3" turbo back exhaust
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From: NR Reading PA
Originally posted by 1QWKEVO
To correct some... larger piping does not cause boost creep, ........
To correct some... larger piping does not cause boost creep, ........
The laws of thermodynamics not physics rule in this discussion!!
Speedlimit........
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Proper design in regards to wastegate flow will NOT result in boost creep. Cheap poorly designed crap will. Sorry but internally gated turbos arnt going to happily bypass the gate unless something is stopping the flow.
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From: Seattle
Well I can certianly say some things about this thread....
1. I think we have pretty much explained boost creep to the newbies
2. Speedlimit has answered the main concern for new Evo owners out there...There is no creep issues on the Evo.
1. I think we have pretty much explained boost creep to the newbies
2. Speedlimit has answered the main concern for new Evo owners out there...There is no creep issues on the Evo.
Hopefully the info from Burshcur is representitive of all EVO VIII's. As a Syclone owner, I know that replacing the cat with a "test pipe" causes guaranteed boost creep when relying on the stock integrated turbo wastegate. Sy owners typically leave their cats in place until upgrading to an external WG.
From Burschurs comments it sounds like the EVO configuration doesn't suffer from the same kind of boost creep issues. I think using caution through close monitoring of boost is nonetheless a very logical thing to do when making this kind of change. I personally prefer a race cat that continues to provide factory 02 sensor hook-up.
From Burschurs comments it sounds like the EVO configuration doesn't suffer from the same kind of boost creep issues. I think using caution through close monitoring of boost is nonetheless a very logical thing to do when making this kind of change. I personally prefer a race cat that continues to provide factory 02 sensor hook-up.
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From: L.A
I am using the HKS EVC 5, and I had set the target boost to 1.4 bar, ~19-20 psi, and I had notice that under full boost, the targeted boost is reach and then it will fall back like 1.3 bar then 1.4 back and forth under full boost, but never over the 1.4 limit that I set, is it normal?!?! or it should stay steadly at 1.4?! thanks!!
wing
wing
Originally posted by N10S
Hopefully the info from Burshcur is representitive of all EVO VIII's. As a Syclone owner, I know that replacing the cat with a "test pipe" causes guaranteed boost creep when relying on the stock integrated turbo wastegate. Sy owners typically leave their cats in place until upgrading to an external WG.
From Burschurs comments it sounds like the EVO configuration doesn't suffer from the same kind of boost creep issues. I think using caution through close monitoring of boost is nonetheless a very logical thing to do when making this kind of change. I personally prefer a race cat that continues to provide factory 02 sensor hook-up.
Hopefully the info from Burshcur is representitive of all EVO VIII's. As a Syclone owner, I know that replacing the cat with a "test pipe" causes guaranteed boost creep when relying on the stock integrated turbo wastegate. Sy owners typically leave their cats in place until upgrading to an external WG.
From Burschurs comments it sounds like the EVO configuration doesn't suffer from the same kind of boost creep issues. I think using caution through close monitoring of boost is nonetheless a very logical thing to do when making this kind of change. I personally prefer a race cat that continues to provide factory 02 sensor hook-up.
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From: Turkey Town (Gobble-Gobble)
speedlimit, explain open wastegates to me then...... in theory this is the same thing as large exhausts (mainly referring to the wastegates and flow), boths main goal is to yield the highest amount of flow. I'm not trying to say adding an exhaust won't create boost creep i'm saying if it is there then another factor is causeing it. Another problem with boost creep on a majority of cars is the poor choice of boost controllers, some units cannot hold boost sufficent do to poor valve design. But i guess this means nothing becasue boost creep isn't an issue on the evo as someone stated before.
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From: Seattle
You did say addind a larger pipe (I'm assuming exhaust) does not cause boost creep but spikes. 
It is true that MBC's can cause creep. At the same time the lower model EBC's can't do anything to stop it either..the newer ones with fuzzy logic I have learned can combat this by adjusting themselves because they can actually "see" what the boost really is. Simply put boost creep is just being caused by not ENOUGH gasses gettting out of the housing, so boost builds cuz the wastegate cant get rid of enough even tho it is open. That is why porting is the best way to completely eliminate it or by going with an external gate. I believe but maybe wrong..by adding a larger exhaust it is less restrictive than the previous set-up....if it is too free, to say, the wastegate cant keep up with the new exhaust's flow. So before when the exhaust was a restriction now the restriction would be your wastgate hole . Is this a good hypothesis speedlimit? You seem to be up to par!
It is true that MBC's can cause creep. At the same time the lower model EBC's can't do anything to stop it either..the newer ones with fuzzy logic I have learned can combat this by adjusting themselves because they can actually "see" what the boost really is. Simply put boost creep is just being caused by not ENOUGH gasses gettting out of the housing, so boost builds cuz the wastegate cant get rid of enough even tho it is open. That is why porting is the best way to completely eliminate it or by going with an external gate. I believe but maybe wrong..by adding a larger exhaust it is less restrictive than the previous set-up....if it is too free, to say, the wastegate cant keep up with the new exhaust's flow. So before when the exhaust was a restriction now the restriction would be your wastgate hole . Is this a good hypothesis speedlimit? You seem to be up to par!Last edited by mobius97; May 2, 2003 at 02:42 PM.
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From: NR Reading PA
Originally posted by 1QWKEVO
speedlimit, explain open wastegates to me then...... in theory this is the same thing as large exhausts (mainly referring to the wastegates and flow), boths main goal is to yield the highest amount of flow. I'm not trying to say adding an exhaust won't create boost creep i'm saying if it is there then another factor is causeing it. Another problem with boost creep on a majority of cars is the poor choice of boost controllers, some units cannot hold boost sufficent do to poor valve design. But i guess this means nothing becasue boost creep isn't an issue on the evo as someone stated before.
speedlimit, explain open wastegates to me then...... in theory this is the same thing as large exhausts (mainly referring to the wastegates and flow), boths main goal is to yield the highest amount of flow. I'm not trying to say adding an exhaust won't create boost creep i'm saying if it is there then another factor is causeing it. Another problem with boost creep on a majority of cars is the poor choice of boost controllers, some units cannot hold boost sufficent do to poor valve design. But i guess this means nothing becasue boost creep isn't an issue on the evo as someone stated before.
From the DSM FAQ's:
Boost creep occurs when the turbo is pushing so much air that the wastegate, even when fully open, cannot dump all of the intake pressure. This results in a continual increase in intake pressure, and is common with upgraded turbos, especially with upgraded downpipes - the exhaust would rather flow through the turbo/exhaust than the more restrictive wastegate, which spins the turbo ever faster. Cars with this problem can develop mind-blowing (and engine-blowing) intake pressures in a hurry. The general solution to this problem is to port the oxygen sensor housing, turbine housing and/or wastegate to allow them to dump more air.
In the EVO's case, the wastegate is very efficient according to Buschur and so far creep is not an issue.
Speedlimit........
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From: Rockville, Maryland
wow, thanks for all the responses...I feel a bit better now... I am doing the HKS EVC V which i hear is a better unit on the maket?...I have also the HKS SSBOV on the way... I guess Im cool then?....
-shahul
-shahul
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From: Buffalo, NY
Ultimate Racing 3" Turbo-Back gets my vote!
I installed mine this past weekend and it's SWEET! Especially since it doesn't cause that stupid CEL to turn on! I'm thoroughly impressed with the quality of the exhaust. Sounds good while driving...not loud and obnoxious like all the other ricers out there. sounds like a deep rumble...but quiet.
now all i need is a boost controller. was thinking about the greddy profec e-01.
I installed mine this past weekend and it's SWEET! Especially since it doesn't cause that stupid CEL to turn on! I'm thoroughly impressed with the quality of the exhaust. Sounds good while driving...not loud and obnoxious like all the other ricers out there. sounds like a deep rumble...but quiet.
now all i need is a boost controller. was thinking about the greddy profec e-01.
I'd recommend the Ultimate Racing 3" turbo back exhaust also. I installed it onto my Evo this week. It's a lot quieter than I thought it would, being that it's a 3" exhaust. Sounds nothing like a typical 3" on DSM. The exhaust has a tone, but definitely not loud at all. Sounds good from the outside too. The fit and finish is excellent. The 3" downpipe clears the 2 stock lower tie bars. Also, no check engine light even with their test pipe
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From: Rockville, Maryland
you say you arent getting a CEL and you have the turbo back and the HKS SS BOV?... I have a custom K&N intake and the HKS bov and I get a CEL... hmmm...
I think Im getting the Ultimate racing exhaust 3" turbo back
-Shahul
I think Im getting the Ultimate racing exhaust 3" turbo back
-Shahul
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From: Buffalo, NY
Shahul X...i say go for it!
No CEL! They have a little trick for the o2 sensor and it doesn't involve any electronics either! That is what impressed me. But they told me to try and keep their method a secret as they didn't want anyone to copy it...so i will do them that favor.
Plus i believe i saw their post that they are shipping for free right now. so you might want to ask about that.
No CEL! They have a little trick for the o2 sensor and it doesn't involve any electronics either! That is what impressed me. But they told me to try and keep their method a secret as they didn't want anyone to copy it...so i will do them that favor.
Plus i believe i saw their post that they are shipping for free right now. so you might want to ask about that.