STILL getting boost creep!

[screwdgie]

Well I did a boost leak test last night, and found a few leaks. I fixed them and took the car for a drive today. Well I am still getting mad boost creep. By 3k it will boost to 11 psi, but by 4500 it will creep up to 18 psi. This is really pissing me off, as i am on stock fuel system right now. My dejon mbc has an inline fittingwith a bleeder hole in it. It also came with a fitting with no hole. Should i try the no hole? This fitting goes between the mbc and the wastegate.

Thanks for the help.

 

[CanadianTSi]

Boost Creep has nothing to do with boost leaks.

It has everything to do with how well the wastegate flows. You will probably need to pull the turbo and port the area leading to and around the wastegate so the exhaust gases can flow through it easier.

 

[ericbev]

Boost Creep has nothing to do with boost leaks.

It has everything to do with how well the wastegate flows. You will probably need to pull the turbo and port the area leading to and around the wastegate so the exhaust gases can flow through it easier.

Correct.

Boost creep is caused by the wastegate not being able to bypass enough exhaust gas to keep your target boost level. Since the hole isnt allowing enough air around the turbine wheel, its flowing into the turbine wheel, thus creating more boost (creep).

By porting the inlet, flapper hole (or get a bigger flapper), and the blast zone, you are allowing the gate to bypass more air around the wheel instead of into it. With enough proper porting of these areas you should be able to run the desired boost levels without creep.

Here are a few more general porting links. They should give you a good idea of how its done and what is required.

http://www.vfaq.com/mods/porting-turbo.html
http://www.vfaq.com/mods/porting-exhman.html
http://www.vfaq.com/mods/porting-O2.html
http://www.plymouthlaser.com/trbo932.htm
http://www.dsmtuners.com/forums/showthread.php?t=186525

Hope that helps.

 

[screwdgie]

Ya i thought that leaks had no connection with creeping, yet many ppl have told me it does . This really sucks, because i just had a new exhaust housing installed along with my o2 and dp. I got the housing replaced because the old one was cracked to hell.

I really dont have the time or patience to take it all apart and port it . Thanks for the help though.

Would upgrading to a 7cm exhaust housing help my problem at all?

 

[ericbev]

The exhaust components you installed is what created your problem.

From what I am reading 14psi is about as high as you want to go on a stock fuel system. 18psi and you are asking for trouble. Serious boost creep isnt something you should ignore. My advice to you is to take the time and do the porting.

You could always buy a 190 fuel pump and rewire it for a little buffer zone. But that is more of a bandaid then a true remedy. Last thing you want to do is create a lean condition because of something as easy to fix as boost creep.

If you are plotting on using a 7cm housing, than you have to take everything apart anyways. You wont get something for nothing.

Hope that helps.

 

[screwdgie]

Yea i PMed 2 ppl that are selling the 7cm housing, hope they still have them . I am also planning on getting a 190 anyways.

It doesnt seem too difficult to get the exhaust housing off. Pretty much take the heat shields off, take the band clamp off, unbolt the o2 housing from the downpipe, then pry the housing off the rest of the turbo, and pull it off?

Thanks for the help.

 

[ericbev]

Yea i PMed 2 ppl that are selling the 7cm housing, hope they still have them . I am also planning on getting a 190 anyways.

It doesnt seem too difficult to get the exhaust housing off. Pretty much take the heat shields off, take the band clamp off, unbolt the o2 housing from the downpipe, then pry the housing off the rest of the turbo, and pull it off?

Thanks for the help.

Yeah basically. Unbolt the whole turbo and then remove that sucker. You shouldnt have a problem finding a 7cm housing around here.

 

[keymaster]

No more need for porting folks. http://www.dpconcepts.com

These guys have the answer.

 

[Luckythirteen]

No more need for porting folks. http://www.dpconcepts.com

These guys have the answer.

Anyone think this thing works?
And I wonder what their "kit" has in it that you couldn't find or make at home really easily.

 

[Black94DSM]

No that will not help anything. Whats causing the creep is a back up in flow(through the wastegate hole) not how much the flapper opens. Yes of course if it dont open you will creep also, but our stock setup will open enough already.

They are just trying to make a buck.

Just go in there and port the path to your wastegate hole, and open the hole up as much as you can while still making a good seal for the flapper.

 

[ericbev]

No that will not help anything. Whats causing the creep is a back up in flow(through the wastegate hole) not how much the flapper opens. Yes of course if it dont open you will creep also, but our stock setup will open enough already.

They are just trying to make a buck.

Just go in there and port the path to your wastegate hole, and open the hole up as much as you can while still making a good seal for the flapper.

Correct. The flapper door opens plenty. Porting the inlet, the blast zone, and the actual wastegate hole will yield the results you are after.

 

[Fastbanker]

No more need for porting folks. http://www.dpconcepts.com

These guys have the answer.

I have their kit. It works. But if you have creep like I did (24psi), then don't expect to run 15psi with their kit. Expect about 3-4 psi less boost creep.

 

[GVR4592]

I have their kit. It works. But if you have creep like I did (24psi), then don't expect to run 15psi with their kit. Expect about 3-4 psi less boost creep.

Only 3-4 psi? It is beyond my comprehension why you would pay for something that only brings it down 3-4 psi. Porting is easy, fast, and cheap and will fix boost creep 100%.

Most of the problem is not in the flapper or how far it opens. It's the lip above the flapper that forces exhaust gas to reverse direction and push down on the flapper so it can't stay open. Just by removing that lip boost creep can be almost completely eliminated. Porting the wastegate passage also helps a bit.

Everything you need to know about porting is in the vfaq.

 

[Fastbanker]

Only 3-4 psi? It is beyond my comprehension why you would pay for something that only brings it down 3-4 psi. Porting is easy, fast, and cheap and will fix boost creep 100%.

Most of the problem is not in the flapper or how far it opens. It's the lip above the flapper that forces exhaust gas to reverse direction and push down on the flapper so it can't stay open. Just by removing that lip boost creep can be almost completely eliminated. Porting the wastegate passage also helps a bit.

Everything you need to know about porting is in the vfaq.

For me, it makes perfect sense. Lets see, my other option was to port right?. So first I'd go spend $30-40 in tools. I'd spend an hour to pull the turbo off. About 2- hours porting. Another 1-2 to reinstall everything. Oh plus $10 in replacing water and oil fluids. Also, hope I didn't break a turbo bolt pulling the damn thing off. So lets see, that comes to

$40-50 total
4-5 hours of labor


Now, like I said if I wanted to run 15psi on my evo than, yea I'd be upset, but sense I didn't, I wanted to run about 20psi, I am happy. Why go through more trouble than needed. It is beyond my comprehension why anyone would run 15psi and lower on an evo anyway. So in the end, I paid 30 something dollars, spent less than an hour installing and got just what I needed without spending my whole saturday laboring in the garage trying port stuff. I'll repeat myself one more time, if for whatever reason you have extreme boost creep and want to run 10psi or something, then don't buy this kit. But, if you only need to reduce your creep by a few psi, then their kit is the best bang for the buck IMO.

So back to the original poster's question about creeping to 18psi. If he want's to run 11psi, then I 'd say port, but if he can run 15-16psi, I'd say go for it.

 

[Luckythirteen]

I have their kit. It works. But if you have creep like I did (24psi), then don't expect to run 15psi with their kit. Expect about 3-4 psi less boost creep.

since you have their kit, what is exactly involved with the installation, and is it something you could make at home or do without buying that kit?

 

[SkyLineGtR-R34]

Porting is not that hard at all. I did it few times for my car and few friends' DSMs. Once you do it, and put everything back together, you can be prould of what you've done yourself

 

[Fastbanker]

I had to use a couple of spacers they provided to get the right tension on the wastegate rod, then a sort of c-clip with a pin on it to attach the rod in its new location. A spring and bracket that I guess pulls the gate open further. You could make it yourself with the right tools, but for the cost of parts and trouble of machining, I'd just pay the $30 and have it delivered to my doorstep ready for install.

 

[markGSX]

Adding a cat should help just to restrict flow a little bit.

 

[screwdgie]

Fastbanker, roughly how long did it take you to install this kit? Do you have any pics? Did you have any problems installing the kit? I am interested in buying the kit. I will eventually port my housing, but I just dont see myself having much free time to devote to porting in the near future. If it can drop my boost to 14-16 psi, I should be fine as I will be ordering a 190 fuel pump soon also.

Thanks,
Shane

 

[JessesTalon]

porting my o2 housing didn't do anything when i had my boost set below 14psi...

for whatever reason when i set my boost around 18psi, I never had boost creep again...

I also ported a few o2 housings for people and when we got rid of the center divider in the o2 housing boost creep vanished.

 

[screwdgie]

My mods are in my sig, but with a 190 fuel pump I think i should be ok to run about 16-17 psi on stock injectors. Sound about right? Hopefully my clutch can hold that long enough until I get a new one .

So I am considering buying the dpconcepts boost creep kit and see how it works for me.

 

[screwdgie]

Ok well I went ahead and ordered the DPconcepts boost creep kit and a 190 fuel pump. Hopefully I get them both before this weekend, so i can install them

I'll update everyone as I install everything.

Thanks for the help

 

[Luckythirteen]

any updates yet?

 

[screwdgie]

Well I was expecting my "boost creep kit" today, but it didn't come in. Should be here Monday. Attempted to install my fuel pump this week, but couldnt break that fuel fitting loose, and broke 3 of the 6 studs that hold the cover onto the gas tank . So I'm still trying to figure out what to do.

If all goes well, my creep kit will go on monday night, and the fuel pump probably next weekend.

 

[travislaw]

Well I was expecting my "boost creep kit" today, but it didn't come in. Should be here Monday. Attempted to install my fuel pump this week, but couldnt break that fuel fitting loose, and broke 3 of the 6 studs that hold the cover onto the gas tank . So I'm still trying to figure out what to do.

If all goes well, my creep kit will go on monday night, and the fuel pump probably next weekend.

Here is a little tip, and should work on the GSX's. Instead of trying to break the fuel fitting loose at the fuel pump, follow the line under the car and see where it meets up and connects with the the fuel line. Take it apart there, right under the car, it is a heck of a lot easier.