Turbo Boost Creep Creeping T25 14B 16G [Merged]

[Mr Peepers]

NOO!!! The dual port WGA was a project I have half complete in my basement... I thought I was the first

I used a guide, valve stem from a bent valve, and valve stem seal to make an airtight seal on the other side of the diaphragm, letting me use some of the boost to keep the flapper from blowing open. My combat to expensive external gates. The secrets out

calan: You're time would be better spent porting the turbine housing rather than the o2 housing. If you still creep after that, let me know. Oh, and let me know the test results and not have to stumble upon them in a misc thread Kidding, but ironic.

EDIT: At least mine is a DSM bolt-on And FREE(for me) You've got to do something with 16 bent valves, right?

 

[kenamond]

Hey Mack... do you have a link handy to one of Bruce's threads on porting the O2? Can't seem to find it anywhere, and looks like I'm gonna have to do some porting.

Disconnected my WGA arm, and at about 5000 I start building boost and it keeps building, up to about 16-17 by redline.

I'll probably try to pick up one of Peeper's actuators also, if he's still making them.

I can't think of any porting info from Bruce w.r.t. the O2 housing other than maybe elaborating on the vfaq article. I really don't think that the O2 housing has very much at all to do with creep. But while you're porting, I'd gasket-match the turbine/O2 and O2/DP while you're at it just to open it all up and get rid of any steps between parts. The vfaq is kind of unclear in the most critical place where they talk about where the exhaust is splattering off the flapper and into the divider and that you should scallop that part of the divider out a bit, but that's still in the turbine housing. So I think that porting the WG entrance in the turbine housing is the most important aspect for creep in your case.

Peepers just posted in one of the other very recent creep-related threads that he was about to tear into some eBay e3b16g WGAs, so it sounds like he's still at it to some degree. Apparently, the eBay knock-offs have big creep problems (don't know if that's any different than legit MHI turbos).

 

[Calan]

Ok... brainfart on my part...

I meant WG in turbine housing. My O2 housing is already ported, but the turbo and mani aren't (they are all 3 MHI EvoIII).

Peepers... I knew you'd be watching this thread too

But yeah.... even with the arm disconnected, I get creep... unless the flapper just isn't blowing all the way open under boost. It moves freely though, and the turbo is only 6 months old.

I could live with it if it would spool nicely and stay within reason (my car is happy with up to around 19-22psi... but it gets finicky in summer or if I get some cheap gas).

EDIT:

I should probably add... I just changed my DP to the correct one from RRE this afternoon, and the creep isn't as bad. My old DP was one from MR that was made for a stock O2, and I had hacked and re-welded it to get it to fit somewhat. I also had a resonator in place, but I removed it when I changed the DP today.

I just pulled my heat shields, lit a smoke, stared at my turbo...and realized I REALLY don't wanna pull that #$%^er off again... damn it

 

[Mr Peepers]

Peepers just posted in one of the other very recent creep-related threads that he was about to tear into some eBay e3b16g WGAs, so it sounds like he's still at it to some degree. Apparently, the eBay knock-offs have big creep problems (don't know if that's any different than legit MHI turbos).

^He might be

From what I've gathered so far:
Ebay WGA's are (all?) adjustable, and have straight arms instead of bent like MHI before they connect to the flapper arm.
They *seem* to have the same throw(very short, ~3/8").
They are not interchangeable with MHI units without modification.

calan:

The test usually indicates the lowest amount of creep on that setup, only changing the WGA. The wastegate passage is the limiting factor in flow so opening the flapper all the way can only do so much. I'll bet that the flapper was opening all the way in the test, and that if you looked under the hood and revved it, you'd see the flapper arm moving.

I would highly recommend porting since it may cure it, and it wouldn't be worth throwing my WGA on for a couple psi less creep. Porting and the "Peepers mod" will compliment each other.

 

[kenamond]

^He might be

From what I've gathered so far:
Ebay WGA's are (all?) adjustable, and have straight arms instead of bent like MHI before they connect to the flapper arm.
They *seem* to have the same throw(very short, ~3/8").
They are not interchangeable with MHI units without modification.

calan:

The test usually indicates the lowest amount of creep on that setup, only changing the WGA. The wastegate passage is the limiting factor in flow so opening the flapper all the way can only do so much. I'll bet that the flapper was opening all the way in the test, and that if you looked under the hood and revved it, you'd see the flapper arm moving.

I would highly recommend porting since it may cure it, and it wouldn't be worth throwing my WGA on for a couple psi less creep. Porting and the "Peepers mod" will compliment each other.

We're seriously digressing/hijacking, but...

I'd be shocked if there wasn't a high-throw, 9-12psi actuator out there that that could be bolted to the compressor housing with a custom bracket and actuator arm extension/mod kit. Seems like a bracket and arm extender would be easier/cheaper than welding two WGAs together ("Peeper Frankenstein WGA").

 

[Calan]

welding two WGAs together ("Peeper Frankenstein WGA").

But it looks DAMN good!

For me, Peeper's WGA is worth the money just to get the nipple in a position that's usable

but since we are talking about boost creep... I wonder how come I got lower creep when I removed the (somewhat) restrictive resonator?

I pulled the arm and tested on my way to a shop to do some welding and fitting the downpipe. On the way home is when I saw less creep... errr... at least it didn't come on nearly as soon and didn't peak as high...although in both cases I never maxed the car to see where it would stop

 

[Mr Peepers]

Cold weather seems to worsen boost creep in my experience. Couldn't tell you why, it was just finicky depending on the weather.

 

[Calan]

In my case, a less restrictive DP (nice clean pipe; not welded and hacked all to crap) and no resonator lowered the creep. The new DP is actually slightly smaller in diameter than the old one for the first 12 inches, but I think it has to flow much better just because of the smoother bends and no weld slag.

That's all that changed, and the two tests were done a couple hours apart. I figured taking the resonator out would actually raise the creep.

EDIT (to save thread length ) :

My engine is at operating temp in 3 minutes... both tests were done after 15-20 minutes of driving.

 

[rrussell]

Make sure you do your testing with the engine at the same temps. Its even a good idea to drive the car around for the same amount of time before you test.

I have always made my MBC for around $18.00. Your typical ball and spring unit with bleeder hole. There rock steady from 8psi to 42psi.

 

[91LaSerTurBo3]

what was your timing set at? mine was set at 5, and it was boost creeping from 13, to 19 PSI, i adjusted the timing on my car( put it back to 0) and that seems to have cured my problem. hope you fix your problem

 

[ricktb]

Just a comment about the MBC as shown above. I use this mbc and it's connected in line between the compressor outlet, and the actuator. When I turn it off (no flow) my boost goes to 14-15psi at max. When I turn it all the way on (max flow), my boost goes down to like 10psi.

I usually have it 2 full turns off closed and I get a 12-13 psi constant, never seem to fluctuate.
Heres a pic of mine

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Oh yea, hey whats up Mr Peepers, remember you helped me with my MBC 10 months ago? I love the advanced drawings we used to explain stuff
http://www.dsmtuners.com/forums/newbie-forum/261630-weird-boost-controller-install.html

 

[Calan]

Still cracks me up that people are selling those as some sort of high tech "MBC"

Especially for the money their asking... sheeeeshhh..

 

[kenamond]

ricktb: In that other thread, you started out with a text drawing of how your boost controller was set up when you first got the car. Then you got a new MBC that looks like the OP's. Is your new boost controller still connected like the text drawing?

If so, then nfernotalon can set his up the same way: bleeder setup. And if he has the stock intake pipe, he can take the hose that was disconnected in your text image and put it where the BCS bleeder line connected to the intake pipe so that he doesn't have a boost leak.

I think I'm understanding this now. nfernotalon had this hooked up like a ball-spring MBC. Instead, he just needs to connect it bleeder-style exactly like ricktb's text drawing but connect the output line of the MBC back to the bottom of the intake pipe instead of leaving it free.

Then he needs to email Turbonetics and recommend that they include bleeder-style MBC setup for single-port WGA use.

 

[Calan]

Ummm.. why is it recommended to drain coolant and oil if you are pulling just the turbine housing for porting?

I just took apart a spare turbo I've had laying around (first time I've been in one), and it looks like I could just leave everything hooked up on the compressor side, remove the 4 mani-turbo bolts, band clamp, and drop the downpipe... and pull the turbine housing/O2.

What am I missing here?

 

[nfernotalon]

Ok ive been playing around with the MBC and its the opposite, the more you turn up the boost on the MBC, the less psi you run. So all the way up on the MBC I get 10psi.. If I turn it to low boost It starts raising it to higher psi its ass backwards.. should I just get a regular ball and spring type or keep it?

 

[nfernotalon]

Not to sound cynical, but that is a $16 part (see my Grainger link), $5 in hardware and maybe 5-10mins work to hook up.... AND.. it's not the right MBC in the first place, which the shop should have known and informed you of.

I wouldn't exactly call that a spectacular deal

Yea every part you buy was made a lot cheaper than sold, if you know someone that doesnt do this and sells theyre stuff for cheaper than they got it, ill buy from them.. let mo know but yea I should of just went cheap on this part, ebay here I come..

 

[Calan]

Get a ball/spring MBC and be done with it.

Put that "turbonetics MBC" on your air compressor where it belongs

 

[nfernotalon]

Get a ball/spring MBC and be done with it.

Put that "turbonetics MBC" on your air compressor where it belongs

Or in the trash

 

[rrussell]

I vote you chuck that thing and go with a ball and spring type much easier to deal with.

 

[nfernotalon]

Check what?^^

 

[rrussell]

Check what?^^

Oh sorry, the turbonetics MBC paint regulator type. I still can't believe they sell them.

 

[nfernotalon]

Yea what a bunch of crap. figures.. I try to buy something decent for my car and this happens its going in the garbage and getting a ball and spring type.. or make one I just need to know what parts to buy..

 

[kenamond]

I think he meant "chuck" rather than "check" as in "throw away".

Did you reconnect it like the post by ricktb (he included a link to another thread where he had text-art showing how he hooked his up)? If you hooked it up that way, and it works, I'd keep it. It cost you a lot, and a ball-spring will cost you more. I know it was a headache, but look at it this way: put that diabolical bastard to work for you!!

If you did hook it up like ricktb's other thread, I'd recommend running the oulet of the VBC back to the port on the bottom of your intake pipe (or whereever the stock BCS bleeder line connects on a 1g intake pipe). Otherwise, this is a boost leak (metered air will leak out of the system at this bleeder). If you connect it back to the intake pipe, it stays in the metered section of the intake and won't cause you to run a bit rich under boost.

 

[Calan]

I need to play around with this (as I have some in the garage)... but the thing that bothers me is that I think you run the risk of air locking the WG. That's one of the reasons the ball/spring types have a small hole in them; to help bleed excess WGA pressure when you cut boost and the ball re-seats.

This Turbonetics MBC is nothing more than a standard air pressure regulator. It will regulate pressure in one direction under constant flow, but I'm not sure it provides a bleed path for reverse pressure with it hooked up the way you guys are talking about. It will reverse flow, but not very well.. at least that's the way the ones I have work.

Thoughts on this Mack?

 

[nfernotalon]

Well I played with the MBC and got it to to stay at 15-16psi im just gonna keep it since I guess its working..