Hi guys, this is my first post here so please go easy.

My 02 AUM Revo1 has done 160.000km in Greek roads, that means crap roads, really high temperatures and to top it up 150.000km were done with the stock side mount intercooler(it now has an EVO8 with a modified bumper). So after spending some money here and there about the car(ATP Mani, 100CPSI cat, 63.5mm exhaust, Samco TIP, 007 BOV etc etc) and after being torn whether I should go for a K04-023 Hybrid ~310hp solution or GT28RS~330-360hp, I thought I should better start by replacing the conrods and pistons first because I havent got the slightest idea what their condition is.

So my question is this: Has anyone opened the engine at 120.000 miles on a remaped car, if yes, what was the state of the cylinder head? I want to buy the conrods and the pistons but a friend of mine keeps telling me that my engine after driven hard for maaaaaany miles, it will most probably need some work done in terms of making the cylinders a bit wider and I would probably need to go for either 81.5mm or even 82mm pistons. Has anyone seen or heard something on this one?

I 've heard that the cylinders will have un-even surfaces and some kind of 'pockets' will have been created. If anyone has any kind of experience into that I would really appreciate it

Why do you want to replace te pistons and rings?just for the mileage?This is really silly.Make some serious test,like a compression test,leak test...etc

How the hell you gonna fit larger pistons?Who are making those larger pistons?You know....pistons are not perfectly round shape,they ar a bit oval when are cold,and are getting round after expansion at the operating temp.

This is a very long discussion....but overall,if the engine runs good,no strange sounds,and compression test is ok,you must forgot about rebuilding,even is is 500 000 km/miles

He wants to rebuild because he wants to run more power with a bigger turbo which needs to be done if you want to run more than around 300hp as the stock engine componants wont cope with the stress of that much power especially at higher mileage if its had a hard life

The reason I want to replace them is because the car was driven hard at temperatures exceeding 35C with practically no intercooler and there is no one to guarantee me the state of my pistons and whether they will be ok to use them with a GT28RS @350hp, even if the compression test is really good or even if the engine is opened.

The engine runs really smooth, I do not have to put extra oil at all between the changes. No funny sounds no knocks no leaks no irregularities in general etc etc. The way I thought about it is since I am changing the conrods - thats for sure - why not changing the pistons and then go to sleep at nights worry free.

So if I have it tested for compression and the compression is not good, what would that mean

leave it as is and install GT28RS is not an option

if your opening up your engine anyway puting new pistons etc in seems a good idea,no point puting rods in then your piston lets go half way up the road and f u a otherwise good engine.

I know, thats what I was thinking but I dont know whether the new pistons will have to be 81mm or my cylinder head will have some damage after driving it hard for so many miles under stupid temperatures. And I was hoping to find out whether someone has opened their tuned engine after 120k miles or something, and in what condition their engine was, just as a guide or reference and not to follow as a rule, obviously.

I had completely forgotten the compression test which I will do for sure and it is easy and low cost, however I will have to search around to find out what kind of numbers should I expect (if anyone knows for sure please let me know)

10-13 bar but more important that all cylinders are within 0.75 bar of each other.

No leaving as is and installing a big turbo is a no no.. As i said in my other post the stock internals probably wont cope with that sort of power you are wanting to achive from a bigger turbo you will need to use forged internals to cope with that power.. Are you not happy with how fast it is you can achive good enough performance and figures from the stock turbo

110mph to 155mph is really slow... thats another huge discussion

I had my old TDI custom remapped from 115bhp to 180bhp on 228k miles

I can say with reasonable certainty that standard rods on a 1.8t over 350 hp is not to be recommended. My son had a really heavily modded SEAT lcr that he bought already modded to 420hp from an alleged top line tuning firm. First decent full power run put a rod out of the block. Engine was built badly on standard rods. We rebuilt using integrated engineering rods, and a new block.

To be honest, at that level of hp, I would let an engine company rebore the block, and match forged pistons to the rebore. Also, I would fit aftermarket rods and have the crank and rods balanced as a unit with a lightened flywheel. You may need a head skim too, depends on its condition when you strip it.

Hope it helps

Phil