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

[kenamond]

All those little porting slivers suck!

Use double-cut or diamond cut burrs. The cuttings are more like itsy-bitsy logs than needles. They give you a rougher finish, but an 80 grit flapper wheel on a Dremel tool will smooth out that rough finish in no time. When I ported, I had one single-cut flame burr and one double-cut cylindrical-ball-end burr. I agree - the single cut burr made some NASTY slivers!

 

[kenamond]

Can you post a picture of the MBC? Even a picture from the vendor would be helpful.

If it won't boost past 12psi, that's not creep. The lowest you'll be able to go is about 9psi on a 2g (not sure on a 1g - it depends on the WGA on your turbo). But it'll probably be in that ballpark. That's what you'd get if you ran a vaccuum line straight from the j-pipe to the WGA. If the MBC is unable to increase boost, that tells me that it's either a very weak spring (not holding the valve closed very hard) or the internal valve isn't sealing. You might try taking it apart again and making sure everything is aligned correctly.

If you have a pressure tester, you can apply pressure to the nipple that goes to the j-pipe (but apply pressure to the MBC, not the j-pipe) and find out what pressure it starts to leak at. If you add 9psi or so to this number, that is roughly the boost you should see. If you get 3psi with it all the way tight, that might explain why you're getting 12psi boost.

And you can always try to contact the MBC vendor and tell them your problem.

Another option is to get a different MBC. My Joe P IL was like $50 and works like a charm. There are many others out there that work well, but there are probably just as many that don't work well.

Finally, can you see a small hole in the body of the MBC somewhere? All ball/spring MBCs need this bleeder (I explained why several posts ago I think). If the vendor doesn't know enough about MBCs, it may not have been included. That's a long-shot, though; I would guess that someone selling MBCs would know enough about them. But they are actually a lot more complicated than they seem at first glance, so who knows.

 

[90tsidude]

ok thank you all for your posts. i don't have a MBC, im running the WGA straight to a boost source. I have no cat. i have a test pipe and with the evo3 o2 housing it is 2.5 all the way back. i really don't want to port the turbo as it is brand new and if for some reason it does fail i have the 1 year warranty on it and i really don't want to spend another 600 bucks on a turbo. yes as one of you said, i hit 4k and it starts creeping. it will hold 10-12 till 4k then creep up to 17. im still running the stock 1g mani. i was going to upgrade to the evo3 mani when i got some more cash. i was going to put my stock muffler back on as im being hassled by local cops would that help at all. i guess i can port the o2 hosing, what all would i need? a carbide bit? where would i get one, i looked at home depot and came up short all i found was grinding stones and they barely work on aluminum.

 

[dsm-onster]

Or you could rewire your fuel pump, score some cheap 550s and an SAFC from ebay, and enjoy the boost . An evo3 16g can handle 17 psi all day long on a stock longblock. Your IC may heat soak. It depends on how many times in a row you do a hard pull .

 

[kenamond]

ok thank you all for your posts. i don't have a MBC, im running the WGA straight to a boost source. I have no cat. i have a test pipe and with the evo3 o2 housing it is 2.5 all the way back. i really don't want to port the turbo as it is brand new and if for some reason it does fail i have the 1 year warranty on it and i really don't want to spend another 600 bucks on a turbo. yes as one of you said, i hit 4k and it starts creeping. it will hold 10-12 till 4k then creep up to 17. im still running the stock 1g mani. i was going to upgrade to the evo3 mani when i got some more cash. i was going to put my stock muffler back on as im being hassled by local cops would that help at all. i guess i can port the o2 hosing, what all would i need? a carbide bit? where would i get one, i looked at home depot and came up short all i found was grinding stones and they barely work on aluminum.

There are plenty of threads on porting, but if you have an air compressor, pick up a pneumatic die grinder from Home Depot (~$20) and order some carbide burrs online (find out more about which type to get by searching porting threads or PM-ing me). If you don't have a compressor, buy an electric die grinder on line from Harbor Freight or similar ($47 for mine). If you have a dremel tool, get a few flapper wheel bits.

Don't know what to say about the warranty. Maybe you can contact the vendor and A) tell them this turbo creeps on many DSMs with free-flowing exhausts and that they should warn their customers and B) that you'd like to port it without voiding your warranty. Maybe they'll take (A) into consideration before answering (B).

 

[nfernotalon]

Its a Turbonetics MBC im sure they have some idea of what theyre doing, ihope.

 

[nfernotalon]

Here it is apart

 

[nfernotalon]

As soon as I hook it back up it starts creeping I dont get it.. I done see anyting physically wrong with it either, I bough in July so its new..

 

[kenamond]

Okay, I did some searching around, and I don't think that this is going to work for you. This boost controller is for a dual-port wastegate actuator. Our WGAs are single-port. The WGA has an internal diaphragm, a spring, and an actuator arm. The "can" gets pressurized, pushes on the diaphragm which is connected to the arm. The spring holds the arm into the WGA so that the WG flapper is held closed. As pressure on the diaphragm increases, it eventually overpowers the spring and starts moving the actuator arm. On our single port WGAs, there is just a nipple on one side of the diaphragm (on the can, so it applies pressure to the side of the diaphragm opposite the spring-side). There is a small hole on the other side of the diaphragm to let in outside air and let out air when the diaphragm moves. So the diaphragm has boost pressure on one side and normal ambient pressure on the other (because that little hole lets air in and out freely). A dual-port WGA has a 2nd nipple instead of that little hole on the spring-side of the WGA diaphragm. So instead of boost on one side and ambient pressure on the other side, you can apply boost pressure to one side and also provide some other pressure to the back-side nipple (usually some fraction of the boost pressure). If you can make the back-side pressure higher than ambient, it helps the spring out so that you need even more pressure on the other side (boost) to move the diaphragm. That's what your MBC (called a VBC by Turbonetics) is designed to do; it lets you control what fraction of the boost gets applied to that 2nd nipple and therefore to the back-side of the diaphragm in the WGA.

If my educated guess is correct, you connect the VBC as follows: Put a "T" fitting on a vaccuum line running from the compressor outlet to the first WGA nipple. Run a line from the T to the VBC and another from the VBC to the 2nd WGA nipple. Setting the VBC to its lowest setting will block all flow to the 2nd nipple, so that the 2nd WGA nipple doesn't get anything additional, and the back-side gets ambient air pressure (nothing to help the spring hold the diaphragm in place). If you turn it up, it starts letting part of the boost through to the 2nd nipple, and this increased pressure helps the spring hold the diaphragm in place, and it takes more boost to open the WG. Maybe it can be made to work by hooking it up like a normal MBC and then *turning up the boost knob*. That's because "up" on this VBC lets more boost pressure through, but in your case, that would be "turning down" the boost (the more boost pressure you let get to the WGA, the lower boost you'll run).

I'm not sure if it can be made to work in your car, but it might just be the wrong part.

Sorry!

 

[SethA]

Yes, Mr Peepers more-flapper-throw actuator worked for me. You can go through the thread an do it yourself if you're a decent welder and up for the work: Evo3 16g Boost Creep-Solved?.

But, I recommend giving him a pm if you have a creep problem that goes away when disconnecting the actuator. I believe kenamond. It most likely will be remedied by a longer throw actuator (a more open flapper). And he does good work. You'll get nifty adjustable wastegate actuation out of it all, too.

Great thread. Thanks.

Seth

 

[nfernotalon]

Oh man! So basically its not gonna work for my set up right? Why havent I heard anything about this type of MBC anywhere? Maybe you could put up a thread about my situtation and the type of boost controllers, Im not sure whats going on yet so I dont have the info, but I am gonna research this.

I dont think Turbonetics put up clear enough info on this because the shop that installed it didnt mention anything either and im sure they would have... so if i install a regular ball and spring MBC it should work right? So why way before the boost creep i would turn it up even all the way and wouldnt go past 12psi?? is it because of the same reason?

Thanks so much for your help Kenamond and sorry for taking forever on this thread but we both learned something and I think everyone else will too.. Thanks again! I will let you know if it works with a regular MBC..

 

[dsm-onster]

Matt (Mr Peepers) posted it up first .

 

[kenamond]

Mr Peepers needs to contact one of the big DSM vendors and see if they have any contacts that could manufacture these WGAs (and be compensated for it).

And the Peepers mod won't solve boost creep if the turbo still creeps even with the actuator arm removed. I think folks should do that WGA test before trying the modified WGA. They'd have to port, and maybe that'd fix the problem. If WG porting alone didn't, I'd guess that the porting plus Peepers mod *would* fix the problem.

 

[kenamond]

I'm still confused about the whole 12psi vs. creep. You hold 12 psi up to a certain rpm and then it starts going up after that? Anyway, if connecting the vaccuum line straight from the compressor outlet or j-pipe to the WGA gives you 9psi, that means it's the MBC...period.

I went to a couple of sites including the Turbonetics site, and everything I found said that it only worked for a 2-port WGA. At first, I didn't know what that meant, so I found 1- and 2-port WGAs in their PDF catalog with pictures side by side, and then realized what it was. So I think it would be very likely that a DSM owner might not realize the problem with this VBC and buy it, but at the same time, they explicitly say in the product description that it won't work for us, but not in such a clear way to DSMers who aren't familiar with 2-port WGAs.

You might still try turning the boost knob all the way up and see what happens. If my understanding of the VBC is correct, it *might* work like a bleeder MBC in that case. But it might not, too. Just try it and be careful with your foot on the gas and keep your eye on the boost gauge. Let off the gas if it hits 15psi.

Worst case, sell it on eBay and get a Joe P MBC or similar (I like my black anodized Joe P IL model which is very compact, very high-quality-looking, and works very well). I forget, but it was something like $45.

I like helping folks, and yes I did learn something here. You're welcome.

 

[Calan]

That "Turbonetics" MBC sure looks familiar...I have 4 of them laying in my garage.

Here's where I got mine for $16 and some change:

Grainger Industrial Supply: Regulator,1/8 In 4ZM07

How much did that cost?

 

[kenamond]

That "Turbonetics" MBC sure looks familiar...I have 4 of them laying in my garage.

Here's mine:

Grainger Industrial Supply: Regulator,1/8 In 4ZM07

How much did that cost?

O M G! That's hilarious...and a shame. Turbonetics sells them for $67!!! And another site was selling them for $97. Hmmmm....selling them on eBay as a boost controller at a 4x markup sounds like a pretty good idea. Their mammas didn't raise no fools!


EDIT: But the VBC also comes with the mounting bracket...which is $5.40 at Grainger: Grainger Industrial Supply: Bracket,Mounting 4ZK12 . And the VBC kit includes the vaccuum line, NPT fittings, and T fitting for the vaccuum line...so add another $2-3.

 

[Calan]

EDIT: But the VBC also comes with the mounting bracket...which is $5.40 at Grainger ... And the VBC kit includes the vaccuum line, NPT fittings, and T fitting for the vaccuum line...so add another $2-3.

.. yep.. that definitely makes it worth $90

 

[SethA]

Mr Peepers needs to contact one of the big DSM vendors and see if they have any contacts that could manufacture these WGAs (and be compensated for it).

And the Peepers mod won't solve boost creep if the turbo still creeps even with the actuator arm removed. I think folks should do that WGA test before trying the modified WGA. They'd have to port, and maybe that'd fix the problem. If WG porting alone didn't, I'd guess that the porting plus Peepers mod *would* fix the problem.

Ageed. I ported after I got my 18 psi creeping E316g and got it to 13psi which is acceptable to me. If I had known about the disconnect actuator test and the Mr Peepers mod I would have tried that first. Aside from the porting labor (including disassembly and reassembly), I can't imagine that the sometimes excessive porting necessary to reduce creep enough (with a stock wg system) is any good for overall performance of the turbo.

Seth

 

[kenamond]

Ageed. I ported after I got my 18 psi creeping E316g and got it to 13psi which is acceptable to me. If I had known about the disconnect actuator test and the Mr Peepers mod I would have tried that first. Aside from the porting labor (including disassembly and reassembly), I can't imagine that the sometimes excessive porting necessary to reduce creep enough (with a stock wg system) is any good for overall performance of the turbo.

Seth

I know that there are good and bad ways to port the WG, but I'm not sure what the best way is. I know I was posting to a thread where someone mentioned a specific WG porting technique that some of the pros are using that flow well (efficiently splitting WG and turbine flow) at full boost when the WG is open, but flow well enough (don't disrupt the turbine flow) during spoolup when the WG is closed. That'd be a really good tech article if someone could discuss this and show images of the overall approach.

 

[turboAWDfanatic]

Any confirmation on kenamond's comments about that MBC being made for dual-port WG actuators?

nfernotalon, I'd recommend you simply buy a good ball/spring style MBC. Most people around here praise those as being the better type of MBC.


EDIT: Here's a great link on MBC info: Intro to Boost Control
It starts out with basic turbo 101 info, but click down a few pages and it goes into detail about MBC's. Good luck!

 

[kenamond]

Any confirmation on kenamond's comments about that MBC being made for dual-port WG actuators?

Here is the Turbonetics catalog page for the VBC (scroll down to "Variable Boost Control Regulators"). Note the following statement, "Racegate or factory dual port actuator."

Not too clear. So look at the following:

eBay Motors: Turbonetics Manual Boost Controller Kit VBC MBC Turbo (item 230213627392 end time Jan-23-08 06:21:55 PST)

Look at the image showing the installation instructions. See the picture of the external wastegate (dual port) and how that is connected to the VBC? Our WGAs just don't have that 2nd port (called "vaccuum port" in the instructions) on the back side of the WGA (it's open to atmosphere).

And here's one last Turbonetics page:

Turbonetics Inc. | Home | Products | Boost Controllers | Variable Boost Kit, 10psi

Note, "Dual port actuator only." Pretty clear there.

Also, if you Google "Turbonetics MBC" you'll get atleast 50% hits for posts on turbo car forums where folks can't get it to work on single port WGAs.

 

[Mr Peepers]

*giggles at the Peepers mod*

Yes, I have been suggesting to do the test with the flapper swinging freely before anyone sends theirs in. I've been messing around with ebay 16gs since my buddy is currently running one; horrible boost creep. Even with the flapper disconnected it will creep to ~20 psi at the top of 2nd. I'll try porting it this weekend and see if that alone cures it, otherwise I'll be seeing what Ebay WGA's look like on the inside

 

[nfernotalon]

What I mean by the 12psi Kenamond is that when I installed it back in July or something, I didnt have an after market boost gauge, so the guys at the shop Just told me it was turned all the way down until I got a boost gauge...

So when I did get a boost gauge a month later, I tried turning it up to 15psi, but It wouldnt turn up at all no matter how much I turned the knob it stayed at 12psi, It started creeping or working without me turning the knob when I adjusted my timing for some reason a few months later... and Im here now with a useless MBC

My MBC installed by a shop was 80.00 so thats not bad at all for a genuine Turbonetics part and installed by performance shop... they fully built a 1g AWD to 850hp and was in a magazine, so I trusted with my car but mostly they built some mean Hondas, go figure a honda shop would screw me...

Yes i am gonna go with a regular ball and spring MBC

pfispeed.com

 

[Calan]

My MBC installed by a shop was 80.00 so thats not bad at all for a genuine Turbonetics part and installed by performance shop

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

 

[Calan]

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.