Does anyone know if there is a difference in clearance or space between the Titan and Armada engine compartments. Im trying find out if any of the Titan headers will fit the Armada.

They should be the same. The header makers list the headers as fitting both vehicles.

The exhaust manifolds on the 5.6 are pretty nice as far a OEM setups go, I wonder how much gain you will see?
The stock engine performs quite well without tricks like VVT for a reason, Nissan did a good job making the engine flow.

The guys who are drag racing Titans have a lot of posts on this over at TitanTalk. They seem to be of the view that the currently available headers (all shorty style) do not improve performance. With intake and exhaust mods (in combination) usually Volant and very free-flowing and pretty loud cat-back variations especially in opening up the "Y" pipe diameter, they are getting some improvement in performance. It looks like they are picking up maybe .5 to .7 seconds with the combo and by using all the tricks to reduce weight.

That tells me that our headers are pretty good and we are not likely to benefit from what is currently available. If and when NISMO or some aftermarket supplier comes out with full-length headers, things will change. That type of design will probably really help, but there are serious emissions control issues to be solved there.

Read the posts by a guy called "The Head" over there and then make up your own mind. He has all the good mods and has been running in the 13's with nitrous. He has more experience in this area than anyone I have been able to find.

I think the headers would be a waste of money. There aren't any out there that have long enough tubes to do any good (even if they were there isn't room for them). The stock manifolds are fabricated from stainless (not rough cast iron) and look very good. A good cat back system and CAI system will help. You can buy both for far less than the price of headers.

Wait for the nismo headers. The JBA ones do nothing and are "shorties". The nismos will be long tube.

How about the stillen headers? Would they be considered short?

http://www.stillen.com/product_detail.aspx?sku=508560

How about the stillen headers? Would they be considered short?

http://www.stillen.com/product_detail.aspx?sku=508560

The Stillen headers are, indeed, long tube. This is an old thread. I think the last post before yours was about a year ago. Stillen and one other company now have long tube headers.

These are off-road use only. They eliminate the cat converters and get you 29 hp with the exhaust and I'm sure a intake as well. I hope you don't live in CA or NJ.

i know this topic is old, but have there been any new developments in the header field?

The Nismo headers are the best. They are long tube, equal length runners. The quality and fit is unmatched. On my Armada there was a 21 HP gain, measured on the dyno.

Are the nismo header street legal?
BTW...good to see ya here SCR38