yup posted same question in exhaust board...doubt they actually know the history of them but anyway:

from 82-92 where the cats the same size? Even the single cat cars to the dual cat cars (like mine) were the converters the same

did they always have air tubes? Where they always held in by 4 bolts?

Id really like to find this out as im looking to get a junk pair to hollow them out.

Thanks! Steve

 

alright lets make this easier...If you have a SINGLE cat car and you post a picture of ur cat. Just dont even bother jacking the car up a side shot will show me the size enough to know what im looking at.

So anyone out there gets a second could ya take a picture of ur cats for me.

thanks, steve

 

i would, but my whole underbody is covered in oil from a leaky oil pan

 

No. No. I think so. No.

They went to a slip on style in 1986, the older versions were 4 bolts. Get one off a TPI or HO car, if thats what you have now.

FYI most wrecking yards wont sell used cats, illegal to here and maybe everywhere... at least places that I have been.

 

i got a used cat from the junk yard for $25 this was in Mass. i know that there is a place that will pay you $15 for used junk cats that why you prob wont get it cheaper then 15, just some pointles info

 

well my car is a dual cat...and it has 4 bolts per cat...so i dunno about that 86 year thing.

I went to a junkyard today...all 3 thirdgens...gutted of all exhaust.

I guess i can ask in the classfied...i dunno what to do i dont wanna hollow out my catcos...cause i need them for emmisions and there just good high flow cats...i dont wanna buy expensive new ones either.

 

This may sound strange but, my old 88 formy 350 and my gta 350 both had single cats. Now I took them both off and was surprised to look in them and see only the air tube in them. There wasn't any material to "gut" out. I always thought there was some sort of matting or something in them.

Later,
Conrad

 

Oh I missed that. The dual cat cars are kind of unique. If you are looking for something easy to swap in/out you may need to have something fabbed up. The front side doesnt have a connector besides to the manifolds and the rear side is different (location of connection and style of connection) than the single pipe setups.

 

1982-92 standard I4/V6/V8 engines had catylatic converters that slipped on at the Y-pipe and a ball connector at the back with a two bolt flange on the intermediate pipe.

'83-86 5.0L HO(L69) had four bolt flanges at the front and rear along with larger Y and intermediate pipes.

I don't know about TPI engines.

 

speaking of cats, were there any 3rd gen cats that are 3", or are they all smaller?...i wanted to upgrage mine to a bigger diameter converter, but I'm not sure if i can find any off of 3rd gen camaros so that it will be a direct fit...

 

Get an aftermarket cat, they flow better than stock.

$175 last time I did it. only a few months ago too.

John

 

i think a hollowed out cat would flow better...if it had a straight pipe through it then definently but prolly just hollowed would flow better...

No restriction...but kind of a small pocket...dunno

And my car already has catco cats that i dont wanna junk out to hollow them...i wanna keep these for emmisions

 

Actually as non-performance as this may sound I actually have better performance with the cat than without. The slight back pressure helped somewhat.

John