Discussion
Is this pretty simple? Trying to do it by spending as little as possible, in keeping with the ethos of the whole car. It appears to have a stainless cat back fitted to it, but the cat is really rattly and as the exhaust is a bit muted at the moment I'm hoping removal of said cat would rasp it up a bit. Can I just remove the cat and then get a piece of straight pipe fitted? How hard would this be? I'm not keen on buying a proper de-cat pipe because circa £50 for a straight bit of pipe seems a bit excessive to me....
Any musings, help etc much appreciated
Ollie
Any musings, help etc much appreciated
Ollie
It's important that it's the right length and has the correct flanges welded on at either end in the correct orientation - so getting one made up by someone might not be any cheaper than buying one off the shelf. Cheaply-made ones occasionally pop up on eBay.
The alternative is to whip the cat off and see how much of the insides you can mash up and extract with a pointy stick
The alternative is to whip the cat off and see how much of the insides you can mash up and extract with a pointy stick
I bought a hardly used stainless steel de-cat pipe off ebay for £15...so there are bargains out there. Removing the old cat was a right f
king pain in the ass, needed a day of soaking with WD40 before I could remove the four bolts holding it on. After that it was a piece of piss to fit and has totally transformed the car!!!!! Pulls so much cleaner from low down than it did before and the noise is STUNNING.......
king pain in the ass, needed a day of soaking with WD40 before I could remove the four bolts holding it on. After that it was a piece of piss to fit and has totally transformed the car!!!!! Pulls so much cleaner from low down than it did before and the noise is STUNNING.......You haven't specified mk1 or 2, but presuming you have a mk1 it's this part: http://www.mx5parts.co.uk/product_info.php/product...
to make sure you get the right length, just measure the length you need.
I fitted a non-silenced de-cat to a full stainless system and it was very, very loud. I think if you got down the "piece of steel tube route" you'll find it over loud, and hard to fit. Why not just get the right size, complete with gaskets? I don't think £50 is that much considering a new cat is £150.
to make sure you get the right length, just measure the length you need.
I fitted a non-silenced de-cat to a full stainless system and it was very, very loud. I think if you got down the "piece of steel tube route" you'll find it over loud, and hard to fit. Why not just get the right size, complete with gaskets? I don't think £50 is that much considering a new cat is £150.
I was planning on just removing the shagged old cat (Disc cutter?) and perhaps sleeving a tube over the gap with some clamps and exhaust paste. Perhaps this is a bad idea. Just resent paying £50 for a decat pipe when you can get a similar bit of straight pipe off another exhaust for £0. I would beat the old cats insides out but not sure if this would be that effective, plus the actual casing is really rattly.
O/T here, but just so chuffed with the car at the moment, just completed Le Mans and back without missing a beat, all stickered up. Even coaxed a couple of weedy burnouts out of her! This much motoring fun for well under a Rio can't be wrong!!!!!
O/T here, but just so chuffed with the car at the moment, just completed Le Mans and back without missing a beat, all stickered up. Even coaxed a couple of weedy burnouts out of her! This much motoring fun for well under a Rio can't be wrong!!!!!
Just remove it and gut it. I did this using a long screwdriver and a broom-handle after my stock cat got clogged.
I have a Larini Sport cat fitted at the moment but use the gutted cat when I know I'll be over-fuelling (e.g. before tuning after fitting bigger injectors).
I have a Larini Sport cat fitted at the moment but use the gutted cat when I know I'll be over-fuelling (e.g. before tuning after fitting bigger injectors).
Edited by MX-5 Lazza on Wednesday 18th June 12:12
OllieBirmingham said:
I was planning on just removing the shagged old cat (Disc cutter?) and perhaps sleeving a tube over the gap with some clamps and exhaust paste. Perhaps this is a bad idea.
You could do that, but you'd have to chop the flanges off the downpipe and exhaust to do so. Sleeved joints are much more of a pain in the arse to get fitted and aligned properly. There's nothing worse than spending an hour under the car beating the pipes together with a hammer, only to find out that you've rotated the exhaust by five degrees and it now knocks against the sides of the transmission tunnel over every bump. (flashbacks from mini ownership )MX-5 Lazza said:
Just remove it and gut it. I did this using a long screwdriver and a broom-handle after my stock cat got clogged.
I have a Larini Sport cat fitted at the moment but use the gutted cat when I know I'll be over-fuelling (e.g. before tuning after fitting bigger injectors).
I'm pretty sure the external casing is rattling so removing its innards would probably not help with this. Plus, I'm sure a straight bit of pipe would always flow better than a cat with loads of detritus left in it. I was just thinking about taking it up to a friendly exhaust place and chucking them £20 or so to sort something out.I have a Larini Sport cat fitted at the moment but use the gutted cat when I know I'll be over-fuelling (e.g. before tuning after fitting bigger injectors).
Edited by MX-5 Lazza on Wednesday 18th June 12:12
The cat itself is only thin steel with a heat-shield over it.
If it's just the heat-shield rattling then a jubilee-clip or 2 will fix it.
If you gut the cat there won't be any detritus left in it. They use a ceramic honeycomb which can be totally removed with a bit of brute-force & ignorance (I have a bit of the first and a lot of the last).
If it's just the heat-shield rattling then a jubilee-clip or 2 will fix it.
If you gut the cat there won't be any detritus left in it. They use a ceramic honeycomb which can be totally removed with a bit of brute-force & ignorance (I have a bit of the first and a lot of the last).
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