4a-gze's Suck!

[ancullen]

I bought the latest issue of Wheels yesterday (December issue with 'Godzilla' on the front). On page 112 they do a short article on the new VW Golf GT (not GTi, just GT). It will sit between the 2.0L 110kW FSi Sportline and 2.0L turbo 147kW GTi in the Golf model line up. So you'd assume it will have a low boost version of the 2.0L turbo engine, like Audi use, wouldn't you. You'd be wrong.

 

The new Golf GT uses the new TSI motor, which is a 1.4L supercharged and turbocharged 125kW four cylinder petrol engine. VW call it the Twincharger (or TSI), and it's basically the same setup HKS used on their Twincharger setup for the 4A-GZE. Except it actually works properly and there should be more than about 30 examples built.

 

So why does the 4A-GZE suck? Well, the technical specs on the 1.4L TSI motor are EXTREMELY interesting. It has 10.0:1 compression, which is straight away obvious as being higher than that of the 4A-GZE. So you're probably all thinking that it runs lower boost. WRONG!!!

 

This is the part that blows my mind! The supercharger is a belt-driven Roots-type supercharger, just like the SC12 was. It also has a clutch mechanism so it can be turned on and off by the engine's ECU, same as the SC12/4A-GZE. However, the VW engine spins the supercharger at FIVE times engine speed. The 4A-GZE only ever ran the SC to 1.25 times engine speed from the factory, and up to 1.46 times engine speed with aftermarket pulleys. However, the SC on the VW engine only has to work at up to 3500rpm, where the clutch in the water-pump pulley deactivates it. The SC still spins at up to 17,500rpm, which is far more than the 12,000 available from the SC12.

 

It pumps up to 1.8bar, or 26.5psi through the engine!!! That's right, 26.5psi on a 10.0:1 compression engine!!! Now I'm sure you're all agreeing that this motor simply f@$king rocks! You're still underestimating it! From 3,500rpm onwards, the turbo takes over boosting duties. It is already spooled up thanks to the 3,500rpm onboard, and reaches maximum boost of 2.5bar, or just over 36psi! THAT'S FREAKIN' INSANE!!!

 

The 1.4L TSI makes 125kW and 240Nm of torque, which isn't that impressive after reading the above. However, the maximum torque is available from 1,500rpm all the way through to 4,750rpm. Maximum power is reached at 6,000rpm, but the redline on the engine is 7,000rpm and the cutout comes in at 7,500rpm. Again I repeat: THIS ENGINE ROCKS!!! What's more, VW are claiming fuel consumption of just 7.2L/100km, which again is just freakin' awesome. That's better than the 2.0L FSI Golf, and is meant to compete with diesel engines.

 

The Golf GT is meant to be released in September next year, and will cost about $36,000. This is way out of my price range, HOWEVER, I'm hoping that this engine will be released in the VW Polo. The Polo is about 200kg lighter than the Golf, so it would go harder in a straight line. Unfortunately VW already has the Polo GTi making 110kW, so I doubt it will happen. However, the next Polo GTi is meant to make 127kW, so I don't know if they're just upping the boost on the current motor, or if they plan on using the TSI. BTW, I forgot the acceleration figures, just for a point of reference. The Golf 1.4L TSI is meant to do 0-100 in 7.9 seconds, and 0-400m in 15.8 seconds. That's faster than a Corolla Sportivo (according to Wheels' figures), and they estimate that more potential is available as VW provided the figures and they put 200kg of weight in the car when doing the testing. I think I might have to see my mate at the local VW dealership and get me a test drive.

[rollacdmd]

YeaH saw that on the fifth gear TV show. In England that are already being produced and

got a rave review. They are going to be very popular and apparently since its been a sucess

they will be copied by alot of other car manufactors in the future they were saying. Great idea!

Edited November 24, 2006 by rollacdmd

[ancullen]

Pity VW are so confusing. They have FSI, TFSI, TDI, and now TSI engines. I'm lost. :jamie:

[ancullen]

BTW, bore is 76.5mm, stroke is 75.6. The TSI is a development of the existing 1.4L, which has a bigger 1.6L brother with the same 76.5mm bore, but an 86.9mm stroke. There are apparently no plans to use the TSI concept on a larger capacity engine, so don't expect to see a 1.6L TSI anytime soon. If it's successful on the 1.4L, I wouldn't be surprised if VW reconsidered though.

[rollacdmd]

It won't just be them producing these engines in different capacities.

I think the idea of using a supercharger and a turbocharger have

been around for a while its just that VW put it into action and have

definately suceeded!!

 

:jamie:

[7shades]

All fun and games until the little bitch torque-steers you into the guide rail... call me when the rear wheels do something other than hang off its arse.

[Mr Hardware]

I read this in wheels too. This is what i thought.

 

Unfortunately, these facts remain:

 

A 1.4L TSI produces 125kw & 240nm, which is very close to the standard camry 2.4L 4cyl

 

A 1.4L motor that has a turbocharger and supercharger probably weighs a very similar amount to a 2.4L camry 4cyl

 

and probably chews a similar amount of fuel, put in a similarly weighted vehicle.

 

 

I think it is a here today, gone tomorrow thing. I cannot see an engine like this possibly be a reliable alternative, let alone any benefit.

 

Don't get me wrong, i reckon it is a great idea, but i just don't feel that it will be economically viable, reliable, cost effective or anything like that.

 

125kw and 240nm out of a 1.4 is amazing, but the trade offs prove it irrelevant.

 

IMO

[7shades]

Lets not also forget the golf weighs about as much as a camry.

[rollacdmd]

7shades

 

none of us have yet said its RWD and thats its going to be exceptionally fast

all that the point in case is in a very very suburban city it would be wise to

purchase one of these which already it has been a huge hit in europe!

Edited November 24, 2006 by rollacdmd

[7shades]

Yeah sorry I'm a bit biased. I owned a 2001 golf gti turbo. it sucked.

[MRMOPARMAN]

well yeah, the 4agze would suck in comparison to that, VW has only had 20 freakin years to perfect it!

 

i do find the boost vs comp ratio interesting though

[Jason]

um of course the gze suks in comparisons, your comparing a brand spanking new motor to one developed in the early 80's

 

 

any way thats awsome, i want a car with 30psi of stock boost and twincharged :jamie:

Edited November 24, 2006 by Jason

[mattress]

I agree with Mr Hardware, i just don't see it becoming a big thing. If you want poke buy a GTI if you want economy buy the diesel. I just don't see too many people going for the mix of both.

 

A mate of mine is a service adviser for VW and is always bringing cars home. He had a polo not long ago. We pulled out onto the road and he gave it a good squirt. I said 'so what's this, 1.4 petrol' and he replies with, 'no 1.4 diesel'.

 

Now i must admit i havent driven or been in diesels since my old mans early 90's hilux but the polo pulled nicely and was so quiet. I was rather disappointed by the power delivery of the 4cyl turbo pasat. I guess after all, it isn't meant to be driven in a spirtited manner.

Edited November 24, 2006 by mattress

[Trev]

You also gotta look at the fact that a diesel engine normally has a compression ratio anywhere around 18.0:1 so running it at 10.0:1 is regarded as a decompressed engine, If you were to halve the C/R on a gze I'm pretty sure you could run around the 40psi mark safely (Backyarder runs 30psi reduced from 40psi in his 4AGTE 20v and runs 10's), And i doubt that you would be able to push much more from VW, Have you ever driven a turbo diesel, The new nissan navara has a 100kw diesel yeah it might be heavy but at the end of the day a diesel uses forced induction to aid it through the rpm range, I'm yet to see a full-on performance car based with a diesel.

 

 

 

EDIT:

Ha just realised the VW GT is A Petrol :jamie:

Edited November 24, 2006 by Trev

[MRMOPARMAN]

whoops, i thought this engine was a petrol lol. 10:1 comp in a diesel is farkin low. i thought most TD's used around 18:1 with 20+psi pumped in. ohwell I'm sure veedub knows what their on about.

 

oh has anyone been in a 2.0l TD golf with DSG? now the bloody GO!

 

i agree with trev, turbos turns diesels from a lump of useless shite into firestormers

 

those 114kw d30 navaras go real well for what they are too. especially without a tray :jamie:

 

my favorite diesel (to drive, least favorite to work on) is the 3.0l grand cherokee. they go like a cut snake!!

Edited November 24, 2006 by MRMOPARMAN