California 91 744 non turbo with rex/regina. O2 sensor on cat

If I am replacing new both the header pipe and cat together, does it matter if I buy a regina or bosch header pipe?

What is really the deference between the two pipes, all the pics look the same? Length, curvature, manifold bolt pattern?

I can get the Bosch pipe for cheaper and I need to make sure which ever system I get it either has the O2 port on the pipe or cat.

Thanks in advance BB

i am not a 740 expert i only have one a 760 and a turbo at that. nevertheless i am fairly sure the NA 740's are regina and the turbos are bosch for the year you seek parts for. this means the header is going to be larger and bent different on the bosch pipe than the regina model. the bosch modeled header will also fasten to the exhaust manifold COMPLETELY different than the regina pipe because of the presence of the turbo at that point.

i think you are out of luck on this one.

the 91 740 na's could be bosch a well, mostly all in Cali. I was told by the previous owner they believe this car was brought in thru Canada.

I do know the turbos' are different. Got my mint 92 740 turbo wagon right next to this car in the garage.

I will wait for some more responses.

Thanks for yours

http://www.eeuroparts.com/Main/PartDetail.aspx?id=3514974

if you look at the bottom of the page you see this is specifically applied to regina cars for the year in question you have.

YET, it fits many years previous to regina equipment as well and that can ONLY mean bosch.

logic would suggest this pipe will fit your 91 with bosch just fine and is likely for practical purpose identical to the pipe stated as bosch only for a 91 740 na.

ergo, if it was me i would buy the cheapest header for a non turbo non egr for that year irrespective whether they say its for regina only or bosch only.