Here is a list of performance parts for your LS4. This thread is based on bolt-on items that the typical gear head/backyard mechanic can do on their own.

A few notes!
I strongly recommend getting dyno tuned. Avoid canned tunes unless the tuner has away of data logging, and making corrections. A canned tune is nothing more then an assumption.

HP tuners and EFI live, is the best option, for the highly skilled. If you are considering using this advanced tuning software, then be prepared to learn at your own risk. I recommend searching https://ls1tech.com/forums/pcm-diagnostics-tuning-7/ for more information, and using forums on the manufactures website to gain incite.

Please understand, that I am not trying to be one sided. There are as many "bad" tuners as their are "good" so be cautious. I highly recommend using Diablosport tuners because of Lewis Eaton (Diablew). He is able to data log, and make the proper corrections.

Do not be affraid to use the search box. I have done my best at providing additional information.

 

Induction

Hot air intake:
http://www.knfilters.com/search/prod...x?Prod=63-3059 Fits all models


Cold air intake:
Monte Carlo SS http://www.coldairinductions.com/sto.../2006?___SID=U
Impala SS http://www.coldairinductions.com/sto.../2006?___SID=U
GXP http://www.coldairinductions.com/sto.../2006?___SID=U


http://www.wbodystore.com/air-induct...e-system-.html


http://intense-racing.com/Merchant2/...=LSx_Induction


Throttle body spacer:
https://ls1tech.com/forums/ls4-perfo...verdict-3.html


Ported LS4 intake manifold:
http://www.fasterproms.net/ Additional info https://ls1tech.com/forums/ls4-perfo...-manifold.html

 

Exhaust

Doug Thorley Headers:
http://dougthorleyheaders.com/produc...productID/1052


Additional info
https://ls1tech.com/forums/ls4-perfo...ct-update.html

https://ls1tech.com/forums/ls4-perfo...group-buy.html

https://ls1tech.com/forums/ls4-perfo...e-headers.html

https://ls1tech.com/forums/ls4-perfo...tures-lol.html

Downpipes:
http://shop.zzperformance.com/store/...Downpipes.aspx This DP should fit all LS4's


Hogan performance downpipes, are no longer being produced https://ls1tech.com/forums/ls4-perfo...downpipes.html

MagnaFlow Catback exhaust systems:mag MagnaFlow Likes to change their Part numbers around, so be cautious when viewing the links posted below. Monte, and Impala will have single tips
Monte Carlo SS http://www.magnaflow.com/02product/s...one=all&id=642
Impala SS http://www.magnaflow.com/02product/s...one=all&id=577
GXP http://www.magnaflow.com/02product/s...ne=all&id=9657

 

Tuning

Diablosport tuning:
2005-2008 Monte Carlo SS, Impala SS, GXP http://diablosport.com/index.php/product-search

Additional info
http://www.diablewtune.com/
http://intune.diablewtune.com/
http://trinity.diablewtune.com/

 

So I've been trying to find a throttle body spacer for my 07 pontiac grand prix gxp. But all of the links on here won't bring me to a place to actually buy it. Does anyone know where to get one? Any help would be great. Thanks.

 

you won't net any worthwhile gains spend money where it matters a intake manifold swap and tb upgrade

 

This is one, there are others as well.

http://www.ebay.com/itm/Hamburgers-P...RWoA-I&vxp=mtr