About to drop in my 440. I think 1 7/8" headers are what I need, but wanted some other opinions. The main reason I am thinking about 2" is because my goal at some point is to put a larger engine in the car, and would like to re-use the headers.

But if 2" will end up losing substantial torque/hp from my current engine, I do not want them.

Here's the quick info on my setup. Street/strip. 71b. 440, ported RPM heads, 10.2:1 compression, duration @.050 intake 244 exh 252, LSA 8 degrees, Gross valve lif intake .520 exh .541, 3500 stall.

1 7/8 would be my choice for a street car.

I run 1 7/8" on my 496/Ed head and am happy with them. I think the 2" would make meaningful difference with higher flow heads & high RPM.

Considering you may want to go bigger later, I would go with the 2-inch.

I went with with 2 1/8" TTI Step Headers. They recommend them for up to 600 HP. Here is a link:

http://www.ttiexhaust.com/Category-ClassicHeaders/Subcategory/ccBigBlock-RB.htm

You might also consider looking at or calling various header manufacturers and ask their recommended size and design.

Two inch, especially with a stroker in your future

it is very common for a person to select parts for what they are thinking about in the future rather than what is right in front of them & even so with that I'd still suggest 1&7/8. I have some super stealths in front of me right now & I measured the ports & 1&7/8 is what I will be going with

I run 2 inch dyno headers on 500+ inch engines that make more than 800 hp so I doubt you need them on a mild perf street car.

PipeMax will tell you to put 1 3/4 headers on a mild 440. If you look at the size of a big block exhaust port you'll see that a 1.50 inch header pipe will work. I don't thin anyone builds them that small but that is roughly what the size of the port is.

thanks for all the replies. I need some clarification, if 1 7/8 is the right choice for this engine, what exactly do I lose by going 1/8" too big? Is it a loss of tq, hp or both? Is the loss down low, high or across the entire rpm range? If it is a loss, how much are we talking?

Also, a few things I forgot to mention, I will be adding nitrous to this engine. Not alot, probably 200 shot.

When I had 2" headers on the 470 in my 4000 lb charger I noticed a drop in part throttle responsiveness.Anything less than full throttle it felt lazier than the 1 7/8.I was also running 4.10 gears.
For a heavy car torque is king.2" will make more peak hp and TQ and maybe at a slightly higher rpm.Unless it is a dedicated track car I will take the torque of the 1 7/8 over the 2" hp.Make sure your exhaust system is free flowing for either.
On a 200 shot I would be looking for a cam ground for nitrous.

My cam and my compression are why I chose a smaller shot. The engine is already built and the nitrous wont be used very often.

Im getting the TTI headers, and the guy I called there basically just repeated what was on their web page, that 1 7/8 was for 400-600hp, and 2" was for 600 and up.. I wasnt satisfied with the generic description so thats why I posted. Thanks for the explanation!

If you go on the TTI website, you will notice that the 1 7/8" headers are layed out differently than the 2".

Depending on what car you are installing them on, one may fit better than the other. I have an e body and the 2" clear the steering linkage fine where as the 1 7/8" are very close.

1-7/8" were good enough for me to go 11.0s w/ a 440 E-body. I only switched to 2" when the car was fast enough to run 10.5s.

You don't have a 2" combination and will be happier staying w/ the smaller headers, unless you make MAJOR changes to your combination.