... be gentle
john you are being a cheapskate.
the main cost is the labour.
if opening the thing up, you might as well do all the suspect bit.
Despite the healthy arguments andy has put forward I am still of the opinion that that rods are more important to change than the pistons.
If in doubt do both, they neednt be that expensive.
the main cost is the labour.
if opening the thing up, you might as well do all the suspect bit.
Despite the healthy arguments andy has put forward I am still of the opinion that that rods are more important to change than the pistons.
If in doubt do both, they neednt be that expensive.
John,
A 6000rpm limit and a 25% reduction in piston mass will work wonders for reliability I'm sure, but it might turn out to be a false economy in the future. I would rather try and make the bottom end as bullitproof and future mod proof as possible while you can.
A 6000rpm limit and a 25% reduction in piston mass will work wonders for reliability I'm sure, but it might turn out to be a false economy in the future. I would rather try and make the bottom end as bullitproof and future mod proof as possible while you can.
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From: 7.74 @179 mph 1/4 mile - road legal
Even I recommended John to fit uprated rods and pistons Adam 
I know what he's like
If that car isn't over 400 bhp in the next six months it can only be because it's been sold

I know what he's like
If that car isn't over 400 bhp in the next six months it can only be because it's been sold
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From: Leeds - It was 562.4bhp@28psi on Optimax, How much closer to 600 with race fuel and a bigger turbo?
It depends on whether you think there is a benefit to a closed deck block... Im not too sure.. and havent seen any proof of the bores walking / moving.. wire ring an open deck block would be my choice.. with some rods and pistons...
Ill find a link to a thread I posted...
http://www.scoobynet.co.uk/bbs/threa...hreadID=122200
David
[Edited by David_Wallis - 1/10/2003 3:07:44 PM]
Ill find a link to a thread I posted...
http://www.scoobynet.co.uk/bbs/threa...hreadID=122200
David
[Edited by David_Wallis - 1/10/2003 3:07:44 PM]
I think I read that same article in autospeed about coated bearings, tho not sure exactly what they were coated with.
I also think that the ACL bearings are coated with something anyway, but cant rememeber for sure.
I got my complete bearing set for around £130 for the ACL's.
When I put a set of bearings into my 525tds not so long ago, the big end bearings had one shell was SA ( alu ) with the other shell LC ( Lead/Copper ). I had never really seen that before, and the bearings did come from BMW, not an aftermarket supplier.
re teflon coated bearings...
EJ20 Rebuild
[Edited by ustolemyname??stevieturbo - 1/11/2003 12:22:23 PM]
I also think that the ACL bearings are coated with something anyway, but cant rememeber for sure.
I got my complete bearing set for around £130 for the ACL's.
When I put a set of bearings into my 525tds not so long ago, the big end bearings had one shell was SA ( alu ) with the other shell LC ( Lead/Copper ). I had never really seen that before, and the bearings did come from BMW, not an aftermarket supplier.
re teflon coated bearings...
EJ20 Rebuild
[Edited by ustolemyname??stevieturbo - 1/11/2003 12:22:23 PM]
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