Golfyste's road legal mk4 "project track car"

[golfyste]

Ok been thinking for a while that I want a afr gauge!

Been looking at the aem kit available...

http://m.aemeurope.co.uk/product_article.php?name=Digital-Wideband-Air-/-Fuel-Gauge&model=30-4100&prod=AEM-0158



The only problem is I don't really want to disassemble the downpipe to weld a new boss for the sensor.

my question is! Does the me7.5 Ecu actually need the rear lambda (post cat)?? Or is it purely to check that the car is working?

I thought is seen as I don't have a cat coil I just fob off the rear lambda and use that port for the afr gauge??



I'm looking forward to getting the running properly so I can get on a track day or too before the engine swap!

[Wazzzer]

that's a K03 you're comparing it to, not a K03s

Does look good though. I think one of the problems the cheap turbos can suffer with is the wastegate not sealing properly due to a poor surface finish; might be worth checking it out while it's off the car

[golfyste]

Yeah it is sorry 
Didn't even look at it just assumed k03s but forgot the track car with a k03 

Will try get a photo of the wastegate now!

[golfyste]

Ok pictures of the wastegate!

Looks quite good in my eyes.
Surfaces are nice and smooth!







Hopefully it will be £280 well spent 

[Wazzzer]

sound mate

We'll all be watching how this turbo fairs

[golfyste]

 

The plan is too hopefully get it to r-tech on Sunday an get a dyno print out and maybe get a devils own kit installed and do a few trackdays before winter sets in!

Then maybe buy a 4x4 for winter and take the golf off the road for the engine build/swap and maybe a few other little mods 

And then run the engine in and get it tweeked to see what I can push the turbo to!

[golfyste]

Ok its been a long day which to be honest hasn't been the smoothest....

Started pretty early so start with a few quite jobs 
removed the front bumper so i could remove the boost pipes and empty them of oil....



very nice 



Got on with removing the turbo....


Once i got the turbo removed i got slightly confused as i found there it pretty much no side to side play in the shaft 
So i spent a while getting annoyed and wondering what else it could be and all i could think was that the breathers are letting oil into the tip....which is possible but then also remembered i have been having to top the oil up just under every 2 weeks so surely it cant be that??

Anyway i decided to carry on with fitting the new turbo....
I slacked with the photos during reassembly as the turbo was being a real PITA to line up with the manifold!

random photo haha



I eventually managed to get it all sorted and changed over! as well as removed the plugs to clean of oil and check the gaps.

i then got it on the road and did a few logs
On actuator pressure...



As you can see the fueling on actuator seems good varying between 11.7 and 12.5 under hard acceleration

I then logged fueling and CF's with the n75 plugged in.



As you can see i have marked in yellow where the main acceleration is and that the fueling is safe.
But you can also see that my cf's are hitting 6 repeatedly!
correct me is i'm wrong but i read on rosstech that cf's of 5 or over are considered quite bad and need to be investigated further! is this right??

I was also experiencing a cut off boost and jerking while accelerating so i logged the boost and as you can see it seems to over boost a little and then it cuts it down to actuator and lets it build again...




What do people think?? All down to the map not being suited to the turbo or something more sinister?

A update on the smoking issue too!
I'm no longer getting smoke while driving which i was getting alot of before but i am still getting smoke on start up 

So think i may have to remove the pcv system next and install a catch can.


Sadly i don't think i will be able to run it on the rollers at r-tech tomorrow but i may cruise down on actuator pressure just for the sake of charity.

Any help advice is highly appreciated as always!

Cheers lads

[jamie16v]

hey ste, its the exact same turbo i have but at the time i bought mine, xs power were trading from wales.
i had very simular problems to you to begin with, overboosting like mad and retarding quite a lot too.
i didn`t use the standard actuator, i fitted a forge with a yellow spring but found the diaphragm to be leaking which meant the wastegate was being held shut. i fixed that and found it was still having a massive boost spike (25 psi settled down to about 15) at low rpm / high load and found that this was due to either the map or the n75 being unable to control the wastegate. i fixed this by temporarily fitting a bleed type 3 port MBC and set it to about 18psi (ive had it at a solid 20psi and it pulls crazy  ).
i was still having timing retard, mainly on cyl3 and found that this was because i still had the standard cat fitted due to putting it through the MOT. i fitted the decat and walla! running sweet.
i plan to fit a 2 port valve in parallel  with the n75 next to smooth things out as it is a little jerky when letting off boost.
on a side note, the turbo has been fitted a while now and still pulls strong and no issues so far.
oh, and from what i can work out, it has both k04 turbine and compressor wheels, so basically, a k04 in a k03s shell.
here, have a read http://www.golfgtiforum.co.uk/index.php?topic=118677.20

[golfyste]

Wow! Haha cheers for the info dude!
Good to know the turbo is still going strong I was considering changin it back but I may have to fit a mbc for the time being u till I can get the map tweeked and keep this turbo.

How do you go about fitting the mbc to work with the n75?

I currently have the standard actuator fitted as the holes in the bracket for my forge one didn't line up! 

Hmmm k04 internals mean potential higher 200's maybe 

[jamie16v]

How do you go about fitting the mbc to work with the n75?

http://uk-mkivs.net/forums/p/383118/2704970.aspx

Hmmm k04 internals mean potential higher 200's maybe 

indeed  as long as you have the fuel supply to cope, i.e bigger injectors, fuel pump/new filter and maf.

I currently have the standard actuator fitted as the holes in the bracket for my forge one didn't line up! 

contact forge, im sure theyll send you a bracket. luckily mine was a straight fit. there are three types apparently. the bracket didnt fit my old k03s.
or, just modify your current bracket to accept the forge actuator, all it takes is two holes drilling or notches grinded.