K04 Low Down Torque

[Toasted]

Hi everyone!

First post, first GTI!

Background to ownership:

Last year around early Summer, I decided to take the plunge from diesel estates (work/lifestyle related) and purchase a Golf GTI.
My initial preference being the MK7 in a 5 Door. After a lot of searching, mainly internet based, I struck a deal with a local VW Dealer on a 16 Plate one in Tungsten Silver. The car looked stunning in this colour (sunny day) and doesn't seem as common as other colours.
However, on arrival at the dealer to part with the full purchase amount, it was noticed that the car had been dented on the N/S Rear Wheel Arch - right on the crease, about 25mm up from the edge. Within an hour the defect was 'repaired' unbelievably badly by the dealer's "Magic Body Repair Man" and needed filling and paint as a result!!! At this point I got my deposit back and walked away.
It was also at this point that the guy (a friend of >15 years) who gave my a lift to the dealers mentioned about his MK5 GTI being still for sale (05 Plate, 5 Door, Steel Grey). I took it for a spin and was instantly impressed and parted easily with considerably less money than what was originally planned - win win!!
I couldn't believe how nice the car felt to drive, admittedly it didn't share the same top class cabin as the MK7, plus I felt it fell a bit short when pushing on, but in the real world where 80% of driving is undertaken, it was a real gem.

Ownership:

After owning this car for the best part of 6 months, I have still not tired in the pleasure of driving it, after having estates (albeit a couple were deemed 'sporty'), it is a joy to drive a smaller car again. However, as the car has now passed 150K miles and requiring a bit of mechanical and cosmetic loving, I am on the look out for a lower miler with no paintwork repairs, or at least, no bad paintwork repairs and a tighter feeling chassis and drivetrain.

K04 v K03:

The Edition 30 is a lovely car and one that is pretty much top of my list to purchase, however after doing some research and driving a couple, I am a little disappointed that the low rpm drive-ability of the K03 is lacking in the K04.
I get it - A smaller turbo spools up quicker - but loses puff later on, basically the opposite of the K04. I realise that the K04 is still a great drive, but it just doesn't have that 'easy' feel lower down the rev range which makes day to day driving a stand out positive for the K03.

The $64,000 question:

Can the K04 be tuned to achieve the same (or similar) low rev range drive-ability/responsiveness  as the K03 and still deliver better performance higher up the rev range?
Fully realising that you generally cannot have your cake and eat it!!
(The answer/s here could sway me away from purchasing a tip top K03 in favour of the better specced and more exclusive ED30!).


Many thanks in advance for any replies,

David

[Ripstop]

Short answer is probably yes (<cough><cough> R-Tech) ... (Other good tuners also available) 

[colesey]

Talented though Rtec undoubtedly are, they cannot change the laws of physics. Aside from the bigger turbo pushing the power band a bit further up the rev range, the ed30 has a lower compression ratio at 9.8 than the  k03 cars (AXX 10.5 / BWA 10.3) which will accentuate this characteristic. Using an upgraded hpfp will help the tuner bring on the boost a bit harder early on however the bigger turbo still needs more time to wake up...

[Toasted]

Thanks very much for the replies!
@Ripstop: RTech were top of my list when it comes to a tune.
@colesey: Thanks for the detailed answer about the K04. I'm thinking that the better option may well be taking a K03 to Stage 2 (or close to) state of tune.
Just went out for a blast to look at 2 'nicer' K03's but sadly, one was a bit pricey for what it was and the other made my 150Ker look new!
Will keep a look out, but it's getting tiring, beginning to think that I may well chuck a few quid at the car I already own...better the devil....

Thanks again for your replies  gents 

[ROH ECHT]

I have a K04 upgrade on a standard MK5 GTI. Yes, tuning can get you an abundance more low end torque over the stock K04 tune and the K03. I have two K04 tunes...one with 340hp and 363 lb*ft and another that is 360hp and 320 lb*ft. I prefer the first with more torque and I never even use the other. The higher torque tune also does a quicker 1/4 mile ET. I have some driving vids on my U-tube channel you can watch whenever. https://www.youtube.com/user/zoomdis/videos

[colesey]

@Toasted, I would recommend avoiding aftermarket intakes as they will lose low rpm torque and throttle response. Think Bernoulli effect and what larger pipes do to air velocity. They can also be pretty noisy, expensive and often mess up fuel trims. I think you may find stage 1 with a precat delete / dv+ / vis hpfp to be pretty satisfying on the road and a good starting point.

If you look at the photos section of RTec’s facebook page, you will see plenty of before and after dyno charts which will give you an idea of the type of torque curve you prefer. As Ron says above, torque is where it’s at and bhp is simply an extrapolation of torque against revs. You will know best what sort of rev range you typically drive in.

[Toasted]

@ROH ECHT: Thanks for the info 
Checked a few of your vids out - you have a very quick car there! The 0-120 run is seriously impressive  The torque is audible!!
The 0-120 run is seriously impressive 
Good to know that the K04 can do the business low down. I'm thinking that there's quite a bit of work gone into that car!!??
I see you're in Oregon - Whereabouts ?

[Toasted]

@colesey: Thanks again for taking the time and the advice.

With respect to the mods you suggest - I agree and add to that some handling improvement ones too, thinking anti-lift kit and ARB's.
Also, you mentioned about the aftermarket intake systems, after looking into them, I struggle to see any gains to be had on the K03.
Firstly and possibly mainly, I think they look bloody awful, with the exception being one from a Taiwanese Tuning Company (MST-Performance). I'm more than happy to admit any wrongful thinking here, but I fail to see how a bent metal tube with a cone filter placed out of position with the air ducting can make any improvement???!! As I've said, I'm all up for being proved wrong as solid proof never lies, however, the jury tips in favour of yours and my thinking concerning lower stage mods on the K03.

A few years ago I used to own a Saab 9-5 Aero Estate, quite a beast and embarrassed some 'higher' specced cars, admittedly it handled like a tanker but the straight line performance was stunning. This was tuned by a company in Essex called Abbott Racing (well recommended if anyone switches to a Saab) and they stated that the best bang for buck power/torque mod was a Stage 1 Re-map, 3" Downpipe and Sports Cat - which is exactly what I went for and what a transformation, it made an already pretty quick car, f***ing fast! The downside was the handling as it could catch you out if you got 'carried away'! Going back to the point/facts you have mentioned - I agree 100% plus a couple of handling mods to enhance the ride. A set of Eibach 20mm lowering springs are already in the wings and I would also look to add some sort of brake mod - but want to keep the car on the 17" Monzas it came with.

I will post the improvements as and when they happen.
Finally thanks to all on this site, it has a wealth of info and some clearly very well informed contributors.

Cheers

[colesey]

@Toasted - I fully agree about the handling upgrades and would add brakes to the list also. It is important to have a balanced package and you will feel the better response every time a wheel turns rather than just on WOT moments.

For the handling upgrades, I started with racing line sports suspension and later added H&R small arbs and the superpro alloy control arm kit with adjustable ball joints. All of this comes recommended for upto 7 tenths road use but if you drive harder then you may want stiffer suspension. Equally important is a good geo. More front camber and dialling out toe in will get your car turning-in more incisively.

Whilst on the drivetrain, engine mount inserts will keep the mass under control and for manual cars you add a few small tweaks to the gear change (s3 shifter / remove clutch bleeder restrictor / solid bushings) for a snickier gear change which also keeps the turbo spinning better.

On the brakes, the Mk7 R / PP 340mm set up seems popular however I went down a different route with endless mx72 pads / mtec c hook discs / bronze bushes which also works similarly well. These pads are quite spectacular tbh, streets ahead of the Ebc Red Stuff, and not overly expensive from Nengun.com.

I wish you luck!

[pudding]

I know what you're saying about K04 sluggishness off boost, however:

In terms of numbers, it might surprise you to learn that at 2300rpm, an Edition 30 is only 14lbft shy of an R32's peak torque, which arrives at a similar rpm.

The 'problem' with a K04 and it's perceived flatness is similar to the classic 8V GTI vs 16V GTI debate from decades ago.  The 16V was faster everywhere than the 8V on paper (otherwise why would VW bother making it?), but such was 16V's rapid rate of acceleration past 4000rpm, it made progress below that feel lethargic and less lively compared to the 8V, but the reality was the two cars were neck and neck until 4K (speaking from experience), and then it was see you later 8V!  Ditto K03 vs K04.

I've played around with K04 mapping with my tuner and I've seen 25psi by 3000rpm, so it's no slouch to spool up in reality.....but due to the sudden transition from onset of boost to full boost on the K04, that level of tuning isn't advisable because the engine's volumetric efficiency can't cope with that much boost thrown in at that rpm.  Most remappers have to reduce the boost around that area for that reason on K04s, otherwise you get a massive flat spot from the ECU freaking out.

At the rpms that matter for spirited driving, the K04 is faster, end of.  Bigger midrange and bigger top end, but the K03 is a great all rounder.  If you're not bothered about wringing the engine out to 7K, or shredding tyres at 3500rpm, the K03 is a great option 

[ROH ECHT]

@ROH ECHT: Thanks for the info 
Checked a few of your vids out - you have a very quick car there! The 0-120 run is seriously impressive  The torque is audible!!
The 0-120 run is seriously impressive 
Good to know that the K04 can do the business low down. I'm thinking that there's quite a bit of work gone into that car!!??
I see you're in Oregon - Whereabouts ?

Forty miles SW from Portland. Near McMinnville. Torque is priority for me, more so than HP. Of the two tunes I have...the one I no longer use(more HP) has more pull in 4th gear and beyond, but accelerates slower in the first three gears. The tune with more HP could never better its 1/4 mile ET of the tune with more torque. I no longer go to the track with it, so I prefer having the torque tune for driving the twisty back roads around here.

BTW, I agree with Pudding on the boost. With both tunes I have...I dialed back the boost. The one tune with more HP was initially done to peak at 26 psi and a 3 bar MAP sensor. With the WG preload being factory set, this tune was peaking at 28 psi. My tuner changed the tune so to peak at 26 psi, but I brought it down to 25 psi with a tiny bit less WG preload when I was running it. Mainly because the boost was peaking quite quickly and ignition seemed to always have trouble with high boost. I always had to keep fresh coils on hand and the right plugs(for mine = NGK PFR7B). Plug gap specs were very touchy as well.

[Toasted]

Hi Guys, thanks again for all of your inputs!

Firstly, @colesey: Great recommends regarding the handling - cheers. Without doubt I will be looking into the Superpro Control Arm set up - am I right in thinking this conversion goes above and beyond the anti-lift kit? As for your brakes - how do you rate them? At the moment I am enduring some judder under heavy braking (classic late braker) and therefore need doing soon, but I can't help but think there is no substitute for a bigger diameter - BUT - if a cheaper decent solution can be achieved by keeping the diameters the same, I'm all in. So, basically, are you happy that they do the job and have no regrets?
For info, my impatience has got the better of me and I have fitted a 'RaceChip S' tuning box for a quick fix of mo power - it has definitely highlighted the need to upgrade the brakes!!

@Pudding: Thanks for your input and bringing it down to 'feel' v figures. I agree with you, the figures are as near as dammit, yet there is still something going on which can't be put into words easily. Also, 100% agree with the MK2 8V v 16V comparison - that is so true! I have driven both and found I enjoyed the 8V more for some reason. I haven't owned either but have driven a few times, with a friend (the guy who sold me the MK5) owning both and also with him preferring the 8V, as you know, it's a known 'thing' in the MK2 community.
I guess this is the big dilemma, not only has my K03 got +150K on it, to me making excessive mods a waste of money and I love the ED 30 for many reasons, not least, the crazy potential it has.
Funny thing is that all that being said, I know when I walk out to the Steel Grey 05 Plate sitting on 17's I get a kick from it's almost sleeper like status. I know it has a GTI badge, but it's 15 years old and there are more overt looking low to mid-range newer cars out there - I like that the fact I can drive it and not draw toooo much attention, although I'm getting a little carried away round the town circuit as I love it's low rpm response from the line..... I wonder what the 0-30/40 times are for the K03 v k04??
Another reason the K04's are desirable is that 'generally' speaking, they have been cared for more by their owners than the straight GTI. It seems like there's many traps out there in K03 land!!
Got some thinking/endless Auto Trader/Ebay/Pistonheads/Gumtree/etc..etc  searching to do!!!!

@ROH ECHT: Thanks for your advice on the boost, I guess one thing that may differ between getting the max potential out of the K04 v K03 is the clogged up and speed camera heavy UK roads and rip off fuel prices! Tracking isn't what I'll be doing, I live a good few miles from the nearest one, which has quite tight noise level rules - So, fast road will be the driving, but like I said fast road UK v fast road US is quite a difference, especially in the current climate with the state looking at every way possible to bleed you dry.
Have spent a lot of time in the States, in various parts and know that it's not all roses over there too, but generally speaking, quieter less patrolled roads can be sought out. Not spent much time in Oregon, but have spent a fair bit in Washington State due to work. The roads around the Olypmic National Park are definitely K04 territory!!

To some up....I'm a bit confused to say the least - to a scientific thinking Virgo with a preference for the ED30/K04, just what is going on with the k03 and it's 'feel'??!!??
Also, don't lambaste me here as I know I haven't entered this world to save money - however - Will the K04 cost me significantly more to run? I ask, as a long time diesel owner (hence the love of torque I guess!!) who tried to find the perfect all rounder a few years ago by buying a Saab Aero Estate/Wagon. On paper it should have been on par (long term) to running a bland diesel estate, but in reality, when you end up driving it like an idiot everywhere you end up on first name terms with all the local petrol/gas station owners, eventually the repeated refuelling and parting with £'s wore me down!!

Thanks again everyone!!

[colesey]

Hi Guys, thanks again for all of your inputs!

Firstly, @colesey: Great recommends regarding the handling - cheers. Without doubt I will be looking into the Superpro Control Arm set up - am I right in thinking this conversion goes above and beyond the anti-lift kit? As for your brakes - how do you rate them? At the moment I am enduring some judder under heavy braking (classic late braker) and therefore need doing soon, but I can't help but think there is no substitute for a bigger diameter - BUT - if a cheaper decent solution can be achieved by keeping the diameters the same, I'm all in. So, basically, are you happy that they do the job and have no regrets?
For info, my impatience has got the better of me and I have fitted a 'RaceChip S' tuning box for a quick fix of mo power - it has definitely highlighted the need to upgrade the brakes!!

Hi, the superpro arms are made from alloy and @1.5kg lighter than stock though you could just as easily buy used Passat B6 lca as they are the same. You will need to add stiffer front bushes, either polybush or solid rubber s3 ones, as well as the antilift kit. I would recommend the superpro balljoints as they have slotted mounts to achieve upto 2 deg of neg camber and also have a revised roll centre to suit lowered suspension.

I'm very happy with the brakes and followed the advice in this link. You can buy the solid bronze bushes cheaper from Germany and Nengun sell the pads for @£135 ex shipping etc.

www.golfmkv.com/forums/index.php?threads/ultimate-brake-upgrade-using-stock-calipers.160406/

[ROH ECHT]

Hi Guys, thanks again for all of your inputs!
@ROH ECHT: Thanks for your advice on the boost, I guess one thing that may differ between getting the max potential out of the K04 v K03 is the clogged up and speed camera heavy UK roads and rip off fuel prices! Tracking isn't what I'll be doing, I live a good few miles from the nearest one, which has quite tight noise level rules - So, fast road will be the driving, but like I said fast road UK v fast road US is quite a difference, especially in the current climate with the state looking at every way possible to bleed you dry.
Have spent a lot of time in the States, in various parts and know that it's not all roses over there too, but generally speaking, quieter less patrolled roads can be sought out. Not spent much time in Oregon, but have spent a fair bit in Washington State due to work. The roads around the Olympic National Park are definitely K04 territory!!

To some up....I'm a bit confused to say the least -  I haven't entered this world to save money - however - Will the K04 cost me significantly more to run?

Right, I live out and away from cities so I am nearly always on twisty country roads. There are very few cameras here, sometimes a town may have one at an intersection where there have been too many problems with light runners, but some of those cams will also catch speeders.
Cost will depend on driving style, but when I first did my K04, I was still averaging over 28 mpg driving to work 30 miles away. I think I now have an injector issue as my mpg average is barely over 25 mpg...and its "LTFT-multiplicative" is near +10% with no leaks per my smoke testing. Plus, I no longer drive to work so all of the driving in it is shots to town and back. The thing that is important is upkeep. But having a tuned K04 build is...you are going to want to drive it like "Need for Speed or Fast-n-Furious". 

[pudding]

@toasted both are great options and I agree with you about them being under the radar, which is very appealing for me personally as I'm not a fan of the modern fascination with pops and bangs and/or stupidly loud exhausts.  I thought all that nonsense died out in the 80s/90s but apparently it's come back into fashion!

Visually the Edition 30 is just spot on imo. It's aged really well.  Similarly, a K03 on some nice polished 18" Monzas is also an eye catcher.  The Edition 30 in particular does seem to attract attention.  To me it's just a humble old Golf when I'm driving it around but people out and about seem to like it.  Some chap in the local Sainsburys carpark got out of his modded Audi S4 (way nicer than my car!) last week and was nosing around my car as I walked back to it. It was caked in mud as well!  And in the summer when I was at the dealer picking up parts, another customer asked me if I was selling it.  Apparently he was less than enthralled with his MK7 and regretted selling his MK5 some years back.  Seems to be a theme with late 30s, early 40s gentlemen 

Anyway, I would just test drive some K04s and see if you like that power delivery.  I would say a K04 running less than optimally will definitely feel lethargic off boost.  A good one should pull strongly from 2000rpm onwards in the same way a K03 does