Midship Runabout » Exhaust http://www.midshiprunabout.org The Toyota MR2 Internet Archive Fri, 02 Apr 2010 06:50:19 +0000 http://wordpress.org/?v=2.8.4 en hourly 1 Exhaust Controller Valve http://www.midshiprunabout.org/mk2/951/ http://www.midshiprunabout.org/mk2/951/#comments Wed, 14 Dec 2005 17:13:34 +0000 Darkday http://www.midshiprunabout.org/?p=951 In order to quiet down my new exhaust, I picked this up off eBay, almost ordered the 2.25″ one, so make sure you get the right size. The valve opens or closes at the touch of a button. You can have it full open, or full closed, or anywhere in between.
I did some tests with a Radioshack Decibel Meter (model 33-2055, the digital one). I compared the KO Racing T1 Exhaust with the Exhaust Valve Controller with and without the silencer, to a Greddy Power Extreme (known for being a pretty quiet exhaust) that has been modified with a block off plate where the drivers side muffler normally sits.
Here is the data from the test.
What I learned was that the valve controller dropped the noise about 2-3db on average throughout the rev range. One thing that interested me was that peak noise was at different RPM for different exhausts (for the T1 was about 5,000rpm, and 4,500 for the Greddy), and that levels drop of significantly by 7,000rpm. It didn’t matter which way the exhaust was setup, the decibel levels always dropped to 84 by 7,000rpm. What is happening is the exhaust note gets lower after 5,500rpm, and the engine noise crosses over while the exhaust noise is dropping. So by 7,000rpm you are only hearing the engine noise, no matter which exhaust was on the car. I never noticed that before, but now when I pay attention, that’s exactly what happens.

 

 

This fits in one of the switch holes next to the fog lights perfectly.

Mounted.

 

Fully closed in this pic, plenty of exhaust can still get by the sides of the valve, but the noise level is way lower. Power is down too, but just push the button, and power is back.

 

Closed here, but you can’t tell because it’s mostly all carbon black now.

The following was grabbed somewhere off the web. -Pat

 

Decibel (Loudness) Comparison Chart

Here are some interesting numbers, collected from a variety of sources, that help one to understand the volume levels of various sources and how they can affect our hearing.

Environmental Noise
Weakest sound heard 0dB
Normal conversation (3-5′) 60-70dB
Telephone dial tone 80dB
City Traffic (inside car) 85dB
Train whistle at 500′ 90dB
Subway train at 200′ 95dB
Level at which sustained exposure may result in hearing loss 90 – 95dB
Power mower 107dB
Power saw 110dB
Pain begins 125dB
Pneumatic riveter at 4′ 125dB
Jet engine at 100′ 140dB
Death of hearing tissue 180dB
Loudest sound possible 194dB
OSHA Daily Permissible Noise Level Exposure
Hours per day Sound level
8 90dB
6 92dB
4 95dB
3 97dB
2 100dB
1.5 102dB
1 105dB
.5 110dB
.25 or less 115dB
Perceptions of Increases in Decibel Level
Imperceptible Change 1dB
 Barely Perceptible Change 3dB
Clearly Noticeable Change 5dB
About Twice as Loud 10dB
About Four Times as Loud 20dB
Sound Levels of Music
Normal piano practice 60 -70dB
Fortissimo Singer, 3′ 70dB
Chamber music, small auditorium 75 – 85dB
Piano Fortissimo 84 – 103dB
Violin 82 – 92dB
Cello 85 -111dB
Oboe 95-112dB
Flute  92 -103dB
Piccolo 90 -106dB
Clarinet 85 – 114dB
French horn 90 – 106dB
Trombone 85 – 114dB
Tympani & bass drum 106dB
Walkman on 5/10 94dB
Symphonic music peak 120 – 137dB
Amplifier rock, 4-6′ 120dB
Rock music peak 150dB

NOTES:

  • One-third of the total power of a 75-piece orchestra comes from the bass drum.
  • High frequency sounds of 2-4,000 Hz are the most damaging. The uppermost octave of the piccolo is 2,048-4,096 Hz.
  • Aging causes gradual hearing loss, mostly in the high frequencies.
  • Speech reception is not seriously impaired until there is about 30 dB loss; by that time severe damage may have occurred.
  • Hypertension and various psychological difficulties can be related to noise exposure.
  • The incidence of hearing loss in classical musicians has been estimated at 4-43%, in rock musicians 13-30%.

Statistics for the Decibel (Loudness) Comparison Chart were taken from a study by Marshall Chasin , M.Sc., Aud(C), FAAA, Centre for Human Performance & Health, Ontario, Canada. There were some conflicting readings and, in many cases, authors did not specify at what distance the readings were taken or what the musician was actually playing. In general, when there were several readings, the higher one was chosen.
]]> http://www.midshiprunabout.org/mk2/951/feed/ 0 4 EGT to 1 Switched Gauge Install http://www.midshiprunabout.org/mk2/4-egt-to-1-switched-gauge-install/ http://www.midshiprunabout.org/mk2/4-egt-to-1-switched-gauge-install/#comments Sun, 08 Aug 2004 16:30:31 +0000 Darkday http://www.midshiprunabout.org/?p=925 Forward: We do NOT reccommend drilling into your ex. manifold with it on your car. Shane and Pat pulled the motor shortly after, and when Shane pulled the head, he found evidence that this procedure cannot be performed safely in this manner. The head had to be machined proffessionally to remove the damage where some of the shavings had been smashed repeatedly before exiting the engine. Apparently, some of the shavings were left in the manifold, and upon starting the engine, they were sucked in on a down stroke, and caused the damage. It has been said on the message board that you can do this procedure with the car running to fix the problem, but we think it would be to cramped, and way too HOT! See this link for more info Gecko 2 Head machine work

4 EGT to 1 Switched Gauge Install

Recently, Shane Craddock installed 4 Westach EGT Probes in his Exaust Manifold, and hooked them up to a single switched Westach Gauge. The install was done with the manifold on the car, which normally is not recommended because metal shavings fall into the manifold, and can get stuck in the turbo, but the procedure can be done with the use of some simple tricks. EGT Preliminary test results at the bottom of the page.

 

Here’s a pic of the special drill bit used to cut through the manifold.

 

Show here are some pictures of ways to get the metal shavings out of the manifold. First was the use of a magnet tipped utility tool, and second a more difficult item to get, a vaccuum attatchment (only use when Girlfriend/Wife is not looking.

 

 

 

Next you need to “tap” the holes you drill in order to give the EGT “bungs” something to screw into securely. We’ve learned to always use the special “tapping” oil to keep the tap working correctly.

 

 

 

Progress!

 

 

 

 

 

Now, all that’s left to do is hook them all up to the switch, do some testing, and tidy up all the wires. Not too hard of a project.
Test Results… 3S-GTE 4 EGT Temp Comparo

7/1/2001
4 Cyl EGT Comparo Info
75F – 60F in the shade
By: Pat Signorino and Shane Craddock

Shane’s Test Car (AKA Gecko2):
1991 MR2 Turbo 10PSI with 50 Trim wheel upgrade, and 1 Spal Fan on Stock Intercooler, 170 degree Stant Thermostat.

The car is not at the limit in terms of boost/heat. #2 and 3 cylinders do appear to be marginally hotter than 4 and 1. A simple EGT probe in the #3 cylinder is reccommended for all high HP Gen 1 US 3S-GTE’s. Warning temperature should be around 1550 degrees F. Once exceeded, things may already be at 1600F due to the slight lag inherent in EGT’s. If you see temps above 1600, you know that you are running lean, or something else is wrong with your engine. Keep in mind that these numbers may work for a pretty much stock car, but every car will be slightly different. Use this info at your own risk.

Hottest Cylinders in order 2,3,4,1 The difference between 1 and 2 is varying around 25 degrees F at 1400

Warm Idle Temps
Cyl
1 950
2 950
3 930
4 925

______________________________________
4500rpm 62mph 3rd gear constant
Cyl Temp
1 1405
2 1425
3 1410
4 1405

3000rpm 56mph 4th gear constant
Cyl Temp
1 1415
2 1435
3 1420
4 1410
_______________________________________
3rd gear runs max temp shift point 7,000
Cyl Temp
1 1550
2 1575
3 1550
4 1550

4th gear runs max temp shift point 6,200
Cyl Temp
1 1550
2 1585
3 1580 (1600 reached on one pull at 7000 rpm)
4 1580

Forward: We do NOT reccommend drilling into your ex. manifold with it on your car. Shane and Pat pulled the motor shortly after, and when Shane pulled the head, he found evidence that this procedure cannot be performed safely in this manner. The head had to be machined proffessionally to remove the damage where some of the shavings had been smashed repeatedly before exiting the engine. Apparently, some of the shavings were left in the manifold, and upon starting the engine, they were sucked in on a down stroke, and caused the damage. It has been said on the message board that you can do this procedure with the car running to fix the problem, but we think it would be to cramped, and way too HOT! See this link for more info Gecko 2 Head machine work 

4 EGT to 1 Switched Gauge Install

 

Recently, Shane Craddock installed 4 Westach EGT Probes in his Exaust Manifold, and hooked them up to a single switched Westach Gauge. The install was done with the manifold on the car, which normally is not recommended because metal shavings fall into the manifold, and can get stuck in the turbo, but the procedure can be done with the use of some simple tricks. EGT Preliminary test results at the bottom of the page. 

Here’s a pic of the special drill bit used to cut through the manifold.  

Show here are some pictures of ways to get the metal shavings out of the manifold. First was the use of a magnet tipped utility tool, and second a more difficult item to get, a vaccuum attatchment (only use when Girlfriend/Wife is not looking.  

 

 

Next you need to “tap” the holes you drill in order to give the EGT “bungs” something to screw into securely. We’ve learned to always use the special “tapping” oil to keep the tap working correctly.  

 

 

Progress!  

 

 

 

 

Now, all that’s left to do is hook them all up to the switch, do some testing, and tidy up all the wires. Not too hard of a project.
Test Results… 3S-GTE 4 EGT Temp Comparo

7/1/2001
4 Cyl EGT Comparo Info
75F – 60F in the shade
By: Pat Signorino and Shane Craddock

Shane’s Test Car (AKA Gecko2):
1991 MR2 Turbo 10PSI with 50 Trim wheel upgrade, and 1 Spal Fan on Stock Intercooler, 170 degree Stant Thermostat.

The car is not at the limit in terms of boost/heat. #2 and 3 cylinders do appear to be marginally hotter than 4 and 1. A simple EGT probe in the #3 cylinder is reccommended for all high HP Gen 1 US 3S-GTE’s. Warning temperature should be around 1550 degrees F. Once exceeded, things may already be at 1600F due to the slight lag inherent in EGT’s. If you see temps above 1600, you know that you are running lean, or something else is wrong with your engine. Keep in mind that these numbers may work for a pretty much stock car, but every car will be slightly different. Use this info at your own risk.

Hottest Cylinders in order 2,3,4,1 The difference between 1 and 2 is varying around 25 degrees F at 1400

Warm Idle Temps
Cyl
1 950
2 950
3 930
4 925

______________________________________
4500rpm 62mph 3rd gear constant
Cyl Temp
1 1405
2 1425
3 1410
4 1405

3000rpm 56mph 4th gear constant
Cyl Temp
1 1415
2 1435
3 1420
4 1410
_______________________________________
3rd gear runs max temp shift point 7,000
Cyl Temp
1 1550
2 1575
3 1550
4 1550

4th gear runs max temp shift point 6,200
Cyl Temp
1 1550
2 1585
3 1580 (1600 reached on one pull at 7000 rpm)
4 1580

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