JonnyC's Audi S3 Project..

[tony_danza]

Am I the only one thinking the engine would be much funnier in that red Rallye in the background?

Will you be inserting that piston into any particular place, Jonny?? I have a feeling I know where it deserves to be...

[jabbalad]

Damaged piston.. (Not for the faint hearted!!)




Strange thing is that the crown of the piston is ok, this leads me to believe that it was more a lack of oil / sh*tty oil problem rather than pre ignition as surely there would be damage to the crown if this was the case?

That does look a lot like damage from detonation (most probably crap fuel) Detonation will usually be shown on sharp edges, so usually goes down to the rings and starts eating away there... as its done in your pics.
i would struggle to see how bad oil could do something like that.

Good to hear its on the road to repair tho

[jonnyc]

Perhaps some sort of Top Dash Mount , on the lines of something like the Ford ST/RS?

Got some ideas, just dont want it to look like a chavvy jap car!

Am I the only one thinking the engine would be much funnier in that red Rallye in the background?

Will you be inserting that piston into any particular place, Jonny?? I have a feeling I know where it deserves to be...

Thats having a 1.8T conversion as far as I know with a GT30 turbo, so its going to be pretty quick!

Lol, no comment..

[Phil Mcavity]

If the top of the Piston crown was detonated, i would agree, but the top of the piston that ive read says its fine, so wouldnt really point to crap fuel. Lack of Lube maywell have caused it, BUT if thats the case, why arent  cylinders 2,3,4 like that??.If the other cylinder are showing signs then id be looking at potential bad fuels, but im not so sure imo.

Engine overheat from lack of cooling is possible,(and looks like it from the photo's tbh) cylinder furthest from the water pump would be 1st to cop it from my experiance. Poor Lub would again show(or signs of) on all cylinders not just one.

Again, the damage shown is only minor!, compared to major engine failure which that isnt no way near that stage.

What condition are the Piston and Oil scraper rings like Jonny on the other Pistons?. Signs of jamming or carbon burn past the lowest compression ring?

[Hurdy]

Ideally I wanted Oil pressue, Oil temp, Boost and AFR but there is no nice way to mount them in an S3, im going to have to come up with something though..

There are digital readouts that will do all those measurements. Just needs to be done right. 

[jonnyc]

If the top of the Piston crown was detonated, i would agree, but the top of the piston that ive read says its fine, so wouldnt really point to crap fuel. Lack of Lube maywell have caused it, BUT if thats the case, why arent  cylinders 2,3,4 like that??.If the other cylinder are showing signs then id be looking at potential bad fuels, but im not so sure imo.

Engine overheat from lack of cooling is possible,(and looks like it from the photo's tbh) cylinder furthest from the water pump would be 1st to cop it from my experiance. Poor Lub would again show(or signs of) on all cylinders not just one.

Again, the damage shown is only minor!, compared to major engine failure which that isnt no way near that stage.

What condition are the Piston and Oil scraper rings like Jonny on the other Pistons?. Signs of jamming or carbon burn past the lowest compression ring?

All the other pistons look mint to be honest.. Didnt have a really close look, but enough to notice that they all seemed ok..

[jonnyc]

Ideally I wanted Oil pressue, Oil temp, Boost and AFR but there is no nice way to mount them in an S3, im going to have to come up with something though..

There are digital readouts that will do all those measurements. Just needs to be done right. 

Lol I know what your thinking.. Not a bad idea actually 

[Oli]

Strange thing is that the crown of the piston is ok, this leads me to believe that it was more a lack of oil / sh*tty oil problem rather than pre ignition as surely there would be damage to the crown if this was the case?

Head off..

That is an amzing amount of damage to the piston, not to have damaged the cylinder more.

And also what are your plans for the chassis/wooly steering ?- That was one of my biggest complaints with my S3.

Good luck with the build, looking and sounding great already.

[jonnyc]

That is an amzing amount of damage to the piston, not to have damaged the cylinder more.

And also what are your plans for the chassis/wooly steering ?- That was one of my biggest complaints with my S3.

Good luck with the build, looking and sounding great already.

I know, I was shocked.. But its a good thing for me!!

Well the whole of the rear end is mounted to the chassis on 4 big soft mounts, when I say soft I mean very soft! Im having the mounts send away and there going to be re produced in CNC alloy.. That should tighten things up a little! Then the whole car will be polybushed, the problem seems to be that everything is mounted so softly.. Something that the Golf doesn't have as the rear end is different..

Seems there is a hold up with the turbo, was meant to be sent last Friday and now I have been told there 'hoping' to send it Thursday.. So theres another week delay! Arrrgh..

[john_o]

OMFG , I cannot believe that hasnt taken the whole block with it ! you must have only just caught it ....
given the revolutions the pistons do , thats not been up and down too many times once its started to fail.
maybe it was a weak spot or manufacturer casting error ? esp with a chunk out after  the last ring that has sharp not rounded edges.

in terms of it being cylinder 1 , anything special about that one? (I assume its the same firing order etc like the golf , and cyl3 is still the longest inlet tract? as thats where the expected detonation would happen first/worst)

I always held off on the catch can thing but you are confirming my worst fears 

great build jonny 

[gillm]

you thought about getting the head ported ? i just got my head back from the man in the head , ala dave crissil and its mint . .

[Smiler]

First off Jonny love your build threads and keep up the good work  
A user on the R32oc website posted info about a VAG Fuel Additive
Working for Audi I get to see things that Joe Public obviously doesn't. On an RS4 TPI (Technical Product Improvement) I noticed that they recommended an OEM Fuel Additive as in there words naturally aspirated engines suffer more from coke buildup in the inlet manifold; affecting performance and emissions. The fuel additive which can be used in any VAG Petrol engine; Part No. G00170003. Think of it as a internal engine cleaner. It currently has an RRP of around £7.50 including VAT and is 1000ml in size. The official recommendation is 10ml to every 10 litres of fuel but I've (unwittingly) pushed it to 80ml to a 60litre tank with no issues. for any TFSi owners reading etc. This stuff is suitable for any petrol engine

Being curious I've been thought i'd try it over a few weeks and towards the end of the first tank I noticed an increase in throttle pick-up and around 1-3mpg improvement in general driving. Since then I've been using 1 in every 3 tankfulls and after 3 months I'd obviously highly recommend it to you Guys on here. Even if you are using 99RON petrol (which I do) you WILL notice a difference. Especially if your car is higher mileage.
http://www.r32oc.com/general-chat/13417-vag-fuel-additive.html

[Phil Mcavity]

smiler, is this stuff simular to Redex or is that a different Spec?

I bought some but have tried it once, prior to a rolling road day  , but wasnt sure it would aid carbon build up on the inlet side of things?. Is it best to Bin the stuff and get what you reccommend?

Cheers

[Smiler]

smiler, is this stuff simular to Redex or is that a different Spec?

I bought some but have tried it once, prior to a rolling road day  , but wasnt sure it would aid carbon build up on the inlet side of things?. Is it best to Bin the stuff and get what you reccommend?

Cheers

Phil cant comment if its better than redex ,i have just copied and pasted from the other forum.
BTW i paid £6.90 inc vat

[Phil Mcavity]

Cheers Smiler, just been reading that thread and its been said its the same stuff a s Redex. So perhaps my moment of madness may be helpfull after all