TT, so is Mk6 engine a significant improvement over E30 engine?
That is one of the $64,000 questions. Yes, it does have a number of improvements over the current 2.0TFSI engine (found in the current GTI and Ed30, to name just a few).
Some of the more important features.
The actual distance between the cylinders is now slightly larger - this allows for a larger volume of water in the coolant passages, and also allows for larger bore (which creates improved torque compared to smaller bores), and larger valves. All of this means that major improvements in engine efficiency - leading to lower CO2 emissions, and fewer visits to the V-Power pumps too. And for countries such as the UK which use emissions based taxations, this will then lead to lower tax bills.
The drive mechanism for the camshafts is also completely new, and is basically derrived from the V8 engine first used in the B6 S4. On the current GTI/Ed30 engine, it uses a rubber/kevlar timing belt. These timing belts are a "maintenance item", and on all models of the Mk5 platform (Golf V GTI/Ed30, Audi S3, Audi TT2, Å koda Octavia II vRS, and the Seat Leons), it is a real arse to change, because the right engine mount can not be fully removed - making access to the belt a royal pain in the arse. Think of the sidelamp bulbs in Golf V Xenons, and you should get the picture. On the new "Mk6" GTI engine, the rubber
band belt has been ditched in favour of a much slimmer timing chain. This is completely maintenance free (providing you change your oil regularly with quality VW approved brews), and because chains are about a third of the width of a timing belt, save space too.
Then there is the actual variable valve timing (VVT) - the current GTI can only use VVT for the inlet camshaft, whereas the new motor has VVT on both inlet and exhaust valves - again, leading to improvements in both power delivery and reduced emissions.
The final major change to the "innards" of the engine are the introduction of variable lift, or opening of the exhaust and inlet valves. Anybody who has an interest in the V-Tech technology will already be aware of this. However, being as this engine was initially developed by Audi, and this specific technology is penned as "valve-lift", it will be considerably more refined, and completely stepless. Basically, at low engine speeds (depending on how the system is set up - and I've not fully studied this yet), just one of the two inlet and exhaust valves will be opened (for improved torque, from better "swirling" of air-fuel in the combustion chamber), but at higher speeds, both valves will open (allowing for "freeer" breathing, hence more top-end power).
So, as a final "summary" - will it be "better" than the current engines? Well, for refinement, power delivery and economy - then a big yes. For out and out performance - don't know - proof of the pudding will be in the eating, and all that!
