I ordered some 2” exhaust tubing but the inside diameter is a little over 1.8”. Is that gonna be too small for the crossover tube and also coming off the other header. Both going into a 2.5” all the way to the t4 range. This is for a stock ford 3.7 v6.

 

It will be fine for a stock motor, and what the 3.7l can handle.

 

How much do you think that small of a inside diameter (1.8””) can handle as to how much power till it starts to be a restriction?

 

I run twin turbos with 2" pipes that are about 14" long feeding each turbo. The car makes 900hp to the tires (approx 1100 crank) so each turbo is making about 450hp. My guess is a 2" pipe can support a lot more than what I'm making if needed.

ks

 

That’s good to know. I didn’t know if the people posting about using 2” piping was going by 2” inside diameter. For mine being 1.8” inside diameter I wasn’t sure if that was going to be too small.

 

It's 2" od, but usually like 16 gauge wall thickness. You'll be fine.

 

Make a build thread I would like to see what you do with the 3.7! I used 2" pipe but ran them to a short peice of 3" before the T4 flange on my 5.0 SBF and so far I am pleased but its my first build so my bar was pretty low.

Trying to remember why I used 3" instead of 2.5". Is the 2.5" smaller than the T4? I cut a couple pie shapes out of the 3" so the circumference was the same as the inside of the T4 flange. I put it in the vice and then hammered it to fit. For the two 2" up pipes I cut a sliver out of each side so the two of them would total the circumference of the 3". Lots of vise, hammer and welding. It's not really pretty but you can not see it, and it makes boost!

 

Isn't the rule to stay below 0.4 mach?