1.8T 20V Con Rod Failures

[s3dave]

if the s3 had tits we would all be ******.....

 

[Welly]

if the s3 had tits we would all be ******.....

I'd love mine more.... and then I could do away with the woman. All points good IMO.

 

[badger5]

People need to stop thinking there engines are going to fall apart any minute lol. Ye rods fall but its a very small minority that do and they tend to be running quite a bit more torque and power than the standard engine spec.

Im doing a con rod FEA assignment in uni now and wanted to do it on a S3 rod but havent got the dimensions on one to measure accurately.

Nathan

fea assuming what fatigue stress?
life of these is old these days... old cars

 

[voorhees]

No, not dangerous. However, REVO maps are known for their aggressive delivery by all. Much less progressive than other maps, and that's due to the torque production. As Jo said, early and harsh torque isn't the best for the rods.

Many people are using, and have used, REVO maps for a long time with no issues. But out of the generic maps available, I would say they are the most likely to cause issues. That's not to say will.

Alex I thought you was going to state something definitive then lol

 

[badger5]

some points to consider.. based on my own experience and some very good engine builder advise given tome.

cylinder pressures are large... mine would have been >3000psi on ign timing I ran
get your calculators out and see what forces that introduces, and think a 4 degree ign advance added 400psi more
cyclic at your rpms, up and down..... I have posted the numbers on here before somewhere..

{why is this forum so slow when i type this is sits several secs before the words appear?? very annoying!)

 

[Welly]

some points to consider.. based on my own experience and some very good engine builder advise given tome.

cylinder pressures are large... mine would have been >3000psi on ign timing I ran
get your calculators out and see what forces that introduces, and think a 4 degree ign advance added 400psi more
cyclic at your rpms, up and down..... I have posted the numbers on here before somewhere..

{why is this forum so slow when i type this is sits several secs before the words appear?? very annoying!)

Oh indeed you did..... and with a wave of my magic wand.....

Likely det and boost combination caused the muchos cylinder pressure to bend the rod..
think in terms of >2500psi cylinder pressure during combustion to put it into prespective, 7.9sqin area, x 2500 = 19901 lb force = 9046Kg of downward force..........vs the ickle Rod

 

[Syvo]

i am looking at getting stage 2 revo map or custom map from wayne at chip wizards along with fitting full exhaust system and 4 bar fuel regulator would be looking at around 240bhp on my audi a3 1.8t quattro.

would ppl recomend rods or still be ok on standard rods as had a look at the engine in terms of taking it out seems a real pain in the ***

 

[Welly]

i am looking at getting stage 2 revo map or custom map from wayne at chip wizards along with fitting full exhaust system and 4 bar fuel regulator would be looking at around 240bhp on my audi a3 1.8t quattro.

would ppl recomend rods or still be ok on standard rods as had a look at the engine in terms of taking it out seems a real pain in the ***

To be fair, 240 is quite optimistic for those mods but that's another story. At that sort of mark you should be OK really, as long as the engine has 20mm wrist pin rods.

 

[Alex C]

what's the wrist pin size for the rods in an AMK engined S3?

 

[Sandip]

20mm

 

[Syvo]

if i give some one me engine code would they be able find out think its apy but will have to double check

 

[s3dave]

It is stamped on the top of the engine left hand side next to the top cam cover...

 

[DaveA3]

hmm question, what will my AGU a3 have? and are they the same as the s3? meaning i should be ok for 210ish bhp?

 

[Welly]

AGU has 20mm rods. I have an AGU block in my car, so I'm sure the block will be fine.

20mm rods will be fine for 210 - that's standard S3 power.

 

[DaveA3]

excellente i thought i read it somewhere. thanks for reassuring me so can relax a little now

why the **** didnt they make them stronger for s3's than the 150?

 

[Welly]

excellente i thought i read it somewhere. thanks for reassuring me so can relax a little now

why the **** didnt they make them stronger for s3's than the 150?

Because VAG are lazy quite frankly. All the same parts from the same parts bin.

 

[DaveA3]

yeh seems like alot of thought went into the first model then they couldnt be ***** to improve from there. probably the reason why it werent mapped further than 210/225 from standard! because they knew they took shortcuts on the rods

 

[badger5]

for the design spec of 225bhp they were adequate

later models get 19mm rods, and newest got sintered 19mm rods - EAK!

 

[aragorn]

As i pointed out previously, these rods are largely unchanged from the very earliest 058 blocks.

Bill, did you get a chance to compare a 16v Golf rod with an S3 one?

 

[DaveA3]

for the design spec of 225bhp they were adequate

later models get 19mm rods, and newest got sintered 19mm rods - EAK!

sintered as in made from a compressed compound? wah thats crazy

 

[badger5]

As i pointed out previously, these rods are largely unchanged from the very earliest 058 blocks.

Bill, did you get a chance to compare a 16v Golf rod with an S3 one?

no I dont have time
my 16v rods are inside my 16v engines

 

[badger5]

sintered as in made from a compressed compound? wah thats crazy

yep, aka snap rods

rods for accountants not engineers

 

[aragorn]

Ah k, tuffty thaught you might have had a set kicking around.

I wouldnt say the sintered rods are not for engineers, its the advances in modern engineering that allow those rods to be made like that, saving money and quite likely weight too, yet being strong enough that they will last in the standard application.

You cant really bemoan audi for fitting a rod thats only just strong enough for the engine it has built, if anything thats good engineering practice and tbh its pretty common across all manufacturers these days.

 

[badger5]

I can moan and I will
They did'nt used to, they built to a quality... no different to the other manufacturers when they go sintered route

Its engineered down to a price not up to a spec... and the spec such that it is is less than it used to be... which is backwards step to me, but the way of the world and bean counters influencing engineers.
All good for aftermarket of course, putting right OE deficiencies when upping the power game.

 

[Essflee]

Went to see how my car was getting on yesterday, new engine was just about in the car with lots of wires and pipes hanging everywhere

Mechanic did show me the old lump, he was one side of it and I was the other, putting a torch up to the engine it became apparent that there was 2 holes in the engine, look through one side and out the other, could see the piston hanging the wrong way up

Looked like a bullet had gone straight through the engine .

 

[Syvo]

my engine code is ARY would that have 20mm rods or 19mm

 

[Sandip]

19mm Paul, has Wayne told you he'll get 240bhp out of your A3?