I know there are threads here and there saying that the extrude honed manifold is nothing more than a stock 07 manifold.

Who knows for a fact that it is no bigger port wise than the stock 07 manifold?

Any pics of the two in comparison exist anywhere?

I can't find any comparatives.

Any help is appreciated, I really want to get one of these manifolds for my 07 LS and I don't want to put one on if I already have one.

Thank you!

 

I think you've confused the GMPP with the 07 2.2 manifold...the 07+ 2.2 mani is similar to the LSJ, but still slightly smaller. The GMPP extrude honed is larger than the LSJ, however most people think it's not worth the money compared to an aftermarket header.

 

That is true!! The only reason for the honed mani is to get a little more performance and be covered under warranty.

 

I was looking into getting the GMPP headers. So what would you guys prefer, Pacesetter or GMPP?

 

So correct me if I am deciphering this wrong.

The 2.2 manifold for 2007 is not the same as the extrude honed manifold, but the 2.0 is.

I am not worried about having max gains, I just hear the MPG goes up and having 3-4 more HP is just a bonus. I want my average MPG to stop lingering around 29 and cross over to 31ish.

I am also pondering the GMPP intake.

The catback I will use is going to be from a muffler shop unless someone locally in AZ has one for sale around $400.

 

I ported mine on my balt when i had it, Loved the sound of the exhaust noticed a little more pickup when i went WOT. But i was a slow 2.4.

 

The extrude honed manifold is very similar to the LSJ manifold, just slightly larger and smoothed ports. The 2.2 manifold is definately different.

If you want more bang for you buck then go with an aftermarket header. If you want to worry about warranty then go with the GM Performance Parts header.

 

performance wise is a aftermarket much better?

 

yes, the pacesetter will be better than the GMPP one, pacesetter is a header, the GMPP is a exhaust manifold...i run the pacesetter on my 2.2 and it gets the job done :

 

Yes...header is always better than exhaust manifold.

 

yea but how much custom work goes into the pacesetter?

 

the GMPP extrude honed manifold is a production lsj / le5 manifold that GMPP extrude and honed out for slightly larger / smoother ports for better flow.

in 07' the L61 started using the same production manifold that came on the lsj & le5 stock. this manifold has a course inside do to the casting process, along with slightly smaller ports compared to the GMPP Extrude / Honed Manifold.

hope that clears it up for you

 

this is incorrect...the 07 L61 manifold is a redesigned manifold -- it is NOT the same production manifold that came on the LSJ/LE5. In fact the 07 L61 exhaust manifold does not have the O2 sensor in it (it is in the DP) -- it will NOT replace a LSJ/LE5 manifold without finding someplace to install the HO2S-2 sensor.

 

yes but you see i have access to a gmpp manifold for 400 even and a afetrmarket one around here is no where near 500.. so i mean is a gmpp noticably worse then say a dc sports header?

 

headers have the benefit of scavenging due to the collector. Header can give as much as 10% increase in power, the GMPP -- who knows, Chevy only claimed 7% more FLOW on the LSJ with it.

You're going to drive yourself crazy over VERY minor differences. I'd bet a Cobalt with the GMPP and a Cobalt with a header and no other differences will be neck and neck down the strip! Think of it this way...the LSJ pushes 205-240 HP through the stock manifold...the GMPP (stock LSJ mani that has been honed out) is enough for the 2.2 and 2.4.

 

well thank you for the correction



x2 !

 

ok so just got off the phone so i got the GMPP mani, be in tomo at 12 or 1. 2pm tomo im gettin my custom 2.5 dp made, now more input needed i have the option to go catless or he said hes got a magnaflow high flow cat and a cherry bomb high flow cat. what do you guys think?? everything sould be done for the dyno run sunday!

bump for advice??

 

Either go catless for more power or get the Magnaflow if you want to keep it somewhat legal. How much extra for the Magnaflow over catless? It's really up to you and how much you want to spend. There will be a slight sound difference in the two as well.

Can I ask, how much are you paying for everything? GMPP extrude honed mani should cost you no more than $250-300. That's brand new. I'm looking for a used one for cheap or a ZZP mid-length header/dp for my car.

 

I would personally not go catless. But to each thier own!!

 

Quick question...

I called around to have the manifold swapped and everyone around here is saying around $250!!!! It cant take 3 hours to swap a manifold.

Does anyone know of someone in Arizona, in the Mesa region, that will do this for much less?

I want to get the manifold, but 3 hp for the price of the manifold, the gasket and bolt set plus install is IMO too much.

If I can find someone that can do the swap in an hour and a half or less, and be around $120, then its a go.

Any help is appreciated!

 

Search the site for threads on this topic...it is not hard to do yourself if you have some basic auto knowledge.

Important to remember:
New gaskets -- both the mani to head and the mani to DP
the three nuts at the mani to DP connector are HARD to get off best to use a 15MM 6 point deep socket and a LOOONNNGGG extension to get to them from under the car. do these before you remove the nuts at the mani-to-head
The mani to head nuts-on-studs are just 10MM -- DO NOT OVERTORQUE them - same goes for the heat shield to head studs. also a third heat shield bolt at base of mani.
BUY or rent an O2 sensor socket to remove and reinstall the O2 sensor in the EXT-honed mani...and use anti seize on it. Learn how to separate the O2 sensor's connector with one hand
When the job is complete do an "erase" for codes with a DTC scanner that has an erase feature. There is a warning in the factory service manual to do this when replacing the HO2S sensor or you can damage it...it just makes sense to do it -- since you removed it and reinstalled it...just to be safe.

 

They work on book time according to GM...are you asking them to install everything (manifold, dp and exhaust)? If so, $250 isn't bad...I was quoted around $200 to install all three components (and may get a discount since they are a vendor on a local forum and being about 5 miles from my house doesn't hurt either).

You can do it yourself if you have basic tools/equipment required...it's pretty straight forward...just depends on how tight/rusted on the bolts are. I just figure for me, I don't have time and I have to have my LSJ cat-back welded together anyways, so I might as well let them do it all.

 

I do a catted d\p. Your talking a few hp loss and the sound is way better with a cat unless your turbo.

 

flanges, where can i get flanges for a 2.5" custom downpipe that fits the gmpp manifold and the gmpp cat back??

haha yea well things just got complicated. downpipe isnt lookin to hot right now i cannot for the life of me find any flange to fit the header!!! fuckkkkk so i may just run the header by itself... but i was thinking could i use the flanges from my stock downpipe??? like bore the centre hole bigger to match the header and gmpp cat back??? header is kinda useless without the downpipe