Hybrid K04 Turbo Discussion

[DPJ]

Some more logs tonight @ 110% Vtune boost. midrange boost has increased but redline is slightly down. How do you think my fueling looks. OAT was 17 degs for ref.

Vtune @ 110% boost RPM Load % Requested boost Achieved boost Requested lambda Achieved lambda
3280 131.6 2040 1580 0.984 1
3520 189.5 2400 2350 0.852 0.906
3800 191.7 2550 2540 0.867 0.867
4080 191.7 2550 2540 0.867 0.852
4360 191.7 2550 2540 0.836 0.852
4640 191.7 2550 2540 0.836 0.852
4920 191.7 2550 2540 0.844 0.852
5160 191.7 2540 2500 0.852 0.852
5400 191.7 2480 2460 0.844 0.852
5600 189.5 2440 2440 0.828 0.852
5800 188.7 2400 2420 0.828 0.852
5960 185.7 2370 2310 0.844 0.852
6120 173.7 2350 2330 0.813 0.852
6280 176.7 2330 2240 0.844 0.852
6440 174.4 2320 2220 0.86 0.852

Not a lot wrong with that, Carl! The fuelling isn't really running leaner than it's target until 6440.....

 

[Mitchy]

I measured the length of my rod today! (oow err..)

Its 22mm

You done some fiddling already then Sie?

Looks like i need to tighten mine down quite a bit. 20mm from edge of slider to end of rod for me. You at 22 and Carl at 25.

Need a new N75 1st tho, mine is fecked!

 

[YerMother]

Yea after the manifold was fitted i put a couple of revolutions on it, but never measured it untill yesterday. Thought it maybe a good comparison!

 

[YerMother]

I don't think we are going to get much more top-end as the A/R of the turbine side is far too small to allow the flow higher up the rpm. The back pressure is so great that you'd have to weld the wastegate shut! Remember it's never fully closed anyway as the APR code only allows 95.4% N75 duty cycle. What's your wastegate doing at 110% vtune now then Carl?

 

[wild willy]

Not a lot wrong with that, Carl! The fuelling isn't really running leaner than it's target until 6440.....

It gives me some confidence that the mixture is still rich. Its curious that the lowest A/F lambda ratio that i can measure is 0.852.

 

[wild willy]

I don't think we are going to get much more top-end as the A/R of the turbine side is far too small to allow the flow higher up the rpm. The back pressure is so great that you'd have to weld the wastegate shut! Remember it's never fully closed anyway as the APR code only allows 95.4% N75 duty cycle. What's your wastegate doing at 110% vtune now then Carl?

I think your right Simon , I've always woundered why APR only allows 95.4% duty cycle.... a safety precaution maybe. I'll try and fit the J valve this weekend and get some new 118 logs .

 

[ibizacupra]

are you guys also looking at egt?

 

[DPJ]

are you guys also looking at egt?

(Not my thread, but) You mean I should have got Ian Birch to put me a sensor boss on my new dp, Bill. Any easy way round in now?

It gives me some confidence that the mixture is still rich. Its curious that the lowest A/F lambda ratio that i can measure is 0.852.

Not with you Carl, you've got a 0.813 in there. (Have you been labelling columns, I was under the impression first Lambda column is actual, second is target..... )

 

[ibizacupra]

I bought one from the USA which had a strap arrangement to clamp its boss to the DP. Not sure how effective it would be tho.. I had an 1/8" npt boss welded in my DP, which is the common size they come in.
maybe if your DP has sufficient wall thickness, you can tap the thread. (maybe)

 

[ibizacupra]

I think your right Simon , I've always woundered why APR only allows 95.4% duty cycle.... a safety precaution maybe. I'll try and fit the J valve this weekend and get some new 118 logs .

Apexi only allows 90% max duty cycle

 

[YerMother]

are you guys also looking at egt?

Max exhaust temps i've seen has been around 850'C

 

[wild willy]

(Not my thread, but) You mean I should have got Ian Birch to put me a sensor boss on my new dp, Bill. Any easy way round in now?



Not with you Carl, you've got a 0.813 in there. (Have you been labelling columns, I was under the impression first Lambda column is actual, second is target..... )

Lol, its quite possible the entire time I've been logging i've got it wrong, as i always thought requested was L/H column and actual was R/H column.
the column labels are my own. I could have sworn that boost requested was L/H column and achieved was R/H column and i applied my own logic that Lamda followed the same. It would appear if i follow my own logic that I'm a little lean with respect to requested but on the whole it still appears richer than many I've seen mapped.

 

[ibizacupra]

Max exhaust temps i've seen has been around 850'C

nowt wrong with that

 

[wild willy]

Max exhaust temps i've seen has been around 850'C

What channel no is exhaust temp on vagcom.

 

[YerMother]

112! I think it may be around 900'C actually see what your getting!

 

[wild willy]

112! I think it may be around 900'C actually see what your getting!

I did a few logs tonight and max temp of channel 112 was 900degs.
I changed to a J valve which held boost a little better. (118)

4200 27 44.7 1010
4280 27 71.8 2260
4680 27 74.9 2540
5080 26 75.7 2540
5400 27 77.3 2420
5680 27 86.3 2430
6000 29 93.3 2360
6240 30 95.3 2280

 

[DPJ]

No other issues from the J valve, Carl?

Would someone do me a big favour and log 112 and 043 (Cat temp) together to give me an idea of the temperature gradient? (LC doesn't have a sensor for 112)

 

[wild willy]

No other issues from the J valve, Carl?

Would someone do me a big favour and log 112 and 043 (Cat temp) together to give me an idea of the temperature gradient? (LC doesn't have a sensor for 112)

The J valve is a little bit aggressive on part throttle response but not to bad.
I'll try and get some logs sorted for you in the next few days.

 

[Mitchy]

Carl, do you run an in car boost gauge?

I tightened down to 22mm at the weekend, not done any formal logging but boost seems to be holding a little stronger top end, however it does have an effect on boost creep issues. If i have to climb an incline on part throttle, gauge will go around to about 14-15psi and then drop. I need to keep correcting it by going off throttle, back on.

Still not sure if this is N75 issue or wastegate too tight. Was just wondering if you are seeing similar part throttle issues and unwanted excess boost?

Think ill put it back to the standard 16-17mm measurement and then see if it still happens. If so, i can then determine its definitely down to N75 and not too much pore load on actuator.

 

[wild willy]

Carl, do you run an in car boost gauge?

I tightened down to 22mm at the weekend, not done any formal logging but boost seems to be holding a little stronger top end, however it does have an effect on boost creep issues. If i have to climb an incline on part throttle, gauge will go around to about 14-15psi and then drop. I need to keep correcting it by going off throttle, back on.

Still not sure if this is N75 issue or wastegate too tight. Was just wondering if you are seeing similar part throttle issues and unwanted excess boost?

Think ill put it back to the standard 16-17mm measurement and then see if it still happens. If so, i can then determine its definitely down to N75 and not too much pore load on actuator.

No boost gauge mate. I've not had any boost creep issues as yet (not according to vagcom). Try a new valve. I doubt you'll appreciate the pull of the turbo until you have the ability to dial in more boost. Your probably meeting requested boost from your map already.