Mark J

Am thinking of getting this soon to compliment the cup bypass pipe already installed.
I can see two available made by Dansk and another by DesignTek. Any comments positive or negative about either ? ie good fit, problems with either etc ? The Dansk is about £45 dearer.
Do you need a new lambda sensor or can you just unscrew old one and fit to new bypass ?

Would i be better off paying to have it fitted or can it be done in your average home garage with a trolley jack and axle stands ? Or is it a Pita to match it up to existing system ?
I know Design 911 have a fitting shop not too far from me so depending on what they charge for an hours fitting, could be a viable option instead of leaving my knuckles peeled like a banana.

Andy Roe

I've the Danske one fitted (also from Design911 and fitted by HP Motorsports which are next door to them). It's a good idea to fit a new lambda sensor too as it can be difficult to remove the old one without damaging it (you normally need to use a blow torch!).

mr pg

I recently fitted a Hayward & Scott on mine. This doesn't have the brackets to retain the existing tinware.
Biggest problem is removing the very corroded nuts. Spray liberally for a few days before with WD40 (or similar). Even with this, 3 of the 5 nuts would not budge, and I had to revert to using a Dremmel with a flexi extension and small grinding disc to cut through the bolts. Replace all the bolts with new ones (I got some from work, and the rest from a DIY store. All stainless steel.). I also replaced the sensor, which is easier than I had been led to believe. You don't need to remove the rear blower to access the connector. Just remove the down pipe from the blower to get to the connector which I managed to do with one hand.
Did mine with a trolley jack and axle stands as a precaution. Took 3-4 hours due to the rusted nuts and bolts.

Mark J

Thanks for replies so far gents.

Andy, how much did HP charge you for fitting the CAT bypass?

I did the cup bypass myself but i had access to a proper car lift then. Mr PGs experience sounds like my own on previous exhaust mods when it comes to seized rusty nuts !

Andy Roe

I can't remember exactly as it was done at the same time they were servicing the car, but I can't imagine it'd be more than an hours labour.

Mark J

just got quoted two hours labour at £65 an hour to fit a cat bypass !!...£376+VAT (£432inc) for one piece of an exhaust system !....err, no ta

Crazy price, nothing like being fleeced eh

John Boggiano

What?!! Wow.

Edit: Just looked nack through my records - my car was fitted with one by Tognola while it was out of my possession temporarily - the invoice lists the part only at £271 plus VAT.

Seems a hell of a lot for what it is.

Pesty

Mark, I iftted my own

I don't remember issues with bolts as my mech always removes the exhaust on servicing and replaces them every year anyway.

4 bolts one end and a clamp at the other. I didnt fit the heat shields( they had fallen off the original cat anyway) would not be a bog job just get some new bolts and possibly cage nuts.

I did buy a new oxygen sensor at around £79.

there are special sockets for removing oxygen sensors in order to accomodate the wiring. they don't cost that much. Might be worth while trying to remove it first.

2 hours ?? who was that please ?


take wheel off, undo oxygen sensor connector, undo 5 bolts, fit bypass up refit bolts, re connect oxy sensor.
took me half an hour. even with problems it would never take the most ham fisted of mechanics 2 hours

hardest bit fir me was re conecting teh oxygen sensor found it a bit fiddly

964russ

I paid £40 for a simple by-pass tube, £55 for a new sensor and £35 (1 hour) labour.
The prices youve looked at are way to much for me, do you want a silencer or just a de-cat? You can get a de-cat silencer or a de-cat pipe.
If the sensor unscrews you dont need a new one, and the bolts are allways seized solid, you just cut them off (new bolts are pennys). You may allso need anew exhaust strap, but there not expensive either.

mr pg

Have to agree with Pesty. If your bolts are in good nick, it won't take long at all. On mine even having cut through them I still had to knock the bolts out as they had correded in the joint holes as well as the nuts being seized.

Pesty

Yeah as russ says even if teh bolts won't undo cut them off. Nut spliters are great

1 hour labour is probably right and not bad to save yourself agro but not two hours I think thats taking the P... where are you in the country?

bobster964

Presumably everyone who's fitted a bypass is happy with the results?

I'd be interested to hear what it's like in combination with a cup pipe.

It it much noisier? And more importantly any performance gain noticed?

Do tell as it's probably the next job on the list!

Thanks,
Bob.

mr pg

It makes a slightly deeper rumbling sound compared to stock. Difficult to say if any performance improvements, but most claim to add anywhere between 10-15bhp depending on engine condition, etc.
There was someone (low964, red with black wheels, organises Le Mans trips) at the recent CG meet with cat and cup bypass. Have heard his car before, and you can definitely hear it coming!

biggles

I will be tackling mine as well as the G Pipe in a couple of days, did it a number of times on my 951 so assume it cannot be too hard. Not sure if this will work on these nuts, but I was told to use brake fluid to help with tough nuts. Seemed to help when replacing my fuel filter, after a few days of no luck.

Good luck

biggles

Mark J

I agree with most here, 2 hours labour at £65+vat an hour is a p-take, considering they have a fully equipped service bay ! I bet they could do it in half an hour on a car lift.

The shop was Design911. I live in North Kent (brands Hatch) and they have a fitting shop nearby so was hoping to nip up this week and get it fitted before i return to work next week. However that quote, not much shy of £450 all in, has left me cold. Crazy money considering its only a flipping CAT bypass !

Just not sure i could get the old one off and new one on in my limited space and not too fond of yanking on some rusty old bolts with the car on axle stands.