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Exhaust Headers

D

darkdata

GUEST
:cautious: Greetings Fellow Av'ers. I am getting ready to modify the last part of the exhaust system that I think is left. So far I have 2 Flowmaster 40's with dual diagnaly out the back, I am told that changing the headers would really help my system breath better, along with giving more HP/Tor/MPG. I see several topics on headers by Gibson and some by "The other guys" well I know just about nothing when it comes to headers so any insight someone could provide would be great, what do you look for when choosing, etc.. Thanks for the help.
Dark
 
darkdata,,,

TOG headers seem to be the best choice... Stick with a long tube design on these trucks... Don't scrimp in this area... Cheap headers will give you fits with our aluminum heads... The only others I would recommend would be the ASM long tubes... I hear SLP is developing a set too... Also, 3/4" tubing will be better than 5/8" ... 3/4" long tube headers should be good for 15 to 20 RWHP if you currently have a cat back exhaust ... Very good mod ... The long tubes should bring in some bottom end power also ... If you have a true dual set-up, I hope you have an equalization pipe somewhere already to balance out the exhaust... Some call it an X pipe, H Pipe, EQ Pipe, whatever... If you don't have this now, I would do it before you do headers... Keep the pipe no more than half-way back on the exhaust system... (this is why I don't run a true dual set-up anymore... The EQ pipe usually makes things hard on the limited space we have already... Besides, a full single 3" kit will do more on bottom, and mid power... The true duals will only shine on top IF you haven't gone too big on piping... But this might just be 5 to 10% subjectively... )

11H
 
Edelbrock will be coming out with headers for the 8.1 in the next 2-3 months also. This is the way I am going to go.
 
Aegis,,,

Is Vic gonna be down to earth on price?

I hope so... Seems like some bar stock, and 3/4" piping can't be worth $1,000 plus dollars... I can't understand why it costs so much for the GOOD headers... Almost would rather have the Stock nice sealing exhaust manifolds, and save the $1000 towards a supercharger...

11H
 
I have always had real good luck with JBA headers...I am not sure if they have anything for the 8.1, but I will be getting them in a few months....
 
Thanks all for the fast responses... From what I have been reading so far TOG headers seem to be the best choice... Since I will not be able to do this mod until Jan. Feb. time frame, its a christmas thing, that should give time for the other companies to come out with their headers... However I am still a little unclear about how to choose. I understand the longer pipes are better for mid power range, and based on where the power band is for the AV low to mid is were you want the power. I installed a dual system out of preference, when it was intalled the guys at Minekee said because my system was dual all the way to the original mufflers that I will not need a equalization pipe. They said the Cat converter is playing that roll since it is a dual in and dual out. Please advise, I don't want to put the headers in and cause problems by not having a balanced system. As for the size of the pipe, I believe I am running 2.5 inches all the way thru, except for the last 18inches or so and I have a 3inch flared tip, stanless steel. Please advise. Thanks all.
Dark
 
Dark,,,

I realized after reading your post you have the 2500 ... I am not immediately familiar with the oem set-up... But if you say there is a cat that has a dual inlet and dual outlet, then it might be ok, IF... That cat shares exhaust gasses from both pipes in and out ... If it doesn't, then you will need an EQ crossover somewhere ... The reason for an EQ pipe is to not have one side of the motor running different exhaust velocities and effeciency compared to the other... The only time you won't need an EQ pipe is in a perfect world when you are running identically measured and bent pipe on both sides... (But most V8's run differently on each bank... The left 4 could be making 300 cfm of flow, and the right might be making 320 cfm of flow)... If this is the case, even if the pipes are identical, you would want an EQ pipe for insurance... Because the truth is, no motor has "identical" output on both sides... The EQ pipe is really popular on new vehicles because space limitations require unequal piping in length, and bends... It's pretty much protocol... Unless your cat is designed like I said above...

2.5 pipe is great for your motor... Good choice...

11H
 
I've been thinking JBA Cat-4wards.
Truck performance.com, $475 shipped. I had them on my '00 Silverado and liked them. I've just been having a hard time spilling out that credit card number!
Free shipping on them till Friday.

WW

www.Truckperformance.com
 
I am very pleased with my new headers and cat-back exhaust. I don't doubt this is one of the finists mods for realizing (feeling) the power of the 5.3.

I picked Gibson and am plenty satisfied although I imagine JB and others are just as good. I was impressed with customer service at Gibson. Price for headers and Swept-back exhaust (recommended by G for best horsepower, torque, etc) was around $615 plus installation.

Highly recomment headers and exhaust of some make. If you are concerned of exhaust being to loud, don't be. You may even be disappointed in sound (not loud enough when you want to show-off).

Happy New Year!

bb
 
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