Anyone know the specs of the stock exhaust manifold. Mostly interested in the diameter of the primaries.

Much thanks!

 

They're tiny. Maybe 1.5" tops?

 

Thanks for the reply. Anyone know for sure?

I'm researching headers and I don't want to go larger than the stock primaries by much. I just want it tuned with better lengths.

 

All aftermarket headers will have larger primaries. My stock one's sitting in the garage, I'll measure it for you in a bit. After the snowstorm dies down a bit.

 

That would be great! Let us know what you find.

 

Got my stock headers down today to measure... looks to be 1.25" piping for the primaries. Just for reference I measured my DC header too, its primaries (and probably most other aftermarket headers) measure a little under 1.5"

 

i concur, 1.25. exhaust port diameter is 1.375ID. plenty of meat to bore out to 1.625

 

Awesome. Thanks for checking. The Weapon-R is 1.5"

I'm concerned about going too large and losing low end torque.

 

If you go with a 4-2-1 design, you won't lose the low end.
I have the Weapon-R and love it.