crazy boost creep after installing supra smic and dejon tool pipes

ROAD RACE VR-4 · Dec 2, 2003

here is my setup:
small 16g ported to match the ported evoIII manifold with an internal wastegate.
i have ported 95 o2 housing that dumps in the atmosphere.
i have an evo manual boost controller (from inside the car

)
before i installed my supra intercooler and dejon tool pipes i never had boost creep. my mbc used to be connected to the wastegate (which it still is) and the other side to the J pipe coming out of the turbo. now the dejon tool pipes dont have that nipple on it so i could connect the mbc to it, so i tapped into to BOV vacuum line, and i get some nasty boost creep. its set at 10psi but creeps up to 20psi and maybe beyond (but never tried)

bokubob · Dec 2, 2003

That doesn't sound so much like boost creep as your wastegate never seeing the boost at all, and never opening. It seems to me that you have it tapped in the wrong place, and that you really want to tap the J pipe, or one of the other pipes, something that sees more of the boost that your turbo is creating, and the closer to the turbo the better.

bokubob · Dec 2, 2003

I guess, now that I think of it, I've heard of people using the mbc setup like you're using, and it seems to work. But I'm wondering that with your other mods you might need something better. This is where I sit back and see what someone who really knows has to say.

-Jonathan

ROAD RACE VR-4 · Dec 2, 2003

bokubob said:
That doesn't sound so much like boost creep as your wastegate never seeing the boost at all, and never opening. It seems to me that you have it tapped in the wrong place, and that you really want to tap the J pipe, or one of the other pipes, something that sees more of the boost that your turbo is creating, and the closer to the turbo the better.

well the new dejon tool j pipe doesnt have a nipple on it so i cant hook it up there.
i hook it up to the BOV vacuum line. half way between the manifold and the BOV.
what other pipes can i hook it up to? or any other places?

rrk5485 · Dec 2, 2003

I was having this same problem before. I would creep to like 22psi+. Never bothered to see how high it would actually go. But I ported out the wastegate hole on my turbo to the max and now it creeps up to 19psi. BTW I have the same j-pipe from dejon tool without the wategate nipple and I tapped my mbc with the bov vaccume line.

TransAmConvert · Dec 3, 2003

You have almost exactly the same setup as i do, i guess ill weigh in. Are you running the vac lines the whole way into the car and back? That can be part of the problem. I don't think you're making so much exhaust gas that you cant keep the boost below 20 psi. I can't set mine below 18 or it just creeps back up there for that reason, but 22 is too high for that i think. With your dump you should be able to hear the WG opening, it is extremely loud. Mkae sure you are hearing this, otherwise the WG isint totally open. Also make sure the right end of the boost controller is hooked up to the wastegate. Tons of people take their boost source from the bov line including myself, i see no problems there.

ROAD RACE VR-4 · Dec 3, 2003

TransAmConvert said:
You have almost exactly the same setup as i do, i guess ill weigh in. Are you running the vac lines the whole way into the car and back? That can be part of the problem. I don't think you're making so much exhaust gas that you cant keep the boost below 20 psi. I can't set mine below 18 or it just creeps back up there for that reason, but 22 is too high for that i think. With your dump you should be able to hear the WG opening, it is extremely loud. Mkae sure you are hearing this, otherwise the WG isint totally open. Also make sure the right end of the boost controller is hooked up to the wastegate. Tons of people take their boost source from the bov line including myself, i see no problems there.

no the lines are not ran into the car and back. the boost controller is mounted on my ac fan but i can adjust it from inside (its hallman evolution with the cockpit controller). i kept the vacuum lines to a minimum. the one that was hooked up to the wastegate its still there and its short (around 12" or so) and the one going to the BOV is about 18" or so.
i hear the wastegate opening at 10psi but its still making boost.

Enigma_Man · Dec 4, 2003

Well, to eliminate the source of some problems, connect the wastegate directly to a vacuum line (like the one that goes to the BOV).

You should only get ~10 psi, or less (the spring is set to 7 psi, I believe).

If you get more, then either your vacuum line isn't seeing boost, It's kinked, or ripped somewhere; or your wastegate is stuck shut somehow. Make sure that it moves when you apply pressure to it (do an intake leak test).

-Jesse

ROAD RACE VR-4 · Dec 13, 2003

update:
i eliminated the MBC alltogether. first i connected the vacuum line from the waste to the BOV line (tapped into it) and still got the same crazy creep. then i decided to tap into the throttle body (the P port) and still got boost creep.
i dont know what else to do. my car was fine before the dejon tool pipes and supra intercooler. today i noticed something strange. if i revv the motor in neutral the boost gauge will go up to 5psi. is it normal to make boost at idle??

also at the same time i installed the supra intercooler and pipes i did the the emmision system removal (removed the egr valve...etc).
i followed the directions exactly. the ports on the thottle body and underneath the intake manifold are looped together and the the charcoal canister is plugged. the thermal valve is not looped or plugged because its not necessary.
did i do anything wrong? thanks for any replys.

thegreatms · Dec 13, 2003

maybe your boost gauge is messed up. are you sure your makin 20 psi of boost? 5 psi at idle is pretty weird. check the waste gate flapper arm, make sure it can open. remove the acuator and try to rotate the arm. Maybe you wastegate acuator is busted

ROAD RACE VR-4 · Dec 13, 2003

yea the boost gauge is fine. it was fine with the stock 14b and it was fine with the 16g untill right after i installed the pipes and the intercooler. i have an older autometer gauge and that shows the same readings.

91TalonTSi · Dec 13, 2003

Hu???

if i revv the motor in neutral the boost gauge will go up to 5psi. is it normal to make boost at idle??

Sooo...Witch is it ? 5psi @ idle or when you rev the motor ? Idle is when its at or below 1,000 rpm. If it does it with the car just idleing then your guage is whack. I would also check to see if your boost controller isnt backwards.

ROAD RACE VR-4 · Dec 13, 2003

when its in neutral and i revv the motor it goes up to about 5psi.
at idle it shows 18-20 vacuum.
sorry about the missunderstaning on the above post.

91TalonTSi · Dec 13, 2003

damn

If you can get 5psi from reving thats some hella spoolup batman

But @ 5 psi the wastgate is still closed so that doesnt really mean anything. Just that your turbo spools good.

ROAD RACE VR-4 · Jan 11, 2004

yesterday i went to see my mechanic. he deals only with dsm's 7 days a week. he told me that now with the supra intercooler and hard pipes the car is able to push a lot more air and therefore more exhaust gasses are produced and they cant get out in time.....so thats why i have boost creep.
i dont know how this is possible since i have the 34mm flapper, the wastegate area is ported to max, i have a 95 o2 housing thats been ported to hell and its externally dumped. he told me i'll have to get an external waste gate in order to get rid of the creep.
i was wondering if anyone else here that has similar mods to me also have problems with boost creep.
i dont really wanna spend $300-400 on an external gate and still have boost creep.

lithium · Jan 11, 2004

I never had a 16g that didn't creep on my car. 34mm flapper, EVOIII manifold, ported or tubular 02 housings, full 3" turbo back. With the cat on the car, I was able to keep the boost a little under control, but w/ a testpipe on there, I always had to run up to 21 PSI to keep the creep inivisible.

Boost in neutral is possible as well. I've seen up to 13 PSI with a quick rev to redline in neutral on 16gs before... my AGP L2R even makes about 6 PSI in neutral. It all has to do w/ flow and pressure differences. Keep in mind, I also see 20 psi on my L2R before 3500 rpms

TJtsi · Jan 13, 2004

I'm having the same problem but I just installed a sbr frontmount. I don't have time to work on it right now, but I'll post what ever solution I come up with. Let us know what you do to fix yours.

dsm6yrs · Jan 13, 2004

My B16g only creeps to around 16psi when it is below freezing outside.

crazy boost creep after installing supra smic and dejon tool pipes

ROAD RACE VR-4

bokubob

bokubob

ROAD RACE VR-4

rrk5485

TransAmConvert

ROAD RACE VR-4

Enigma_Man

ROAD RACE VR-4

thegreatms

ROAD RACE VR-4

91TalonTSi

ROAD RACE VR-4

91TalonTSi

ROAD RACE VR-4

lithium

TJtsi

dsm6yrs

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