I'm curious about these Spiral Turbo Exhaust inserts when it comes to mounting them right after the headers. The only reviews I can find are for Corvettes and Cobras with side pipes, or for full size front engine cars and trucks. I like the idea of having what looks like a straight pipe vs a glass pack muffler. Has anyone run them before? How do they do with sound reduction with this type of exhaust? I want my car a little loud, but not obnoxious.
Yes, My GT40 has those inside round mufflers. One for each side of the engine. They are very loud! My 350Hp 302 made 114DB at thunder hill in California and I had to add some 90-degree turns so that the sound was directed away from the sensor on the side of the track.They had the metering sensor right behind the pit wall and above the level of the wall. That put the sensor at a right angle and about 1-11/2 car width from the exhaust pipes. The position on the front straight was right where the cars were at maximum speed at the end of the fastest straight. I was at about 140MPH, full beans, approx 5000revs.
So how loud is it though? Really fucking loud!!!!! It gets everyone's attention when I start it up. But it can be made to behave if revs are kept down and with very little throttle opening. Inside the car at freeway cruise speeds is fine.............until you floor it........then everyone around you snaps their heads off turning their heads to see what the hell is THAT!
Those things don't make good mufflers..............not really. I am forever going to make a muffler out of one of these if I ever get to it.
Thanks for the reply Howard, and the laugh. Guess I need to try and find something I like the looks of that will actually take the bark out of the exhaust.
I used them on my Pantera it has 3" outlets with small magnaflow mufflers and using the inserts coupled with the cones, plus 90 degree bends I was able to get below 103 dB at Thunderhill without a bunch of reworking the exhaust system. I guess it depends where you are at and how much dB reduction is required.
I decided to make a video showing how loud these things actually are.
Key takeaways for me were: The discs make a bigger difference in idle sound reduction than running 2 of the baffles. Also I feel that full throttle is the same no matter how you have them. Open headers yielded the same decibel levels as with the baffles installed when I revved it.
As of now, I plan to keep 1 set installed with the discs welded in.
I used to run those mufflers in stock cars. They were made by a company called Lobak. I believe they were bought out by Moroso.
You can perforate the core pipe and then weld a washer into the output side of that core and it significantly reduces the dB readings. Of course the resulting restriction kills off a few HP on the top end, but that might be worth it to you if you get tired of the drone in the exhaust. Some guys have even mounted that washer on a bolt that goes through the pipe - making it look like a throttle butterfly.
The car sounds glorious though!!!
