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Boost creep with dp, intake and SMIC...will it just get worse?

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Old Oct 16, 2002 | 11:28 PM
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Boost creep with dp, intake and SMIC...will it just get worse?

I have been searching for boost creep and it seems that people say it tends to come with cat-back dp,mp intake and upgraded IC...
Well I am creeping to 13psi (in 2nd) with just a dp, apexi power intake, and a upgraded SMIC. (other mods in sig)
I am curious if I will be able to port the wastegate enough to keep this under control...(I don't see why that wouldn't work.) I also have a profec B on the way to assist in controlling the wastegate.
But my next concern is that once I get my new ECU installed I would like to open up the exhaust with a cat-back (I was looking at the Nur-spec). Will my boost creep be uncontrollable?
I don't have a mid pipe and I doin't plan on getting one, maybe a high flow cat, but that wouldn't be any time soon.
I am just trying to plan my mods so I don't have to add a new engine into the list
My option instead of the exhaust would be a new radiator. (for now, I would end up getting the other later).
Thanks for any opinions/words of wisdom or warning/ thoughts
-Dave
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Old Oct 17, 2002 | 03:06 AM
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well....

i'd first test my secondary boost in 3rd or preferably in 4th gear. You can hit secondary boost in 4th without going too fast

As the load increases in the higher gears, you will make more boost or load on the turbos. THus testing boost chacteristics are better off in the higher gears.

I've heard of boost creep in as little mods as just intake, and no boost creep in other cars. I think it reall depends on condition of the car/turbos and if you are lucky or not. My car has IC, intake, full exhaust and no boost creep or spike.

Just try to make your own boost controllers such as the Home Depot one (search) and you should be able to control things more..i hope.

If not, i dont' suggest anymore exhaust mods such as hi-flow or catback, that will only make things worse. Good luck.

Danny
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Old Oct 17, 2002 | 06:29 AM
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It will get worse...time to pull turbos and port the w/g
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Old Oct 17, 2002 | 07:06 AM
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Originally posted by jspecracer7
It will get worse...time to pull turbos and port the w/g
Yea, that was what I was planning on doing. I have heard 5 hours to take apart and port...is that about right? I guess it all depends on how easily eveything comes apart and stuff....
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Old Oct 17, 2002 | 08:33 AM
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I'd make sure you are truly getting creep caused by too much flow for the wastegate before doing anything drastic. You might just have some other boost control problem that appears to be creep, but really isn't.

Boost creep with only your mods would be highly unusual.

Most FD's don't have creep problems as long as there is a main cat converter or a somewhat restrictive catback. In fact, I have yet to see a car personally that breaks this rule.

Bottom line, first determine if you really have creep, because my bet is you don't.

Wade
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Old Oct 17, 2002 | 08:48 AM
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ok, that is what I would have said too...(about not having boost creep with this amount of mods)
How can I determine if it is boost creep?
What else would cause 13psi?

And about doing anything 'too drastic', why would it be bad to port the wastegate and add a profec B? Is that too drastic? If I end up not having boost creep yet, then it would just preventitive measures...right?
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Old Oct 17, 2002 | 08:59 AM
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Originally posted by coop
ok, that is what I would have said too...(about not having boost creep with this amount of mods)
How can I determine if it is boost creep?
What else would cause 13psi?

And about doing anything 'too drastic', why would it be bad to port the wastegate and add a profec B? Is that too drastic? If I end up not having boost creep yet, then it would just preventitive measures...right?
I agree with wade's post up above. If you have a main cat in place I can't see how you're getting boost creep. Hopefully during the Profec B install you'll find some issue with your vacuum hoses and fix the problem. If not, do this: turn the Profec off, which should hold you to 7psi. Redline 3rd gear and observe your boost pattern. When I had a midpipe and ported wastegate, I crept to ~13-14psi. With the main cat in place, you should hold at 7.

Re: the 'drastic' comment: unless you're pulling the motor/turbos for a rebuild, pulling the turbos just to port the WG is a monumental pain in the ***. It's much easier said than done. And if the person porting the WG hasn't done it before, it's very easy to screw up. My bud Steve-o can pull a motor in 2 hours, but we had someone else port the WG because it's so easy to crack it, and then you're screwed.

hope this helps--
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Old Oct 17, 2002 | 09:44 AM
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hummm,.....

Ok, I just tried to figure out my boost pattern...
1st: 2psi
2nd: 10 psi
3rd: spike to 13 psi then 11psi constant
4th: 12 psi constant

What does that mean? Is there a vacum hose pinched?
Is my BOV malfunctioning? I do have the greddy type-s and I don't hear it, (not that I need to) but I had thought the type s was noticable? The stock BOV was louder than this one (it is venting to atm).
I took the BOV apart, it seems to seal and the spring seems to be working (as best I can tell). I adjusted the center pin (soft/hard setting) I couldn't tell any difference...should I put the stock BOV back in?
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Old Oct 17, 2002 | 11:08 AM
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Wade and GoodfellasFD3s sound right to me. You don't have "boost creep", you are just experiencing elevated boost from your mods. BTW, I'm not even sure your boost readings are correct. It appears from your mod list that you still have the stock ecu. The stock ecu will generally not let you boost over 11 psi on the secondary. So if your autometer boost gauge says you are at a constant 12 on the secondary, I would feel confident that it's reading too high (a lot of people with autometers have said they read 1-2 psi too high).

If those are accurate numbers somehow, you need to control your boost to 10 psi with the stock ecu.
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Old Oct 17, 2002 | 11:12 AM
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From: New Mexico
For what it is worth, I also have the boost guage on the Blitz dual turbo timer. It gives me the same readings...Is the blits boost reader just as inaccurate?
How can I get my boost undercontrol with the stock ecu?
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Old Oct 17, 2002 | 02:13 PM
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will putting a silencer help reduce te boost creep?
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Old Oct 17, 2002 | 02:20 PM
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Originally posted by fxxku
will putting a silencer help reduce te boost creep?
If it can add enough restriction in the exhaust. Try seaching for "restriction plates" here in the forum.
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Old Oct 17, 2002 | 02:42 PM
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the way i see it, you are getting more of a spike than creep.

You can't expect to add mods and to have the same boost afterwards. You must adjust accordingly. Get yourself some new boost pills or use the home depot boost control. I personally made a new pill for my pre-control and then i use the home depot valve for the wastegate.

Once you do this, you SHOULD be able to lower boost to as low as 8 psi with your mods...and roughly 10psi with full exhaust.

Danny
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Old Oct 17, 2002 | 03:18 PM
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What Danny said...

Wade
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