What should I go with on exhaust manifolds?

[davbell22602]

Stock manifolds or headers on gmt400 90 3/4 ton that has 2in dual exhaust pipes. Thinking on upgrading to headers and 2 1/4 or 2 1/2 dual exhaust pipes.
Can you buy headers for a manual trany truck?

 

[Old77]

as far as I know transmission has nothing to do with if you can run headers or not. I voted headers and I'd go with a 2 1/2" set up.

 

[davbell22602]

Well I looked on places like jcwhitney, etc. and headers only fit trucks with automatic transmissions.

 

[Old77]

 

[Old77]

did ya check Summit?

 

[davbell22602]

did ya check Summit?

Crap forgot all about them. They might actually be cheaper and better quality than jcwhitney anyways.

Do I need headers that have emissions? Can I use long tube with cats or am I better off with shorty's? Does brand name matter?

 

[Old77]

Yes, you'll need headers with emissions and long tubes are far better than shorties. You can use them with cats.

 

[89Suburban]

You know my vote.

 

[davbell22602]

Yes, you'll need headers with emissions and long tubes are far better than shorties. You can use them with cats.

How do I tell if the headers have emissions or not?

 

[Old77]

Does your 90 have 02 Sensors? If so, those will need to fasten into the headers.

I'm currently looking up headers for you and will post up a couple links in this thread.

 

[Old77]

Here's a decent looking set

http://www.summitracing.com/parts/HOK-2462HKR/

In this pic of them....

You must be registered for see images attach

...on the driver side header you can see a place where the 02 sensor will go right before the 4 pipes come together (it's threaded in there). You'll need that on any set of headers you get in order to pass inspection.

Someone like C4, towman or Bucket may have good info on this as well. Hopefully they'll chime in as well.

 

[davbell22602]

Does your 90 have 02 Sensors? If so, those will need to fasten into the headers.

I'm currently looking up headers for you and will post up a couple links in this thread.

Yes I have a O2 sensor on the drivers side manifold. Thanks

 

[Old77]

Yes I have a O2 sensor on the drivers side manifold. Thanks

Perfect....then what is illustrated in post #11 shows that same thing. Can you see what I'm talking about?

 

[davbell22602]

Perfect....then what is illustrated in post #11 shows that same thing. Can you see what I'm talking about?

Yep I see what your talking about.

 

[davbell22602]

I like these but there little pricy.

http://www.summitracing.com/parts/P...ke|CHEVROLET|Model|C2500|Engine+Size|5.7L/350