DIY Exhaust Mod – Gain of 10+ HP!!!

[tuneme]

Originally Posted by jgaude

I'm bummed... I just did the mod on my '01 S, with 1/2" holes.. no sound difference at all! :-(

..Joe

Shure you angled the holes like the thread said? otherwise i noticed a big difference when i did mine

[crios]

Originally Posted by carguy

So who's gonna make the before and after videos?? Outside car and inside car..

Ah, you did not read from page 1? Take a look at my videos:

http://www.youtube.com/user/CRIOS123

[jgaude]

Originally Posted by tuneme

Shure you angled the holes like the thread said? otherwise i noticed a big difference when i did mine

You are probably correct. I have non-removable tips, and had to use a 12" bit.. so my angle was very shallow and so my holes are further back then I think they should be. But, looking at the cutaway picture, it looks like any hole into the middle chamber should work...

After driving it today... there is a difference. Not much of one, but there is a difference. I think I need a bigger drill! :-)

...Joe

[carguy]

Originally Posted by crios

Ah, you did not read from page 1? Take a look at my videos:

http://www.youtube.com/user/CRIOS123

Don't know how I missed that...thanks!

[jaykay]

Wow has anybody come up with some wood vee block jigs for fixed tips yet?

[Stroked & Blown]

Originally Posted by jaykay

Wow has anybody come up with some wood vee block jigs for fixed tips yet?

I was having a tough time getting the angle with my fixed tip 98 and a 6" long bit. I stopped before I caused any damage.

Any fixed tip guys have recommendations or pics of how they did it?

[Stroked & Blown]

Bought a long 1/2" drill bit over the weekend and tried again, but I still can't seem to get any bite on the side of the pipe. The angle at which the bit contacts the pipe with the tip on is so shallow that it is just barely milling the surface of the pipe with the side of the bit.

Can anyone that did this with a fixed tip post some more details?

[Spinnaker]

Just lightened my muffler with this DIY mod. Took me long enough to get around to it, saw the thread when it first came out.
Drilled ¾" holes in my fixed tip 2000S using a stepped drill bit I got at Harbor Freight. I've seen these bits at Home Depot also, I think they were Dewalt brand. The small tip of the step drill doesn't have the tendancy to wander around as much as a full size bit and I didn't have a lot of trouble getting it to start drilling at the bend in the pipe. I mounted the bit in an Irwin 12" drill bit extension and angled the bit into the pipe, letting the extension ride on the inner edge of the exhaust tip to brace it. The smooth shank of the extension didn't even leave any discernably marks on the edge of the tip. The only hassle was I had to grind the shank of the bit round to fit into the extension, since it came as a hex shape. The only mistake I made was to angle the bit upwards when I was drilling. The bit ran into the pipe that connects the center chamber to the end chamber after I broke through the first pipe. Luckily, the bit is short enough that was still able to finish drilling without drilling into the other pipe behind it. I put some scratches on the inner pipe, but unless you get down on the ground with a flashlight, look into the exhaust tips and through the first holes, you'll never see them. So in hindsight, keep the drill bit level. Oh, it was fun sweeping all the stainless steel chips from the driveway the first time I started it up after the drilling. They come spraying out and make a weird noise as they come out the tail pipe. At first I thought I had done something wrong because the sound was so strange. The metal chips must make a swirling/rattling noise until they get blown out. A good reason to take the car out to blow out the muffler with some high RPM's.
Just like the previous posts, the sound is throatier and a little more burblier (sp?) at lower RPMS and I notice it some when accelerating and deaccelerating more than before. Other than that, the perma-grin gets even bigger. Sound more like a sports car now.

[greenerob]

Just did this hack to my 1998 Boxster Base. I of course have the welded tips.

I took a long screw driver.

Angled it as much as possible towards the outside of the car so that the tip was on the inside of the pipes.

I held the angle as hard as I could so it wouldn't slip inside the pipe.

I hit it with a hammer a few times to create a hole.

I drilled the hole until it was all the way through being careful to not go any further inside then a complete hole.

The sound is noticably throatier at low RPMs, but there is no difference at the higher RPMs probably due to the much higher flow.

Recommended and easy.

[tuanle16]

i am having the same problem as some others. can't get the angle because of the welded tip. the bit just slides down the pipe. any other suggestions. also, looking at the original picture...am i suppose to drill through two pipes? ie.obviously, drill a hole into the last out going pipe, but then does that hole just enter into the chamber? or is it suppose to enter the entering pipe? refer to the original picture. the "bypass" as outline on the picture with green arrow, shows pipe1 to pipe2. thanks. is there a specific drill bit i should buy? i bought one that was extra long and "masonite" bit, but it didn't work.

[Boxtaboy]

FWIW, someone did this to their 02S at a local Boxster work on cars day (drilled 2 holes with a long drill bit), and afterwards, I could hear no difference. You sure it's not all in your mind?

[greenerob]

Originally Posted by tuanle16

i am having the same problem as some others. can't get the angle because of the welded tip. the bit just slides down the pipe. any other suggestions. also, looking at the original picture...am i suppose to drill through two pipes? ie.obviously, drill a hole into the last out going pipe, but then does that hole just enter into the chamber? or is it suppose to enter the entering pipe? refer to the original picture. the "bypass" as outline on the picture with green arrow, shows pipe1 to pipe2. thanks. is there a specific drill bit i should buy? i bought one that was extra long and "masonite" bit, but it didn't work.

tuanle,

Please read my post that was posted just before yours. Follow my EXACT description and you will have no problem.
Also, you are not drilling into cement, so ditch the masonry bit and get a bit made for metal!!

[tuanle16]

greenerob,

thanks. when i posted, i didn't see yours. sorry. newbie. as for the bit, couldn't find it at home depot. that was the only one that was long enough. i'll try a different home depot. not much selection at local one. were you able to drill with cordless drill or did you have to get a corded drill? electric ones have more power right? also, instead of crios recommendation of drilling towards midline, you punch your hole away from midline, right? will try again.

[greenerob]

Originally Posted by tuanle16

greenerob,

thanks. when i posted, i didn't see yours. sorry. newbie. as for the bit, couldn't find it at home depot. that was the only one that was long enough. i'll try a different home depot. not much selection at local one. were you able to drill with cordless drill or did you have to get a corded drill? electric ones have more power right? also, instead of crios recommendation of drilling towards midline, you punch your hole away from midline, right? will try again.

I drilled with a cordless drill. It probably took a little longer though. As far as the angle of the I held the screw drivfer as far towards the center as the tips would allow and then waked it a couple times. I used a long and thick flat headed screw driver.

[davey]

On the early welded single exit boxes could you not just drill one big hole between the two outlets with a tank cutter? It would have exactly the same affect.

[tamarsha]

Originally Posted by davey

On the early welded single exit boxes could you not just drill one big hole between the two outlets with a tank cutter? It would have exactly the same affect.

Sounds logical to me. The whole point is to tap into that center chamber.

[jazzhound]

Originally Posted by Boxtaboy

FWIW, someone did this to their 02S at a local Boxster work on cars day (drilled 2 holes with a long drill bit), and afterwards, I could hear no difference. You sure it's not all in your mind?

I notice a difference although sutle. feels like I gained a few hps also!

[Boxtaboy]

Originally Posted by jazzhound

I notice a difference although sutle. feels like I gained a few hps also!

Must be the brake bleed! Glad to hear you noticed a difference. Will have to get Gundo to drill bigger holes next time!

[SoK]

yeah i don't know how you guys are doing this on the welded tip models, i'm just tearing up the tip now.

Tried punching a small hole to start, can't seem to get it with a long flat-head or an actual punch at the end of a long file I have. any other suggestions?


edit: got it, just used the large flat head screwdriver and a hammer and punched out a 7/8" x 3/8" rectangle. Couldn't get anywhere with a drill. Took about 15 minutes once I figured out the technique. Haven't started it up, we'll see how it sounds tomorrow, if I can notice a difference.

edit: There is a slight difference in noise level, but i do like it. It's really pretty tough to notice, which is good. no drone whatsoever.

just a note, don't forget to take the tape off the exhaust tip before you leave for the day...

[mcfly777]

I tried to do it over the weekend, but just couldn't. Tried first with the drill, but it wouldn't catch. Also tried with a flat screwdriver, no good, it just keeps dancing around...

Don't know what to do next.

mcfly.