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Rb 2860-5 Highest Hp?

Jc052685

By Jc052685,
in Engines & Forced Induction

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fatz
fatz

Ps ausi blokes love a good stir and seppos are known for getting but hurt when their 700hp car gets hosed by a ausi 500 hp car so your an easy target Sadly you joined in the fun and didn't get all Am

hattori hanzo
hattori hanzo

Dash fives get the guys

iruvyouskyrine
iruvyouskyrine

They didn't import them they just sailed them over and keep them docked in the harbour when not using them on land.

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mr skidz Veteran

mr skidz

Posted
Posted

you "could" do this.. 3" dump -> Cat (because we are sensible) -> 3.5" Cat Back... plumb gate back into 3.5" cat back.. bypassing the cat :)

legal enough.. at EPA they won't be cracking gates.

If your bypassing the cat you might as well not have one
Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted

If your bypassing the cat you might as well not have one

But on doodling you're doing the right thing.. external is for party time!

Also when they test your car for emissions it's like at 100kPa or so which means the gate is shut so all your exhaust is flowing through the cat.

On another note, regardless of bypassing cat on noise or not it's still going to make less pollution than a VW, or Audi or Skoda, etc. Lol

mr skidz Veteran

mr skidz

Posted
Posted (edited)

But on doodling you're doing the right thing.. external is for party time!

Also when they test your car for emissions it's like at 100kPa or so which means the gate is shut so all your exhaust is flowing through the cat.

On another note, regardless of bypassing cat on noise or not it's still going to make less pollution than a VW, or Audi or Skoda, etc. Lol

And std ecu Ducati's [emoji23] they also run so lean they occasionally stall and run so hot that they burn your legs.

Remap req

Edited by mr skidz
XGTRX Veteran

XGTRX

Posted
Posted

You guys realize the gate is shut when its building boost....

Exactly.^^^^^

Can't see how plumbing the screamer back in can contribute to lag. When building boost the only thing that causes back pressure issues is the size of the dump.

mr skidz Veteran

mr skidz

Posted
Posted

Exactly.^^^^^

Can't see how plumbing the screamer back in can contribute to lag. When building boost the only thing that causes back pressure issues is the size of the dump.

Well the example I gave was pretty basic if a 3 inch exhaust was used for these 450wkw power levels obviously it would be too small but if an external gate was used it wouldn't be so much of a problem in this case it would affect the midrange dramatically from too much back pressure, think about it.

My point was if you don't need to plumb the gate back in then I don't think you should but if your like Paul and you hate the sound of a gate then do it properly like he is and go big and all should be fine.

Anytime you merge two pipes into a collector there's always a compromise in out right flow it may not be much but it still exist.

XGTRX Veteran

XGTRX

Posted
Posted

I think you are getting confused. The gate is shut to a predetermined pressure commonly controlled by an ebc, therefore there is no positive pressure on the gate diaphragm. So if the spring pressure is 15psi then the you set the ebc to 14 psi. The gate remains shut to that point, so no flow through the screamer, so it's impossible to contribute to lag.

If when its open when the screamer and dump is flowing and the exhaust hasn't got enough flow then you will encounter all the symptoms on a restrictive system where your power plateaus, boost targets cant be achieved....etc etc. But this will only happen if the exhaust system is restrictive AFTER the union of the dump and screamer.

Has nothing to do with lag which is when and how quickly boost transitions.

If the dump is too small, then yes it will cause lag, as we all know, but an open or plumbed scream makes no difference until the gate opens above the set level and will only affect higher mid range and top end IF the rest of the exhaust system is not able to cope with the gas flow.

XGTRX Veteran

XGTRX

Posted
Posted

Going single also can be risky if your not willing to external gate to atmosphere, i know people who plumbed back gate into 3" exhaust and wonder why its a laggy pig.

This is your post.

What you wrote is wrong.

Not that I care. Just saying

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