Ok I know that my post could be in the fabrication forum but there is a specific question for the FI guys... at the end.

I will upgrade my DP for a 3 inch soon and I will do it by myself like I did for my exhaust system cuz I couldnt be more pleased than what I did...







Ok I do not have AC and no powersteering. My exhaust is on the side of the tranny on a D16Z6 so I have a lot of space. * I like a clean engine bay lol *

Is there an importance in the curves of the DP like on a NA header ? or I should just take the easiest road to the exhaust ??? Does anyone know if someone did some testing on the design of the DP... I searched but I only found that the bigger is the better...

I will do around 315whp or so on my street tune at 15 psi. My turbo is a SC50 .63ar. so 3 inch is okay for me.

Thanks for the help !

Mat

 

The fewer curves, and the largest curve radius, the better.

 

so basicly the trick would be to get a good flow by using the largest radius curve.

well ok it came to the conclusin of getting the less restriction that you can... like for the size of the tubing.

Anymore idea ?

 

nice exhaust bro damn you got me thinking about trying to do that as well, how long did it take and how much was the material cost?

as for the DP, Beepy the scientist is in agreement with my common sense . At the same time I have heard some things about the bend right after the turbo flange being of some importance..?? obviously I don't know what I'm talking about, but something about that first bend takes out the spiral turbulance from the blade spinning... can anyone chime in to discuss what I'm trying to say? is just HT BS, or do I make a semi point?

just making sure things don't get over looked

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beepy &raquo;</TD></TR><TR><TD CLASS="quote">The fewer curves, and the largest curve radius, the better.</TD></TR></TABLE>

Yup, the best exhaust for turbo is no exhaust, so use the biggest possible piping and least bends.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hawkze_2.3 &raquo;</TD></TR><TR><TD CLASS="quote">

Yup, the best exhaust for turbo is no exhaust, so use the biggest possible piping and least bends.</TD></TR></TABLE>

yep thats true for exhaust, but he's making a DP.. I don't think a turbo will work so well without a DP...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbosi03 &raquo;</TD></TR><TR><TD CLASS="quote"> I don't think a turbo will work so well without a DP...</TD></TR></TABLE>

Ya think?? I consider the downpipe a part of the exhaust as it requires the same consideration as the actual exhaust with a turbo.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbosi03 &raquo;</TD></TR><TR><TD CLASS="quote">

yep thats true for exhaust, but he's making a DP.. I don't think a turbo will work so well without a DP...</TD></TR></TABLE>

yeah thats what I think too...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbosi03 &raquo;</TD></TR><TR><TD CLASS="quote">nice exhaust bro damn you got me thinking about trying to do that as well, how long did it take and how much was the material cost?

as for the DP, Beepy the scientist is in agreement with my common sense . At the same time I have heard some things about the bend right after the turbo flange being of some importance..?? obviously I don't know what I'm talking about, but something about that first bend takes out the spiral turbulance from the blade spinning... can anyone chime in to discuss what I'm trying to say? is just HT BS, or do I make a semi point?

just making sure things don't get over looked </TD></TR></TABLE>


Damn try to find out more about your theory ??

It took me a day ( 7hours or so ) to do the job and I do not remember how much it cost cuz the exhaust was already on my car but he was fitting sooo bad the shop did a really bad job so I took it out the year after and I cut all the piping with the good angle... basicly it was more complicated than start from nothing lol !

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hawkze_2.3 &raquo;</TD></TR><TR><TD CLASS="quote">

Ya think?? I consider the downpipe a part of the exhaust as it requires the same consideration as the actual exhaust with a turbo.</TD></TR></TABLE>

well seeing that no exhaust (open DP) is optimal for performance, and no DP is not optimal... I would agree that its part of the exhaust system, but may require different considerations since they are not the same.

but yes overall you want little disruption to flow.

however, is there any merit in what I said above about that first 90 deg bend? I mean it's going to be there anyway, but I wasnt sure if it's just how we route the pipe or does it have some other function like what I read about. I didn't want this guy to make a strait pipe out the side of his car then find out he should have that first bend at least...

 

I agree... the DP is there to route the flow of the exhaust of the turbo... imagine the turbo without the DP... it would create a LOT of turbulance imo... !!!

 

props to the exhaust looks outstanding

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by primeredbeast &raquo;</TD></TR><TR><TD CLASS="quote">props to the exhaust looks outstanding</TD></TR></TABLE>

lol it was not the goal of the post but thanks.

 

Post pics when you're done with your dp.

 

Good job on the exhaust! Looks great!

here's a pic of my 3" dp

 

SOHC VTEC NINJA!...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by legendboy &raquo;</TD></TR><TR><TD CLASS="quote">Good job on the exhaust! Looks great!

here's a pic of my 3" dp

</TD></TR></TABLE>

hey thats a nice picture. I will probably try to do a similar design but a straight tubing of 3 or 4 inch just at the exit would be nice.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by legendboy &raquo;</TD></TR><TR><TD CLASS="quote">Good job on the exhaust! Looks great!

here's a pic of my 3" dp

</TD></TR></TABLE>

Nice DP , how many bends did you use? 2x90degees?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turtle-eg &raquo;</TD></TR><TR><TD CLASS="quote">

Nice DP , how many bends did you use? 2x90degees?</TD></TR></TABLE>

yep, one ubend and a peice of straight

 

Mke sure to smooth out the inside of DP if possible. Where the flange meets the Pipe

 

u did an awesome job on that exhaust i love it!!!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">
Is there an importance in the curves of the DP like on a NA header ?
</TD></TR></TABLE>

On NA headers, companies use specific bends and piping that they have found experimentally to be the best for the application. Certain piping methods create vacuums which facilitate the engine's push to get the exhaust out of the manifold, for one. I am sure thats a grave oversimplification of issues, but something like that is pretty much why you see interesting designs on NA headers.

nice exhaust btw

 

Your welding looks so good... Nice job

 

Thanks for your help... it gave me a good idea to how I will do my new DP !