Author Topic: K04 remapped. Not impressed.  (Read 12798 times)

Offline AdzCM

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K04 remapped. Not impressed.
« on: April 09, 2015, 05:24:04 am »
Hello all, I recently got my polo remapped running standard compression, 77mm Wossners, BVH and 268 cam. Ran this with a K04-023. The turbo off a 225bhp Audi TT.

I'm sure some of you read my build thread and were maybe wondering how I got on.

All I can say is, I'm seriously disappointed. It made 201bhp and 178lbft using a circa 16psi of boost. This was conducted on an accurate hub dyno.

The powerband was around 4-6k

My tuner said that was it maxed before the K04 became inefficient, and he was right. Put up the boost to anything above 16psi and it made less power. Tested it on the road - upped the boost to 20psi = slower.

My problem is this. I think the K03 is the better choice and it's why I'm considering going back to it.

On the standard engine at 17.5 psi of boost, I got 170bhp and 220lbft. Ive noticed that 220lbft is more than any torque figure I've seen on here, but it's the truth and was on the same hub dyno. And truth be told, it was every bit as fast as it is now at 201bhp.

At 170 bhp and 220lbft on the K03, I could pull 120mph in 4th gear. I cannot do it now at 201bhp and 178lbft. I can get 118mph at 16psi. At 20psi I get 110mph in 4th gear. Proof it's making less power.

What is going on lol?

Is my intercooler too small for the K04?

Or is the K03 simply a better turbo for a smaller engine?

I've even done speed tests between two points (albeit it's not terribly accurate, but not too bad) and I can get nearly the same speed I got at 170bhp as I'm getting at 201bhp.

What are your thoughts?

Offline Alexiskayak_7

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Re: K04 remapped. Not impressed.
« Reply #1 on: April 09, 2015, 06:56:40 am »
Have you checked for pinking while making runs?
Are you remapping it while making power runs?


Offline GR40

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Re: K04 remapped. Not impressed.
« Reply #2 on: April 09, 2015, 09:55:28 am »
What was your power band with the k03? The k04 may just be a bit big for the engine meaning it comes in too late in the rev range to give you a usable torque curve. If you want to test if your intercooler is small for the turbo, spray it with water on the outside and see if it makes any difference.

Offline Yoof

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Re: K04 remapped. Not impressed.
« Reply #3 on: April 09, 2015, 11:46:50 am »
Are you measuring these speeds on the road, or dyno?

As you're not testing top speed, I'm unsure of the relevance of an in gear maximum speed measurement....

I.e. A stockish G40 will hit the same vehicle speed in 4th that a 250bhp Turbo will, as it's gearing/engine speed limited- not power in this instance.

If you have a good calibration for each setup (including a larger map sensor) then what you're concluding is:

Power increase of 15%
Torque reduction of 20%
Road drivability worse

Which, is nothing new: http://www.polog40.co.uk/forum/index.php?topic=8986.0

I would suggest changing the camshaft to suit a larger trim turbo, although this doesn't help massively with transient response, it would move the power further down the speed range.

But, the tried and tested K03 route is good, you're at the limit (or beyond it) of a stock drivetrain, transient response is good, and drivability is good provided it's calibrated well.

My tuner said that was it maxed before the K04 became inefficient, and he was right. Put up the boost to anything above 16psi and it made less power.

What was 'maxed' ?

Pics of the setup always help, and data- as much as you have


Offline AdzCM

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Re: K04 remapped. Not impressed.
« Reply #4 on: April 09, 2015, 01:30:22 pm »
Measuring speed on the road. I used to see many times what speed I could get by a certain point at 170bhp. Trying the same now makes little difference and I now have a diff which grips. Before at 170bhp I got loads of wheel spin but still made very similar speeds.

As for the gearing determining the top speed. I would have thought that. But a standard g40 can only get 120mph in 5th gear. At 170bhp, I easily pulled exactly 120mph in 4th at redline. When I turned up the boost with the K04 to 20psi from 16psi, it hit the limiter at 110mph. I don't know what to tell you there.

What my tuner meant by "maxed", is the power the K04 can provide. At 16psi it made 201bhp. We added more preload and the power went down to 196bhp. He said the turbo is now inefficient putting hotter air into the engine, less dense with oxygen etc.

Could it be down to the way it was mapped? He didn't have an EPROM emulator and so told me to fit an adjustible FPR. Because of this it runs a bit rich in the mid-range (shows on the graph that the torque/power dips a bit) and runs really rich at idle...probably why he only charged £100 ... It's impossible to find anyone in Ireland who can map EPROM. Believe me, I've tried. The reason the 170bhp K03 setup was so good is that he just altered Andys map. The map I got was to run a 65mm pulley/250cc injectors so he did something to it for the K03.

Would I be better off with changing to a K03, using Andys chip specifically for a K03, fit the standard FPR and have him map it again? Especially considering the cam is K03 specific according to you guys advice?

I guess I'm a little annoyed that I got a 30bhp increase with less torque. 20bhp of that likely came from the BVH and larger pistons. So really I got 10bhp from a larger turbo and threw away my torque, drive ability and response for nothing.

Andy warned me that the chip he made for me would not run that well with the K04 because it's tailored for a K03. Would the car run really well if I fitted a K03 and fit a K03 chip from Andy, or would I still need an EPROM emulator to get it setup right? Just wondering as it ran really well at 170bhp and my tuner didn't have an emulator then. He just altered the fuel or whatever in Andys chip.
« Last Edit: April 09, 2015, 01:47:52 pm by AdzCM »

Offline Andy

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Re: K04 remapped. Not impressed.
« Reply #5 on: April 09, 2015, 04:54:40 pm »
Speed in gear is a misleading measure of performance with a turbo, change the powerband by changing the turbo and you can find the car appearing slower if the powerband doesn't match the gearing so well.

The torque differences don't make any sense, unless the K03 runs were done in a lower gear than the K04 and/or your dyno man didn't calculate the gearing the same each time. Or the K04 is far far from optimised. Or both.

Your K04 is very unlikely to be "maxed" at that power. Much more likely that he's not put the correct timing or fuelling in at the high rpm that turbo will want/need. In fact, almost certainly if he's just messing around with an adjustable fuel pressure regulator. The last map point is at 6500rpm too, so needs some quite careful tweaking for big turbos (or the map re-scaling!) to make sure you can optimise spark and fuel.

That turbo is efficient enough to feed a TT's 1.8 20v motor and make 225bhp - all around the world, at -40°C or +50°C, even up the top of a mountain. Granted there are differences in engine efficiency, but primarily the power you'll get is down to the turbo - so your unit is a 225-270bhp turbo all day long. It may mean that achieving 225bhp on the little Polo engine means you have to do 7500rpm to flow the air to achieve it - but the power will be there.

What rpm was your peak power? With a bigish turbo like that and the 268deg cam it should be around 7000rpm, so should make some good hp numbers.

Drive the car to the UK for a long weekend break, and take your pick from any number of people that'll map Digifant - and it'll save you money in the long run! Have you asked your mapper how much it'd cost him to get an EPROM emulator? (Hint - it isn't thousands, or even hundreds of quid).

Alternatively, if you don't want to do that, follow the tried and tested K03 route and I can do you an off-the-shelf map that'll be fairly close to optimal - as long as the turbo you use matches. This might be the better option if you don't want to plough loads of cash into it. I think if you get that K04 working properly it's 225bhp all day long - which means you'll need new rods eventually and a good supply of gearboxes if Pete's big turbo 1341cc build is anything to go by...

Offline AdzCM

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Re: K04 remapped. Not impressed.
« Reply #6 on: April 10, 2015, 01:53:20 am »
You know what Andy? That's a reply I appreciate. Thanks for that. It did seem like a lazy attempt at a remap and he just wanted rid of me to be honest. I did ask him about the EPROM emulator and I said that would it not be a few hundred just, and he said it would cost thousands to work with his software. I accepted that as I'm none the wiser and wouldn't have a clue.

It made peak power/torque at 6k then tailed off. I have a printout I can put up tomorrow.

I would consider going over to the mainland for a day or two and get the most out of the K04. The K03 route sounds like a good route too. I will definitely take a good think about those two options.

I've already put so much money into it that, what's another bit to get the results I'm after. Though, the 'eating' of gearboxes is a little off putting and the amount of work Pete has put into fitting a different gearbox is way beyond what I could do. I don't know how he's going to be able to sell a setup like that lol. What started off as an adaptor plate, has turned into a serious amount of fabrication going by his thread. I'm just not there in ability.

Thanks again Andy. I'll put up the graph tomorrow.

Adrian

Offline AdzCM

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Re: K04 remapped. Not impressed.
« Reply #7 on: April 10, 2015, 02:06:33 am »
Also, you're right. He did do both runs in a different gear. When he was mapping for the K03, he used 4th. He tried using 4th for the K04 but his dyno was acting up, and he had to use 3rd gear.

Offline Alexiskayak_7

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Re: K04 remapped. Not impressed.
« Reply #8 on: April 10, 2015, 10:12:33 am »
There are emulators that cost thousands.
I bought a used one at a fairly price of 1000 euros. New ones costs 3000-3500. If he works certain software, then he has to buy only that tool.
BTW... I f he was a true pro he must squeeze his pocket to buy that tool...

Digifants are funny to tune. They are nothing compared to the tricore ecus that the cars run there days.

Offline ereeiz

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Re: K04 remapped. Not impressed.
« Reply #9 on: April 10, 2015, 01:25:05 pm »
Is there a reason people don't just swap to aftermarket systems like Motec or whatever? I'd have thought £500 or so to buy it plus setting up costs would be well worth it in the long run for better figures, more tunability, etc?

No idea on prices, that was from about 10 years ago. Must be free stuff out by now, surely?!

Offline Andy

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Re: K04 remapped. Not impressed.
« Reply #10 on: April 10, 2015, 03:07:18 pm »
There are emulators that cost thousands.
I bought a used one at a fairly price of 1000 euros. New ones costs 3000-3500. If he works certain software, then he has to buy only that tool.
BTW... I f he was a true pro he must squeeze his pocket to buy that tool...

Digifants are funny to tune. They are nothing compared to the tricore ecus that the cars run there days.
Professional emulated ECUs (by professional I mean the kit used by OEMs, not aftermarket tuners etc!) can run into tens of thousands of pounds. Emulators for 27C256 EPROMs can be had for sub-£300. Sure, if you want coverage of larger chipsets etc then you'll need to pay more - but just for Digifant it isn't crazy money for a tuning place to shell out at all.

Offline Andy

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Re: K04 remapped. Not impressed.
« Reply #11 on: April 10, 2015, 07:56:43 pm »
Is there a reason people don't just swap to aftermarket systems like Motec or whatever? I'd have thought £500 or so to buy it plus setting up costs would be well worth it in the long run for better figures, more tunability, etc?

No idea on prices, that was from about 10 years ago. Must be free stuff out by now, surely?!
Aftermarket stuff means you can have a bash at mapping it yourself, or find more people willing to map it - but if you're only doing it once the costs add up. If you're constantly messing with stuff, or want new features it can make more sense though.

Turbo conversion on a G40 already running Digifant is £300-£450ish to get remapped. Aftermarket management is £400 or so even if you go a cheap route (e.g. Megasquirt) by the time you've made a proper wiring harness for it etc. You've then still got to pay to get it mapped, at similar prices to Digifant.

Other thing to bear in mind, is with Digifant all the idle control; lambda control; fuel/spark temp corrections (air and coolant temp) etc. etc. are already calibrated - the mapper has to do little more than change the base fuel and spark tables, maybe a few other tweaks. With an aftermarket system, you're starting from scratch in those areas, and unless your mapper has access to a climatically controlled dyno (a few grand a day to rent usually...) they'll be working with generic calibrations for those functions. It'll all work okay, but will need much much more time putting into a calibration to get it as refined as a quick dyno Digifant cal.

Horses for courses really. For some situations, aftermarket stuff is the way to go.

Offline AdzCM

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Re: K04 remapped. Not impressed.
« Reply #12 on: April 12, 2015, 07:08:57 pm »

Offline Yoof

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Re: K04 remapped. Not impressed.
« Reply #13 on: April 13, 2015, 07:10:52 am »
Testing in 3rd means the turbo will spool later than in 4th. Also you've got a correction factor of 1.15 (+15%) so are the figures quoted as observed, or corrected?


Offline AdzCM

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Re: K04 remapped. Not impressed.
« Reply #14 on: April 13, 2015, 03:54:11 pm »
Testing in 3rd means the turbo will spool later than in 4th.



What are you saying?

And, I have no idea whether they were observed or corrected :S sorry.