Oooops... It seems that my English not enough to understand what you mean
Do you have any pics?
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Oooops... It seems that my English not enough to understand what you mean
Do you have any pics?Oooops... It seems that my English not enough to understand what you mean
This isnt a clio specific image, but this is what I mean:
The bearing has at one got a tag that locates into a cutout, this helps to prevent it from turning.
Bearing crush should indeed hold them in place, but on the centre main bearing in particular on the clio, the slightest loss of oil pressure can see the crank "grab" it and force it to spin, when this happens it then means the hole in the bearing no longer lines up with the oil feed hole in the block, and then its game over.
Where as if the bearing is tagged, when the crank picks up on the bearing in times of low oil pressure it just does a tiny bit of wear to the front surface of the bearing, which is a much more preferable situation, yes its increased wear but it doesnt cause the same sort of dramatic failure that a spun bearing can.
Ultimately if you get low oil pressure a lot and the crank keeps picking up the bearing it will fail of course, but better if it takes a few dozen times than just once, lol.
I think I follow that, thanks.
I've never actually seen a centre main bearing, didn't know there was a hole lined up in them. Assumed they were the same as big end bearings. Got a pic for reference?
I ask this question because there are very good and reliable main bearings from ACL Racing and I prefer to use them in my projects. However they have such tags (as they are for F7R engine) and so they can not be installed to F4R without this additional cutting!
But big end bearings have a hole in them as well though?
The oil goes in through the drillings in crank via the holes in the main bearings, and then comes out the holes in the big end bearings in order to lubricate the big ends.
Its quite easy to just get the block/rods machined to accept the tags, we've just done it on the latest engine build for Porkie, I will get some pictures when we do the block for my turbo though as not got any of Lee's, unless steve happens to have some (he built this one not me as I was too busy), I can ask him but it seems unlikely as he sucks worse at taking pictures than I do, lol.
I'm getting my words muddled up completely then! No idea what bearings are what now lol!
I assisted* my mate whilst he changed some bearings on the bottom of his con rods, whilst fitting ARP rod bolts too. I thought these were big end bearings? They didn't have any holes in them, well not that I could see anyway....
Apologies if my terminology isn't perfect and I'm confusing people.
*By assisting I mean holding a flash light and passing things to him
See http://www.cliosport.net/forum/show...ith-a-clio-cup-race-car&p=9723495#post9723495 Porkie's post #930 shows the block machined for tags.
Steve
I'm getting my words muddled up completely then! No idea what bearings are what now lol!
I assisted* my mate whilst he changed some bearings on the bottom of his con rods, whilst fitting ARP rod bolts too. I thought these were big end bearings? They didn't have any holes in them, well not that I could see anyway....
Apologies if my terminology isn't perfect and I'm confusing people.
*By assisting I mean holding a flash light and passing things to him
Little end = where piston meets rod
Big end = where rod meets crank
Main = where crank meets block
Bigs and Mains have holes.
Yeah that's what I thought, thanks.
But I'm sure there were no holes in the big end bearings!!! :S In fact I'm almost certain, I even had them in my hand lol! Unless they are so small I wouldn't have seen without looking for them?
Apologies for going a bit off topic here.
I'd love to hear what you think the downside is other than some minor machining costs?
To me its a no brainer, its some extra insurance for very little money.
As fred says, its 2 half bearings, one with a hole and one without.
It can help prevent the shells turning as easily, so if you have a marginal loss of oil pressure it can help, if the crank really grabs the bearings though then it will just rip the tags off and spin anyway.
absolutely agree. tags will be gone in a second, the engine will have lasted about 3 revolutions longer
So a question about this manifold. should the 4 primaries enter the collector in a specific order in reference to the 1342 firing order. SHould it be done in such a way that they fire in a clockwise/anti clockwise circular way or diagonally each other, or next to each other e.t.c
Going to buy some plastic tubing to mock something up
Going to buy some plastic tubing to mock something up
Daz.
ClioSport Club Member
Clio 200 RS EDC
I would agree that if an engine has a problem with lubrication tagged bearings will not solve the problem, but it has been found that with other production engines used in competition which use untagged bearings in standard form, that when tagged bearings are used reliability increased, which is what i would want to do (I understand that not all engines are the same)
Ashford, MEM and Sodemo all tagged the bearings, although they did use steel cranks.
Steve
If that 3 revolutions is enough to be the difference between the bearing turning enough to starve off its own oil supply, then thats the difference between killing and engine or not.
Indeed, for such a small outlay, its a sensible way to marginally increase reliability.
Amazes me that anyone can build engines and NOT understand the benefit TBH!
Would love to see that discussion at Sodemo etc "Ive found a way we can save a few quid on each engine, by not tagging the bearings..."
Would go down like a turd sandwich.
Thats the sort of conversation that at a manufacturers where you are building millions of engines just to go shopping makes perfect sense, but for small volume production of high output engines, the same saving is not a good one.
but there should never be any contact between the bearing and the crank journal, always an oil film. if there's contact and it picks up enough to have spun un-tagged bearings, it's still going to score the crank so you're no better off.
The bearing is a lot softer than the crank, so if the reason its picked up is just a very short term lack of oil pressure (can spinning off a track for example) its perfectly possible for the untagged bearing to move slightly and the crank still be fine.
But now that the bearing has moved, it blocks the oil feed off, and its game over.
Going back to your manifold Laine..
Can you TIG weld?
Because TIG'd stainless (310 is a nice grade for very high temps, but the cheap and cheerful 304 should be ok) is the only way its worth doing.
Can you TIG weld?
Because TIG'd stainless (310 is a nice grade for very high temps, but the cheap and cheerful 304 should be ok) is the only way its worth doing.
No as above i was intending to mig weld the whole thing (to keep it simple), and have it ceramic coated afterwards. There are plenty of mild steel tubular manifolds out there?
I contemplated MIg welding a Stainless setup but means getting a bottle of trim mix, e.t.c which id probably never use again. Id obviously weld on a host of supporting brackets to keep the strain at a minimum.
I cant think of any turbo car (stnadard or modified) with a mild steel tubular manifold TBH.
The problem with loads of brackets, is unless they are just taking weight on a rosejoint that can move etc, you can end up causing problems where the thermal expansion of the manifold (cause its hotter) is more than the brackets,so the brackets then crack the welds by trying to hold the flanges in exactly the same place when the runners need them to move.
you would be FAR better off making all the pipework up, putting a small tack of MIG where needed to keep it all in place, then get it TIG'd up after.
I have tagged ACL bearings in this ConRod
What was the condition of the main bearings ?
if the main bearing spins blocking the oil gallery, tagged big end bearings will not help, as I stated.
Steve
172 cup, Impreza P1
Totally agree with Chip on this and this is what I did with my downpipe. I used a gasless MIG then got it TIG'd up by someone who knew what they were doing.
I actually always thought that tagged bearings were to make sure it was put on the correct way hence it it always offset to one side.
Cant see how a tag will stop it spinning.
OK comments taken on board about the welding, ill mock it, mig tac it in place, think i have a TIG bloke round the corner. Cheers guys.
Current engine is running well, but a bit of a dog at the same time, it stinks of oil when you boot it occasionally, but the catch tank doesnt seem to be filling up, but you get dribbles out of the breather filter (which is located near the scuttle, probably not helping the smeel into the cabin). It also blew out the rear cam seal blanking plug twice (crankcase pressure?), but i think that was because the piece of glue i put over the pin hole dot on the breather plate had come away? Engine makes some weird noise at 1900rpm too, something definately not quite right with the crank/bearings.
Nevermind cars coming off the road after next weekend, let the fun commence.
Current engine is running well, but a bit of a dog at the same time, it stinks of oil when you boot it occasionally, but the catch tank doesnt seem to be filling up, but you get dribbles out of the breather filter (which is located near the scuttle, probably not helping the smeel into the cabin). It also blew out the rear cam seal blanking plug twice (crankcase pressure?), but i think that was because the piece of glue i put over the pin hole dot on the breather plate had come away? Engine makes some weird noise at 1900rpm too, something definately not quite right with the crank/bearings.
Nevermind cars coming off the road after next weekend, let the fun commence.
Think i will just buy 3-4 Clio 172 manifolds and chop them apart, should easily have all the right bends and straights, and the collector on them is decent enough, we know they dont crack (hence the manifolds are so cheap!). Time to get out the angle grinder.
They are stainless right?
They are stainless right?
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Yeah they are stainless.
NorthloopCup
ClioSport Moderator
I've got a box full of 90 degree stainless bends with plenty of leg length on them if your interested?
I have tagged ACL bearings in this ConRod
Yeah i'm sure ACL's are the problem, don't rate them at all
