1.4 vs 1.5 tfsi - what's the difference?

audigex

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I understand the 1.5 is apparently based on the 1.4, but although the displacement is larger, the two seem to be... basically identical. Both have (with the S-Tronic gearbox) a 0-60 time of ~8.2 seconds, as far as I can see, comparable top speed etc.

Unless I'm missing something about the torque or economy, they look identical. What am I missing?
 
My S Line, scheduled to be built Next Week! will have the new 1.5. Im interested to just how good the fuel efficiency is. I dont expect to get anything like the figures claimed by VW. I have a 2.0tdi at the moment so I keen to see if the low down torque is as good as claimed.
 
@Chris43, this is what's confusing me - my car is scheduled for delivery in September, but it only seems possible to order the 1.5 right now, mine was ordered at the very end of March (no idea what the delay is) - so I'm not actually certain which I'll get, since it's a fleet car.

I'm not really too bothered either way, as it sounds like the difference is at best a tiny bit of in-gear acceleration (but the same 0-60?) and responsiveness. Thanks guys
 
Update.

I managed to track my order on the Audi website on Saturday and its now showing Week33 build or mid August in simple terms. Its a bit of a kick in the **** after Bolton Audi stated it would be built this week but part of me felt that date was too good to be true anyway.

@audigex, your delay could be down to a number of things. There doesn't appear any obvious logic to the order cars are built but im sure there is. Most likely its engine / gearbox availability / major component availability. They may group together all 3 door, 5 door LH drive, RH drive etc.

One thing that is certain, assuming your car isnt built yet you'll definitely get the 1.5. This week, the new manufacturing year starts (MY18) and all cars ordered with a 1.4 will get the 1.5. VAG will have stopped production of the 1.4 all together
 
Interesting on the last point - I'm not ordering directly so it may be that my company are aware but nobody has informed me: my order still states 1.4. I assume you're right, because it seems odd that they'd keep a 1.4 sat around until September just for me

The rest of the delay is rather expected tbh - my last Audi had a 9 month lead time, admittedly with the Japanese tsnunami making a mess of their supply chain. I'm not too worried about the delay, just curious about this engine.

I think the end result is that it just appears to be a minor refinement of the 1.4, and that the fact it's a 1.5 instead is almost semantics.
 
http://www.carscoops.com/2016/04/vws-next-gen-15l-tsi-engine-detailed.html

"introduction of a turbocharger with variable turbine geometry, a feature only seen in petrol engines of much more expensive machinery, like Porsche’s latest 718 series and the 911 Turbo."

"The compression ratio is now a rather impressively high 12.5:1, with the engine working under the Miller combustion cycle. The cylinder liners in the aluminium crankcase for the 148hp version are coated using a procedure called the atmospheric plasma spray (APS) which reduces friction on the piston rings and increases the heat dissipation when compared to cast-iron crankcases."

Hopefully won't suffer from oil consumption issues with it's new fangled low friction piston rings not bedding in. The petrol engine is turning into a diesel though with variable vane turbo's that diesels have had for 15 years or more and 12.5 to 1 compression ratios. Also high torque levels at low RPM.
 
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The last post in this thread was more than one year ago. Since then, is there anyone who tried both 1.4 TFSI and 1.5 TFSI on this forum? Could you notice any difference?

This is an important question to me as I'm choosing a FL 8V. I was looking at 2018 1.5 TFSI Sport S-tronic Saloons for a while. Almost all of them are poverty spec A3s except one that is, despite having the same price, one year older (July of 2017), has more km on the clock, but it also has a nice specs package (approx. £6000 equivalent in the UK.) But it's the 1.4 TFSI and I'm unsure what should I choose: the lower specs with 1.5 or the higher one with 1.4.
 
Go for the higher spec 1.4, then you are getting the best of both worlds. The 1.4 is a sweet, refined and more than quick enough. If you are thinking the 1.5 might be better then think again as it isn't..
 
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Go for the higher spec 1.4, then you are getting the best of both worlds. The 1.4 is a sweet, refined and more than quick enough. If you are thinking the 1.5 might be better then think again as it isn't..
Thanks! I just read something similar at Briskoda. The 1.4 has one more benefit in Denmark: the vehicle tax on 1.4 is a half of the one on the 1.5.
 
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Go for the higher spec 1.4, then you are getting the best of both worlds. The 1.4 is a sweet, refined and more than quick enough. If you are thinking the 1.5 might be better then think again as it isn't..

I agree - I’m 100% happy with my 1.4T COD - outperforms the 1.8T Mark 4 Golf GTI it replaced and delivers nearly 50mpg (not both of those at same time!) . Having said that I would be interested in knowing if the 1.5T COD is noticeably better for anything


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