thouths on a 997 GT3 muffler on smaller displacent air cooled motor?

[jmz]

I've seen lots of examples of the GT3 mufflers put on 3.6+ motors in early cars and the sound is awesome. I have one in my garage but my car has a measly 3.0...it's a built 3.0 with Mod S cams, twin plug but only about 9.5:1 C.R.

Anyone run one on a smaller engine like mine or know if they would work well or not?

[Fabspeed Motorsport]

Jay,

Hard to say without knowing what header design you will be running. In my experience its the headers/manifolds which give best gains in HP and TQ. We ran a GT3 Center with factory manifolds on a stock 3.0SC with little gains. That may change in respect to your modifications. Dyno#'s are the tell all... It should run fine but not sure if it will contribute anything but sound.

[jmz]

I was thinking of using a set of SSI heat exchangers that I would modify to work with GT3 Muff. I like having defrost...

I'll try to do before after dyno runs if I go this route. If I don't lose any horsepower and if I like the sound I'd consider it a win.

[mb911]

Are you planning to make the gt3 muffler active? If so then as long as the header is optimized for your application then it will work just fine.

[911pcars]

I’m guessing sourcing one of these is for the sonic effect? I’m good with that.

However, unless the new muffler is too restrictive (the GT3 muffler probably isn’t), I dont expect mufflers to produce significant power (maybe negligible), especially in lieu of the expense in sourcing one.

Sherwood

[jmz]

Originally Posted by mb911

Are you planning to make the gt3 muffler active? If so then as long as the header is optimized for your application then it will work just fine.

I haven't fully thought through it yet. I was thinking I'd have to cap off two of the inlets.

How would you go about it Ben and do you think it is worth the effort? I was thinking it would be a fun "science project" but would hope it was one with positive outcomes.

Cheers,

Jay

[jmz]

Originally Posted by 911pcars

I’m guessing sourcing one of these is for the sonic effect? I’m good with that.

However, unless the new muffler is too restrictive (the GT3 muffler probably isn’t), I dont expect mufflers to produce significant power (maybe negligible), especially in lieu of the expense in sourcing one.

Sherwood

Yes, going after a good exhaust note but don't want to hurt power either. I have the GT3 center muffler already so just need to decide if I want to cut the tails off the SSIs and have a connector piece made to mate up to the GT3 muff.

[Bill Verburg]

Originally Posted by jmz

I've seen lots of examples of the GT3 mufflers put on 3.6+ motors in early cars and the sound is awesome. I have one in my garage but my car has a measly 3.0...it's a built 3.0 with Mod S cams, twin plug but only about 9.5:1 C.R.

Anyone run one on a smaller engine like mine or know if they would work well or not?

You aren't going to hurt the torque curve. Pipes need to be sized proportionally to the expected flow, but a muffler servers a different purpose and works differently. For a muffler generally there is no such thing as too big, You'd probably want to just use the upper inlet and cap off the lower one

[mb911]

Originally Posted by jmz

I haven't fully thought through it yet. I was thinking I'd have to cap off two of the inlets.

How would you go about it Ben and do you think it is worth the effort? I was thinking it would be a fun "science project" but would hope it was one with positive outcomes.

Cheers,

Jay

Jay,


I would do it. It's a cool project. I thought about doing that on my 914-6 project..

[mikedsilva]

Scroll down.. this company makes some cool looking mufflers.
Porsche 911 (64-73) Exhaust – TT Exhausts

[911pcars]

Somewhere in the following link is an exhaust level comparing several loud Porsche’s (RS, RSR, 928, etc.). They recorded and charted their results with what looks like a proper SPL (dB) meter.

https://m.youtube.com/results?search_query=Porsche+exhaust+comparison

However, some readers might attempt to use the volume control on their phone, laptop or desktop speaker(s) to understand what they’re trying to convey. Unfortunately, trying to replicate 100-126 dBs might cause most speaker cones to hemorrhage, and most will avoid equipment and/or ear damage and not understand the exhaust note as recorded.

For more accurate referencing, suggest reproducing using a proper sound system with one of several free/low cost dB/SPL meter apps. Then, one can more accurately quantify the perceived loudness of an exhaust system instead of relying on terms such as, “loud”, “sporty”, “racy”, “aggressive”, “knarly” and “*****in”.

Some may have to demo to the spouse for ultimate approval 😬

[spyerx]

Originally Posted by Bill Verburg

You aren't going to hurt the torque curve. Pipes need to be sized proportionally to the expected flow, but a muffler servers a different purpose and works differently. For a muffler generally there is no such thing as too big, You'd probably want to just use the upper inlet and cap off the lower one

ON the GT3 muffler the lower holes are high flow with a simple 'gap' baffle. On my 997RS when the valves open it directs all flow to the lower holes. The top holes are the 'quiet' holes. And are much more restrictive.

So yeah if you want it quieter use the top holes.

[Bill Verburg]

Originally Posted by spyerx

ON the GT3 muffler the lower holes are high flow with a simple 'gap' baffle. On my 997RS when the valves open it directs all flow to the lower holes. The top holes are the 'quiet' holes. And are much more restrictive.

So yeah if you want it quieter use the top holes.

I understand that, that's why I suggested capping the the lower inlets, the upper will be more than sufficient and quieter.

[Ayles]

Originally Posted by jmz

Yes, going after a good exhaust note but don't want to hurt power either. I have the GT3 center muffler already so just need to decide if I want to cut the tails off the SSIs and have a connector piece made to mate up to the GT3 muff.

I was googling this same thing last night... great timing!

How do you plan on mounting the muffler to the engine carrier muffler bracket?

Also seems to be a wide range of asking prices, any idea what the actual market is on these?

[clutch-monkey]

Originally Posted by mikedsilva

Scroll down.. this company makes some cool looking mufflers.

800 pounds for a muffler plus shipping..

[ian c2]

Originally Posted by 911pcars

Somewhere in the following link is an exhaust level comparing several loud Porsche’s (RS, RSR, 928, etc.). They recorded and charted their results with what looks like a proper SPL (dB) meter.

https://m.youtube.com/results?search_query=Porsche+exhaust+comparison

However, some readers might attempt to use the volume control on their phone, laptop or desktop speaker(s) to understand what they’re trying to convey. Unfortunately, trying to replicate 100-126 dBs might cause most speaker cones to hemorrhage, and most will avoid equipment and/or ear damage and not understand the exhaust note as recorded.

For more accurate referencing, suggest reproducing using a proper sound system with one of several free/low cost dB/SPL meter apps. Then, one can more accurately quantify the perceived loudness of an exhaust system instead of relying on terms such as, “loud”, “sporty”, “racy”, “aggressive”, “knarly” and “*****in”.

Some may have to demo to the spouse for ultimate approval 😬

All this post needs is an attachment big enough to break the internet and it woood be awesome !!

[mikedsilva]

Originally Posted by clutch-monkey

800 pounds for a muffler plus shipping..

cheap huh?

[clutch-monkey]

Originally Posted by mikedsilva

cheap huh?

i think i'll get one made haha.

[famoroso]

I'm considering something similar for a 3.4 build. Haven't decided on headers yet (seems like many go with B&B long tubes as per the attached). I would definitely want to preserve the ability to switch between the upper and lower flow paths though.

[mb911]

Turbo Thomas TT has come along way since they started making porsche exhaust.. Its hard for me to get over the flat turbo muffler look like a muscle car.

I still have not seen one in front of me.. I remember when I started m&k how mad I was that they had copied my designs. Now though they have their own design.