External on manifold or 02 housing

[GSTeclipse]

this is somthing that I should know but I want to double check and make sure before I get into doing this !

I am trying to figure out what the diffrence is with a external wastegate on a exhaust manifold or on the 02 housing the pro's and con's of it ?

Is there a sound diffrence?

Power diffrence?
ect........

Thanks from a idiot

 

[DSMcrazy3]

The external wastegate would really serve no purpose on the o2 housing, by the time it got to it, it would have already passed the turbine, thus producing more spin on it, producing more boost. The idea of the wastegate is to bypass that wheel. Once a certain pressure is reached it opens and lets air out before the turbo so it doesn't not provide any more power to the turbo. Put it on the manifold

 

[92awddsm]

The external wastegate would really serve no purpose on the o2 housing, by the time it got to it, it would have already passed the turbine, thus producing more spin on it, producing more boost. The idea of the wastegate is to bypass that wheel. Once a certain pressure is reached it opens and lets air out before the turbo so it doesn't not provide any more power to the turbo. Put it on the manifold

Do you really understand what you stated in this post?

With an o2 mounted external wg, you would just remove the internal flapper but still use the same port for the external to mount to. You are still dealing with the same restriction as you would with an internal, so creep might still be a problem. In order for an o2 mounted wg function properly, you would still neeed to do a lot of port work on the turbine housing of the turbo.

The manifold mounted wg generally performs better because the exhaust has a more direct route to the wg if it is positioned properly. Generally, that best location for a manifold mounted wg is close to the collector, not off of the #1 runner.

 

[rowlex]

I agree 100% with 92awdsm

The o2 mounted external tends to be a LOT more expensive, where as mounted on the manifold it is not.

GSTEclipse: please atleast look through this: http://www.dsmtuners.com/forums/showthread.php?t=195477

 

[Mackzero]

DSMCrazy3,
FYI there are A LOT of people who mount their wastegates off the O2 housing, and there are MANY internally gated turbos that have absolutely no problem dealing with boost control. Don't get me wrong, an external off the collector is the best way, but honestly does not make as much difference as you would think on most cars.

 

[GSTeclipse]

seems like I am understanding a little .......so putting the external wastegate on the 02 could also result in some boost creep still ?

As for that I am running a rs60 (60-1) from AGP turbo and has the internal wastegate and we can set the boost at 20psi and it will hold 20psi in 2nd gear when we go into 3rd it creeps to 22psi and 3rd will go to 23psi so there for I am wanting to get this under controll to help with tunning on the PLX wideband and get it under controll and the only way I have left to do is external wastegate and I am going to do this off the exhaust manifold !

Thanks alot guy's for the advice

 

[flinguist]

Unless the waste gate passage of a turbo has been ported, it will limit flow to about the same as having an internal gate. So if your going external, and want more flow, mount it on the manifold.

 

[slugsgomoo]

I have an o2 mounted external, and i'm recirculating, so sound isn't a huge deal for me. I do *not* like #1 runner mounted gates, as I don't think they're quite as effective- most of the really high end setups i've seen with the gate on the manifold have the gate coming off of the collector.

I took my turbine housing off, took it to my machinist, and had the wastegate hole opened up all the way. It works quite well, IMO.

 

[99gst_racer]

Repost - This question has already been asked.....

 

[oldman]

seems like I am understanding a little .......so putting the external wastegate on the 02 could also result in some boost creep still ?

As for that I am running a rs60 (60-1) from AGP turbo and has the internal wastegate and we can set the boost at 20psi and it will hold 20psi in 2nd gear when we go into 3rd it creeps to 22psi and 3rd will go to 23psi so there for I am wanting to get this under controll to help with tunning on the PLX wideband and get it under controll and the only way I have left to do is external wastegate and I am going to do this off the exhaust manifold !

Thanks alot guy's for the advice

If you're only creeping 1-2 psi, simple porting of the turbine inlet or raising of the boost level a little will most likely solve your problem without going external, you certainly have enough supporting mods to run 22-23psi.