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you're good at spending other peoples money.......I'm good at over thinking stuff!
I guess I was looking at the older generation engines (they went into production in 96' I think), pre-variable valve timing/lift and all that jazz which varies dynamic compression doesnt it and definitely pre DI engines. Perhaps I was going back too far.
Well if I do go 9+:1 there are plenty of options. After doing a bit of reading it seems that while VAG quoted 9.5:1 for the K03 cars and 9:1 for the K04 cars, the actual compression when cc'd puts them both at closer to 9.25:1, so its possible they are more or less the same comp anyway.
Yeah maybe I will get MIA to have another look at the pistons. He didn't like any of the rings though. I remember him saying it was one of the tiniest little oil control rings he'd seen and that it looked like the 2nd compression ring gets used as a double duty oil control ring too which is why he said ditch them for something that'll last. Interestingly when we compression tested it a while back trying to pin down oil consumption, the comp test and leak down test came back sweet and my mechanic/tuner buddy next door to them did ask if these engines are known for doing oil control rings. But like you said if they can be cheaply modded to accept more stout rings then that may be worth exploring, cos there's no point looking at shiny new pistons if I don't have the dollars left over to complete the build. I think I did read somewhere that the stock pistons are a forged Mahle made out of that more brittle 4032 I think so hopefully they are not too brittle to be machinable. As I said above the other option is to use my spare engines pistons if they are in better condition but that'll need 900 bucks worth of 19mm pin end rods (only one brand from the US does them) - still cheaper than pistons though. So i'll suss out salvaging the S3 pistons first, failing that look at using the Polo pistons next, and failing that I'll have to go with aftermarket pistons.
I'm going to do one more measure session of the MK6 gti turbo mounted on the spare engine and double double check that it wont fit against the steering rack before I turf that idea because it really does have a lovely manifold compared to the K0x ones and really is like lego the way it all integrates with the stock pipework routes, intercooler, intake and exhaust etc. Not bolt n' play like a K03 hybrid but the next easiest option I think.....provided it fits against the firewall.
I guess I was looking at the older generation engines (they went into production in 96' I think), pre-variable valve timing/lift and all that jazz which varies dynamic compression doesnt it and definitely pre DI engines. Perhaps I was going back too far.
Well if I do go 9+:1 there are plenty of options. After doing a bit of reading it seems that while VAG quoted 9.5:1 for the K03 cars and 9:1 for the K04 cars, the actual compression when cc'd puts them both at closer to 9.25:1, so its possible they are more or less the same comp anyway.
Yeah maybe I will get MIA to have another look at the pistons. He didn't like any of the rings though. I remember him saying it was one of the tiniest little oil control rings he'd seen and that it looked like the 2nd compression ring gets used as a double duty oil control ring too which is why he said ditch them for something that'll last. Interestingly when we compression tested it a while back trying to pin down oil consumption, the comp test and leak down test came back sweet and my mechanic/tuner buddy next door to them did ask if these engines are known for doing oil control rings. But like you said if they can be cheaply modded to accept more stout rings then that may be worth exploring, cos there's no point looking at shiny new pistons if I don't have the dollars left over to complete the build. I think I did read somewhere that the stock pistons are a forged Mahle made out of that more brittle 4032 I think so hopefully they are not too brittle to be machinable. As I said above the other option is to use my spare engines pistons if they are in better condition but that'll need 900 bucks worth of 19mm pin end rods (only one brand from the US does them) - still cheaper than pistons though. So i'll suss out salvaging the S3 pistons first, failing that look at using the Polo pistons next, and failing that I'll have to go with aftermarket pistons.
I'm going to do one more measure session of the MK6 gti turbo mounted on the spare engine and double double check that it wont fit against the steering rack before I turf that idea because it really does have a lovely manifold compared to the K0x ones and really is like lego the way it all integrates with the stock pipework routes, intercooler, intake and exhaust etc. Not bolt n' play like a K03 hybrid but the next easiest option I think.....provided it fits against the firewall.
it's definitely time to look at more common engines with the same major dimensions, bore, pin to deck height and pin diameter. As in the post above Honda B series pistons are 81 mm, cheap as, very common from multiple piston manufacturers with turbo options. I'd start there and stop paying the "VW tax" (applied just because they aren't as common). 
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