intofocuszx3

Has anyone install a header I was looking under are car it looks like a mother to change out the header. those who installed a header can you post what kind and tell how long did it take to install and was it a pain in the butt.

GTOMIKE

Piece of cake maybe 30 minutes you have to go under the car and undo 2 bolts at the flange all the rest you do from the top and the header comes out from the top all so.

I pulled mine last spring polished and ported it and put it back in big difference and you don`t have to wory about fit or leakage problems.

catdaddy137

if you are talking about the stock exhaust , what did it look like in there? was there alot of extra material from where it came out of the mold-from casting? did you match it too the gasket? i used to do it to 2 cycle scooters , with those little engines it was amazing how much difference just a little cleaning up would make. it seemed like the intake made more difference. alot of people would take too much out of the exhaust , lose backpressure and power. i don't know how much backpressure is needed on 4 cycles , i don't think they need much. have you ever seen dimples in those old 60s chevys exhaust pipes ? i wonder if they made a difference?

MONZA679

I put a header with race down pipe on mine in less than 45 min. on a rack.
Had to remove the air box off the top to tighten 2 of the bolts from the top.
I could reach them from the bottom but it was difficult.

intofocuszx3

I think u would loose back pressure if you took out the cat. but with a header and catback exahust will be find as long as you have a cat to hold some of that back pressure

GTOMIKE

[QUOTE=catdaddy137;344388]if you are talking about the stock exhaust , what did it look like in there? was there alot of extra material from where it came out of the mold-from casting? did you match it too the gasket?QUOTE]

Yes stock manifold is very restrictive take a look here.

https://www.chevyhhr.net/forums/2-2l-performance-tech-5/how-build-your-own-header-save-%24300-bucks-15656/

catdaddy137

[QUOTE=GTOMIKE;344610]i wonder why they made it like that?with those big humps? i bet would help just to take down the humps , just so they don't stick out. thanks for the thread. this doesn't mean that my 08 2.4 has aluminum exhaust manifold?

GTOMIKE

[QUOTE=catdaddy137;344635]You can not remove much without back welding you will go through the wall very quickly.You could take some off the big hump in picture #3 left side.That is where they mounted the oxygen sensor in 2006.

Lazy GM just left it there in 07 when they reloacated it to the down pipe.Too get any serious gains in flow you would have too do it the same as I did.

Ed Harvey

Will pacesetter headers part #72C-1279 work for 2006 2.2Ls hhr?

AaronSS

We don't have headers, we have a header. I realize it's common slang to use the plural form, but I've caught hell for it at meets and such. Thought I'd save you from the same.