Dinan Valved Exhausts for the Toyota GR Supra

[Foogazzi]

Any MT owners get drone around 3-4K rpm?

Stock exhaust has a drone at 3-4k

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[decodeddiesel]

Has anyone taken any legit SPL readings with a meter?

I'm very interested in this exhaust for my car, however I regularly drive a track with an 88 dB exhaust limit and I want to be sure valve closed would not get me black flagged.

@Dinan_Engineering

 

[Dinan_Engineering]

@Dinan_Engineering

Unfortunately we never did any dB measurements on this particular exhaust (development was during a time we were in transition and upgrading sound testing equipment/software). All of the development Supra's are no longer at our facility so can't do a measurement now either. That said, just based off of relatively recent measurements on the G87 M2 I would say with pretty good confidence that the Supra would likely eclipse 88 dB even with the valve closed. Even stock the M2 measures around 100dB at cruise with valves closed and the Supra exhaust is not much quieter -- arguably louder when in it actually.

 

[decodeddiesel]

Unfortunately we never did any dB measurements on this particular exhaust (development was during a time we were in transition and upgrading sound testing equipment/software). All of the development Supra's are no longer at our facility so can't do a measurement now either. That said, just based off of relatively recent measurements on the G87 M2 I would say with pretty good confidence that the Supra would likely eclipse 88 dB even with the valve closed. Even stock the M2 measures around 100dB at cruise with valves closed and the Supra exhaust is not much quieter -- arguably louder when in it actually.

Thank you for your candor. That's too bad, but not necessarily a show stopper. Lime Rock is a PITA about their sound restrictions.

I would love to have this out on Watkins Glen or another track with no sound limits.

 

[razorlab]

Thank you for your candor. That's too bad, but not necessarily a show stopper. Lime Rock is a PITA about their sound restrictions.

I would love to have this out on Watkins Glen or another track with no sound limits.

Just remember the way these are usually measured are different than how race tracks measure it. The measurement you usually see is a couple feet from the exhaust and racetracks are probably 50+ ft.

I would have been blackflagged LOOOONNNNNGGG ago at Lime Rock if they measured it right at the exhaust.

 

[decodeddiesel]

Just remember the way these are usually measured are different than how race tracks measure it. The measurement you usually see is a couple feet from the exhaust and racetracks are probably 50+ ft.

I would have been blackflagged LOOOONNNNNGGG ago at Lime Rock if they measured it right at the exhaust.

Do you actually know how they measure at LRP? How it's weighted and where it's measured from?

It just blows my mind how loud some cars are there and no one gets black flagged despite the warnings like everywhere. ?

The stock bangs and burbles on a bone stock 2020 are very likely over 100 dBA when measured from 2 meters away from the exhaust at 45°.

@Dinan_Engineering can you give some details on the testing method you used for the M2?

 

[razorlab]

Do you actually know how they measure at LRP? How it's weighted and where it's measured from?

It just blows my mind how loud some cars are there and no one gets black flagged despite the warnings like everywhere. ?

The stock bangs and burbles on a bone stock 2020 are very likely over 100 dBA when measured from 2 meters away from the exhaust at 45°.

No idea and nobody will say for obvious reasons. I do think if the GT350’s and GT4’s don’t blow sound, we are probably good unless full straight piped.

 

[garudathree]

My stock RS blew sound before, had to short shift

 

[decodeddiesel]

No idea and nobody will say for obvious reasons. I do think if the GT350’s and GT4’s don’t blow sound, we are probably good unless full straight piped.

I think you're right. The inverse square law is on our side too. For every doubling of distance from a source the sound will lose 6 dB.

 

[decodeddiesel]

My stock RS blew sound before, had to short shift

Damn it dude! ??

It's just crazy when you hear a Supra in comparison to the other cars on track. The factory exhaust sounds good with a downpipe, but it's so damn quiet.

 

[razorlab]

My stock RS blew sound before, had to short shift

The RS seems wayyyy louder than a GT4 and GT350

 

[razorlab]

Damn it dude! ??

It's just crazy when you hear a Supra in comparison to the other cars on track. The factory exhaust sounds good with a downpipe, but it's so damn quiet.

Don’t make me bring out the yazzz flute gif again!

 

[RyanA90]

Its not loud at all! Reving and driving home after work (in Mexico of course).

 

[RyanA90]

Any MT owners get drone around 3-4K rpm?

Its about 2k for me.

 

[Meraki Autoworks]

We have these in stock if anyone is interested.

-Josh

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