Bolt on downpipes and exhausts bits for stagea ?

[AlexCim]

The idea of a split dump pipe is that there is turbulent gasses coming out of the a) wastegate and B) turbine.

The reason that a split DUMP is poor is because, sure, they are split, but they are only seperate for what, 10cm. Also when the wastegate gas enters back, it enters at a big angle therefore creating more turbulence. This is why a split DUMP is not worth it, if you still using a front pipe. If you are going to do it seperate, get a sinlge DUMP and front pipe.

The less turbulence the better the flow, as its more smooth.

This is why a dump/front in one is perfect, specially when split. The gasses are seperate for a good 1/2m which allows easy exit from the turbine and wastegate. Also, the entry angle back to the pipe is very good, meaning both gasses just "mesh" together and dont create more turbulence.

From this, going off what my friend said in his 200sx, the split DUMP is more restricitive if using seperate front/dump, so he bought a single. The split gives more power down low, with response but is restrictive up top

BOS importing trials show the split pipe (even in single mode dump/front) makes like 15kw move atw overall.

So from that, conclude that split dump/front in one is best overall. More response, better flow, more top end power.

And that is why i bought the SS split dump/front in one...

[Sydneykid]

Hi Talej, emanuelt, AlexCim do you guys have a digital camera? Can you pleasae post up some photos.

1. It makes no sense that the lambda sensor would hit on the exhaust manifold, the lambda sensor is on the top of the dump and exhaust manifold is on the side. The Stagea exhaust manifold, turbo, heat shielding and standard dump are all the same as the R33GTS. So unless BOS has made a one off manufacturing error, there should be absolutely no problem in that area.

2. The floor pan on the Stagea is supposed to be the same pressing as the R33 from the B pillar forwards. So the R33 dump/engine pipe combo should fit the Stagea. This is where some pictures would come in handy. It would be nice to know if we are dealing with a dump pipe manufacturing error or whether there is some difference that we need to be aware off.

Alexcim's comments (or rather his 200SX owning mate's) back up what we have found. The separation of the spinning exhaust from the turbine and the tumbling exhaust from the wastegate needs to be at least 400 mm. This allows time for the spinning to be controlled (eliminated) by the enlarged exhaust pipe and for the tumbling of the wastegate exhaust to be turned into flow. The blending of the two then can occur without creating the turbulance that robs power.

The phenomon of less low end power from a split dump (and more high end power) is totally illogical as the wastegate shouldn't be open, so whether it is a split dump or a combo should make no difference. The only issue could be if the turbine outlet pipe is too small, but if it is too small at lower rpm then it sure as hell is going to be too small at high rpm.

The reverse, more low end power from a split dump (and less high end power) is somewhat more logical. But again only if the turbine exhaust pipe is too small or the wastegate outlet rejoins it too close to the turbine as per above.

Back to the problem at hand, anyone got any pictures of the problems?

cheers

[AlexCim]

Its OK,

I have spoken to Micheal at BOS and we have concluded that it is two things

1, because he uses a new manufacturer for the stainless pipes, the flange on the turbo side is not sitting at the correct angle, which made me have to lean the pipe UP (was tilted back) to fit, but because it was hitting the floor, it didnt fit. So he will check the angles on the stainless ones, teh mild ones are ment to be fine.

2, the CES pipes have the o2 on the other side of the pipe to std. What the split pipe does it cause the o2 to sit on an angle so that it touches the heat sheild on the manifold. I have also discussed this and he is putting the o2 on the other wise, so it will sit "upside down". He said that with the split pipe, in most cases its been the o2 coming CLOSE, really close, but not touching. It is to the do with the angle that its welded in, so maybe using a new manufacturer again, some kinks being worked out of the system.

Micheal will release a new revision of the split pipe probably soon i guess. I want to install mine, as my Fujisubo exhaust arrives in... 10 days!

BTW, the catco SS inside cat fits fine with the std plumbing. I just didnt put it in yet because i would rather do it all in 1 go...

We will be fine fellow stagea owners! We will be fine!

[Sydneykid]

Its OK,

I have spoken to Micheal at BOS and we have concluded that it is two things

1, because he uses a new manufacturer for the stainless pipes, the flange on the turbo side is not sitting at the correct angle, which made me have to lean the pipe UP (was tilted back) to fit, but because it was hitting the floor, it didnt fit. So he will check the angles on the stainless ones, teh mild ones are ment to be fine.

2, the CES pipes have the o2 on the other side of the pipe to std. What the split pipe does it cause the o2 to sit on an angle so that it touches the heat sheild on the manifold. I have also discussed this and he is putting the o2 on the other wise, so it will sit "upside down". He said that with the split pipe, in most cases its been the o2 coming CLOSE, really close, but not touching. It is to the do with the angle that its welded in, so maybe using a new manufacturer again, some kinks being worked out of the system.

Micheal will release a new revision of the split pipe probably soon i guess. I want to install mine, as my Fujisubo exhaust arrives in... 10 days!

BTW, the catco SS inside cat fits fine with the std plumbing. I just didnt put it in yet because i would rather do it all in 1 go...

We will be fine fellow stagea owners! We will be fine!

<{POST_SNAPBACK}>

Sounds good, except you should NEVER put lambda sensors in the exhaust upside down. They get condensation in them and this causes them to fail. Lambda sensors should ALWAYS face downwards.

cheers

Edited September 5, 2005 by Sydneykid

[AlexCim]

Crap..

This is the CES pipe

This is where we are going to put it

Do you think that will cause any problems? If so, please contact micheal at BOS Importing [[email protected]]

[PranK]

Hmm, I just got a 3" dump/front pipe and 3" hi-flow cat fitted and neither the R34 GTT or R33 Gtst 1 piece dump/front pipes fit, we needed to cut and weld the GTT one (closest fit) to make it sit ok.

[Sydneykid]

Crap..

mmmmmmmm

This is from the Bosch lambda sensor installation manual;

  Do NOT install it below the 3 o'clock or 9 o'clock position. Condensation can form in the exhaust pipe and permanently damage the sensor.

This is from the Microcraft ECU closed loop tuning manual

6) Lambda sensor use and care

Install the sensor in a minimum of 10 deg upward position to avoid the trapping of condensation in it.

I have a few more, but I think you get the drift.

cheers

Edited September 6, 2005 by Sydneykid

[Loop]

I think AlexCim meant "Crap.." as in "That sucks ", not "I think you know not what you are talking about"

[Talej]

no digital camera yet sorry...

[AlexCim]

haha, yes, i definatly ment crap as in "oh fark"

[AMS]

:lol: :lol: :lol: hehehe

[Sydneykid]

haha, yes, i definatly ment crap as in "oh fark"

<{POST_SNAPBACK}>

Oh crap (your meaning), I was hoping for a heated debate :lol:

cheers

[PranK]

Oh crap (your meaning), I was hoping for a heated debate :lol:

cheers 

I'll debate with you SK, whats the topic?

[Sydneykid]

I'll debate with you SK, whats the topic?

<{POST_SNAPBACK}>

You should know I am very selective, I only enter debates that I can't loose. :lol:

Well shouldn't loose, anyway

cheers

PS; not very many funny faces to choose from on the new forum, got an update planned?

[PranK]

yeah, all the smilies from the old boards are coming over

[Terminal]

You should know I am very selective, I only enter debates that I can't loose. :lol:

Well shouldn't loose, anyway

You mean debates you can't 'lose'