12:05 Garage- ’70 Duster build
I'm sure that most people that follow along here know I have the full TTI exhaust. When I purchased the exhaust kit, I wasn't thrilled with the turbo mufflers they supply, but didn't want to fight with making something else work on a system that was designed around those mufflers. As I'm sure most know, turbo mufflers are very quiet. Heck, you can't even hear it running in all of the videos I have of my car on the autocross! I also knew these mufflers are the largest HP stealers of any muffler on the market. I've always liked Borla mufflers, I had their straight through bullet mufflers on the car when I used to drag race. I purchased a set of their 2.5" Pro XS mufflers with offset inlet and center outlet, just like the turbo mufflers. The offset distance was about 1" difference, but fortunately, I was able to manipulate the tailpipes enough to make them work without reworking the X-pipe.
I didn't take any dB readings with my phone, but at idle, it sounds almost exactly the same. It may be a touch louder, but it is negligible. I did immediately notice throttle response was improved. Slower speed driving also seems to be very similar and wide open throttle may be a little louder, but who cares at WOT. Steady state cruising at highway speeds is actually quieter. I can't even hear the engine at cruising speed. Now for the good stuff. The increase of power is crazy. The motor revs way quicker and pulls much harder through the upper RPM range. I seriously cannot believe the difference. I originally thought it was all in my head until a found a guy on youtube that changed out some chambered mufflers to the Borlas like I have. He had what I assume is a stockish big block and 3" exhaust, but the same principle applies. On his first drive, he also commented on throttle response and how much stronger it felt, but didn't know if it was mental or real. He followed it up with a trip to the drag strip. He had very well documented time slips including density altitude, temp, etc. his car went .27 quicker and 2MPH faster with just a muffler change in worse air! After seeing this, perhaps the improvement I feel isn't mental.
So moral of the story is, don't use turbo mufflers! For very similar sound (and better at cruise) why not get a better muffler and keep all the HP your motor is making. Sure a pair of turbo mufflers are probably $150 cheaper than the Borlas I bought, but where are you going to get this much increase in power for $150? I don't even understand why TTI sells those things! The turbo mufflers went right were they belong, in the trash!
I'm sure that most people that follow along here know I have the full TTI exhaust. When I purchased the exhaust kit, I wasn't thrilled with the turbo mufflers they supply, but didn't want to fight with making something else work on a system that was designed around those mufflers. As I'm sure most know, turbo mufflers are very quiet. Heck, you can't even hear it running in all of the videos I have of my car on the autocross! I also knew these mufflers are the largest HP stealers of any muffler on the market. I've always liked Borla mufflers, I had their straight through bullet mufflers on the car when I used to drag race. I purchased a set of their 2.5" Pro XS mufflers with offset inlet and center outlet, just like the turbo mufflers. The offset distance was about 1" difference, but fortunately, I was able to manipulate the tailpipes enough to make them work without reworking the X-pipe.
I didn't take any dB readings with my phone, but at idle, it sounds almost exactly the same. It may be a touch louder, but it is negligible. I did immediately notice throttle response was improved. Slower speed driving also seems to be very similar and wide open throttle may be a little louder, but who cares at WOT. Steady state cruising at highway speeds is actually quieter. I can't even hear the engine at cruising speed. Now for the good stuff. The increase of power is crazy. The motor revs way quicker and pulls much harder through the upper RPM range. I seriously cannot believe the difference. I originally thought it was all in my head until a found a guy on youtube that changed out some chambered mufflers to the Borlas like I have. He had what I assume is a stockish big block and 3" exhaust, but the same principle applies. On his first drive, he also commented on throttle response and how much stronger it felt, but didn't know if it was mental or real. He followed it up with a trip to the drag strip. He had very well documented time slips including density altitude, temp, etc. his car went .27 quicker and 2MPH faster with just a muffler change in worse air! After seeing this, perhaps the improvement I feel isn't mental.
So moral of the story is, don't use turbo mufflers! For very similar sound (and better at cruise) why not get a better muffler and keep all the HP your motor is making. Sure a pair of turbo mufflers are probably $150 cheaper than the Borlas I bought, but where are you going to get this much increase in power for $150? I don't even understand why TTI sells those things! The turbo mufflers went right were they belong, in the trash!