3B conrod bearing update?

[audiman]

Er sort of. He just paid for a set of arrow rods!!

[diesel des]

Thanks. Looks like the ABY has the stonger stuff then.

[Keeper of The Kitten]

Nobody has mentioned main bearings on the crank, or the crank? What about those bits, will they stand for a bit more bhp?!!

I suppose it would be a good idea to say what can stand up to what amount of punishment, the best order to get stuff, and which bits to get done at the same time?

__MDC__

[caterpillar]

the crank will stand the punch anyway,but sometimes they crossdrill the rodtapps. the org rods will NOT stand 90 hp eatch....rod nr 3 are the weakest point,it has the badest oilfeed.

[caterpillar]

may i lay the tlfnumber at the web,were they have cheep rods???? in sweden???

[Doug_RS2]

So have got any pics and prices for these cheap Swedish Rods? I have never heard of them before.

[caterpillar]

have no pics of them,but they are the right stuff yea. for the 144mm and 20xbolt ca 116 euro a peace.h-profil. same for 144 and 19xbolt. and 158mm and 23xbolt about 125 euro......the guy have taken out 1000hp at the volvo b230 engine.he has also ALU volvo copy b230 block,with can bee bored and stroked too 3,9liter!!!!! at 4 sylinders!!!

[dkw_dude]

How high boost level does the standard bearing take? My RS2'ed 3B is running 1,5 - 1,6 Bar, havent changed the bearings..

[audiman]

Main bearings are good for large HP. @DKW, i would change the big end bearings if I were you just to be sure. If the go wrong then it could damage the crank. The only time you need to worry is with anything over 24psi. This is when stock rods will bend.And if the rod will bend then the bearings are under a lot of stress.

[Keeper of The Kitten]

Nice one Tom, looks like I've sussed out what I want now!

__MDC__

[auditude]

replacing rod bearings in-situ

Hi,

Okay, so I just ordered an OEM metal head gasket and new rod bearings. Is there anything special I should know or do to replace them with the motor in place? This is for my 200q20v which will then get an RS2 EM and turbo.

I'm wondering specifically about the rod bolts. I just undo the caps, swap out the bearings, and reassemble with the old nuts and such? What about assembly lube and torquing them down? I was reading about (race) rods and there was stuff about measuring the bolt stretch of an assembled rod to determine exactly when they were properly torqued. Is anything like that required, and is the old hardware okay to reuse like that?

Thanks,

Ken

[audiman]

On the stock rods you do dont need to measure stretch. You dont need to replace anything except the bearings, maybe an ideal time to replace piston rings if its high mileage???? as the head is off

[porkkis]

3B big end bearings were weaker! At some point the weaker ones were dropped and only the RS2 ones are listed to all 20vt 5cyl engines.

[Keeper of The Kitten]

Absolutely right Porkkis - it's the reason I started the thread, to find out exactly that!!!

__MDC__

[auditude]

On the stock rods you do dont need to measure stretch. You dont need to replace anything except the bearings, maybe an ideal time to replace piston rings if its high mileage???? as the head is off

Yes, that's a real decision I need to make. The car does have 170k on it. It doesn't seem to consume oil, but I have seen a puff of smoke on startup on two occasions. Is it worthwhile to replace the rings without reconditioning the cylinder walls? Is it even perhaps a bad idea to not do anything to the bores when replacing rings because the ridge might not fit with the new rings?

I'm starting to convince myself that what I really should do is basically rebuild my other 3B motor and swap it into my 200. Then my 200 motor will get the "big rebuild" with new rods and such for the header and GT30R, and go into my project Type 85. But that's more downtime for the 200, which is my only car with working a/c right now.

If I could get away with replacing the rings, rod bearings, and head gasket, without pulling the motor, that would be nice. The ring job seems a bit more technical to me since they need to be trimmed to fit into the bores, as far as I know, while the other stuff is just remove and replace.