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[highroller54]

I am shoping for some more eg parts (fuck you xenocron your not getting any of my money) but tell me about wastegates, open vs closed loop, I'm being told you loose power with it routed back into the exhaust but why unless your exhaust was too small.

[patsmx5]

It all depends. If you dump the EWG under the engine bay and the air filter picks up some of it, then you loose power pulling because the % of O2 going in the motor goes down. Automatic EGR.

On the other hand, recirculating the gasses is bad as that ups the mass flow rate going through the exhaust, ups the backpressure, etc. Also reintroducing the stream of gases from the EWG smoothly can be challenging as well.

That said, I like quiet shit so mine dumps in at a 90* angle 5" from the turbo. Not ideal by any means, but works. I'll redo it one day I guess.

[highroller54]

Thats basically what I was thinking, I cant see a car with 3 or 3.5 or 4inch exhaust being much of a deal though. I planed on going back to the firewall area with it and merging there at a gentle angle.

[BoostForLife]

Do you not like the sound of an open waste-gate? Put a mini-muffler on it.

[patsmx5]

Thats basically what I was thinking, I cant see a car with 3 or 3.5 or 4inch exhaust being much of a deal though. I planed on going back to the firewall area with it and merging there at a gentle angle.

Yeap. I want to put a piece of 4" pie cut love coming off the turbine and combine the WG's flow down below the car. But that's easier said than done on a miata.

[highroller54]

Do you not like the sound of an open waste-gate? Put a mini-muffler on it.

I dont want the smell or the sound

But that's easier said than done on a miata.

I could see that, lol

[patsmx5]

Seriously, it was pure hell making a 3" pipe fit and be removable without having to drop the rest of the exhaust or pull the turbo. V-band will be welded to the turbine next time that shit comes off. I don't care how much they cost; they're a bargain at any price.

[BoostForLife]

Seriously, it was pure hell making a 3" pipe fit and be removable without having to drop the rest of the exhaust or pull the turbo. V-band will be welded to the turbine next time that shit comes off. I don't care how much they cost; they're a bargain at any price.

V-bands are awesome, much faster and easier to take things off.

[stealthiskey]

V-bands are awesome, much faster and easier to steal things off.

fixed

[Urban Indian]

Do you not like the sound of an open waste-gate? Put a mini-muffler on it.

Or a megaphone

[89hatchsir]

I've never seen anyone run a megaphone on their dump pipe. Looks good but hows it sound?

[highroller54]

Do you not like the sound of an open waste-gate? Put a mini-muffler on it.

Or a megaphone

you are a animal 

[Urban Indian]

I've never seen anyone run a megaphone on their dump pipe. Looks good but hows it sound?

Havent run them yet.


And it was Dave @ Passenger's idea

he is the crazy one. I like the idea though. He said it keeps them quieter apparently?

[patsmx5]

I've never seen anyone run a megaphone on their dump pipe. Looks good but hows it sound?

He said it keeps them quieter apparently?

[Passenger]

I've never seen anyone run a megaphone on their dump pipe. Looks good but hows it sound?

He said it keeps them quieter apparently?

Strange but true, I've done back to back testing with my DB meter.

[patsmx5]

I've never seen anyone run a megaphone on their dump pipe. Looks good but hows it sound?

He said it keeps them quieter apparently?

Strange but true, I've done back to back testing with my DB meter.

Try testing it vs. a straight piece of pipe? I can see it changing the frequency, but not the actual dB.

[Passenger]

Yes vs 1.5" straight tube, difference was only around 8-12DB IIRC, I'll have to look through my notes.

[Aero]

Yes vs 1.5" straight tube, difference was only around 8-12DB IIRC, I'll have to look through my notes.

That is a fairly noticable change to the ear though if thats true.
 

[HiProfile]

Yes vs 1.5" straight tube, difference was only around 8-12DB IIRC, I'll have to look through my notes.

That is a fairly noticable change to the ear though if thats true.
 

Megaphones amp your voice because they direct it all one way, the dump is already dumping noise in one direction so the megaphone probably widens the path. And 10dB is half as loud.

I prefer to recirculate it on a street car. My current setup has a 3" turbo-back to the gas tank, which goes one way to an e-cutout and one way to the stock muffler. If you thought a bone-stock Civic was quiet... Personally I think people (fabricators) just get lazy and make those claims. The people that do recirc put it very close the turbine outlet and don't give it much of an angle. They'll spend a lot on a cool manifold, but completely forget a dump tube should merge as smooth as their manifold. My HMT setup hits it with a ~60* roughly 20" after the turbine outlet.

[speedjunky01]

pic of said rerouting?

here is how i did mine but never made it to a running car to test it out, will be on the 4dr in a week or two.



i think ill redo the DP make it AC and PS friendly but it will be hard to plug it back in far down the DP since the turbo will be the other way

[t_cel_t]

I've never seen anyone run a megaphone on their dump pipe. Looks good but hows it sound?

Havent run them yet.


And it was Dave @ Passenger's idea

he is the crazy one. I like the idea though. He said it keeps them quieter apparently?

guy i know whose been making exhausts for like 30 years told me that if you go from a small pipe and flare it out larger it removes the raspyness and quiets it down, didnt believe him untill he put a strait pipe up to my exhaust and revved it (raspy as hell) and then he expanded it on his bender and stuck it back up and there was no raspyness whatsoever.