Is this correct?

[newbie77]

Hey guys,

I just read this over on Dubforce.net:

RS2 and S2 conrods are the same.
The RS2 pistons are forged Karl schmit pistons where as the S2 ones are cast and not as strong.

Is this true? I keep coming across different answers to this and I'm getting really confused. Can anyone set my mind at ease please?

If it is correct, will S2 pistons and rods withstand 350bhp+?

Thanks!

[Sonic]

Not sure on the exact technical front, but i thought ABY and RS2 were the same.

Its not so much the bhp that will kill the rods though, but the torque.

There are plenty of 350bhp ABY/RS2 examples, and i understand the pistons dont become a problem until you are running stupid power.

[Jamo]

Rods and Pistons are the same in S2 ABY and RS2

The 3B had stronger rods than both ABY and ADU apparently.

Pistons aren't a problem for any bhp but compression ratio is, you'll have to fit a compression reducing gasket to around 8.5 CR for safe 450-500 bhp range.

Bhp isn't your issue it's torque, stock setup will laugh in the face of 350 bhp, however if you throw big torque at the rods they will bend.

[GazzaG60]

personally i reckon that all the rods from kr 16v to aby at 144mm are the same. they all seem to have a very similar per cylinder strength.

torque is the main issue but bhp (ie revs) will hurt them too. especially the standard bolts.

on 16v engines the cheapest option is to use ARP ford 289 bolts. skim the bolt head with a hand grinder and press um in. that makes them hold the rpm. same will work for us id expect. i got a spare set of 289's ill see if they fit the i5 rod. you got 2 sets of arp 289 (ford v8/2=vw 4 pot) for the price of a single set of arp vw.

i got kr,9a,6a and aby rods in the store if you want me to check.

[Rusty]

Yes, they are the same. Pistons can take 600 ponies as proved by Audiman Tom, rods are safe to about 400 ftlbs and will do over 400 ponies but there's little headroom. There aren't many differences ABY to ADU in the engines.

[Jamo]

http://www.s2forum.com/forum/showpost.php?p=28084&postcount=14

But then we had this again http://www.s2forum.com/forum/showthread.php?t=22355

[GazzaG60]

i dont think its worth putting figures on things. each rod has had a different life. some will have had the stresses worked out better over time, some not.

im still not hitting those figures and as a definitive cannot be put on these things its better to save a block and spend a few hundred on rods and bearings.

there may be more materiel there but that doesn't make them necessarily stronger. maybe just a different tooling in a differnet factory.

[Jamo]

I aint argueing with Mihnea to be honest, he's seen more and mapped more than most

[GazzaG60]

its not an arguement. think all respect his experience but more meat doesn't mean more strength necessarily.

at the end of the day all vw rods are crap for high hp.

[urS6Tom]

does anyone know whether AAN uses the same rods and pistons as 3B, ABY, ADU?

[GazzaG60]

id expect so. no point making different ones when they have been the same for best part of 20 years

my take on it so far is 220mm deck =144mm, 236mm=159mm. hope i got that right.

longer rod make sfor better rod ratio and longer time at TDC, less lips on the cylinder wall on one side

[newbie77]

wow!! Thanks for all the replies guys, good to know there is some much usefull knowledge out there! :-)

Thanks a lot :-)

[UrS4boy]

does anyone know whether AAN uses the same rods and pistons as 3B, ABY, ADU?

Yes.

The rods are PN 027 198 401C and they are common to the 7A, KV, NG, NM, 3B, RR, AAN, ABY and ADU.

The pistons PN 034 107 065M are a exclusive to the 20vt including the 3B, RR, AAN, ABY and ADU.

On a vaguely related note, I discovered today that there are no part numbers for crank bearing caps or bolts. The caps are line bored to a specific engine block (hence no replacement parts) and the bolts are reuseable (65 Nm).

[Jamo]

Yes.

The rods are PN 027 198 401C and they are common to the 7A, KV, NG, NM, 3B, RR, AAN, ABY and ADU.

The pistons PN 034 107 065M are a exclusive to the 20vt including the 3B, RR, AAN, ABY and ADU.

On a vaguely related note, I discovered today that there are no part numbers for crank bearing caps or bolts. The caps are line bored to a specific engine block (hence no replacement parts) and the bolts are reuseable (65 Nm).

Yep same applies to the cam caps as well as they are also inline bored