New Exhaust

[Elmer Fudd]

Looking at the headers and connecting pipes on the 986 they need replacing so I've decided to go for a full stainless system, I don't want anything ridiculously loud or that drones on the motorway, it's a road car and wont be used on track, a few more ponies would be nice but not essential, with a budget of about £1500. I presume I would need to get an induction kit and a re-map as well? 

Any recommendations/advice very much appreciated 😁

[edc]

£1500 is a healthy budget. Plenty of options from Dansk, Supersprint, or save on the manifolds and get the eBay ones. You don't have to do he intake but if you are that way inclined add the 987 airbox, 996 plenum and 74mm throttle body. 

[edc]

Add sports cars too from expensive and branded to fairly cheap and disposable 200 cell ones from eBay. The eBay manifolds and cats are good value. 

[Ad_78]

+1 for the above, I have eBay manifolds & cats with Super Sprint back box, TB & plenum, got the 997 air box but not fitted yet as it’s a bit of a ball ache to do!

I have also remapped and done the de snorkel, it’s not extremely loud, but noticeably louder than a standard setup and really sounds great when your foots to the floor and people will certainly notice you shifting down the road, on light loads it’s not too bad. I don’t get any drowning from the system at all and much prefer the SS to the cheap Toyo sport box I had originally. 
 

Super Sprint were really helpful and although came from Italy was delivered really quickly. I did need some u pipes from cats (went for stainless) to back box and a set of reducers as SS back box has larger diaper pipe. 
 

I got my local garage to change the manifold as a couple of bolts were siezed and I didn’t want to damage anything, the rest I did myself and was pretty straight forward. 
other bonus is the full stainless system is a lot lighter than the existing system.

Save your old cats for MOT time unless you have a friendly MOT guy. 

[Elmer Fudd]

That's great, thanks Ad_78 😀

Do you have any links to the ebay parts? Can you get cats that will pass an mot on emissions?

Don't really want to change them over every year

[edc]

My eBay 200 cell cats pass the MOT 

Edited June 17, 2021 by edc

[Ad_78]

Hi Elmer Fudd

these are the parts I used:

decat pipes https://www.ebay.co.uk/itm/STAINLESS-EXHAUST-DE-CAT-DECAT-DOWNPIPE-FOR-PORSCHE-986-BOXSTER-2-5-2-7-3-2-96-/351731017264?_trksid=p2349624.m46890.l49286

You may want to look at some 200 cell cats though as per edc if you don’t want to change them for the MOT each year

Manifolds https://www.ebay.co.uk/itm/STAINLESS-EXHAUST-MANIFOLD-3-1-UNEQUAL-FOR-PORSCHE-BOXSTER-S-986-2-7-3-2-2-5-/150708724589?_trksid=p2349624.m46890.l49286

check these are the same shape as your existing as I believe 2.5/2.7 are a different shape, mines a 3.2 and these fitted great

Back box https://www.supersprint.com/ww-en/porsche-boxster-986-series/supersprint-performance-sport-exhaust-for-porsche-986-boxster-s-32i/rear-exhaust-right--left-racing-v7.aspx#!/

Tips https://www.supersprint.com/ww-en/porsche-boxster-986-series/supersprint-performance-sport-exhaust-for-porsche-986-boxster-s-32i/endpipe-kit-oo-90-v2.aspx#!/

U pipes https://www.ebay.co.uk/itm/STAINLESS-SPORT-EXHAUST-U-LINK-BEND-PIPES-FOR-PORSCHE-986-BOXSTER-S-2-5-3-2-/231021913463?_trksid=p2349624.m46890.l49286

I hope this helps.

Adam

[Elmer Fudd]

Well, I got ebay manifolds u link pipes and cats, and DesignTec back box from Design911 https://www.design911shop.com/Exhaust-Muffler---Silencer-with-Chrome-Tips-for-Porsche-Boxster-986/prod146655/?source=doofinder 

After wincing at the state of the manifold bolts I took her to my local indy to remove them and fit the exhaust, which proved to be rather expensive as he had to get a specialist in to remove all 12 bolts and fit heli coils.

Anyhoo, it's all done now and I've fitted a 74mm throttle body and induction kit, it now runs like a dog until it learns what's what, or I've had it remapped. I've ordered a couple of baffles for the back box because it drones, will let you know if they work! 🤪

 

[edc]

That designtek box is very similar if not identical to the eBay ones. 

As for the rough running it should not run rough. Did you do the throttle body reset? Have you ensured there are no leaks along the intake? 

[Elmer Fudd]

50 minutes ago, edc said:

That designtek box is very similar if not identical to the eBay ones. 

As for the rough running it should not run rough. Did you do the throttle body reset? Have you ensured there are no leaks along the intake? 

Yeah, I thought because it was sold by Design911 it would be better, obviously not 🙄

how do you do the reset?

Will check for leaks

 

[edc]

Ignition on, don't touch throttle, leave for circa 1 min until you hear the click of the throttle butterfly, ignition off then start car and drive. 

[Elmer Fudd]

25 minutes ago, edc said:

Ignition on, don't touch throttle, leave for circa 1 min until you hear the click of the throttle butterfly, ignition off then start car and drive. 

Thanks, just tried that but still rough, will look for leaks tomorrow with brake cleaner

[Elmer Fudd]

Ok, so I tested for leaks and there was one around the throttle body to plenum, sealed that and it is better but it's still running rough, the revs are going up and down on idle bringing on a CEL, and it's hesitating when you put some revs on. I plugged my Isoft in and it's coming up with a misfire on one bank, 4 5 6, don't know if it's trying to adapt to the new set up or somethings wrong, maybe I'll try putting the old intake system back on and see what happens.  

[edc]

I still think it's an air leak unless you really damaged the MAF. 

[Elmer Fudd]

Didn't touch the MAF, and it's a new one. Anyhoo, decided to clear the CEL and take her for a drive, after 20mins no CEL and no 'missing' and accelerating better than ever!

Maybe it needed a bit of time to adjust after sealing the air leak at the plenum.

I know the garage had to cut one of the lambda sensors out of the old exhaust because it was seized solid, maybe they damaged it 🤔 I'll replace both anyway. I'm just crossing my fingers all's well now🤞

[Terryg]

1 hour ago, Elmer Fudd said:

Didn't touch the MAF, and it's a new one. Anyhoo, decided to clear the CEL and take her for a drive, after 20mins no CEL and no 'missing' and accelerating better than ever!

Maybe it needed a bit of time to adjust after sealing the air leak at the plenum.

I know the garage had to cut one of the lambda sensors out of the old exhaust because it was seized solid, maybe they damaged it 🤔 I'll replace both anyway. I'm just crossing my fingers all's well now🤞

I had to cut through the threaded sleeves that held my Lambda sensors in, I damaged one and replaced it after reading up a bit about them, in my case the car felt much better immediately on start up. I did manifolds and 200 cell cats.

[Elmer Fudd]

Well the baffles arrived yesterday and I put them in, firstly without the end caps, and then with, it kinda took the edge off the droning but it was still there, and it started whistling a bit like a two stroke bike when slowing down in town 🤣

With the end caps in the whistling stopped but there was a small amount of vibration instead 🙄 and it was still droning, not as bad, but still too much for my liking. So I'm going to change the back box, any recommendations? I was thinking along the lines of the quieter Dansk one 

https://www.design911shop.com/Exhaust-Muffler---Silencer-Twin-Outlet-Dansk-94310S-1620602800/prod1611/

 

[jonogt6]

1 hour ago, Elmer Fudd said:

Well the baffles arrived yesterday and I put them in, firstly without the end caps, and then with, it kinda took the edge off the droning but it was still there, and it started whistling a bit like a two stroke bike when slowing down in town 🤣

With the end caps in the whistling stopped but there was a small amount of vibration instead 🙄 and it was still droning, not as bad, but still too much for my liking. So I'm going to change the back box, any recommendations? I was thinking along the lines of the quieter Dansk one 

https://www.design911shop.com/Exhaust-Muffler---Silencer-Twin-Outlet-Dansk-94310S-1620602800/prod1611/

 

The baffles.work best inserted in to the silencer after the u bends-at least that's my experience anyway. This eliminates the odd noises that you've mentioned and also hides the baffles from sight.

[Elmer Fudd]

10 hours ago, jonogt6 said:

The baffles.work best inserted in to the silencer after the u bends-at least that's my experience anyway. This eliminates the odd noises that you've mentioned and also hides the baffles from sight.

Does it eliminate the droning?

[brillomaster]

12 hours ago, Elmer Fudd said:

Well the baffles arrived yesterday and I put them in, firstly without the end caps, and then with, it kinda took the edge off the droning but it was still there, and it started whistling a bit like a two stroke bike when slowing down in town 🤣

With the end caps in the whistling stopped but there was a small amount of vibration instead 🙄 and it was still droning, not as bad, but still too much for my liking. So I'm going to change the back box, any recommendations? I was thinking along the lines of the quieter Dansk one 

https://www.design911shop.com/Exhaust-Muffler---Silencer-Twin-Outlet-Dansk-94310S-1620602800/prod1611/

 

funny you should mention that... i also tried to baffle an ebay dronemaster special exhaust and while drone was removed, so was most of the glorious flat 6 noise. and yep, terrible whistling noise with the roof down. so they came straight back out again. I've kept them in case i'm too noisy on a trackday, but its very unlikely i'll put them in for road driving.

One thing i have found after running with the ebay backboxes a while now is that they do seem to be quietening down - the drone immediately after fitting was horrendous but now after a few hundred miles its definitely mellowed. If you like the tone over 3000rpm i'd perhaps stick with them for a bit longer - if after another month or two you're still not liking them then they'll still be worth the same secondhand. I paid £120 for mine, knowing that i could get it new for £170.