ATR headers question

[Turbo V6 231]

hello,
was curious if someone could help me with this, I have a set of headers and I believe they are ATR ones.
the only question I have is did the ATR headers have oval shaped ports where the flanges connect to the heads, not rectangular like most have.
any help here would be appreciated, I have seen pictures both ways and both were supposed to be ATR headers, just curious if there were 2 different types and why??
and could I still use them on these cars, 86-87 turbo intercooled buicks, will they seal properly??
thanks Brian

 

[ShaunDonWe2]

Post pics

 

[Turbo V6 231]

here are a few pictures of the headers, I know there has been some welding repairs done to these ,and doesnt look the best, but the factory welds look good, I just need to figure if they are atr's and why they have oval ports and not rectangular ones, thanks again

 

[kidglok]

The early ATR's had round ports

 

[Turbo V6 231]

is there a reason why?? I am not sure they will seal with rectangular heads??

 

[kidglok]

is there a reason why?? I am not sure they will seal with rectangular heads??

I don't know why, I had a set like that and they wouldn't seal for shit.

 

[CGASTON]

The early ATR's had round ports

How early? I have ATRs and nought them around 1996 and they are retangle.

Sent from my iPhone using Turbo Buick

 

[Turbo V6 231]

these are definitley old looking, but if I could use them would be good, was thinking about cutting off the flnges and welding on new ones,I saw RJC sells the rectangular ones, wonder why ATR would sell oval/round ported ones when the heads don't match, thats what has me questioning this??
thanks

 

[T-CHRGD]

I'm not familiar with Stage II motors, but I think they are Stage II headers.
Post a picture in the Stage II section. I'm sure they will know if they are.
My early ATR headers are rectangular port.

 

[TurboDave]

I'm not familiar with Stage II motors, but I think they are Stage II headers.
Post a picture in the Stage II section. I'm sure they will know if they are.
My early ATR headers are rectangular port.

Definately NOT SII headers.

Been a lot of sloppy re-welding done on those. I don't know if I'd re-use them or not.

Could be later KB headers when he started copying the ATR style.