Revo Stage 2 Logs PAGE 3 HOLDING CRAZY BOOST***

[ibizacupra]

tufftys cat had shrunk in its housing and turned 30 degrees the the axis of flow, blocking it significantly, so never say never is one of my motto's

trying to figure out hwo its holding boost, (if) its not a mutant k03s

all I am doing is running along the lines of its flow will be limited by its spec, and your airflow is not more than a k03s will move, BUT, its blowing thru something which is holding pressure upstream of the map sensor for some reason.. the analogy in my mind is its trying to blow thru a small pipe, holding up boost pressure, but not equating to flow.

achieve flow from the engines, and they make power.. Boost is just a means of shoving in said air.. If it does'nt want to flow, you can blo was hard as you like and it wont flow much more

Historically, my ibiza when ihi'd suffered a low of power/flow, and seemed to strain at higher revs where it did'nt used to..
then I looked closer to try and figure out what had changed, restricted something, and never expected to see this!!

that used to be a 2.5" bore flexi pipe before is ruptured inside and turned into a very small phincter! lol

its deffo an odd one for sure.

 

[James.Judd.1]

Well it cant be anything induction side anymore, it was like this before I had everything off so I can confidently say its not something I have done, it has adequatly sized boost piping as it is all from the forge kit which is deffinately good for k03s power..
What else is there after the MAP sensor appart from TB that could produce a blockage???
I will fit the resistors and get the DP off at the weekend and report what I find.
Cheers!

 

[James.Judd.1]

Calculated my IDC's and it appears they max at 4700rpm.. which is also the same time the g/s stop increasing.. could this be a part of the reason..

Nifty little spreadsheet Bill

EDIT: I know what your going to say.. get wideband!

 

[Wak]

Sorry for being lazy in reading the entire post but has the turbo actuator been checked for crack pressure and travel?

Does the Manual Boost controller have different boost settings by rpm or fixed boost level accross the rev range?

 

[James.Judd.1]

Sorry for being lazy in reading the entire post but has the turbo actuator been checked for crack pressure and travel?

Does the Manual Boost controller have different boost settings by rpm or fixed boost level accross the rev range?

Hasnt been checked, but with the MBC wound right down (wastegate pressure) it cracks at 7psi ish.

And MBC is a fixed boost level.

 

[Wak]

Worth reviewing the crack pressure I think and more importantly travel. We had a K04 in recently with 9psi crack pressure and a virtually stuck actuator.
1.44 bar being held at the redline, after we set the CP to 5.5 and with the N75 disconnected!!!!
(Just to mention, this was an Ebay clone K04 that this poor soul had invested in)

7 psi sounds high for a K03 its typically 5.5psi on a K04!

(Maybe someone can confirm the K03s crack pressure, I havent seen many to be able to confirm what it should be)

 

[James.Judd.1]

It is an uprated CRTurbos actuator not standard.. BUT it came with the car and I am unsure what crack pressure it is meant to be..
Im am not very clued up on how to test and check for crack pressure and travel..

 

[Wak]

You need a pressure gun like a mitivac, and pump the feed to the actuator until you see the rod move, ideally feel the preload release which is crack pressure and then continue pumping to see linear movement and a reasonable amount.

If it cracks and you get to 15-25psi and the rod isnt moving then this could be the cause of an overboosting situation.

Its one avenue to check ....

 

[James.Judd.1]

You need a pressure gun like a mitivac, and pump the feed to the actuator until you see the rod move, ideally feel the preload release which is crack pressure and then continue pumping to see linear movement and a reasonable amount.

If it cracks and you get to 15-25psi and the rod isnt moving then this could be the cause of an overboosting situation.

Its one avenue to check ....

Cheers mate.. iv got a compressor at home.. but the only guage is on the tyre inflator.. im sure i can fit an old tyre valve in the actuator line and bodge something up

 

[Wak]

Cheers mate.. iv got a compressor at home.. but the only guage is on the tyre inflator.. im sure i can fit an old tyre valve in the actuator line and bodge something up

nooooo lol

you need more fine control you dont want to rupture the actuator!

 

[Wak]

Hasnt been checked, but with the MBC wound right down (wastegate pressure) it cracks at 7psi ish.

And MBC is a fixed boost level.

sorry so with mbc turned down do you have a log that shows the boost profile? one of the pictures above ?

 

[James.Judd.1]

nooooo lol

you need more fine control you dont want to rupture the actuator!

Haha good job you stopped me! Hmm I will have to get someone else to do it then..

 

[James.Judd.1]

sorry so with mbc turned down do you have a log that shows the boost profile? one of the pictures above ?

Nope but I could do one tonight.. I do notice the boost creeps up when on wastegate pressure to about 10psi in the higher rpms.. actuator is starting to sound like the likely culprit

 

[James.Judd.1]

http://myustools2.amazonwebstore.com/Silverline-Automotive-Vacuum-Pump-Kit/M/B0002SQYUA.htm

Is that what I want?

 

[Wak]

Is that what I want?

no, thats vacuum, you need a pressure gun but it may be a waste of money if you are not seeing high boost with the mbc turned down.

How are you setting the mbc ? How do you set the boost level?

 

[James.Judd.1]

no, thats vacuum, you need a pressure gun but it may be a waste of money if you are not seeing high boost with the mbc turned down.

How are you setting the mbc ? How do you set the boost level?

Oh yes i didnt notice it said vac, I do have a small hand pump thats used for pumping up the shocks on push bikes thats quite accurate.. that might work it has a very small piston..

I set it to clip the spike at 24psi.. but the turbo holds 20psi after then.. so the wastegate would be shut constantly after the initial spike.

 

[Wak]

Maybe I am getting confused here but in my "limited" experience if you have a manual boost controller which has a single setting and you set it to 1.65 bar surely its going to try and maintain 1.65 bar accross the whole rpm range !

hence why you have crazy boost! If you want it to run sensible boost from the k03s , for example, run 0.9 bar at 6500rpm then your mbc needs to be set to 0.9 bar no?

Also , is your Air mass meter healthy?( new)

 

[James.Judd.1]

I checked the actuator and it fully opens at around 7psi.

Most maps ask the turbos for more boost than they can produce.. so basically the turbos are always flat out.. this is exactly what im doing here by setting it at 24psi, making the turbo work flat out, but clipping the overboost.. the fact is these turbos (k03s's) cannot produce 1.35bar at 6000rpm even when they are flat out.. especially as the g/s dont match up to that amount of boost.
This seems like there is something causing back pressure between the MAP sensor and the Inlet manifold.. meaning there is high pressure but not the airflow to match..
BUT everything has been off and checked and this is not the case..

 

[James.Judd.1]

MAF sensor is about 3 months old so that should be fine

 

[Wak]

Do you have a boost gauge to confirm what the map sensor is seeing ?