Got my car re-tuned again after having creep issues with the classic sidewinder 90* single 44. We blamed it on the gate size/angle and i ordered the Prayoonto AWD manifold with a 60 gate, put a 9.77 lb spring in the 60 gate and had it rise to 20lbs on 2 pulls car made 593 while spinning and and slipping on the roller. It HELD at 20lbs, important specs are as follows k24a2/k20z3 head 100% stock engine , PTE 6266 .81 AR T4 JB. I have a friend with a gt3582r sleeved k24/20 using a single 44 90* gate and not creeping. So why am i still creeping with this manifold, tuner blamed it on too small an AR housing however a guy builds race engine etc said it's the wastegate placement.


This is it,

 

Wastegate angle is still not in the flow path of the exhaust gasses technically. It could also be due to running very low (slow) ignition advance - this can lead to boost creep.
A "too small" turbine housing will have the opposite effect of boost creep - the turbo will restrict itself due to increasing backpressure. The 0.81 T4 seems spot on for a K24 to me.

The PTE 66mm turbine definitely flows more than the 62mm Garrett so that could be one reason for the difference in behavior between the two setups. But check your actual wastegate and make sure the valve is free to travel all the way.

 

I don't have a data log to check that, but can you elaborate on the timing being retarded too much?

 

I never use this language to people i dont know but if you told your tuner a guy with gt3582 did not creep while your creeping have a 6266 with a T4 0.8 a/r housing, he doesnt have a clue what the F he is talking about if his responce was "small turbine housing is causing it".
GT35 62-68 turbine wheel is a midget flow restriction wise compared to the 66-75 turbine wheel. If your turbine wheel is creating 15% less restriction you need a wastegate exit that flows at the same pressure 15% more or 15% more air will choose the path of your turbine wheel because pressure ALLWAYS EQUALISES among two paths.
This manifold has a very bad exit and its for HIGH pressures inside the manifold. We are talking about something like 2 bar inside. Well at 2 bar back pressure at above that manifold will work like a charm. I believe its a race manifold and thats it.
If your turbine housing was "small" it would create more pressure in the manifold and more gases would pick the wastegate exit route.
Get a T4 .58 and youll have much better boost controll and will be able to hit ~650whp with that turbo. It will be like T3 ~70 a/r but with a super high flow turbine wheel in it i guessing like 25-27lbs of turbine flow. Enough for 650 whp with such an efficient setup. plus it will be a LOT more fun on the street...

 

I've never been too impressed with his mechanical knowledge but is popular here in the GTA and many ppl use him. The car i'm referring to is one he tuned, but that aside that, pretty much everyone i've talked to has said the same about the gate being in a **** position. The only other guy i know of using this exact manifold on the street.has BBG for 1st only and makes 25psi on a 72mm precision in 1st then 38psi the rest of the gears till 1000+hp. So with a smaller A/R i'd be able to have BBG despite the shitty gate placement.

 

Yes that .58 will work very well on your setup. It will help on the creep problem but i cannot guarantee it will solve it 100%. It will help tho and probably very well.

 

your downpipe looks like to big 3,5"???. i have a k20a2 turbo and im using my own fabed sidewinder with 44mm tial mvr, gtx3582r gen2 and holds 8psi low boost on all gears. t4 is very big compare to t3 flange. i would use a selfmade copper/stainless steel t4 gasket with t3 open port and a smaller downpipe diameter. bigger downpipe = less backpressure inside manifold = boost creep

 

4" hood exit, creep issues are alot less common for the k20s here, the k24 paired with a k20 head is another story.



I have since looked at the Datalogs from those pulls and sent them to my friend who knows alot more about this stuff than i do. Timing wasn't retarded AF/R was fine(not rich) however the car starts building boost at 3600 and hit 20psi at 5000 and HELD it all the way up to 8200 RPM. here's the thing, the boost solenoid(controller) is set to 40% duty yet is disabled. What's confusing is that it made 20psi and held it for over 3000 rpms.the last time it just got out of hand and hit boost cut 24lbs ar 7000...

 

Was this with the solenoid enabled? May have found your problem if so..

 

I don't have the data logs from that time sadly. But it does make me wonder now that we discovered this. Looked at the earlier ones it does creep from 9.7 to 15 and hold, one of the logs is that pull(no controller duty). The 593whp pull has the boost controller at 40% duty and made 20psi by 5k and held to 8200. i don't know how to read the logs so this is what my friend has told me and does add up to what i'm looking at in the basic view of K manager. So does it creep, yes but nowhere near what i thought it did, glad i put the 10lb spring in vs the 15. The plan for the car is to build the block and shoot for 830whp on q16 for 2021 season.