RoRu

Andy,

Have you any ideas why i'm getting some creep?, my wastegate has already been ported by you. (one of your 20G's)

The car is mapped for 1.48 bar max but on the road i've seen 1.61, is this enough to worry about?

I don't have any AFR gauge so i'm not sure if it runnig lean, but the knockLink is very quite.

Andy.

Andy.F

Andy

Have you been through the procedure of ensuring minimum preload on the wastegate actuator and a clear exit from the wastegate opening ? ie open neck downpipe.
Is your 1.61 bar a spike or a held boost figure at high rpm ?

Andy

RoRu

Andy,

1)Have you been through the procedure of ensuring minimum preload on the wastegate actuator.

Not sure what you mean?

2)A clear exit from the wastegate opening.

No i'm still using a closed neck Hks d/p.

3)Is your 1.61 bar a spike or a held boost figure at high rpm.

No i think it's only a spike.


Andy.

JDM_Wrx

thanks for your advice Andy F. i now know what i'll be doing tomorrow morning...


cheers
Rob

wrrjones

I dont think it DP related ether as i have fitted a few non open neck dp,s and they have been way better with boost creep . I think you prob my be with the HKS boost controller .
chris

Mark A

iTrader: (1)

Andy do or did you have pictures of this, before & after

Mark A

Mark A

iTrader: (1)

Is this true it's taken from a US website

"Porting the wastegate is a quick fix but has it's disadvantages. The one main disadvantage is the VF39 turbo will not make as much power when the wastegate is ported and the ECU is properly programmed. Where as when the car is properly setup and programmed with an unported wastegate the car will make more power".

john banks

I thought JDM_Wrx had tried a direct connection from compressor outlet to actuator and it still crept? Still can't understand why you don't map it/get it mapped to run higher than the boost creep level? So far because of the fuel cuts, you don't know how high it might creep?

JDM_Wrx

wrrjones - the hks controller is out of the equation. i have a direct pipe from turbo to actuator and still have creep. this all come about by trying to set up the hks controller.

JDM_Wrx

john banks - if i disconnect the actuator rod and then drive it with a direct pipe from turbo to actuator, will this show me how far the creep goes? if it creeps to below the fuel cut then can i set the boost controller up to cater for it.

would it be easier to do what andy f suggests and port the waste gate, are there any down sides to doing this?
i see what u are saying about mapping to a higher level but i don't have a front mount i/c to cope with boost levels greater than about 16 psi.

john banks

Yes, but if you've used a direct connection I doubt you'll fare hugely better.

Porting the wastegate is the best solution if you want to run less than the level it creeps to.

JDM_Wrx

are there any downsides to porting the wastegate?

John Banks and Andy F - thanks very much for your help in this matter, i know u are both very busy men.

cheers Rob

john banks

If you port the wastegate incorrectly, yes you can ruin spool up, say if there are any leaks so the "penny" can't seat properly.

Andy.F

Ok, if it is a spike then your problem is with the boost control, not boost creep. Boost creep is where the boost continues to rise uncontrollably at high rpm (usually around 6-7k)

I don't have any pics Mark but if you look on the wastergate hole, you will see the clean area where the valve has been sealing. Just port out the inside of this hole leaving at least a 1mm seat for the valve to seal against.
Regarding the power reduction, yes if you run less boost then you are likely to have less power. Assuming the ECU/controller is set to still achieve the desired boost, then you will achieve the same power regardless if the w/g is ported or not.

Andy

JDM_Wrx

hi, thanks to delboy, i now have a ported turbo housing, i fitted it last saturday and everything is now sorted. just need to setup my boost controller and i can get my remap and its back to the rollers to see if i've got my original target of 300 bhp and good torque.

the ported housing has stopped the creep, it now holds 8psi right to the red line, this being with a direct pipe from turbo to actuator. also, turbo now spools up quicker, it seems to spool around 3,200rpm where as when i original fitted my headers spool was around 3,800.

anyway, thanks for everyones help.

time to enjoy!!!