Hi fellas,

I'm considering installing a cup pipe and want to know how tricky it is to DIY. I can't find a guide on how to do it - has anyone seen one, or did anyone take any pics when they did their install?

Secondly, with no cat or silencers at all, would the lack of backpressure affect engine power much?

 

The cup pipe is very easy. There is not much to it. Take off primary muffler and attach cup pipe. I have my cup pipe off right now as I am in the processes of changing out the gasket on my left hand timing chain cover.

Cannot say much about backpressure, however with all silencers off and no cat, we may be able to hear you from this side of the pond. Most people cannot handle it with out at least one muffler.

 

I agree it is easy to install the cup pipe, but mine was not quite a "bolt-up". The support brackets for the original muffler will not fit the bare pipe. The new brackets that came with mine did not quite fit the hangers at the rear of the engine. I hated to do it, but a slight bend was required - not enough that it could not be bent back to re-install the stock muffler. It was tempting to go without supports for the light-weight pipe, but if you look at the secondary muffler, half of its considerable weight is held by the primary muffler.

I am still running the cat and the secondary muffler. The sound is not objectionable. I think I gained a few horsepower, but it might be just the noise making me think that.

 

Cup pipe is an easy install. there seem to be two kinds of mounting - the genuine Porsche cup pipe just uses two of the primary muffler mounting bracket bolts (the pipe has brackets on it which you just bolt through), whereas aftermarket pipes tend to use straps similar to the way the primary is mounted. You should be able to swap the exhausts in less than an hour - I change mine regularly depending on noise limits for the next track day. PS make sure you hang on to the primary mounting straps - they're about 40 quid each from Porsche!

A straight through system will be VERY loud - 115db or more. Don't know whether the lack of back pressure will be a problem, the Cup cars are set up to run like this (but with a cat).

 

Many thanks for the responses gents. Less than an hour is just what i wanted to hear!
I wonder if there's an aftermarket one with brackets on it like the original one.
Duck & Springer - which brand of pipe did you guys go for?

Its not going to be a permanent fixture, i just want to experience it at least once and while i'm at it, i might take it along to a car meet in London famous for some very loud TVRs


ps. I'll make sure i film the car with the straight through setup, and post it up here!

 

I bought mine off ebay. They are on there quite often. I think it was a Max Speed version(no affiliation). Fit is very good and it comes with straps.

 

Annoyingly there's nothing on ebay at the moment.

Does this one look like it might bolt straight into the existing holes,
rather than having to use straps and bend the mounts?
(Its a Dansk one from eurocarparts.com - £160)

 

There are no holes - If you look at the pic there are 2 straps that hold the pipe in place - these are shorter than the originals for the muffer - just unbolt the existing straps, pull the muffler out and fit the pipe in its place - use the shorter straps to replace the long ones - the tangs that you see on the pipe are used as set offs to hold it out from the engine and also for strap alignment - ? your not going to run the secondary muffler ??- just a "J" pipe? It will be loud, LOUD, LOUDER THAN LOUD,

 

Ah i see, thanks for that.

Heh heh heh! Thats the plan. Hopefully it'll spit flames too!
Just to be clear, its going to be taken off again after the planned outing. But i'll keep it in a box for 'special occasions'

 

Some of the cup pipes are split in the center and have a slip fit coupling and clamp, this makes it easier to install. My Dansk came that way.

As for the straps, those need to be bent the first time, but after that, swapping back and forth is easy. The hardest part of the whole job is dealing with rusted hardware for the cat shields and the lower engine belly pan if your car is so equipped. Really, after the first install, swapping back and forth is easy, but I will say that if you are doing this in your garage and you do not have a hardware store within a few blocks, please go buy a bag of hardware first and please budget 2 or 3 hours worst case.

Save yourself a lot of hassle and purchase some nice combination wrenches with swiveling ratchet heads in the sizes 10mm through 14 mm. Those will save a lot of time!!! Also, crawl under the car the night before and soak all the hardware down with penetrating oil.

FYI, I installed a CAT bypass first, and then the cup pipe. I ended up re-installing the primary muffler because the resulting sound was too loud and annoying to me, and most likely illegal here in the USA and my guess it would be for you in the UK as well. I may reinstall mine if I participate in a DE weekend.

 

Doug thanks, great info. I hopefully have enough hardware to get the job done (touch wood) if not i have friends nearby that should have what i need. Although this could be a good excuse to buy some swiveling ratchet heads.

Thanks all, i'll let you know how i get on

 

Got the pipe installed in minutes, it came with 2 jubilee's which i bolted around the existing mounts.
As for the loudness...WOW...its VERY loud. Far too loud for everyday stuff. But it does sound great.

Even though its rather offensive on the decibel scale, i'd challenge ANY 964 owner to hear it and not grin

 

I guess you'll end up like a lot of us with an exhaust system in a kit of parts to suit whatever track day you're doing. My RS has a Cargraphic MAF conversion with BMC air filter. With a cat bypass, both silencers and the MHP silenced exhaust tip, it will give 99 dBA @ 2/3 max revs, measured at 45 degrees from 500mm.

With cat bypass, cup pipe and normal exhaust tip it goes 107 dBA or 105 dBA with the silenced tip. So, my normal road set up will not get me on 105 dBA track days but the silenced tip will. In my version of full stealth mode, I can get on most track days.

 

Greg,
Sorry if this is a bit late for you, but here is a good primer on installing the C2/C4 bypass pipe w/photos from Pelican Parts. I am considering doing the mod myself.

http://www.pelicanparts.com/techarti...ler_bypass.htm

ketel

 

Hi, I also fitted a cup pipe and can confirm it is a 1 hour job max. Got mine from Porsche Shop

I also fitted a G pipe at a later date but it was a complete disaster (fully straight through system

Firstly it was unbelievably loud but most of all the car lost all of its low down torque. There was virtually no back pressure and the car lost it low range uummppp!

I chnaged straight back mainly due to the difference in performance

Cheers

Simon