Pick up some trailblazer V8 manifolds on the cheap at the pick n pull the other day. They actually fit pretty well, maybe not quite as good as the 4th gen manifolds but they are useable. I like them better than the 4th gen because they don't have any O2 ports, EGR ports or bosses and are a better looking manifold.

here's some pics.

driver side




this tab that the heat shield bolts too must be cut off.


you can see the tab a little better in this pic.






Passenger side

 

Damn those are almost perfect!

 

Interesting. I don't believe I've heard of anyone trying them before.

 

wow i wonder how they perform.seem to fit nicely with small modding.

 

The passenger side outlet I.D. Is the same size as the passenger fbody manifold basically 2.25" The driverside trailblazer manifold outlet I.D. is 2.18 vs the fbody's 2.25. The primaries are the same. The overall length seems better on the trailblazer manifolds, so they may help with torque a little more.

 

Well it looks like if you wanted to port out the outlets to 2.5 you could do it with a little room left over. Hell I would lol

 

Did you have to purchase a new Y pipe or did the stock one work?

 

Custom Y pipe is always needed unless you buy pre-fabbed headers with a Y pipe designed for a 3rd gen LS swap.

 

Now it is time to look into trailblazer headers.

 

this is very interesting, thanks for posting it up!

 

How is this a good thing?

 

Egr stuff is very rarely used on swaps, and is a cleaner look to not have it, or fab block-off plates to get rid of it.

No O2 ports allows you to weld in a bung in the pipe just after the manifold, and gives you endless placement options, instead of having to put it where factory intended.

Some swaps are tuned without any O2 sensors at all, although not a common scenario, it would be absolutely perfect for that.

 

Cool with another option/way to go. A good heat paint or maybe some spray on ceramic coating and they will look really good too :-)

 

I'm gonna get some more pics and update this a little better when I get some free time.
The lack of O2 and EGR is great for a carb conversion.
Pacesetter makes a set of 1 3/4 long tubes for a trailblazer, uncoated for sub $300. I have no clue if they'll fit a Camaro or not.