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-   -   When you know your car is loud... (https://www.rx7club.com/1st-generation-specific-1979-1985-18/when-you-know-your-car-loud-101906/)

rx7gslse 08-02-02 10:51 AM

When you know your car is loud...
 
Alright just thought I'd share. I have a friend with an 85 GS w/ a 6port 13b and a holley 650 carb on it..

He works out at a racetrack where they actually have sound measurement equip. He tested his car yesterday...


103dB at 50ft. OUch! That's the standard method they use to test SCCA road race cars. I think the legal street limit is 90dB.

Hey, it shoots like 4 feet of flame out the back though... that's cool, right?

peejay 08-02-02 11:12 AM

not that argument again :) :)

lol my friend has a sound meter. the stereo in my T-bird (just a good pair of well-positioned 6x9's and a decent amp and headunit) would show 123-124 decibels at the driver's right ear. I used to listen to it that loud all the time, and complain that it couldn't get any louder. That's because driving on the highway, the meter would be pegged at 126dB :eek: And that's INSIDE the car...

XLR8 08-02-02 01:33 PM

I believe there is nothing like the sweet loudness of a full open rotary with a header. MMMMMHHHHMMMMM!!!

Jeff20B 08-02-02 01:35 PM

My friend's REPU was so loud that he got pulled over several times and might have been ticketed for it (I've never asked). It was so loud that a guy working at a local gormet burger resteraunt could always tell he was driving his truck. I could hear that truck across a valley at least ½ a mile away as the crow flies, even over the local road noises and a flowing creek at the bottom of the valley. Man, that was the loudest rotary around here for a while.

rx7gslse 08-02-02 02:55 PM

well put it this way.. that is the same test Setup they use to test SCCA road course cars. 103dB is the limit for those cars according to him.

and trust me, its loud!

Defprun 08-02-02 02:58 PM

I can't wait until my cars that loud.

Hyper4mance2k 08-02-02 03:26 PM

i had a civic with a header weber and 2 1/4 pipinf from the header to a 40 series flowmaster... talk aboot loud it was prolly the only car that sounded like it.. at idel it sounded like a 454 just gurgeling and when i steped on it ohhh gawd!! my friends said they could hear me comming for like 5 minutes before i got to their house

Sterling 08-02-02 06:57 PM

My cars SOOOO LOUD...Yer momma gets all wet cause she thinks I'm on my way ta her house again - She can hear me all the way over here in NY!!!

ioTus 08-02-02 07:21 PM

I have a RacingBeat Street port header and center section, with a free flowing 2.5" overaxle into a 2.5" in, straight through dual 3" tips (dual 2.5" out).

It has got to be the sweetest sounding ride around. Now for the rebuild, port job, intake, and carb!! Then it will be fast, too.

khaine_d 08-02-02 09:40 PM

Flowmaster? ha I laugh at it. For performance, hooker is better, thats like tieing a knot at the end of your headers. It really chokes out the engine. Some stock mufflers actualy will out perform FM.. Your call though that's just my experiance. I switched my old mustang..(the darker days of my life)from flowmaster to raven. The improvement was enough that I put plastic seat covers on my car so I didn't have to keep geting the seats cleaned..lol Raven has a very definate sound, metalic, slightly loud. and it's a free flow muff anyway check them out.

peejay 08-02-02 10:24 PM

i love norwalk... no noise restrictions there. they are after all the IHRA headquarters :)

open up them headers and let them rotaries scream!

diabolical1 08-02-02 11:41 PM

i ran open headers on the highway once and a guy on a motorcycle (with helmet) heard me coming ... from behind him

true story ... :D

RotorMotorDriver 08-02-02 11:45 PM

Yeah, I had my car open headers once, but my Dad wouldnt let me leave the driveway with it :). It was shaking the windows in the house about 25 yards away when the engine was at an idle :D. Now, I have RB header and pre-silencer, with the stock blown muffler, and its still fairly loud :). Im going to invest in a power pulse muffler soon, hopefully it will sound nice :)

~T.J.

Rotary-MG 08-03-02 02:51 AM

This is what I bought for my rotary.
Stealthy one moment, open the next.
Best of both worlds!

http://www.geocities.com/sykumash/Engine/cutout.txt

see the JC Whitney on-line catalog

peejay 08-03-02 02:55 AM

Let me know how long that works until the flapper rusts to the point where it doesn't seal well.

I was considering one of those, but decided on the "Race Ready" unit - you have to get out, crawl under, and remove three hot wingnuts (they do provide a cheesy-yet-useful wingnut wrench) and a VERY hot plate. But I had the peace of mind in knowing that I'd never have leaks :)

Be careful to know that your tuning will drastically change wih the cutout open vs. closed. When you open it up, the car will run a LOT leaner.

Rotary-MG 08-03-02 03:01 AM

The flapper ain't that thick.
But I'm ready to weld on a 1/4" thick stainless piece once that's gone. Maybe I'll do that before installing it.
Great idea!!! thanks!

I'm running the EGI, so I wonder if the injection will take care of the lean issue?

It's mostly for fun. Those times I want to scare my local rice racers! I'm asian too, so I can call them that.

peejay 08-03-02 03:07 AM

Ooh, good call. Hopefully the EGI will handle the lean issue, since it would compensate for the airflow change.

That's one thing I really wanted with that setup, EFI.... It was too much of a hassle to keep going from "track tune" to "street tune" and back again, so I eventually gave up and left it in "track tune" and lived with the crappy gas mileage until the race season was over, then went back to "street tune".

MIKE-P-28 08-03-02 07:19 AM


Originally posted by peejay
not that argument again :) :)

lol my friend has a sound meter. the stereo in my T-bird (just a good pair of well-positioned 6x9's and a decent amp and headunit) would show 123-124 decibels at the driver's right ear. I used to listen to it that loud all the time, and complain that it couldn't get any louder. That's because driving on the highway, the meter would be pegged at 126dB :eek: And that's INSIDE the car...

When I had my 3 JL Audio 12W'6 in my car. If I drove through the mall and I didnt set of 3+ alarms. I was unhappy :)

peejay 08-03-02 10:15 AM


Originally posted by MIKE-P-28


When I had my 3 JL Audio 12W'6 in my car. If I drove through the mall and I didnt set of 3+ alarms. I was unhappy :)

That was the beauty of my install... the sound energy was directed right at the front passengers' ears. That, and the naturally well-insulated nature of an early seventies land yacht, you could NOT hear the system from outside the car unless the windows were open. And even then, you didn't hear much... until you stuck your head in through the window... :) It was like the Cone of Silence from "Get Smart" but in this case it WORKED.. :D :D

Now... with a car THAT insulated... imagine how loud the exhaust was to make it 126++ dB on the INSIDE of the car. Setting off car alarms was my hobby :D


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