Do I have to leave the catalytic converter heat shield on? Are there any draw backs to not having it on there besides catching tall grass on fire?

The reason i ask is because mine is broke and rattles, and all attempts to stop it have failed, so i am going to remove it. Also, I have a leak at the Y-pipe and I plan to weld it, and would like to just leave the shield off.

Thanks.

 

The heat shield is there for a reason.

 

is it on the very bottom? should be ok to pull off.
aftermarket cat swaps dont typically have em either (usually built in

 

I KNOW the heat shield is there for a reason. I am sure mazda didn't just waste money putting one there. I want to know what that reason is specifically so I can decide on how to solve my problem. I specifically asked what the draw back of removing it was, and if you knew what would happen by removing it, then I would assume you would know WHY it was there. Your snide remark and lack of post depth tells me two things. First of all, you are either two lazy or don't know what you are talking about, or second, you found this a great opportunity to raise your post count.

Anyway...

I have seen several pics of heat shieldless exhaust setups, but I don't want to ruin my cat, so any help would be appreciated.

 

You didn't say, but if you have the stock cat, I'd figure out how to reattach it. The heat coming off the cat and the front half of the exhaust is pretty substantial. I'd imagine that with a functioning cat, and a heat shield removed, at best the passenger side floor would be uncomfortably hot, at worse could melt the tar insulation or God forbid, start a fire.

Now if you had a test fight or gutted cat... I'd consider removing it.

 

Good, I think you answered your question.

Lets see, its called a heatshield so it must help in preventing heat going through it or something like that. I think thats the reason its there!

Its there to prevent heat, if you want an example my buddy removed his and his carpet got all gummy after driving it around a bit. Fun stuff.


Probably option #2, I want to have a bigger e-penor. And by the way, the fan shroud is there for a reason too...it helps move air. Oh, and so is the motor, it helps move the car.

Which makes none of them done correctly unless they really really really need to save that weight. It won't hurt your cat, its the cats heat its preventing from spreading. But taking it off doesn't make it right.

 

Why don't you just buy a new, hi-flow, cat?

 

You inadvertantly answered my question in the form of a snide remark, thanks! It is the lower heat shield, so I shouldn't have any melted carpet. You could have said "removing it will melt your carpet" and I could have given you further information to the fact that I am speaking of the lower heat shield. But you chose not to and just spouted vitriol. I digress...

If you would like to know, I was curious if removing the lower heat shield would create stress on the lower portions due to the lack of insulation. For example, fracturing of the substrate from the bottom being cooler than the top portion. So what it sounds like to me, removing the lower heatshield would have no effect.

I don't want to replace the cat because it still works. I have quite a bit more to replace on the car that is more important, I would just like the rattling to go away if I can help it.

Thanks to the folks who have given helpful feedback.

 

Mine had the same problem. It would rattle until I couldn't stand it. It got soo loose that it was dangling and scrapping the road! So, I twisted it off, like I just kept twisting the piece around until it came off(just to clarify). I don't have any metallic noises, but I guess a problem is that I can feel heat coming out of my shifter hole area. It could be me because I've learned manual drive a month ago, but you have to be there to understand what I mean. Its not "burn hand hot", its "should I feel heat here" hot.

 

Hehe, my shifter boot is busted so it couldn't be any worse than it already is. I don't even need to run the heater when it is cold outside.

The rear of the cat shield (part toward rear of car) broke. The metal is there and so are the bolts that hold it but the metal broke off. So where the bolts would normally thread through on the shield is actually busted off of the shield. The front portion is fine.

I'll try to weld the shield back together I suppose but if that doesn't work, then it is coming off. If my carpet melts from the lower sheild being removed or if my cats substrate busts, then I'll post up.