Mast 275 Cathedral port exhaust port?????
#1
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I have these heads on my current motor. I am looking to swap out the 2005 Kooks 1 7/8" headers I have for a 2" Kooks race header. Since the exhaust port is the same as the LS7 Mast head, does that mean I should opt for the LS7 exhaust port option on the Kooks headers?
http://www.kookscustomheaders.com/show.php?pid=841
vs the regular 2".
http://www.kookscustomheaders.com/show.php?pid=840
Hoping this will free up a little more power with the Kooks True Duals.
I have looked at the exhaust ports and they are not totally round, but do have a slight D shape.
Hopefully someone from Mast or a dealer can offer some insight. Kooks was not sure.
http://www.kookscustomheaders.com/show.php?pid=841
vs the regular 2".
http://www.kookscustomheaders.com/show.php?pid=840
Hoping this will free up a little more power with the Kooks True Duals.
I have looked at the exhaust ports and they are not totally round, but do have a slight D shape.
Hopefully someone from Mast or a dealer can offer some insight. Kooks was not sure.
#2
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Just an FYI.
I talked to Mast today and was told that yes the exhaust port is based on an LS7 exhaust port, but they are different enough that a full round flange on the header will work better and they in fact use a kooks 2" header for the dyno.
So now I know what to order.
I talked to Mast today and was told that yes the exhaust port is based on an LS7 exhaust port, but they are different enough that a full round flange on the header will work better and they in fact use a kooks 2" header for the dyno.
So now I know what to order.
![Grin](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_grin.gif)