I have a 400 B block that has been stroked to 505 in my 72 Challenger. I am using the Trick Flow 240 aluminum heads which have the exhaust ports in the stock location.
I am looking at the TTI 400SR-218 headers which are good for 600+ HP. They also have the 383-178 which are good for 400 to 600 HP.
I am leaning towards the 400SR-218 since they are the same price as the other set and I really don't know how much HP my motor will have.
Has anyone used these in an E body? Any problems?
Is there another brand I should look at?
They also have a small list of starters they say will fit with these.
I'm just looking for a little input before I pull the trigger on a $900 set of headers.
Thanks for any advice you can give!

with 505 cubes and good heads you probably want the bigger tubes.

70 has PS mini, mine fit; not the big tube one though

I run the TTI 1 7/8" headers on a '70 Challenger with B engine and Edelbrock heads which also have exhaust in (near) the stock location. They fit as advertised and have held up well for ~12 years. For my engine, which is ~550 HP these are just right.

I considered 2" tubes but TTI did not have a 2" low deck option for OEM port location at the time.

Which one is right for you depends on your build and usage... a high effort drag engine with big cam could probably use the larger tubes. There is likely mid range torque advantage with the 1 7/8 tubes.

Either way, suggest you go for the ceramic coating inside and out. It really helps control engine compartment temps so wires and other stuff hold up.

2" TTI headers had to be dimpled for the steering shaft and they touch the PS unit. If I had it to do again I'd go for 1 7/8"