Conrods !

[nobananas]

Right, I am just in the process of tearing down the bottom end of the lump I got from Siamblue last week and have noticed that the conrods from my old engine which I am intending to use are slightly different from the ones in the new engine (apart from the newer ones being slightly more curved then normal !) The newer lump is an S70 B5234T3 and the conrods from it appear slightly wider in the beam and a little different around the little end. The gudgeon pins also seems to have a larger inner bore then the 850 ones. Is all this purely different design characteristics or is there a significant difference in strength between the old 850 rods and the newer s70 ones which might result in me sourcing some replacements ?

[nobananas]

Also just noticed, am I right in thinking that mahle pistons are non-original ? As that appears to be whats fitted in my old 850 lump !

[pzorb]

I think the 850R and S/V70s had stronger internals than the older 850s, but not by much.

[nobananas]

Thanks pzorb. Anyone else add anything to this ? Should I replace the rods ?

[Redbrick]

Would it help if I posted a piccie of one of the bent rods that came out of my 850R engine B523T4?

The Volvo specialist that rebuilt it found that the standard T5 rods were identical to these rods- same part number.

Mahle pistons don't sound original, ask US Doug or Spesh if he's still about.

[nobananas]

Thanks redbrick. It might be helpfull if you could post a piccy of one of your 850R rods just for comparison.

[Redbrick]

http://i4.photobucket.com/albums/y132/apurnell1970/Volvo/2006_10290016.jpg

And a side view.... kinky ;)
http://i4.photobucket.com/albums/y132/apurnell1970/Volvo/2006_10290033.jpg

Just to justify why a new BCS should be in the stage 0 tune up, before you start playing!

[nobananas]

Thanks redbrick. That looks identical to the rods from my 850 block (except mine are straight !) The s70 rods are round where they pass around the little end rather then 'cut' at 45 degees. Some of the s70 rods were worse then that to the extent that some of the little ends had a little nibble on the balance weights on the crank ! (bet that woke you up when it happened Gary !)

[siamblue]

You can post them up NB if you want i was meaning too, some are double s shaped, expensive mistake on my part, even though some people will say otherwise,

[nobananas]

Here's Sb's effort at conrod modifying !

[powernut]

Lol Bloody Hell Dose He Wear Con Tacts Lol, (are These Std 850 Rods No Wounder They Bend Easy ,have You Any Pics Of The Others? Matey (what Causes This Over Boosting Or Something?

[BlackBeast]

Here's Sb's effort at conrod modifying !

Why did i laugh the first time i saw that pic!?!

[pzorb]

Wow they *all* bent. You should totally put them on eBay :saythat:

[siamblue]

Bloody expensive mistake on my part, but i have a nice R now from the proceeds of breaking my S70 :),

[BlackBeast]

You should totally put them on eBay :saythat:

Id hang them up on the wall of my garage to remind me every time i went in there what could happen if I was really unlucky with my BCS failing.

Note: I do not have a garage :( And yes, if a BCS does fail then that will be the result :( and thats why some people recommend fitting an EBC inline.

[mazza]

does anyone know how much a new BCS is?was thinking of changing mine as precuation..

[nobananas]

Lol Bloody Hell Dose He Wear Con Tacts Lol, (are These Std 850 Rods No Wounder They Bend Easy ,have You Any Pics Of The Others? Matey (what Causes This Over Boosting Or Something?

Yes this is caused by overboosting which is why we are worried about you're veedub boosting so high ! Be a shame to break it before you've had a chance to play !

[Redbrick]

does anyone know how much a new BCS is?was thinking of changing mine as precuation..

From memory about £60 or £70....

Beats £2500 for an engine rebuild....

Gary; RESPECT for your ability to bend five rods :worship:

[elliot]

Mahale pistons are std.I brought the later design BCS from the newer cars to control the boost better and it was around £35 from volvo.

[BlackBeast]

I bought the later design BCS from the newer cars

So was that from a P2 R or what? Bit more detail?

[Transient]

Mahle pistons and rods are standard equipment on the B5234t. The mahle sizes are as follows Std (81mm) +.20mm and +.40mm sizes.

[nobananas]

Cheers trans, that explains why the s70 lump i'm rebuilding has Volvo pistons whereas my 850 lump has Mahle.

[Transient]

Get some forged venolia or JE pistons with Corrillo rods mate. makes a huge difference!!!!

[nobananas]

I'll bet it does ! Unfortunately I need the money to spend on more frivolous things....like eating !

[Transient]

Ah yes well there is always that. I have a nasty habbit of just doing it and regretting buying toys later