Wastegate dump tube or running back into downpipe?

[sickandtwisted]

I am putting the T4OB on my car finally. I have a modified SFP manifold (hopefully my braces keep it from cracking) a Turbonetics T4OB turbo and a PIT 40mm wastegate. This car is going to be a drag car with some street use. I welded the wastegate discarge tube back into the downpipe. I know alot of people who drag race run a external dumptube. I think it sounds like a exhaust leak so I ran mine back into the downpipe. My question is is there a housepower incrase by running a external dump? Does running it back into the downpipe backspin the turbo or something? Or is it just easier for people to make a external dumptube rather then cut bend and weld it into the downpipe?If there is a big increase in HP I will weld up another downpipe and exteral dumptube for when I run it.

 

[Black94DSM]

The only disadvantage to rerouting is when you place the reroute tube close to the turbos exhaust blades, or reroute at a 90 degree angle. If you do either of them you will disrupt the exhaust flow and it wont be smooth. You will creat turbulance in the exhaust path.

The right way is to reroute the dump tube further down your downpipe and at a 45 degree angle. Its nice to be able to hear the turbo spool again.. hehe

 

[napkinthief]

I plan on running some side exit pipe for my w/g to avoid major fabrication work and lessen the sound somewhat.

 

[AL92]

I plan on extending mine down under the engine and possibly into the downpipe depending on how loud and annoying it is.I also heard some guys put small mufflers on them which might also be an idea.
Will find out in next month or so when my new shiny FP3065 shows up.

 

[blackGSX2g]

I ran it both ways and prefer to have it dumped back into the downpipe. It was way too loud for me to drive with the windows down and boosting.

I didn't notice any adverse affects in re-routing at a 45* angle at the bottom of my downpipe. It 'felt' a bit slower, but I think it was a placebo as the noise made it seem more uncontrollably fast. DSMLink showed airflow to be the same so I'm sure performance was not hurt.

 

[sickandtwisted]

I ran mine back into the downpipe elbow. It is stight pipe down from the wastegate. I welded the elbow to the downpipe because I had to make a turbo outlet elbow for the turbonetics circle 4 bolt flange. So where it comes out of the turbo and 90 degree I ran the downpipe straight into the top of the elbow. If you looked into the elbow before I welded the downpipe to it it was a straight shot to the downpipe. I figured it was less turbulance running it that way. Not 100% sure if it will work properly or not. I will post a pic of it tomorrow night so you can get a idea on what I am talking about and give me some opinions on if it will work or not. Keep in mind I am running 3 inch from the turbo outlet back. I am using a front facing filter bracket, and usless i relocated the alt I have very limited room to work with. Thanks for all the replys so far.

 

[Slow95gsx]

I didn't notice any adverse affects in re-routing at a 45* angle at the bottom of my downpipe. It 'felt' a bit slower, but I think it was a placebo as the noise made it seem more uncontrollably fast. DSMLink showed airflow to be the same so I'm sure performance was not hurt.

It does make it feel slower, but definetaly has no effect on it. Its good to hear the turbo spool when its recirculated. But then again, its just as fun dumping it and scaring unsuspecting people that are nearby.

 

[VelocitàPaola]

I read about a Nissan 350Z that gained something like 40hp just from converting to an external dump. He was making something like 600hp already, but apparently, the internal dump was making enough turbulence in the exhaust flow that the external made that much of a difference.

 

[Slow95gsx]

I read about a Nissan 350Z that gained something like 40hp just from converting to an external dump. He was making something like 600hp already, but apparently, the internal dump was making enough turbulence in the exhaust flow that the external made that much of a difference.

There is no way there can be any truth to that unless the dump was going the opposite direction of the exhaust flow when it was recirculated.

 

[VelocitàPaola]

I'll dig up the article when I get back home. It was in Import Tuner - I didn't read it on some forum or hear it from a friend of a friend.

 

[240kid]

external dumps are more manly

 

[silversmoke4g63]

i have a big 16g (internally gated) at 17 psi with a wg dumpt o2 housing. under normal driving conditions i dont find my wastegate opens much. if im on an on-ramp or racing, i really enjoy the sound. as far as power increases, the less exhaust gasses you need to pump through your exhaust, the better.

 

[Black94DSM]

i have a big 16g (internally gated) at 17 psi with a wg dumpt o2 housing. under normal driving conditions i dont find my wastegate opens much. if im on an on-ramp or racing, i really enjoy the sound. as far as power increases, the less exhaust gasses you need to pump through your exhaust, the better.

The only time your wastegate opens is when it hits the set PSI level you are running. Thats when it expells the rest of the exhaust gases out the wastegate whole.

 

[silversmoke4g63]

i know. the point i was trying to make is that under normal driving conditions, with my turbo at my preset boost level, the wastegate rarely opens. seems to me it would be less of a concern with a T40B, considering it would take longer to spool than my b16g. i guess driving style is a pretty big variable, though.

 

[dnhieu]

external dumps are more manly

this is completly tru . i dont mind my o2 dump. infact i love the sound of the car as im dumping. everyone who drives next to me says they hear the turbo more then the o2 dump but inside the car all i hear is the o2 dump.....

 

[sickandtwisted]

Sorry I broke my camera had to buy a new one. Here is some pics of my downpipe with wastegate pipe. Let me know what you guys think or should I relocate it.

 

[4wd-Eclipse]

I'm using FP SS 3" O2 housing with FP Green turbo ... the sound is GREAT

 

[aero_sallee]

I'm using FP SS 3" O2 housing with FP Green turbo ... the sound is GREAT

That is a beautiful piece.
I think that would sound alot better than what most people run dumped off the #1 runner. Just loud rather than a loud lawnmower with no exhaust.

 

[compression]

<a href="http://photobucket.com" target="_blank"><img src="http://i48.photobucket.com/albums/f224/mxdawg121/Picture087.jpg" border="0" alt="Image hosting by Photobucket"></a>

this is what im running and it sounds just as mean as yours

 

[VisionPaintball]

compression- Whatkind of o2 housing is that?
Thanks

 

[1glaserturbo]

compression- Whatkind of o2 housing is that?
Thanks

Looks like SSAutochrome....not a bad piece of machinery if you ask me.


Chris

 

[revision27]

i know people have picked up mph after switching to external dump (2-3mph) but that is on cars making over 600whp. i say if you dont like the noise just re-route it. it shouldn't hinder your performance that much

 

[Maglin]

Compressions is the ssautocrome dump. I have one. It requires a lot of porting to get it right for me. And the dump tube is hitting my 3" downpipe enough would I had to do a balony cut of half of the downtube.