Piper Exhausts turbo downpipe development thread

[Specky]

Standard map, I will get the Everest, I hope it works, because I get fed up with putting my face through the dash.

It's a bugger to watch the boost guage, revs and the road.

TTFN

[whippit]

i got over boost with a piper 2.5" single box,
waste gate was ported to about 20mm, but with a standard map,
installed alan's chip, overboost cured,

the only stupid thing ive done is use the standard nuts from the turbo to the downpipe,
which means the studs will get stripped when i remove them what a fool,

i think a few of us might need some stainless studs and nut's as well

[saska]

Standard map, I will get the Everest, I hope it works, because I get fed up with putting my face through the dash.

Fuel cut on the Std map is 0.92 Bar, on an Everest it is 0.96 Bar so you may or may not get lucky.
Were it me I'd consider taking the wastegate to 21mm.
Yeah, I know, you think I'm probably crazy but consider the following:
Area = πr^2
A 20mm hole has a surface area of 314.14 mm^2
A 21mm hole has a surface area of 346.35 mm^2
the reason that 1 mm makes almost 10% difference is because it is around the outside.
I'm just thinking that this will be a lot easier to do now while the nuts/bolts will come apart.
The Boost Control Valve can't do anything more to stop this effect than it is already doing, so I'd suggest you consider the above to address the problem at it's source -- AKA the wastegate can't loose enough pressure fast enough.

[HJ2]

I had the same thougths. Mine's 21 mm and works like a charm now.
Oh, and with Mountain chip, PECO2,25", and no kat's whatsoever

[superbad]

You might find that the new downpipe improves the wastegate efficiency, by opening up the flow on the outlet and reducing turbulence. Particularly if the two flows are kept separate and merged back together cleanly.

[Specky]

I think 21mm would be cutting it fine on the wastegate, especially when coupled with the amount of end float the flapper valve has got.

I'll just have to save my pennies, if it still overboost I'll have to look at changing the lenght of the rod, mines the early adjustable style.

TTFN

[GeoffSmith]

You might find that the new downpipe improves the wastegate efficiency, by opening up the flow on the outlet and reducing turbulence. Particularly if the two flows are kept separate and merged back together cleanly.

[Specky]

I disagree,

From the overboost perspective that is, it's not so much the size of aperture or the pipe, it's the size of the hole that's created when the wastgate flap opens, it only moves several degrees, now If it did open to 90 degrees...

On the twin pipe front, I have a theory, but I don't know what will happen, but it involves jetpumps and wastegates.

TTFN

[rip]

You might find that the new downpipe improves the wastegate efficiency, by opening up the flow on the outlet and reducing turbulence. Particularly if the two flows are kept separate and merged back together cleanly.

Good point. Turbulence is massively complex & I'm not going to pretend I know the answer.
I'll be interested to try it without touching the wastegate.

[GeoffSmith]

You might find that the new downpipe improves the wastegate efficiency, by opening up the flow on the outlet and reducing turbulence. Particularly if the two flows are kept separate and merged back together cleanly.

Good point. Turbulence is massively complex & I'm not going to pretend I know the answer.
I'll be interested to try it without touching the wastegate.

Seeing the predicted airflow plots of supersonic objects is an eye-opener and not necessarily intuitive. In electrical/electronics terms, it's like comparing audio amplifiers to microwave amplifiers.

[Specky]

You dabble with Laser ring Gyros...this has got to be simple in comparrision....

I thought a laser ring Gyro was a a bit of bling you got from the post office...

TTFN

[GeoffSmith]

Well, it's not rocket science.

[cliff]

Laser Ring Gyro theory is quite easy, basically smoke & mirrors.

Turbulance and airflow especially at supersonic speed is amazingly complex. On a jet engine, basically a turbo at heart, the difference in speed of the the airflow at the blade tip compared to the blade root is vast. Must admit though it's been a while since I did jet engine theory.

Monty wrote:

Wonder if a member that has there name on the "Interest list" has AC fitted will be willing to let Piper test fit

I would be more than happy to, but my car won't be back in the UK before the middle of august.

[drasicjazz]

Does anyone know when this will be ready?

[naughtytortoise]

Does anyone know when this will be ready?

Spoke to Piper recently and hopefully in the next few weeks - prototype is in progress.

[HJ2]

Ooooh boyoboyoboy!

[Specky]

Does anyone know when this will be ready?

Spoke to Piper recently and hopefully in the next few weeks - prototype is in progress.

If you get the piper fitted, M2/A2 Folkstone tunnel with the window down

I do it a couple of times a month

If you've got a 2.5 exhaust and stiffy ( ported wastegate) and a standard chip... Watch out for overboost and fuel cut off...

TTFN

[steve matthews]

Better ask if it is a two pipe assembly or
a single that has already been developed

I would not want LEC to be the banana in front

Just my 2 cents U.S.

Steve -w- two pipe Fed. down pipe and loving it.

[bobbrown]

[HJ2]

No matter what the outcome will be: ANY available solution which improves flow demonstrated is better for me than a discussion on several proto's..
@ the moment i can buy nothing, so i'm happy with any progress

*edit:* Or is the alternative ready and in stock?