Finally bought a GTI - Anyone recognise it?

[AJP]

@AJP can you elaborate on this?

Are you saying that his log of 150bhp was a snapshot when torque was highest? Could his bhp have been higher at some other point on the dyno?

One of my old graphs. Ignore the Stage 1 curves.



Standard k03 engine, producing peak TORQUE of 220lb/ft at 2200rpm. Which equates to about 120bhp, at 2200rpm.

Peak POWER at a shade over 200bhp at 6000rpm. Which equates to about 175lb/ft, at 6000rpm.

Imagine the torque curve peaking identically at 220lb/ft @ 2200rpm, but instead of tapering to 175lb/ft @ 6000rpm it tapers to say 130lb/ft @ 6000rpm (due to possible boost problem).

That 130lb/ft @ 6000rpm would make, for argument's sake, 150bhp @ 6000rpm, and constitute the peak power figure.

So although the OP's engine is apparently making the correct stock peak torque figure, it's entirely possible to be well down on peak power at the same time.

[AJP]

Thanks for all the great feedback gents.

I would like to remove the Forge DV in place for the Rev G DV but will need to spend some time reading the install instructions for the Forge one as it appears to be more complicated than just a plug and play DV. I.e. removal will be more complicated.

This was my dynograph for those interested, colours are a bit hard to differentiate but the curve starting at 34 is power and the other therefor is torque:

You posted this as I was posting mine, and I don't think I'm too far off on my suggestion. Looks like your torque is dropping off too much.

Are these figures at the fly or wheels though....?

[Vish8895]

@AJP can you elaborate on this?

Are you saying that his log of 150bhp was a snapshot when torque was highest? Could his bhp have been higher at some other point on the dyno?

One of my old graphs. Ignore the Stage 1 curves.



Standard k03 engine, producing peak TORQUE of 220lb/ft at 2200rpm. Which equates to about 120bhp, at 2200rpm.

Peak POWER at a shade over 200bhp at 6000rpm. Which equates to about 175lb/ft, at 6000rpm.

Imagine the torque curve peaking identically at 220lb/ft @ 2200rpm, but instead of tapering to 175lb/ft @ 6000rpm it tapers to say 130lb/ft @ 6000rpm (due to possible boost problem).

That 130lb/ft @ 6000rpm would make, for argument's sake, 150bhp @ 6000rpm, and constitute the peak power figure.

So although the OP's engine is apparently making the correct stock peak torque figure, it's entirely possible to be well down on peak power at the same time.

Thanks so much for the in depth detail in your explanations, that has cleared a lot up!

I am letting the dealer's garage assess the issue in the first instance but i doubt they will be familiar with the Forge DV so God knows what they'll do or find...


Thanks all :)

[Vish8895]

I think they are at the fly, when it was on the tuners old dyno they quoted WHP with an estimated bhp. On this one they're quoting bhp so I imagine at the fly.

[AJP]

No problem mate. I'm sure you'll get it sorted quick enough. DV issues and boost leaks don't usually cause much head-scratching!

[Vish8895]

No problem mate. I'm sure you'll get it sorted quick enough. DV issues and boost leaks don't usually cause much head-scratching!

Yeah I didn't think they would but having only owned the car 24 hours I thought I best get the dealer to sort it rather than me start messing and possibly void my rights!

[lukemk5gti]

Thanks @AJP

What I can see though is over the entire rev range, his dyno only maxes out at 150bhp. I thought at one point over this graph it would have gotten close.

Is something amiss here? Is his DV/PCV the likeyl candidate and a second run after this fix would show closer to 200bhp over the range?

[AJP]

Thanks @AJP

What I can see though is over the entire rev range, his dyno only maxes out at 150bhp. I thought at one point over this graph it would have gotten close.

Is something amiss here? Is his DV/PCV the likeyl candidate and a second run after this fix would show closer to 200bhp over the range?

Well yes... I think we've established that something is obviously amiss here.
If you look at the graph I posted you'll see how a healthy k03 dyno looks. Compare that to his.

Firstly, it's reaching peak torque much too late, towards 4000rpm. Then immediately dropping off. It's almost impossible to say what exactly is causing this just by looking at the graph, but making sure the DV, PCV, cam follower etc are in order is good general practice to start with.

[Vish8895]

Hi guys,

Sorry for going quiet, I have been on holiday for 2 weeks! Itching to get back and get this leak diagnosed.

Visited Niki down at R-Tech today and he was really helpful. They smoke tested it and straight away we could see smoke coming from behind the engine.

Niki and the lads pulled the Forge DV off and replaced it with the Rev G. The Forge DV was covered in oil, making it very clear it was leaking.

As soon as the Rev G DV went in the car felt so much better. Same pickup and go, but rather than dying down after 4k revs it just kept pulling like it was going to rev forever.

Very grateful to the lads down at R-Tech for sorting her out and now looking forward to doing a MAJOR service inc. the cam follower.

[Dan_FR]

Great news, testament to R-Tech and their customer service and yet another leaky Forge DV.

Enjoy!

[Vish8895]

Yes I am very happy to have her running healthy!

Checked the cam follower today, the car is currently at 80K with no documents to say the cam follower has been changed. Looking at the condition of the follower and the o-ring on the HPFP I would say it looks like it has been changed. I think I will wait to replace it until I do a full service in the coming weeks.