Catalytic converter and heat shields

[DoubleV]

I have a 78 Cutlass with a stock pellet style converter. Im gonna replace it with a less restrictive more modern style cat.

So I noticed the 78 does not have a heat shield bolted to the floorboard like on my 85. Can't use the heat shield from the 85 on the 78 cuz the 78 doesn't have the mounting tabs on the floorboard.

I read somewhere ( could be total BS of course ) the older pellet style converters gave off less heat than the newer kind, which is why the older cars didn't have a heat shield and the newer cars did/do.

So is running no heat shield with a new cat gonna really matter? Anyone ever have any issues with this before?

 

[DRIVEN]

Many aftermarket cats have heat shields built in to at least one side.

 

[Clone TIE Pilot]

You will want a heat shield.

 

[TURNA]

Do u need a cat to pass inspection? If not just get rid of it.

 

[pagrunt]

If no sniffer test just hollow one out & call it a day.

 

[DoubleV]

Thanks guys but I'm not asking for advice on whether or not I should keep a cat on my car or not. I fully understand the pros and cons of deleting it. What I want to know is if anyone has ever ran into issues running a newer style cat on a car with no heat shield.

 

[DRIVEN]

I didn't for 5 years. Mine had an integrated shield. Now I live in a free state and have no cat.

 

[565bbchevy]

Typically the converter sits under or near a foot well area so I would run a heat shield regardless even if you have to fab one out of aluminum.

 

[DoubleV]

Typically the converter sits under or near a foot well area so I would run a heat shield regardless even if you have to fab one out of aluminum.

So is it your belief that a newer style cat would cause more of a heating issue over the old style cat?

Keep in mind of course that the 78's ( and some other years I suppose ) didn't come with a heat shield, so was this an oversight on GM's part or did the older style converters simply have less heat issues than the newer ones?

P.S. I know most newer cats have built in heat shields but don't know how well they work over a dedicated later model factory shield.

 

[565bbchevy]

So is it your belief that a newer style cat would cause more of a heating issue over the old style cat?

My belief is anything that slows exhaust flow even a little is going to be hotter than a straight pipe in the same location and I personally have never owned a vehicle that came with a converter that didn't also have a heat shield.
Besides I would rather fabricate a heat shield and install it rather than find out I need one after putting my exhaust on.