Jump to content
SAU Community

Recommended Posts

I am getting my cat checked out because I suspect a blocked cat, buti don't have the money this week to pay for it! He said he would just gut it for me if need be!

Can some one tell if it's been gutted from looking at it?

Thanks

  • Replies 70
  • Created
  • Last Reply

Top Posters In This Topic

Not without physically taking it out and looking down it, You should be pretty sweet for any checks the police do on it.

Rubbish.

If you simply tap it with a torch or similar you can EASILY tell that it is hollow.

What about sound wise? My exhaust smells anyway, my car a few months ago was running super super rich( now is fixed) and dr drift told me that it would have stuffed it, but he also said it wasn't block. So I haven't changed it yet but the last 3 weeks I have been running 10psi all the time and maybe the extra heat or gases have made it block up! So I'm getting is checked

you can tell a difference per car, but its hard unless you hear before/after.

Either way mate it's illegal, and easy to work out.

You run the risk.

Fair call, I will just wait and see what he finds, maybe it's a boost leak he is changen my cooler to so he will check everything

Some police use a infra-red thermometer to measure temp before & after the cat. Can't thionk which way it is right now (just woke up) but I think with a cat in place it is hotter. Have had it done to me but luckily I run a cat. MASSIVE fines if you're caught without one...

Fairly sure something with my cat has gone to shit, as there is often a strong fuel smell when getting back into the car after it's been sitting for about 30 - 60 mins after running. That, and it used to make a rattle/vibration noise which shut up after a while, so it probably came out the exhaust rofl

But yes, you will be able to smell it.

Some police use a infra-red thermometer to measure temp before & after the cat. Can't thionk which way it is right now (just woke up) but I think with a cat in place it is hotter. Have had it done to me but luckily I run a cat. MASSIVE fines if you're caught without one...

True, the cat works by re-burning exhaust gases (least technical way of explaining it), so the oulet on the cat will be 40-60ish (I think?) degrees hotter than the inlet, provided it's working correctly.

Rubbish.

If you simply tap it with a torch or similar you can EASILY tell that it is hollow.

Wow, I wasnt aware of that, My appologies... The thought never really crossed my mind, Things are way more relaxed here in New Zealand, I dont even run a cat in mine. The police here in Hastings are more interested in people who are drink driving or actually making the roads more dangerous for people to drive on.

Some police use a infra-red thermometer to measure temp before & after the cat. Can't thionk which way it is right now (just woke up) but I think with a cat in place it is hotter. Have had it done to me but luckily I run a cat. MASSIVE fines if you're caught without one...

that's bullshit... they would have to prove calibration of the thermometer and also correct use.

also infra red thermometers only measure surface temperature, which can be altered by differing materials (which are legal)

it's a takethatbulshittocourtandwin scenario

that's bullshit... they would have to prove calibration of the thermometer and also correct use.

also infra red thermometers only measure surface temperature, which can be altered by differing materials (which are legal)

it's a takethatbulshittocourtandwin scenario

Just as they'd have to prove their good judgement and/or qualifications when defecting you for engine/vehicle modifications?

They don't need to prove anything, they just need to form a hunch that something's wrong, and off you go to a place where people WILL know.

Easy just make it so low they cant get under the car to tap the cat to see if it sounds hollow :D

+1 for being able to smell it to, and if your car's white, be prepared for a fuel stain that wont come off.

I know several transport inspectors and engineers who can tell if your cat has been gutted just by the sound. It is

different. The average cop probably won't be able to pick it but some can pretty accurately too.

Plus the aforementioned smell and the hollow noise if you tap it.

much more raspy deeper sound. theres many for sale on ebay advertised as hi flow. their called test cats.

theres power gains but you will have a 5 grand fine if you get caught.

it will mess with ur ecu fuel system and o2 sensors.

excessive soot.

It's actually a 10k fine.

& Hamish, they then send you to EPA who verify you have no cat or internals...

& basicallty it doesn't matter if their thermometer reads 50 degrees out, they are only looking for a difference before & after cat.

& different materials may make a slight difference but not much, & anyway almost all of us run a s/s exhaUst & cat which they can tell by looking

Edited by wlspn

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Hi from Canada, Both of my calipers are starting to fail. My car is a 2005 M35 Stagea ARX and I can't seem to find any parts or any cross reference caliper that would fit my car. Is there a company or a similar caliper that would fit and I could replace the OEM one. Or if anyone knows where I can find a new OEM. Any help is very appreciated. Let me know!
    • Maf is a question mark but TPS  I have set at 0.47, the fact that I’m getting proper voltage range out of it with the key on leads me to believe it’s functioning properly. I’m getting proper voltages on basically everything. I still need to look up voltage ranges for z32 maf and test that 
    • Honestly no not at all, but it’s a very basic tune, it’s stock injectors q45 tps and z32 maf. Other than that it’s a completely stock base map. The file is from nistune and from my understanding if it was tune related I would be able to unplug maf and tps and it would still start even if it was a really shitty start. I have tried starting it with coolant temp, maf, and tps unplugged none of those 3 togethor or individually changes anything 
    • 🏆 Skyline Supremacy Meets Mount Panorama Magic 🏆 Join SAU NSW as we take the long way to Bathurst, the home of GTR greatness. Saturday 30th August 2025 7:00AM Meeting Hanna Park North Richmond 7:30AM Departure Cruise Via Bells of Line Road 9:00AM Arrival to Stop 1: Golden Poplars Meadow Flat 9:45AM Arrival to Final Destination: Mount Panorama Motor Racing Circuit Meet Location: Hanna Park North Richmond Stop 1: Golden Poplars Meadow Flat Final Destination: Mount Panorama Motor Racing Circuit   *Disclaimer* There will be a lead and follow car so no one should get lost. If you would like to attend or bring others along please put your name down and a +1 as numbers will be needed prior! This is NOT a race and we will all be adhering to all road rules. If this is what you want please come to one of our many track days. This is an official SAU:NSW event and will be run under a CAMS permit. One of the things that really sets our club apart is our commitment to being true enthusiasts. When on normal roads we strive to maintain good relations with the authorities as well as the public in general. When attending one of Skylines Australia NSW events please try to: • Be aware of surrounding environment and act accordingly. • Drive courteously on the state’s roads as a true enthusiast should. • Understand how important it is to maintain the good name of SAU NSW and thus, treat others accordingly. • Any misbehavior will not be tolerated and you will be asked to leave.
    • What does it look like with highway driving? And yes, I had a similar thought as Duncan. It looks quite similar in my Stagea and I have made myself accept it as normal. Might have to look into it some day   Highway gets as low as 10l/100km on my end so I'm not as worried about it being a mechanical issue. More likely just the tune on the haltech.
×
×
  • Create New...