i know i would gain power by dumping into the atmosphere b/c my dumptube is to close to the turbo...



but does it matter if i'm running an open downpipe? if it does how much power am i losing b/c its a closed loop set up. i wanted to redo it but i can't figure out where to make the dumptube go. is it worth redoing?

 

i'm interested in knowing this also, i know there has been alot of talk about it, i'm redoing my setup wich was closed, now it will be open just cause it might make more power and also cause i'm getttin a new dp and it's just easier to make it open instead of closed........

 

well first off i would get rid of that wastegate. then i would dump it into open atmosphere or change it to dump back in 18" away from turbo. i think thats the right length. somone else back me up

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TeStUdO &raquo;</TD></TR><TR><TD CLASS="quote">well first off i would get rid of that wastegate. then i would dump it into open atmosphere or change it to dump back in 18" away from turbo. i think thats the right length. somone else back me up</TD></TR></TABLE>

get a tial... deltagates = boost creep

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TeStUdO &raquo;</TD></TR><TR><TD CLASS="quote">well first off i would get rid of that wastegate. then i would dump it into open atmosphere or change it to dump back in 18" away from turbo. i think thats the right length. somone else back me up</TD></TR></TABLE>

 

yeah... i've heard this wastegate creeps... but it has not happened to me yet. it came w/ the kit so i used it... but imma buy a tial soon.. i was already planning on it b4 i even put the turbo on.

 

i had a deltagate...freaken center shaft shattered on me leaving the wg wide open during first track run!!! damn cheap POS!! just got my new Tial 38mm WG today!! compared center shafts...damn the Tial is 4 times thicker!! now that's what i call quality!!

 

I remember a while back when Super Street (I think) did a test on a Prelude FMAX kit. The HP differential between closed and open loop was 20-30hp. I do not remember the exact figure but I vaguely remember the upper figure was 244hp. If anyone has the article still please verify.

 

Ive seen 2 cars they tried both and with the open loop the car gians alot more power on a 521hp civic made 540ish with it pluimbed out.

 

yeah the way you have it set up now doesnt look to good...just think of all the exhaust gas coming out of the turbo flowing through the exhaust...then the wastegate opens and slams gases sideways against them causing a bunch of turbulance.

if you are going to plum it back in, do it furth down the exhaust and try to make it so the flow of the dump tube goes with the flow of the exhaust.

 

Even if you have it plumbed back into the exhaust farther down you would still see a decrease in HP. So basically there is no way to run a closed loop setup and see similar HP numbers to a open look?

 

test it out for us when you do it. If you can get on a dyno now and see how much HP you are then do it again after you do open loop or run it further down the exhaust.

 

I don't know if it's possible to have absolutely NO power loss. But you can keep it to a minimum by doing what was said above. Introduce the dumptube further down into the downpipe (closer to the cat) and reduce the angle at which it merges with the downpipe.

That's why the FMax test on the Prelude showed such a difference. The dumptube was at a horrible angle and too close to the turbo.

 

it is a modified drag manifold...
i was told by many that my hp is suffering b/c of this. so i'm currently redoing it. as far as comparing the 2, i cant b/c when i'm putting my car on the dyno this friday i'm getting my hondata tuned and i will be running open downpipe. so comparing would be useless.

 

Great, let me be the guinea pig.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by gritsak &raquo;</TD></TR><TR><TD CLASS="quote">yeah the way you have it set up now doesnt look to good...just think of all the exhaust gas coming out of the turbo flowing through the exhaust...then the wastegate opens and slams gases sideways against them causing a bunch of turbulance.

if you are going to plum it back in, do it furth down the exhaust and try to make it so the flow of the dump tube goes with the flow of the exhaust.</TD></TR></TABLE>

I couldnt agree more. The way you have it is probably causing a power loss, and that is probably the only thing that will create a power loss in the never ending open/closed dumptube debate. The way i was taught, if its done correctly, it does not matter (performance wise) if its open or closed loop. But if i WAS to close-loop it, Id keep it about 14-18 inches away, and id make it a 45 degree angle bend into the downpipe. The way you have it now, as stated earleir, is going to create turbulence.

 

i run a drag manifold with open downpipe w the deltagate no boost creep at all. but i ported my wastegate hole, i guess that helps a lot