Wastegate creep thoughts

[barryogen]

Most people seem to be against wastegate creep, personally, having I prefer it as it puts a bit less stress on things, but that aside...

Now the usual practice to get rid of it, appears to be to buy a boost controller(or whatever, still learning all the turbo terms), so it keeps the wastegate closed until right up to the point that the you hit whatever boost you use.

Being the cheap bastard that I am, I thought about it, and was wondering what would be wrong with making it just "lag" a bit... if you make the wastegate hose longer, or put a small plenum in the path, there would be a lag, induced by the larger area to pressurise, delaying the opening of the wastegate for a bit.

Now obviously this would take a bit of tinkering to get it right, but unless you make it a hugely long pipe, or an overly large plenum, I can't see anything wrong with doing it in this way.

Your thoughts?

[Dell'Orto]

What you'll find happening if you put a longer hose in, or a cannister of sorts into the line is you'll overboost before hitting your set boost pressure.
I don't know why you'd want to delay bringing on boost anyway?

[escortman]

i thought boost creep only happend with the "style" gates etc

[Boosted_162]

i thought boost creep only happend with the "style" gates etc

I imagine it would also happen if you used a 38mm wastegate on a T88!

Couldn't you adjust an EBC to open the wastegate earlier (turn down the gain?)

[matt dunn]

Now the usual practice to get rid of it, appears to be to buy a boost controller(or whatever, still learning all the turbo terms), so it keeps the wastegate closed until right up to the point that the you hit whatever boost you use.

Your thoughts?

My thoughts would be that that is not boost creep.

My thoughts are that boost creep is when the boost rises above the set pressure according to revs?

What you are trying to simulate is the Gain function of an EBC.

Too much gain and you get boost spike.
Too little gain and it's slow to reach the last couple of psi of set boost.

?????

[MasCam]

What you'll find happening if you put a longer hose in, or a cannister of sorts into the line is you'll overboost before hitting your set boost pressure.
I don't know why you'd want to delay bringing on boost anyway?

Probably because he is putting the turbo onto a FF RUNX in which he has traction problems already. I believe he is looking for a smooth power curve rather than having a huge wodge of boost arrive just as you are taking a corner making the car a bit more driveable, rather than chasing the outright most power. And he did mention he is a cheap bastard right??

Would I be right in saying

Boost creep = boost rising above it set value at higher revs due to the wastegate not flowing enough.

Wastegate creep = wastegate starting to open before peak boost is reached delaying full boost

[IH8TEC]

What you'll find happening if you put a longer hose in, or a cannister of sorts into the line is you'll overboost before hitting your set boost pressure.
I don't know why you'd want to delay bringing on boost anyway?

Probably because he is putting the turbo onto a FF RUNX in which he has traction problems already. I believe he is looking for a smooth power curve rather than having a huge wodge of boost arrive just as you are taking a corner making the car a bit more driveable, rather than chasing the outright most power. And he did mention he is a cheap b**tard right??

thats where turbo choice comes into play

[Quint]

Boost creep = boost rising above it set value at higher revs due to the wastegate not flowing enough.

Wastegate creep = wastegate starting to open before peak boost is reached delaying full boost

Thats what i thought too >_<

[matt dunn]

Boost creep = boost rising above it set value at higher revs due to the wastegate not flowing enough.

Wastegate creep = wastegate starting to open before peak boost is reached delaying full boost

I could believe that.

Matt

[barryogen]

was meaning waste-gate not boost creep, like I said, I'm new to this turbo thing, and get confused with all the new terms...

MASCAM was exactly right, FF car, and wanting to keep the car very streetable.

I figure if I can make the boost so it comes on in a smoother fashion, it will mean I will make accidental tyre smoke less of an issue.

[matt dunn]

I figure if I can make the boost so it comes on in a smoother fashion, it will mean I will make accidental tyre smoke less of an issue.

If thats the aim,

if you make the wastegate hose longer, or put a small plenum in the path, there would be a lag, induced by the larger area to pressurise, delaying the opening of the wastegate for a bit.

That would give you the opposite effect,

as to prevent "accidental tyre smoke" you'd want nthe last bit of boost to come on slow wouldn't you?

Matt

[barryogen]

hahaha... I am officially an idiot... but I think I now get it.

ok, well this would suit the guys who are not like me then, and want the big surge of boost...

Originally I posted this mearly as a "I guess you could do this" type post... but the thread turned into a "for my application", which is exactly the opposite of what I actually want.

[barryogen]

heh, I actually found an article on drive.com.au that mentions specifically what I said, and also gives basically the same suggestions.

http://autospeed.drive.com.au/cms/A_1053/article.html