Jump to content
SAU Community

Recommended Posts

hey mate, i have done it on a N/a 4cyl , i wouldnt recommend it for a n/a car and i wouldnt do it on my r33.

i doubt there is much performance ot be had with a street r33 any ways ?? is there?? it would be very minimal if u had a dump full zorst and a high flow cat alrady.

Link to comment
https://www.sau.com.au/forums/topic/134803-cat-punching/#findComment-2505374
Share on other sites

Hey guys,

I am aware of punching the center out of a cat is illegal . Im thinking of punching out the inards of my sports cat and replacing it with a 3 inch pipe.

Anybody got any ideas and comments on the matter?

not sure what info your after. you admit you know that its illegal, thats really all there is to it

theres very limited gains to be had

i had one on my 33 T when i first got it

replaced it and felt or saw no difference on the dyno

a very slight deeper note to the exhaust and a little more stinky thats the only differecne between that and a god quality hi flo item

Jimbo

Link to comment
https://www.sau.com.au/forums/topic/134803-cat-punching/#findComment-2505383
Share on other sites

if you are in qld you will just have to watch out for the hoon squad. when they are doing a blitz they have a epa station setup and they will tell you to go straight to it and escort you there. they did 1 up here in gympie. had it setup for emisions and noise. went right over the car.

Link to comment
https://www.sau.com.au/forums/topic/134803-cat-punching/#findComment-2505525
Share on other sites

lol i saw "cat punching" and the last post by ctjet, it made me think of something entirely different.

I think the noise must depend on the car. A couple of my mates have had theres hollowed out and it sounds sh!t.

Personally I would just get a high-flow.

Edited by shyster
Link to comment
https://www.sau.com.au/forums/topic/134803-cat-punching/#findComment-2505533
Share on other sites

When my old S13 was brought into the country, the CAT had been split at the top - gutted out - exhaust went straight through - and finally the cat sat back around the exhaust and welded at the top where no one could see.

Sensor was still sitting in it - though it was ummm loose and rattled..lol

Went to replace it but when I took it over the pits at the RTA for first rego they didnt even test it!

Link to comment
https://www.sau.com.au/forums/topic/134803-cat-punching/#findComment-2505971
Share on other sites

The RSPCA will be onto you pretty quick for punching your cat.

PS think about what it does to the environment, and whether you are that selfish to do it for the maybe 5kW extra. Just go buy a good new metal substrate cat.

Link to comment
https://www.sau.com.au/forums/topic/134803-cat-punching/#findComment-2506028
Share on other sites

Hey guys,

I am aware of punching the center out of a cat is illegal.

Anybody got any ideas and comments on the matter?

Yeah, I do believe that punching the innards of a cat is illegal. But I don't know, I much prefer punching cats in the face.

Link to comment
https://www.sau.com.au/forums/topic/134803-cat-punching/#findComment-2506572
Share on other sites

knocking the car isnt the bet idea

best to get a pipe.

have a look at it all, the exhaust gas would be mising around something shocking, so possible gain... but a better gain from a straight pipe thats evenly flowing

Link to comment
https://www.sau.com.au/forums/topic/134803-cat-punching/#findComment-2507422
Share on other sites

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

    • A 1.5 way is a 2 way. It is just a 2 way with a less aggressive ramp on overrun.
    • The ABS and/or TCS being missing/broken will not cause the engine to misbehave. It just casues CEL to come on and annoy you. The CEL is useless if it is always on, so you have to do the things you have to do to get rid of it, so it can be useful. Being a Stag ECU, then yes, it will not expect TCS to be present. But it will expect ABS to be present and working. You will need to either make the ABS CU talk to the ECU (don't ask me what that will take on an NA R34), and make sure the hardware is working....or, you just need to blank it out in Nistune. Do not persist with the stock ECU. You will just have problems. Gte it Nistuned. Start from there. DO YOU HAVE A BOOST SENSOR? The ECU's boost sensor that it. It is connected to the loom at the rear of the coil cover. Usually rides on the firewall on an R34, but is usually bolted down to a bracket along with all the other crap at the back of the coil cover when a Neo is dropped into another car. If you do not have it, the ECU will shit the bed. So, do you have one?
    • So sadly the fuel pump etc was not it. The pump and filter is new and it is still cutting around 4000 rpm. A read something about ABS/TCS (engine is from stagea and ECU too so no TCS) and i dont know for 100% that my car has ABS. It has ABS "cube" in engine bay but i dont think it works(or at least from my braking experience). Can be something like that?  I will be driving the car next week to Nistune tuner to properly see what is wrong...  
    • the Tomei LSD fluid with lsd kit. frustrated that it was shaking the car to crap and affecting everything else negatively, I pulled the diff last night, and removed the lsd carrier, could not find anything wrong, however it seem to be 100 locked up acceleration, and deacceleration, wondering if they sent me a 2 way not a 1.5??  either way I installed the stock open carrier back in place. test drove everything smooth as butter again. no shake, shutter, random, what felt like clutch slip and grab or drive shaft play, etc. something differently wrong in side the lsd. I might bother taking it apart (if possible) to figure out what's going on inside this carrier, as bought too long ago to return.  only draw back is its back to a one wheel wonder.
×
×
  • Create New...