Hi all,
I took some noise level readings while driving the Jeep to see what contributed the most and least to the noise level. Would you be able to do the same so we can quantify and compare?
Test vehicle: 1998 4.0 TJ with full doors and factory hard top.
Phone: Samsung S8
1. 70 mph, freeway, under power: 74/75 dB
2. 70 mph freeway, coasting in neutral:
69 dB
I am deducing that engine under power adds extra 5dB.
3. 35 mph on the street: 70dB
Wind noise from going 35 mph vs 70 mph 4, 5 dB.
4. Stopped, idle: 60 dB.
5. Engine off: 39 dB
Wow, the largest contributor in my configuration is the motor!!! Not the wind. It adds 20 dB.
Conclusions:
Motor sound is the largest contributor at 20dB.
Idle motor vs under normal power +5dB
Wind noise increases liniearly and at +10dB at 70 mph calculates to +0.14dB/mi.
Your biggest concern is the motor so engine compartment and firewall sound proofing should have the largest impact.
What are your numbers?
I took some noise level readings while driving the Jeep to see what contributed the most and least to the noise level. Would you be able to do the same so we can quantify and compare?
Test vehicle: 1998 4.0 TJ with full doors and factory hard top.
Phone: Samsung S8
1. 70 mph, freeway, under power: 74/75 dB
2. 70 mph freeway, coasting in neutral:
69 dB
I am deducing that engine under power adds extra 5dB.
3. 35 mph on the street: 70dB
Wind noise from going 35 mph vs 70 mph 4, 5 dB.
4. Stopped, idle: 60 dB.
5. Engine off: 39 dB
Wow, the largest contributor in my configuration is the motor!!! Not the wind. It adds 20 dB.
Conclusions:
Motor sound is the largest contributor at 20dB.
Idle motor vs under normal power +5dB
Wind noise increases liniearly and at +10dB at 70 mph calculates to +0.14dB/mi.
Your biggest concern is the motor so engine compartment and firewall sound proofing should have the largest impact.
What are your numbers?
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