True 3" turbo back...need to know

[Eclipse96Ryder]

ok so i have been hearing a lot about 3" turbo back exhausts. I plan on doing this but some people have said thered mad boost creep and some have been saying only do it if you upgrade the o2 sensor housing...and some people have gotten that o2 eliminator downpipe.

so im really looking at the RNR o2 eliminator downpipe...3" test pipe, and a 3"cat back (apexi or custom). so when i eliminate the o2 sensor...i dont really get what happens. dont u need the o2 sensor? am i completely missing something here? im almost dont with all the stage 1 mods, i just need my full exhaust but im totally confused on which route to go. Doesnt the Apexi downpipe eliminate the cat? if i got the apex downpipe would it be recommended to buy a bigger o2 sensor housing? , sorry about all the questions, just trying to get my facts straight before i buy something that I will regret...just like i did with my non turbo eclipse, HAHA

 

[JessesTalon]

yes you will get mad boost creep like me and cant WOT past 5k rpm's

5k rpm's its at 15psi all of a sudden from my MBC being set at 10...

anyways def get a ported o2 housing or elimnator (i suggest the cheaper way) so just get the stock 2g mani ported...
def upgrade your BOV because when u get the exhaust boost creep will be above 12psi at 4k rpm's or less...

 

[heavyD]

If you have a good electronic boost controller it won't be a big deal. If you have a manual boost controller, you may want to upgrade it to an electronic. I have a full 3" exhaust and haven't had any problems.

 

[JessesTalon]

Originally posted by heavyD
If you have a good electronic boost controller it won't be a big deal. If you have a manual boost controller, you may want to upgrade it to an electronic. I have a full 3" exhaust and haven't had any problems.

on ur stock turbo/o2/mani?

 

[joeym4130]

I have always heard and am pretty sure that any type of boost control is NOT a way to cure boost creep.. I think in some mild cases it can help, but the problem is the way the exhaust gases are flowing with the wastegate. A bigger wastegate/o2 housing is a cure i know...hopefully somone will jump in....

 

[JessesTalon]

Originally posted by joeym4130
I have always heard and am pretty sure that any type of boost control is NOT a way to cure boost creep.. I think in some mild cases it can help, but the problem is the way the exhaust gases are flowing with the wastegate. A bigger wastegate/o2 housing is a cure i know...hopefully somone will jump in....

yes exactly, hence the reason i said port the o2 and exhaust mani...
which im getting done this weekend, yeah no more boost creep!

 

[eclipse90gsxt]

I have a full Turbo Back 3 inch exhaust. I have a ported 02 housing with a 02 dump, and I have my mbc @20lbs on my big16G which is also ported and I get no boost Creep at all.

 

[91TSi FWD]

Originally posted by JessesTalon
yes you will get mad boost creep like me and cant WOT past 5k rpm's

5k rpm's its at 15psi all of a sudden from my MBC being set at 10...

You will not DEFINATLY get boost creep. It seems that it only happens to some people. I have a 2.5" downpipe, 2.5" cat-back a removed cat, and a stock/non ported O2 housing and have no problem with boost creep. Sometimes why boost creep happens is not becuase of the O2 sensor housing beiing restrictive, but has to do with the acctuator not beiing able to open up the wastgate fast/full enough when set boost is reached.

 

[91TSi FWD]

Originally posted by JessesTalon
yes exactly, hence the reason i said port the o2 and exhaust mani...
which im getting done this weekend, yeah no more boost creep!

Just get a 2G manifold and leave it unported, you can just polish it. The 2G manifold is great for a 13g, 14b, and 16g set at 17psi or less. If ported too much you will not get good exhaust pulses going through the runners and will not build boost as quickly. Also, some people say to completly port out the area where the runners come together right before the turbo inlet, do not do this! It can lead to exhaust pulses interfering with each other and will not be pionted directly into the turbo inlet.

 

[Colossus]

I've got the RNR 3" Turbo back (sounds great) stock o2 housing stock turbo stock manifold, no boost controller, and I set comfortably at 11 psi.

 

[JessesTalon]

Originally posted by Colossus
I've got the RNR 3" Turbo back (sounds great) stock o2 housing stock turbo stock manifold, no boost controller, and I set comfortably at 11 psi.

really! your lucky, punk, hehehe I wish I could sit comfortably at 15 psi...
( OH BTW u wont see the boost creep with your stock clutch, is that what u have?

 

[98RedGs]

Originally posted by JessesTalon
really! your lucky, punk, hehehe I wish I could sit comfortably at 15 psi...
( OH BTW u wont see the boost creep with your stock clutch, is that what u have?

2nd gens may be way different. But I'm running a hallman mbc, 3inch o2 elim turboback exhaust, stock turbo and unported manifold and I'm not creeping at all.






P.S. I don't think him being on a stock clutch has anything to do with boost creep.

 

[boostedinaz]

I dont want to hijack but just bought an RNR 3inch O2 elim back exhaust. I put it on and and t fits great. My only problem is I get some creep with it. I am still on the 14b for now until I get injectors then I can safely put my 20G on. I am wondering if it is just something I will have to deal with for now or if I can fix it. I dont want to pull the turbo becasue I will be doing that to put the 20G on and dont want to do it twice. I am guessing that the flapper and hole are the big restriction now as opposed to the exhaust and that why it creeps. Any suggestions would be great. Here is a pic of my O2

Michael

 

[midnght]

I run a 3" O2 elim. all the way with a ported evo on a 20g and get no boost creep. That was even with the stock clutch

 

[Mo-Bo0st]

Originally posted by boostedinaz
I dont want to hijack but just bought an RNR 3inch O2 elim back exhaust. I put it on and and t fits great. My only problem is I get some creep with it.

Michael

SOME??? You are crazy. I wouldnt call spiking from 13lbs to 16lbs then creeping to 20lbs SOME.

 

[BOBS90TURBO]

What does the clutch have to do with boost creep, is this a joke

 

[Omega]

I run a ported: manifold, turbo (16G) and a 3" exhaust from the turbo to the tips.

I can hold 10 PSI until 4.5K by 7K I am at 22 PSI.

I know for a fact that the less restricted the exhaust is (same wastegate size) you WILL creep. I am on version 5 of my RNR exhaust (different mufflers/resonators and such). It would appear Ryan found that his 3" exhaust systems would creep. My O2 eliminator does not have the same size wastegate pipe as boostedinaz... it's smaller. Ryan has tried to increase the flow from the wastegate.

I was able to hold 18 PSI at max RPM's with an additional full size muffler in the middle of the car. When I took that out and replaced it with a resonator it would then creep to 24 PSI. Now with 2 resonators (one perforated core and the other louvered) I can hold 22 PSI. Now. I know I can do this with in the cold weather, but once summer hits i KNOW i will be detonating like crazy.

I am very close to just going external dump. But that would force me to hack in to the RNR O2 elim. :thumbdown: If I am going to do that, I might as well go 20G.

 

[Mr. Talon]

dump the waste-gate externally, awesome sound, and hey, no creep. ( i would also port the wastegate outlet to help too.

 

[Omega]

What do you suggest for those of use that DON'T want attention and would like to pass emissions?

 

[ProjectTwin]

I run a T28 and 3" O2 eliminator with an HKS standard wastegate (11.5lb spring), and from there it's a full 3" Thermal catless exhaust...

Don't have a Profec B II yet, and I have NO boost creep.

 

[RnR Racing]

The 02 elim gets rid of the stock cast 02 housing, but still has a spot for the 02 sensor.




We are now using larger wastegate passages for better boost control. Some people creep a little with it, but it is enver anything that is going to kill your. Creeping a few pounds in most cases is fine.


Also we will be soon changing the way we build systems. We are going to be moving to full Stainless steel downpipes and turbo backs. This will insure the parts look better, last longer and are much lighter.

 

[boostedinaz]

Ryan, I was wondering if the pic above of my O2 elim is the one with the bigger WG tube. I know it is bigger than some but are you now upgrading to bigger than the one I have? I am getting a good amount a creep with my setup. I am still running the 14B for now unttil my inj. comes. Any imput would help.

Michael

 

[RnR Racing]

Actually that is the bigger wastegate passage. With some stock turbos you will get 3-4psi of creep. You need to port the wastegate passgage of the turbo or upgrade to a 38mm flapper.



If we put a bigger pipe on there then you would get reverse creep where the boost would fall off at high rpm's.

 

[boostedinaz]

Thanks you sir.

Michael