DIY Exhaust Mod – Gain of 10+ HP!!!

[fredpayne]

Originally Posted by gilmanco

Why ghetto up your car just spend money on a real exhaust with proven HP gain?

I did, after I lost my drill bit in the muffler, I bought a set of Borlas

[MN 986]

Originally Posted by fredpayne

I did, after I lost my drill bit in the muffler, I bought a set of Borlas

I know how you feel. I almost lost my step drill bit also, so I would recommend caution when drilling (maybe don't have the drill go all the way in to the muffler/stop short of the last step).
I did this mod a few years ago and thought it was worth doing for a little more sound, mostly at idle. The added sound may have been a contributing factor in me wanting even more sound, and I eventually bought a FVD 'sound version' muffler and this year I am adding 'Che' secondary bypass pipes.
Think of the crios mod as a 'gateway' exhaust mod!

[fredpayne]

Originally Posted by MN 986

I know how you feel. I almost lost my step drill bit also, so I would recommend caution when drilling (maybe don't have the drill go all the way in to the muffler/stop short of the last step).
I did this mod a few years ago and thought it was worth doing for a little more sound, mostly at idle. The added sound may have been a contributing factor in me wanting even more sound, and I eventually bought a FVD 'sound version' muffler and this year I am adding 'Che' secondary bypass pipes.
Think of the crios mod as a 'gateway' exhaust mod!

I just wish I could get my drill bit our of the muffler, then I could sell them to a friend of mine, any ideas on how to do that?

[MN 986]

Originally Posted by fredpayne

I just wish I could get my drill bit our of the muffler, then I could sell them to a friend of mine, any ideas on how to do that?

Since it sounds like the muffler is off the car, you could probably cut a larger hole in the center section of the muffler (maybe on top/less visible) to get it out, then patch that hole. Page 1 of this post shows the inside view of the muffler, and I would guess that it is stuck in the middle section with no way to get it to other sections or out of the muffler without cutting it open.
Hopefully your (and almost my) misfortune can help others learn to be extra cautious with running the step drills all the way through the hole.
How do you like the Borla? I have read where some people say it is a little too loud, but these engines sound so good, that is hard to imagine.

[fredpayne]

Originally Posted by MN 986

Since it sounds like the muffler is off the car, you could probably cut a larger hole in the center section of the muffler (maybe on top/less visible) to get it out, then patch that hole. Page 1 of this post shows the inside view of the muffler, and I would guess that it is stuck in the middle section with no way to get it to other sections or out of the muffler without cutting it open.
Hopefully your (and almost my) misfortune can help others learn to be extra cautious with running the step drills all the way through the hole.
How do you like the Borla? I have read where some people say it is a little too loud, but these engines sound so good, that is hard to imagine.

I will probabaly get a cutting torch and do just that and then weld the piece back on, I tried some Billy Boats, now those were loud, too loud, a terrible drone in the car, couldn't even carry on a conversation, I got the Borla Sport Catback exhaust, not the fancy ones and I love them, perfect. It was Borla Part# 140115

[Crono0001]

Sorry for reviving this up, but I have a post that might help people.

I recorded my car revving it up before any DIY mods. Link here:
Pre Drill and De-Snork DIY mod for Porsche 986 - YouTube

Today I went ahead and tried drilling my exhaust. Because I didn't have a long enough drill bit, I could only mar the surface and create a small hole. No biggie, I took a file and hammered it in, and was going to file a gigantic hole... But after an hour of filing, I only got the hole to be 1 cm -_- Bigger holes to come.

I went into the car, turned on the engine, started revving up... No noticeable sound difference.

I also did the de-snork mod afterwards since I wasn't happy with the sound increase (or lack there-of). Pulled the grill apart, ripped out the snork.

I went into the car, turned on the engine, started revving up again... No noticeable sound difference.


HOWEVER, I did record an after video, link here:
Post Drill and De-Snork DIY mod for Porsche 986 - YouTube

And if you compare the two videos, there's a VERY noticeable sound difference. The second one is also growler and throatier. You'll also notice the idle growl that wasn't there before.

Moral of the story: DIY Drill and De-Snork mods won't make a huge sound difference... but it does. Watch videos and judge.

[MethosSVT]

Hi everyone, I have a few questions and I'm sorry if it is an old post but I wanted to know if anyone has dynoed or felt a torque loss in lower rmps? According to the cut-out muffler in the picture, the middle chamber doesn't comes in contact with the exhaust gasses right? It's hard to see but it seems to be a neutral chamber that has nothing to do with exahust flow, and if that's the case I don't think there should be any power loss, but then again there can be exhaust gas turbulence when the gas from the chamber and the pipe meet, creating thus more restriction. I'm just guessing here and probably that far out in the exhaust turbulence wouldn't be a problem, let me know if anyone has more info on this, have a great day everyone

[Crono0001]

Well, after driving around like this for a few weeks, I must say:

Wow, the sound is incredibly noticeable. Especially when you're driving down the street. It's a world of difference. Not too much of that loud ricer gurgle, but just enough of that throaty dark growl.

And no, I don't feel like the car has gotten any slower.

[truegearhead]

Has anyone actually done this on a weld on tip boxster? I tried but the angle of the plate and the distance makes it very difficult.

[hartids]

This sounds like an awesome free mod!! I'm gonna have to give this a crack tomorrow!! I had already put some time aside for my desnork and rear window restorer so I will now add this to the list!!!

Have peeps found that duct tape is the best way to prevent any scratching?...

[Spinnaker]

Originally Posted by truegearhead

Has anyone actually done this on a weld on tip boxster? I tried but the angle of the plate and the distance makes it very difficult.

2000 S with welded tips, see post #128. Didn't have much trouble at all.

"Have peeps found that duct tape is the best way to prevent any scratching?... "
The smooth surface of the extension did not leave any discernable marks on edge of the stainless steel tips.

[jesseborgelt]

Originally Posted by Spinnaker

2000 S with welded tips, see post #128. Didn't have much trouble at all.

"Have peeps found that duct tape is the best way to prevent any scratching?... "
The smooth surface of the extension did not leave any discernable marks on edge of the stainless steel tips.

I made a few attempts at this and walked away frustrated more than once. When I finally got it to work out the way I wanted it to, I was happy with the results. I had very realistic expectations for simply punching holes in a muffler and I like the sound better then stock.
My tips:
1) Take a shop rag fold it in half and line the inside of the tip with it while draping the excess over the outside of the tip and tape into place, both outside and inside. I used blue painters tape.
2) I got a cheap set of ridiculously long bits (like 30”) from Harbor Tool and Freight for under $15 for a set of 4. Using the smallest bit, I attempted to drill a hole which spun along the curve of the inside of the exhaust pipe to no avail. I peered into the pipe to see where I wanted the hole to be with the drill bit, then while maintaining my vision on the spot, removed the drill and replaced it with a long screwdriver. Bang the hell out of it because you must have a dent or small hole for the bit to catch on, otherwise you will get frustrated and the bit will spin everywhere.
3) With the hole punched, I set the bit in the hole and stepped up the sizes until I had a 3/4” hole carved out. I really had to put some effort into it, as I believe these are wood bits, but for $15 I don’t care about messing them up.
With the desnorkle accomplished at the same time, I felt like have done something good for the car.

[hartids]

Desnork and exhaust mod both achieved in under half an hour!! So so so worth it!! I really believe that the sound difference is instantly noticable... Not crazy loud but a definate deeper growl and at about 3200rpm through the lower gears it really buzzes nicely!! The only trouble I had while attempting both mods was getting the air intake off for the desnork... That thing really needed some brute force!! As soon as it was off no problems at all, hardly even had to pull the snorkel and it popped straight out!!

As for the exhaust mod I got a 12" hardened tip flat head and gave it a good few whacks right where I wanted the drill bit to take. Made a nice big dent which my 1/2" metal drillbit (12" long) grabbed hold of and went straight through with some heavy force. I went to do the same thing on the left pipe - gave the screwdriver a few whacks and actually punched straight through with the driver making about a 1/2" hole to match the first one!! Result - Didn't even need to get the drill out!!

The sound difference is clearly noticeable on my '98 2.5 man so I imagine it will sound really nice on the 3.2 S models with both mods. I'll upload a pic of where I punched the holes...

On another note has anyone ever considered tinting the rear plastic window? Mine is quite badly damaged and cloudy, can't really see a whole lot through it - tried a load of different specialist cleaning products but to no avail!! I know you can get pre-cut tint film for them but this is applied on the inside and I don't think it will cover up the damage.. I have some spray on tint but not sure if it will stick to the plastic? I'm up for giving anything a go to make it better as I can get a new window fitted for £195 if nothing works.

Any ideas?

Cheers all,
Hartids

[Idaho Red Rocket 3]

My window tint guy said it could be done but he would not guarantee it would stay on when the top is folded down. So I had him tint the wind-stop. Works great because whether the top is up or down, I always have a tinted rear window.

[hartids]

Thanks IRR3, that is definately an option for a tinted look at the back but it won't cover up the damage on my window which is what I am trying to achieve. I think i'm going to have to just put my hand in my pocket and pay out for a replacement window. I'd be up for giving anything else a go before I get the new one fitted if anyone has any ideas? I've tried cleaning and cleaning with specialist plastic window restorer which has worked on the clear sections but the cloudy patches just won't come out. Is there something more industrial I can try (maybe electric buffing) or any other way of staining or tinting the window to cover it up? I do have some headlight smoked tint spray which I am going to use on my front indicators (amber sections) but I think this will just come off with all the movement in the roof if I use it on the rear window. On that subject does anyone know if I need to sand the lights before applying the spray? The directions on the can say that they just need to be cleaned and oil free but I think maybe the spray will take better on a roughened surface?

Cheers all,
Hartids

[Michiganstar]

3yr old thread resurrection!!

I have just completed this mod on my '03 S and I'm really pleased with the results. The facelift exhaust/combo mean that you have to go in at quite an angle but its still easy enough. I had difficulty getting started with the large drill bit so I went with a smaller one to get the hole in place then went up a few sizes and on the 2nd drill and finally went with the large drill bit and it went through first time.
Really pleased with the throatier sound at idle and also there is a noticeable woofle at around 2800rpm. This is all achieved with no drone at highway speeds. Well worthwhile mod to do IMO.

[Homeboy981]

Cat Back System is a better responding and sounding way to go!

IF you have to do it, and when I was a newer member I did, use a metal punch from Lowes for shipping cement. I found a 1" version and made the holes within a few minutes. No stuck drill bits. For a couple hundred bucks you can chunk the "boat anchor" and get a really cool sounding exhaust…instead of a faint glimmer of one!

Anyone want a boat anchor with a Crios mod?

[Michiganstar]

Originally Posted by Homeboy981

Cat Back System is a better responding and sounding way to go!

IF you have to do it, and when I was a newer member I did, use a metal punch from Lowes for shipping cement. I found a 1" version and made the holes within a few minutes. No stuck drill bits. For a couple hundred bucks you can chunk the "boat anchor" and get a really cool sounding exhaust…instead of a faint glimmer of one!

Anyone want a boat anchor with a Crios mod?

I will no doubt go for a cat back system at some point but this mod is perfect for those who want a stop gap or dont want to lose the original parts.

[mangoman]

Originally Posted by Michiganstar

3yr old thread resurrection!!

I have just completed this mod on my '03 S and I'm really pleased with the results. The facelift exhaust/combo mean that you have to go in at quite an angle but its still easy enough. I had difficulty getting started with the large drill bit so I went with a smaller one to get the hole in place then went up a few sizes and on the 2nd drill and finally went with the large drill bit and it went through first time.
Really pleased with the throatier sound at idle and also there is a noticeable woofle at around 2800rpm. This is all achieved with no drone at highway speeds. Well worthwhile mod to do IMO.

What about the MOT emissions test? Did it pass?

[sub5kvm]

Originally Posted by Michiganstar

3yr old thread resurrection!!

I have just completed this mod on my '03 S and I'm really pleased with the results. The facelift exhaust/combo mean that you have to go in at quite an angle but its still easy enough. I had difficulty getting started with the large drill bit so I went with a smaller one to get the hole in place then went up a few sizes and on the 2nd drill and finally went with the large drill bit and it went through first time.
Really pleased with the throatier sound at idle and also there is a noticeable woofle at around 2800rpm. This is all achieved with no drone at highway speeds. Well worthwhile mod to do IMO.

Hi Michiganstar
My Boxster is a Facelift S also. Im looking to make this Mod, just interested to know if you drilled just through the end pipes only or through the other pipe in the middle chamber too (as in the picture shown by the green line)?

Ive already done the "de-snorkel" mod but looking for a little more grunt, without going down the by-pass or replacement route.

Im also from Reading too btw!

Cheers