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YOUR RESEARCHAdded Topgear Headers
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Replace those two very long clamp bolts
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Suggestion
I would replace those two very long clamp bolts for shorter bolts.
Leading evidence: 'Replace those two very long clamp bolts' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Replace those two very long clamp bolts' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Suggestion · Original poster
Many of the custom exhausts made for these use stainless steel.
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Suggestion · Original poster
My other hobby is VW Vanagons using Subaru engines.
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After recently swapping my cats out for Topgear brand 200 cell cats I decided to give their headers a try.
See previous post here...
https://rennlist.com/forums/996-foru...tle-dough.html
I was very satisfied with the quality of the cats. The price was decent. Shipping from the UK was with in a weeks time. Installation and fit went with no issues so I decided to give their headers a try.
Same thing on shipping, only about a week to arrive at my door via DHL.
It took about an hour to remove the stock and install the new headers. The quality once again there is nothing to complain about from what I see. Only one thing caught my attention after the install was complete. One of the header tubes on the passenger side is just barely touching one of the tubes of the muffler bracket. I'll address that a little later, even though I don't expect it to be anything of a problem.
I've started the car, it sounds great but have yet to take it out on the road. Maybe I will this week end if they don't re-salt the roads after our last good rain yesterday.
, it sounds great but have yet to take it out on the road. Maybe I will this week end if they don't re-salt the roads after our last good rain yesterday.
The original stock mufflers had some seam rot. I trashed them already.
Someone on this forum gave me a good pair of stock mufflers which I added bypasses and are on the car now.
Looks awesome! After a drive I would like to know how they sound, because they look really good. I would replace those two very long clamp bolts for shorter bolts. Looks like they are almost touching the block. And how difficult a time did you have with the existing manifold bolts?
Yeah, I could swap out or cut those long clamp bolts, but they aren't close to touching anything. The engine was just done over by FSI less than a year and about 3500 miles ago, so no problem with removing the header bolts. FSI did a Stage 1 3.6 with IMS Solution.
those look great...maybe take them off and grind 1/4 inch of the muffler bracket and that should fix it.. btw i have a set of topgear uk 200 cell cats i was going to sell but now im not sure after seen them on..
I am interested to know what the performance difference is - I have some fabspeed headers in a box ready to install, and I want to get an x-pipe as well. Those pipes you have are a more reasonable alternative price wise...
I am also in Mass, why did they salt the roads again!!! Arggghhhhh
I did drive the car a bit after installing the 200 cell cats and modded mufflers. It was a noticeable seat of the pants improvement in throttle response. Being only a street driven car, I'm not concerned so much with numbers. How it feels to me in everyday normal driving is what matters to me. The headers did increase the sound a little more.
It will be interesting to see how it does at the next Mass. inspection. They use db meters now. I'm already thinking about some sort of baffling I can easily install/remove from the muffler tips. I remember years ago, my brother packing his tail pipes on his '56 Chevy with steel wool. The car had really loud glass packs. The steel wool quieted it down enough to not be a problem.
Always a cat and mouse game..........
I have over 3000 miles on mine with no CEL so far...with no tune or spacers. This is one of the claims Topgear makes..passes UK MOT inspection....
The following is taken from Topgears site for their 200 cell 996/997 cats...
This pair of high quality, 200 Cell Sports cats are sure to add power and a sportier sound to your 911 996 or 997 Carrera. This part fits all 996 Carrera and 997 Carrera Generation 1 (not facelift/PDK model) and can be a direct replacement for OE cats. The cats will add +12-+15 BHP and are compatible with aftermarket parts that fit OE, such as Topgear silencers or manifolds. The cats will pass MOT, won't trigger CEL and are a fantastic, easy fit.
I have Fabspeed Headers and 200 Cell Long-Pipes, they both have Cracked a few times and I have had to have them Welded
So I'm thinking of getting a new set of Headers & X-Pipe from Top Gear as long as the headers are MADE IN UK and NOT ASIA
My Question is though since I'm doing a LN 4,0L should I stick with the 54mm or get the 63mm X-Pipe?
and if do the 63mm X-Pipe should I stick with the 200CEL or get the 100CEL?
Wow. Their website here
https://www.topgear-usa.net/about-tg-usa
says this...
"With our combined decades of experience, exhaust components tested to perfection and a 300+ strong network of fabricators we leverage our industry leading guarantee and expertise to create the finest stainless steel exhausts all over the USA. The components are hand-crafted and welded in the UK and distributed via master franchises in the USA."
Either way, I'm very satisfied with the quality of the pieces I received where ever they originated. We'll see if they will stand the test of time.
I'd imagine cars with these which are tracked and see extreme temperatures may experience failures sooner and/or more often.
My other hobby is VW Vanagons using Subaru engines. Many of the custom exhausts made for these use stainless steel. We've seen header welds which have cracked. It appears to happen to the ones driven in the cold winter weather. Maybe the sudden splash of cold water onto a hot pipe could be the cause?
I don't know where you heard that, but I have been to their factory in Bridport and can confirm they make all their own stuff. Either that or the large lorries that I saw delivering steel tube all day are going to the wrong place!
Thank you for sharing! My headers on the C4s base plate and bolts are rusted. Also looking for an x-pipe to complement my PSE system. The Headers + x-pipe comes in half the price of the fabspeed. Looking to add about 30-40 HP with bolt on parts. Headers, x-pipe with 200 cell cats, an intake system, IPD plenum and that should get me 30-40HP.
