Hey guys. I am gathering parts for a TII swap into a 1st gen rx7. I have a wastegate question.

Do you think different brand wasgates (dumped externally/screamers)have higher or lower tone levels? I have to friends that have turboed GSR integra's. One has a turbosmart and the other has a turbonetics & both of them are vented to the atmosphere & are the same size. To me the turbonetics sounds way louder than the turbosmart.

What do you guys think?

P.S. I want a screaming wastegate.

 

the sound depends on several different things, but mostly its just the way the wastegate's built. im sure you can find reviews and such of just about any youd consider.

however, a "screaming wastegate" on a street-driven vehicle will certainly be an attention-getter, but probably the wrong kind. (police or thieves, i dont want either one even knowing i exist)

 

I had a "screaming wastegate" on my 323 GT Turbo and I loved it & I want the same for my rx7. That's why I wanted to know what's the loudest on a rotary motor.

I've never heard one in person (on a rotary).

 

I dont get the appeal at all.
There are a million ways to attract attention and that seems like the last one Id try.Rotaries are excrutiatingly loud,people try all kinds of methods to quiet them down to acceptable street levels.Why make more noise at the wastegate,when you have enough work trying to silence the tailpipe?

 

lynch, get a turbonetics wastegate .. the reason its louder than the turbosmart is because it flows more
oh and the gtx went 12.90 @111 first time out

 

Agreed, personally I want to recirc my Greddy 47mm back into the exhaust. It's a more streetable, and professional setup.

 

When it comes time for a turbo setup in however long of a future that it may be, I will be doing a recirculating setup as well.

 

more streetable , well it is quieter, but wont change driveability not professional....
why not? all the pro's run the w/g vented to atmosphere sir
when you recirculate the w/g back into the exhaust system it increases back pressure wich is bad .. the backpressure can cause boost creep, and power loss..

dan, how cold is it there in ca. ?

 

i'd say make an exhuast specifically for the WG, that would be pretty kool, it could make a very distinct sound

 

I should have changed the way I said that. I just mean that venting a wastegate to the atmosphere is far too loud for a street car (in my opinion). If I was building a race car I would be perfectly fine with it. Personally I feel the proper way to do it for a performance street car is recircing.

As far as the temperature here goes, right now its around -20 degrees celcius. In the summer during the day it's around 20 degrees.

 

Even for a pro, or race only vehicle,that might not be practical.
With so many tracks enforcing noise restrictions now,an open wastegate might only get you one pass down the track before your booted out. And believe me, most tracks are well aware of,and prejudist'd towards the rotaries noise making abilities.
At the very least,stick a little motorcycle muffler on the outlet.....not that its gonna help much on a rotary.

 

I think some of you guys are missing my point. I really don't care about noise. I guess I am an old school type. I love to hear a car screaming down the track, street whatever...
Another thing is the only time you would hear the wastegate is when you are beginning to build boost and from there on it BEGINS to get louder. I'm not going to hit full boost 24/7 & this car is not a daily driver.

I thank everyone for their input & kindness towards noise pollution.

 

having an external wastegate isnt really to loud for the street in my opinion. Cause its not going to be loud unless the wastegate is open, which would be in non street situations. But when it is open its going to be suppppeeeerrrr loud.

 

I understand what your saying, and I can appreciate that.

I just dont know if you are fully aware of how loud a rotary is,especially right there at the exhaust manifold.You made refferences to Integras and the GTX,but nothing rotary specific so far has really come up.
Of course,most people would agree that on a daily driven streetcar,this wouldnt be a good idea.It sounds like your building a car for the track,but even then it might not be the right choice.If your local track enforces noise pollution rules,you might get flagged.Then you wont even be able to race,let alone drive on the road without getting ticketed or hassled.......

 

tial wastegate > *

 

steve84GS TII - thank you for pointing that out and I am fully aware of how loud a rotary is from the exhaust manifold. I know a rotary is way louder than a 4 banger of the header/manifold.

 

I got this sent to me on my behalf:

http://www.alpenmachine.com/rx7/burnin3rd.mpg

These a dual tial 35mm wastegates vented to atmosphere.

 

my car currently is a vented dump..... but when the Gt42 goes on next week i am going to recirculate it back in...

To me i can tell what the engine is doing more when i can hear it, and i love the sound of the compressor compared to the sloppy wastegate sound...

a vented wastegate on a high hp rotary is oboxioius i think.......the more boost and power you run the louder that damn thing gets

I didnt realize how loud it actually is till i had a buddy drive my car as i raced him in his LT1 comaro so that i could listen......... when he flew by me under full boost, i thought my ears were going to bleed.... that is when i new it was time to plumb it in... my opinion

I dont even like to get on it in town because of the noise the wastegate makes when it opens........ although i have a full 3.5" exhaust and it is damn quiet so that makes it more pronouced.... compared to a car that has a loud exhaust

 

"WAAAaaa Rotaries are loud, call the wwwaaaaaa bulance" I think you guys are used to hearing about how loud rotaries are instead of really experianceing it. I drove around with an open header for about 2 months. Didn't bother me at all. Or other people. It was only loud when I was full throttle, and on the street that only happens about once a week. I drove next to cops on the freeway and didn't even get a look over. Only reason I put the exhaust back on was just in case I got a ticket. With a vented wastegate the only time it's going to get loud is when you're really getting into the throttle, and if that's happening on the street alot you're an irresponsible ***** and shouldn't be on the roads anyway.

 

lmao.......right

 

The first year I built my car it had a open WG, for the next year it had the WG plumbed back into the DP. It was fun for a couple weeks but it got old fo rme.