Tuned vs Non Tuned Headers - Chevelle Tech
Engine AdvertisementGeneral Engine Discussion.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
post #1 of 20 (permalink) Old Jan 31st, 07, 1:08 PM Thread Starter
Tech Team
Frank
 
Join Date: Dec 2005
Location: Pittsburgh Pa
Posts: 130
Question Tuned vs Non Tuned Headers

Hi Guys,

I read the recent thread on ceramic headers. Considering the responses, I have decided to do the jet hot route. Now for the question. The tech at jet hot said for street use I would not notice a difference between a tuned header and a non tuned. I am not planning on racing so this is for street use and ocassional hot rodding. I am going with 2" primaries with a 3 1/2" collector. Also I am leaning toward the Hooker brand. Super Comp ( which is tuned ) and the Comp. obviously non tuned. Difference in price is 200.00 between the 2. So will I see a 200.00 difference in preformance?

Thanks in Advance.
Frank
66 SS Big Block
66 SS Big Block is offline  
Sponsored Links
Advertisement
 
post #2 of 20 (permalink) Old Jan 31st, 07, 1:14 PM
Gold Member
Bill
 
Join Date: Apr 2002
Location: Winnipeg MB. Canada
Posts: 7,396
Re: Tuned vs Non Tuned Headers

Equal Length headers ..... On the street thru the mufflers .NO !!!

2" primary is pretty big do you have a 550hp motor or more ?/ if not go for 1 3/4 to max 1 7/8" primary pipe and I like a 3" collector .the smaller sizes will build velocity / heat and make more torque down low ...... Hedman makes a very nice fitting header on early BB chevelles with 3" collectors ......do a search you will find lots of info on headr sizing .....sizing all based on your engine HP and end use

66 CDN Malibu SS A51,L34,M20 Aztec Bronze
Was 439ci Straub Solid Roller Brodix RR, SOLD
,Tremec by Liberty

10.97/ 124.31 1.41 60ft
New Foxwell Power Coming
Crusin / Track video http://www.youtube.com/watch?v=fhvDGOO4JAI

Engine
CDN SS is online now  
post #3 of 20 (permalink) Old Jan 31st, 07, 2:00 PM
Senior Tech Team
 
Join Date: Dec 2005
Location: Lancaster, PA
Posts: 9,851
Re: Tuned vs Non Tuned Headers

Both headers are somewhat "tuned". I believe the selling point on the super comps was that the tube were within 5% length of each other while the comp headers are 10% length of each other. Will you notice a difference no. Probably an easier fit with the comp headers.

Ray

http://s30.photobucket.com/albums/c3...t=DSC01615.jpg
Best pass so far 9.034 at 148.10, 1.242 60'
bracketchev1221 is offline  
post #4 of 20 (permalink) Old Jan 31st, 07, 2:15 PM
Lifetime Premium Member
chris
 
Join Date: Jul 2006
Location: Georgetown, Ontario
Posts: 1,707
Re: Tuned vs Non Tuned Headers

Good advise from CDN SS.

1969 ls7 ls resto...re-creation.
Chris Stanwyck is offline  
post #5 of 20 (permalink) Old Jan 31st, 07, 9:21 PM
Lifetime Premium Member
Chris
 
Join Date: Oct 2005
Location: Wichita Falls,TEXAS
Posts: 3,200
Garage
Talking Re: Tuned vs Non Tuned Headers

Frank,

A set of 1 3/4" primary long tube headers will work just fine for a street car.

I like using DynoMax and Hedman myself. Hookers are way over priced IMO.

Good Luck!

1967 Chevelle 496BB/TH400/Dana-60 (Show and Go)
1967 El Camino 388SB/700R4/12-bolt posi (Rat Muscle Parts Hauler)
1967 C10 Short-Wide 489BB/TH400/12-bolt (The Future Shop Truck)
2008 Harley Davidson Dyna Low Rider (Stress Buster)
2015 Harley Davidson Road Glide Special (Cruiser)
2015 Chevy Silverado RS Edition (Daily Driver)



My Chevelle: http://www.chevelles.com/feature/nov98.html


C & D Performance

North Texas Chevelles
Motorhead62 is offline  
post #6 of 20 (permalink) Old Jan 31st, 07, 11:29 PM Thread Starter
Tech Team
Frank
 
Join Date: Dec 2005
Location: Pittsburgh Pa
Posts: 130
Re: Tuned vs Non Tuned Headers

Hi Guys,

Thanks for the responses. I will look into it a little more. The car is a 375 Horse with the square port heads. It does have a cam in it so lets say between 375 and 400 althought the 375 in 65 was rated at 425. I had a typo on my intial post. The difference in price is 300.00.

Thanks.
Frank
66 SS Big Block is offline  
post #7 of 20 (permalink) Old Feb 1st, 07, 8:25 AM
Lifetime Premium Member
 
Join Date: May 1999
Location: Under the hood of some musclecar
Posts: 25,051
Re: Tuned vs Non Tuned Headers

Frank,all you need is 1 3/4" primary 3" collectors for your ride.
You will NOT feel $300 worth of increased performance using anything bigger
mr 4 speed is offline  
post #8 of 20 (permalink) Old Feb 1st, 07, 10:23 AM
Gold Member
Bill
 
Join Date: Apr 2002
Location: Winnipeg MB. Canada
Posts: 7,396
Re: Tuned vs Non Tuned Headers

Quote:
Originally Posted by 66 SS Big Block View Post
Hi Guys,

Thanks for the responses. I will look into it a little more. The car is a 375 Horse with the square port heads. It does have a cam in it so lets say between 375 and 400 althought the 375 in 65 was rated at 425. I had a typo on my intial post. The difference in price is 300.00.

Thanks.
Frank

Street 396/375 square port head ....... all the more reason to not go too big, those rect heads dont make a lot of torque down low unless you have 4.10 gears stay at 1 /3/4 max 1 7/8 ...... tuned and equal length are two different things . tuned means just that, tuned to the application and end use . street with street gears you want torque down low in rpm range and also collector sizing is very overlooked in chosing a header ...... tuned for your use and engine is smaller primary like 1 3/4 and collector 3" and if you really anal collector length ....... I like the hedman since they one of few mfg. who make an off the shelf header with 1 3/4 with 3" collector .....suggestion if you want max tune use 3" exhaust pipe from header to muffler then 2 1/2 tailpipes FWIW

66 CDN Malibu SS A51,L34,M20 Aztec Bronze
Was 439ci Straub Solid Roller Brodix RR, SOLD
,Tremec by Liberty

10.97/ 124.31 1.41 60ft
New Foxwell Power Coming
Crusin / Track video http://www.youtube.com/watch?v=fhvDGOO4JAI

Engine
CDN SS is online now  
post #9 of 20 (permalink) Old Feb 1st, 07, 10:27 AM
Senior Tech Team
Bill R
 
Join Date: Aug 2002
Location: Twin Lake, MI
Posts: 2,579
Re: Tuned vs Non Tuned Headers

The term "tuned headers" is a marketing term and is about as outdated and non-descriptive as categorizing cams as "3/4 Race and Full Race".

A "tuned header" usually describes a header that has equal length (or nearly equal length) primary tubes. We all know that primary tube diameter, tube length and collector design all go into the receipe for a tuned header. Now, the chore here is to get the header "tuned" to the RPM at which the engine makes the most horsepower. A "tuned" header is actually in "tune" during a very short RPM band. (This RPM band is even shorter in a high RPM Pro Stock of Competition Eliminator class car.)

In summary - no, a "tuned" header is not at all necessary in a street or street/strip application. This is because a steet or street/strip vehicle needs to produce HP and torque throughout a wide RPM band, therefore the header would be in "tune" for a very minimum amount of time.

Bill
64 Chevelle Malibu Sport Coupe (original owner) car now has 427" BB, Jerico 5-spd. trans., Dana 60 rear end.

SAE Member (25+ years)
ASE Master Certified Engine Machinist
AERA Certified Professional Engine Machinist
engineguy is online now  
post #10 of 20 (permalink) Old Feb 1st, 07, 10:32 AM
Team Member
Joe
 
Join Date: Nov 2003
Location: Thornton, Pa
Posts: 12,777
Re: Tuned vs Non Tuned Headers

I run 1.75" X 3" Hedmans on a 10.3/1 233/236 .600/.610 lift hyd roller cammed ZZ454 motor. This motor hits harder at 3000 - 6000 RPM than any other motor combo I have ran. No question about it, the smaller tubes yield throttle response. Bought these when the car had a 396 motor and decided t give them a try with the bigger motor, glad I stayed smaller. With a 460CI motor, most likely would like a 2" x 3.5" for more power the other side of 6000. If it were me , a rec port 396 motor would get a full divided plenum intake and 1.75 primaries.
GRN69CHV is offline  
post #11 of 20 (permalink) Old Feb 1st, 07, 7:56 PM
Senior Tech Team
Tim
 
Join Date: Jul 2005
Location: pa
Posts: 1,365
Re: Tuned vs Non Tuned Headers

i used the hedman 1 3/4 x 3" in the painted version. i have raised port heads on mine. they fit ,but not good here a dent ,there a dent . also i ruined a pair of hedmans with 2 " primarys trying to make them fit. both sets were ( for my car). junk imo. my buddy used hooker comps with 2 ' x 3 1/2 " and they fit his 66 great ! did i say , yes i said great !
grovey is offline  
post #12 of 20 (permalink) Old Feb 2nd, 07, 11:45 PM Thread Starter
Tech Team
Frank
 
Join Date: Dec 2005
Location: Pittsburgh Pa
Posts: 130
Re: Tuned vs Non Tuned Headers

Hello Everyone,

Thanks again for the good responses. I picked up a summit book @ work and I noticed that most if not all header companies smallest primary tube for a 396 is the 2 by 3 1/2. I even called summit and the tech guy confirmed it. I did call Comp cams and talked to the guy that helped me pick out the cam I am currently running. I explained my operating conditions and what exhaust I am going to run. The cam has a rpm range from 1600 - 6000. He recommended a 2 by 3 1/2. So now I guess it is going to be preference?

Thanks Again,
Frank
66 SS Big Block is offline  
post #13 of 20 (permalink) Old Feb 3rd, 07, 10:24 AM
Gold Member
Bill
 
Join Date: Apr 2002
Location: Winnipeg MB. Canada
Posts: 7,396
Re: Tuned vs Non Tuned Headers

Hmmmm , lets see advice from lots of experienced BB folks here ..or advice from order taker at Summit and Comp !! What to do ??

66 CDN Malibu SS A51,L34,M20 Aztec Bronze
Was 439ci Straub Solid Roller Brodix RR, SOLD
,Tremec by Liberty

10.97/ 124.31 1.41 60ft
New Foxwell Power Coming
Crusin / Track video http://www.youtube.com/watch?v=fhvDGOO4JAI

Engine
CDN SS is online now  
post #14 of 20 (permalink) Old Feb 3rd, 07, 11:25 AM
Senior Tech Team
Sheepster. BAH!
 
Join Date: May 2006
Location: Valencia, Ca.
Posts: 9,014
Re: Tuned vs Non Tuned Headers

Ill never buy a "tuned " header again, too much of a pain as far as getting starter in, etc. If I could have bought a nontuned header in the same primary size I would have, they are much easier to install.

Quote:
This post is a duplicate of a post that you have posted in the last five minutes.
cuisinartvette is offline  
post #15 of 20 (permalink) Old Feb 3rd, 07, 11:50 AM Thread Starter
Tech Team
Frank
 
Join Date: Dec 2005
Location: Pittsburgh Pa
Posts: 130
Re: Tuned vs Non Tuned Headers

CDN,

I just posted what I found looking for a 1 3/4" primary. After not finding them readily availible I contact summit since they have ALL of the different headers listings, some of which are NOT in the catalog. The tech guy @ Comp was very helpfull and knew his stuff when consulting him on a Cam for the car. The guy that did the cam swap for me races weekly in the summer and he also reccomended 2" primary. So I am not trying to say that you guys don't know your stuff. I am merely posting what I found.

Frank

Frank
66 SS Big Block is offline  
Sponsored Links
Advertisement
 
Reply
Gear in this thread - Powered by O'Reilly Auto Parts

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Chevelle Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address. Note, you will be sent a confirmation request to this address.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools Search this Thread
Show Printable Version Show Printable Version
Email this Page Email this Page
Search this Thread:

Advanced Search
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
Headers vs. Exhaust Manifolds Hoovestol Performance 0 Apr 13th, 06 5:44 PM
headers for Vortech heads different? rancherlee Engine 1 Apr 1st, 06 1:53 PM
Ceramic headers on new SBC BBaker Engine 3 Feb 22nd, 06 9:23 AM
Powdercoating Headers? RedSS454 Performance 6 Jan 29th, 06 4:43 PM
Exhaust Theory with Tuned Headers GRN69CHV Performance 0 Jan 7th, 06 11:34 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome