Jump to content

Mufflers


Chill
 Share

Recommended Posts

No idea, but what meets the 96db rule depends on the car.  We run straight through vibrant resonator and muffler and are well below.

 

Intake location and design also contributes to a cars noise, so keep that in mind as well.

Link to comment
Share on other sites

13 hours ago, Chill said:

Has anybody used Spin Tech mufflers? What mufflers will meet the 96 dB rule?

I used one on my RX7 for many years. The technology is similar to a Flowmaster. No sound deadening to deteriorate. Lots of knock off versions too. I’m using a knock off version on my E30. 
To reduce sound level definitely exit out the rear. Direct up is best IMO. But us an elbow that can be rotated for best results. 

Edited by TimS
Link to comment
Share on other sites

1 hour ago, TimS said:

I used one on my RX7 for many years. The technology is similar to a Flowmaster. No sound deadening to deteriorate. Lots of knock off versions too. I’m using a knock off version on my E30. 
To reduce sound level definitely exit out the rear. Direct up is best IMO. But us an elbow that can be rotated for best results. 

Who makes knock offs?

Link to comment
Share on other sites

On 4/30/2022 at 2:39 PM, TimS said:

I used one on my RX7 for many years. The technology is similar to a Flowmaster. No sound deadening to deteriorate. Lots of knock off versions too. I’m using a knock off version on my E30. 
To reduce sound level definitely exit out the rear. Direct up is best IMO. But us an elbow that can be rotated for best results. 

who makes a knockoff of a spin tech?   

everyone copies flowmaster

Link to comment
Share on other sites

Bill, Which Spin tech do you use? This is "Eliminator"

Oval Eliminator, 2991-35, (Pair)Oval Eliminator, 29910-35

    

2000 Oval Eliminator 

SpinTech 2000 Oval Eliminator Our Pure-bred Race Muffler used extensively in Southwest Tour, Craftsman Truck, and Winston West Case Size: 3" x 10 1/4" x 15" A proven winner able to meet decibel levels where required Available in Dual, Side and...

Link to comment
Share on other sites

22 hours ago, Bill Strong said:

3000F Sportsman- Low Profile Muffler

 

1.9 liter 6000rpm 100hp engine.

 

We use the same one.

 

2.3L 6500rpm 180hp engine. Side exhaust. Passed @ Road America with 76db according bills meter.  

  • Like 2
Link to comment
Share on other sites

  • 2 weeks later...

Our Miata has 3 cheap mufflers (pass thru or whatever) in our exhaust and it's one of the most quiet car on track.

Penalty is maybe 10lbs.

 

We started with a single tiny muffler, car was insanely loud and not even close to pass any regulation. Instant ear damage.

 

But adding more resonance/mufflers in the pipe really helped. 

 

(Edit: while the mufflers are cheap, fabbing cost a few hundreds)

Edited by turbogrill
Link to comment
Share on other sites

  • Administrators
32 minutes ago, Chill said:

Will Spin Tech Mufflers last longer?

 

There is no glass to blow out. 
The stainless version will take heat better. I suspect the stainless will last a few seasons. The mild steel would most likely be a season of two. (10 or so races a year.)

Link to comment
Share on other sites

2 hours ago, turbogrill said:

Our Miata has 3 cheap mufflers (pass thru or whatever) in our exhaust and it's one of the most quiet car on track.

Penalty is maybe 10lbs.

 

We started with a single tiny muffler, car was insanely loud and not even close to pass any regulation. Instant ear damage.

 

But adding more resonance/mufflers in the pipe really helped. 

 

(Edit: while the mufflers are cheap, fabbing cost a few hundreds)

Yup.  Same experience.

 

Small pass-through at about the tail of the transmission, then back under the spare tire area another Thrush/Cherrybomb/Purplehorny and the car is much quieter than most.  At the dyno, we took the last bit off and let it dump at the diff.  1HP across the rev range.  And with a ringing in our ears, we put the second muffler back on.

  • Like 3
Link to comment
Share on other sites

  • Technical Advisory Committee
11 hours ago, Chill said:

Will Spin Tech Mufflers last longer?

 

10 hours ago, Bill Strong said:

 

There is no glass to blow out. 
The stainless version will take heat better. I suspect the stainless will last a few seasons. The mild steel would most likely be a season of two. (10 or so races a year.)

Borla mufflers are high quality, lifetime warranty, and sound great. 
made of stainless steel with no glass filler. 

Edited by mcoppola
  • Like 1
Link to comment
Share on other sites

When I put the fresh GS-R engine in the Civic, I took the opportunity to increase the size of the exhaust, install a different muffler at the rear of the car, and revise the air intake system to pull cold air from the cowl area:

image.jpeg.b518a1ab4a54ab64aed5a117f5688b6e.jpeg

 

Pretty pleased with the performance of the car but was a bit puzzled by the large increase in noise, enough that I had to wear ear plugs. I put a second muffler in the middle of the system but no change in the sound level, couldn't hear the radio and still had to wear ear plugs. 

 

When I was cleaning up the wiring last fall, I noticed this:

image.jpeg.2ee33a406d1e847d6bfa05c471767070.jpeg

 

I missed closing off a hole in the firewall. That's the air filter peeking through the hole, and that explains why there was so much more noise inside the car after the mods! Induction sound level while in VTEC is pretty loud! I now have that sealed so should have a drop in decibels plus hopefully a bit more performance by using the higher pressure air in the cowl area. 

 

I haven't had the car out yet this year but we have a test session coming up in two weeks, pretty sure that'll quiet things down.

 

TL; DR - it's not just the exhaust that makes noise.

Edited by mender
  • Like 2
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...