Boost creep!

[crispyeel]

Wondering if anyone else has issues with boost creep?

My EP91 is running the stock turbo, Japspeed cat back, HDI front mount & air filter relocation I have recently fitted a hks actuator and set it to .7 to start with

On the first test run, the car would boost fine to .7 then in the higher revs it would shoot up to almost 1 bar then hit boost cut. I have now set the actuator back to stock boost and it still overboosts and hits cut in most gears

This is driving me mad! Can anything be done to stop this? I have read into setting the piping so that you can still use the hi-low solenoid with the hks actuator. Would this help?

Edited December 3, 2014 by crispyeel

[Ollieh17]

The effective way around it is to port the wastegate of the ct9 or go externally gated

[daniel_g]

This is pretty standard with doing breathing mods to a starlet still on CT9, especially in this freezing weather. The wastegate penny is tiny on CT9s. You can try port it out a bit. Or put the stock air intake back on see it that helps. Or best bet get an external wastegate turbo kit.

Could maybe even get an exhaust bung in the back try restrict flow. Ive seen other cars use a ring in the exhaust to stop it boosting too high, but havent seen anything like that for a starlet yet.

[toyotag2014]

ive got the same problem with mine and mine is an auto thought it might of just been me bought a turbo ct9 hybrid with bigger port speedvision gen 2 turbo and had a filtr relocation to the front and turned my hks actuator down to .7 and .6 but keeps boosting up to a bar of boost when it changes up a gear on mine

[daniel_g]

ive got the same problem with mine and mine is an auto thought it might of just been me bought a turbo ct9 hybrid with bigger port speedvision gen 2 turbo and had a filtr relocation to the front and turned my hks actuator down to .7 and .6 but keeps boosting up to a bar of boost when it changes up a gear on mine

Try and put the filter back in the standard position if you can, see if it makes a difference.

CT9s are shit at controlling boost, they are just too small, even the hybrids. An EWG setup and a good EBC and you should be ok though !! But in this cold weather it is normal to get a bit of boost creep / spike.

[toyotag2014]

i cant put the filter back as the port on the hybrid ive got on now is bigger than standard port and wont fit standard filter pipe back on that why ive had to go front filter which i didnt want but had to whats ewg and ebc fella ?

[Gainzy]

Wondering if anyone else has issues with boost creep?

My EP91 is running the stock turbo, Japspeed cat back, HDI front mount & air filter relocation

I have recently fitted a hks actuator and set it to .7 to start with. On the first test run, the car would boost fine to .7 then in the higher revs it would shoot up to almost 1 bar then hit boost cut.

I have now set the actuator back to stock boost and it still overboosts and hits cut in most gears. This is driving me mad!

Can anything be done to stop this?

I have read into setting the piping so that you can still use the hi-low solenoid with the hks actuator. Would this help?

Put your stock actuator back on it has a weaker spring than the hks that should help

[daniel_g]

i cant put the filter back as the port on the hybrid ive got on now is bigger than standard port and wont fit standard filter pipe back on that why ive had to go front filter which i didnt want but had to whats ewg and ebc fella ?

Ahh i get ya. And external wastegate and electronic boost controller.

[toyotag2014]

see thats my problem i want to try keep the car as standard as possible and not get all of that is their no over way around this ? thanks for your help aswell fella

[Ollieh17]

Put your stock actuator back on it has a weaker spring than the hks that should help

Hmmm debatable,stock actuator spring is usually worn so slower to open and shut the wastegate.

[mikey4410]

as above the ct9 are shite with boost regulation. making wastegate bigger or porting it wont do much at all.

save yourself some agro and just go external.

they regulate boost absolutely bang on each and everytime. cant recommend it enough.

superb bits of kit even on a cheap budget external wastegate also.

go external and you will be soooo impressed

[Ollieh17]

How confident are you working on the car? If you are take the turbo off, and using a dremel port the wastegate in a circular motion. These worked wonders for me and held 0.8bar with a hks actuator and all breathing mods

[daniel_g]

see thats my problem i want to try keep the car as standard as possible and not get all of that is their no over way around this ? thanks for your help aswell fella

If you dont really wanna go down the 'buying hundreds of mods' route lol, then either restrict the air intake or the exhaust, this will stop the engine breathing as freely, but will also stop it overboosting. Beat bet for you is an exhaust bung.

[toyotag2014]

klkl lol ill have to buy them then but hide the boost controller or something and get a decent ewg what brands would you say fella ?

[mikey4410]

I run a zisco external ct9 with a cheap 50 quid external and thats on a hybrid ct9.

runs absolutely perfectly at a bar and never ever deviates in any circumstances.

fit it all, set it up, and forget........

enjoy the car lol

[daniel_g]

klkl lol ill have to buy them then but hide the boost controller or something and get a decent ewg what brands would you say fella ?

For EWG people swear by Tial and Turbosmart. Not gonna lie i have a 60 quid ebay job lol. Will eventually upgrade to a better one but just needed a cheap one to get the car up and running. Isnt on the road yet so no iisues there. Wouldnt run one permanently.

As for EBC i had an Apexi AVCR on my old GT and it was the fuckin business, other people use Greddy, HKS etc. They all do the same thing

[mikey4410]

I run my cheapy external on my daily for 6 months so far and faultless.

[toyotag2014]

klkl guys i will have to have a shop around i thinks thanks guys

[Gainzy]

Plug n play ecu will sort you out for now turbo off could mean buying more gaskets it all depends on what your future plans are for the sake of 5 minutes I would swap the actuator to see if your happy with that I wouldn't be thinking of any boost up without good management it's not worth the risk imo

[fiddlersport]

dont even have a boost gauge (yet) , so dont know if i am getting boost creep lol

was told to get a hks actuator

did you set the preload on the actuator ?

[Gainzy]

dont even have a boost gauge (yet) , so dont know if i am getting boost creep lol

was told to get a hks actuator

did you set the preload on the actuator ?

Boost gauge is a must! I will have a greddy one up for sale soon not in the best condition but at least you can see what boost you will be running.

[federalman]

You can either draw round the internal wastegate flap onto the turbine housing itself and port it so itll flow better, or fully weld roound the flap and get an external wastegate. If youve got a stainless or mild steel manifold already, you can modify it to fit an external wastegate and then get a piece of pipe for a screamer pipe. Personally I'd go for the 38mm Tial MVS v band. They're pricey but will last and if you can to another turbo you can still use it . It'll hold .8 bar all day long or you can use a lower spring and a boost controller.

[Polson2k9]

I have the exact same problem after fitting bigger intercooler. Will a manual boost controller help me? The actuator just stops me boosting in the lower revs but once i get up high it tries to go past 1 bar and fuel cuts :/