Boost Creep

[13thracer]

yeah sonunds like the most logical answer to me, wish me luck,ill go get a decent dump pipe.

[13thracer]

pulled that old dump pipe off tonight was going to chop and weld a bigger wastegate pipe on that was until i noticed the big crack forming around the wastegate pipe weld, i reckon i had about a week left before it blew itself off. moral of the story dont buy any hks copy dump pipes off ebay. i could still use it with some fresh welding and new pipe but the BATMBL is on its way . will see how that goes.

[dezz]

You've read my thread so you know basically what my problem is..

for the record, i have the batmbl split dump pipe....

[Tragic]

I have exactly the same problem R33 with a Greddy E-01 and a genie dump pipe. Even with the EBC off boost still creeps up to 10+ psi

I gave powerplay imports a call thinking it was the EBC causing the issue but they believed it was just a leak, told me to book it in and they shouldn't have any issues fixing it.

I havn't booked it in yet but will let you know how it goes when I do

[J_Red33]

I've got this kind of problem too. My dump gets swapped over tomorrow as the wastegate pipe on mine is cracked, nearly stalls too due to lack of back pressure when u give it a quick rev in neutral & when taking off. I'll let everyone know how it goes.

I've also got a ball & spring control valve so that may be the cause of it yet. Need to get a deacent EBC too.

[J_Red33]

Had the dump fitted today & the boost went into the stratosphere. Hit boost cut on only part throttle. Turned the boost adjuster down but still got to 13 pound.

Going to have to convert it back to the standard bleed valve tomorrow & see how it goes from there. It was worth noting though that the spiking has settled down which was kinda interesting. Have only driven it for about 20 kays so far (& only half of that once the boost was turned down), but it does seem smoother.

[13thracer]

after cuttiing up my ebay pipe i cant see how it was flowing at all. the wastegate pipe was so restrictive were it plumbed back in it had a huge ridge for the gas to hit very poor quality all round dont buy them people they are 100% shit

[T04GTR]

your wastgate isnt up for it. its needs to be bigger. end of story

[R31 POWER]

Looks nasty but does the job

And yeah 13thracer the pipe is way to small!

[ellie]

Also what size fitting did you weld to the intercooler piping?

Might be slightly smaller than factory or when you welded it on there might be some restriction in it?

Maybe check and bore it out because if there is any restriction it would cause higher than standard boost!

[cameron]

If the new dump pipe doesnt fix it then you still got the same proble we do...

Tried dumping exhaust at end of dump pipe, did have a split wastegate on it and got rid of that and made a custom one, still no different.

Thought their was somthing wrong with the standard turbo, got a new hks one which came with hks actuator. Still creeps!

The hose to the actuator comes from the compressor housing, also tried from the plenum...

[13thracer]

cameron are you running cams in your engine

[J_Red33]

Well I fixed my boost creap. Reconnected the standard boost solonoid yesterday & now I get an absolute max of 9 pound when wringing it's neck. Much smoother, just not terribly torquey in the mid range with the dual stage boost setup. High mode conversion or EBC coming up for me. Unfortunantely it doesn't help you guys.

I take it you guys are running FMIC's as well? I've also got a friend with an S14 who's experiencing similar issues since he put a Trust front mount on his. His solution (though not really fixing the problem) was to fit a baffle in the exhaust to prevent the turbo spooling so hard. Sounds like a wastegate air flow issue to me too, what kind of RWKW's are you guys making?

Edited September 17, 2006 by JazzaR33

[13thracer]

very interesting jazza i may have to get my hands on a standard solenoid i dont have one as the motor is in an s13 now, not sure on the the RWKWs it puts out havent gotten the SAFC tuned and dynoed yet but with the mods i have (see first post) i wouldnt be expecting much over 200 if that, oh yeah and i do have a FMIC too

[J_Red33]

I'll be surprised if it helps you to be honest. If you couldn't keep the boost down directly connecting the actuator without any boost controller, fitting the solonoid isn't going to do jack I'm sorry to say.

It really does sound to me like your wastegate just can't flow enough air. 200 RWKW doesn't sound too much, but then my friend is having similar issues on his S14 with a little less power. Similar size turbo too.

[13thracer]

well the standard solenoid went on tonight went for a drive and well im just as suprised as everyone else will be it holds 7psi to 4500rpm clicks over and then only spikes to about 11psi then settles at about ten pound i still hit a small amout of rich and retard along the way i think due to the cams but still held ten all the way to 6500 rpm in third at full throttle. 2nd gear is abit more harsher and hits rich and retard with a spike of about 12 or 13 psi but keep in mind, i am running the stock dump pipe again, no spliter no bellmouth just the stocka i have the BATMBL on its way so hopefully it should clean up the rest of the small spike but either way it doesnt continually creep up like it used to

[J_Red33]

Yeah it won't creap with the stock dump, that thing is sooo restrictive.

My new dump is a BATMBL one also, but it's still not going higher than about 9 psi when I push it all the way to the limiter (2nd or 3rd gear). I'm only going by the stock gauge mind you, but the power delivery is much smoother without any spike what so ever by seat of the pants. I could always tell with the ball & spring controller if it spiked.

I don't have a FMIC like you either though so that could be the difference. Hopefully the new dump flows the wastegate better.