I was just wondering if anyone had any overheating problems with their stock cat. I was having overheating problems and replaced my main cat w/ a straight pipe, + i wired up my fans to come on w/ a switch. I havent had a problem since! Just wondering if anyone has had their car overheat w/ the stock main cat! I can drive the hell out of it in this west tx weather and it dont get hot as long as my fans are running, but as soon as i turn them off, my coolant starts to gurgle a little bit. my radiator has been relpaced w/ a fliudyne, and so has my precat.

 

The stock cat will get damn hot if you're sitting in traffic or driving it hard. I've had mine get pretty hot... but I've been running straight pipe almost right after I got my car. I've heard of the main cat causing problems... but like I said, I got rid of mine pretty quick

 

out of curiosity, how did this impact your boost/tuning?

Most of the stuff I read says that after a midpipe install it is suicidal not to have some sort of tuning, I am going to be owning an FD pretty soon, so just out of curiosity

 

Well I have 4" down to the catback, which is 3" - my boost comes in a bit later... smaller exhaust = less room to fill when building exhaust = faster spooling. I get full boost around 4800-5300RPM on my*T78. When I had the twins it was 3" all the way back, I just had my wastegate modified to prevent boost creep which is common on the stock twins with a straight pipe setup. Usually best to have some kind of restriction when running the twin setup... I am not too worried about emissions so I run straight.

Tuning is always an issue with exhaust mods, you can do a full exhaust on a base map, but tuning is always preferred, when you get into heavy mods you need a proper tune (i.e. Fuel, Ignition, Airflow, etc)

 

I don't think having a bigger diameter exhaust is going to make your car spool slower. The exhaust doesn't have to fill up for your turbo to spool lol. Any way it may feel like you are getting boost later but in fact it should spool faster and your power curve will indicate more power up top and some loss down low.

And yes I think a clogged cat would cause the car to run hotter coolant and also oil temps.

 

Thats what i thought, i guess it didint help that i dropped it(cat) while trying to put it back on...oh well iguess i ll just gut it all the way so when i get my car inspected next time,and have to put it back,it will at least look like i have a cat. There not very strict here anyway...... :-)