Scoobyprincess90

Hi all looking to replace my CAT on my downpipe, looking at a few options, I can either get a Prodrive sports CAT and just get that installed in the original pipe or go for a Japspeed Sports CAT downpipe or similar. I’m just wondering what would give me the greatest chance of passing emissions. Any help appreciated xx

Vxr2010

prodrive is a better built cat , my japspeed one has passed its last three mots no issues , just needs to be hot first , it’s down to your budget , if you can stretch to a prodrive one then 👍😁

ade_sti

iTrader: (2)

I have a Prodrive cat on my STi, has passed the MOT in the Uk for many years and now I have the car in Spain also passes the test here. Just needs the car hot to ensure it passes without me worrying!!

jaygsi

iTrader: (46)

What year Impreza is this?

Also depends on the sports cat, as you can get 100 cell or 200 cell. I have a 100 cell and it's a pain to pass mots. Need it red hot. 200 cell sold pass alot easier.

Think Japspeed are all 200 cell now. Prodrive I think is either 400 or 500 cell.

If you get a Japspeed one, remember there all 3" bore and your standard system is 2.5" bore.

So won't be good for flow going from 3" to 2.5" bore. Would need full Japspeed system.

Vxr2010

i would get a 200 cell cat , less hassle mot time , my 3 inch japspeed just bolted up to my 2.5 inch system with no hassles , and the car runs well , it was the cheapest but apparently quite good cat to buy at the time 👍

jaygsi

iTrader: (46)

Really wouldn't bolt a 3" bore to a 2.5" can't be good. Scoobyprincess90@ needs all same bore.

JDM_Stig

iTrader: (3)

Why?
What are you trying to say?

Scoobyprincess90

Hi it’s a 2006 WRX if the Japspeed is a 3 inch I’m pretty sure there’s a bracket I can buy to hook the exhaust together to match my 2.5 inch.

When I search for Japspeed on the internet it comes up with a company call Gravity, are they a supplier of Japspeed exhaust? Or shall I go through the main webpage.

1509joe

iTrader: (2)

Most downpipes all had a taper down to 2.5" it was harder to get a full 3" downpipe than one with a taper too 2.5"

adam.pah

I think they're the same company. I got a whole load of stuff from Japspeed in the past as one of my mates is sponsored by them, I noticed that one of the induction kits they supplied was a gravity one.
I hade some alignment issues fitting the japspeed dp. Even when I paired it to their full system, it didn't fit well. In the end I decided to get a centre piece custom made as nothing fitted properly. I guess you get what you pay for.

I personally wouldn't use them again for that reason. I've never had any issues with Haywood & Scott personally. I have seen some pictures of poor workmanship but never experienced it myself. Ian has always been helpful and custom made me several things in the past at reasonable cost.

jaygsi

iTrader: (46)

I understand that many taper down to 2.5" but surely if it's a 3" down pipe matted to a 2.5" the lip caused surely, by the difference in size will effect the flow of the gases leaving the exhaust.

adam.pah

There's a special flange that you can use.

Gambit

iTrader: (6)

https://www.mishimoto.co.uk/subaru-e...k-exhaust.html

bunsofsteeeel

iTrader: (1)

Give Martin at infinity exhausts a call he will be able to help you

jaygsi

iTrader: (46)

Ah ok, that's looks a good enough option. Nearly as much as a Japspeed cat though

Scoobyprincess90

Just been looking at used Prodrive CATs on Ebay realistically would a PPP Cat that’s 10-15 years old still pass an emissions test?

jaygsi

iTrader: (46)

Never heard of one that didn't. Worst case you would need to run cat cleaner though it. Which is what I plan for my next mot but that's only because I have 100 cell cat.

Prodrive will pass with no issues.

Scoobyprincess90

Ok Thanks :-)

Scoobyprincess90

Are the 100 cell cats really that bad to get through an MOT?

i have heard it’s clench your Butt hole time when waiting for that MOT.

jaygsi

iTrader: (46)

Your analysis is bang on. My bum is clench everytime. And yes it is. Doesn't help that cars not used often.

Have to take on a long drive. Then last time I had to take it out again. Then mot guy had to rev 3000 rpm for about 3 mins, until the car starts hunting. Then it will pass.

Don't get one, there a pain in the bum. Going swap to 200 cell soon.

Henrik

iTrader: (5)

totally agree with jaygsi on this one - I hate emissions tests with my current setup - should have kept one of the many PPP cats I've had through the years

kav76

Another vote from me to stay away from 100 cell cat just from my own experience had a 100 cell cat tried everything to pass MOT with no luck got a 15 year old Prodrive Cat on eBay for £350 and passed first time, well worth the investment.
I have read on the forums that people have said they have passed MOTs without Cats attached at all. So it really is about on the day.

jaygsi

iTrader: (46)

Lol I think the passing an mot without cats is more of who you know, not what's on your exhaust

1509joe

iTrader: (2)

You Sir persist in claiming that these cars won't pass test without a cat. I would not like to think you are insinuating that my emission test results are false. If you would get your car mapped correctly and look after all the emission related sensors i.e. O2. MAF, injectors, plugs you may have a chance of passing.

Rusti

iTrader: (4)

Clearly some 'blind' testers out there as its pretty obvious on visual inspection whether the car has a cat or not. Emissions are the least of your worries.

1509joe

iTrader: (2)

If the vehicle passes emissions with flying colours they tend not to look. One time I was questioned and told them the second resonator which I had welded in was an aftermarket cat.

jaygsi

iTrader: (46)

Sorry I can't believe it, I'd like your telling me the Earth is flat

jaygsi

iTrader: (46)

I need the name of your mapper it seems ?

1509joe

iTrader: (2)

Just shows how much you know. The test sheets which are government run test stations are posted here somewhere if you look.

1509joe

iTrader: (2)

A couple of different dynos and mappers with three different cars. You can't even tell the truth who you are so I wouldn't be telling you anyway