header and exhaust options, for 98 cobra - Ford Mustang Forums : Corral.net Mustang Forum
LinkBack Thread Tools Display Modes
post #1 of 4 Old 09-14-2009, 07:33 AM Thread Starter
Registered User
Trader Feedback: (1)
Join Date: Jun 2007
Location: greenville, s.c.
Posts: 50
header and exhaust options, for 98 cobra

new to my '98 cobra ( and 4V's in general)

i am looking for some headers : this is to be a road-course racing car.

'98 b-headed engine, which will remain naturally aspirated.
i can forsee p/p'ing the heads, and valve/cam jobs sometime next year.
also planning on a full MM maximum grip box, including the k-member.

***looking to maximize area under the hp & torque curves, not peak numbers.***

(1) are LTs what i want???
(i don't want any ground clearance issues, either)
would mid lengths be better for road racing?
or, (perish the thought) shorties??

(2) if LT's are the answer, 1 5/8" or 1 3/4"??

(3) what size for the rest of the exhaust system, 2.5" or 3"??

(4) x or h pipe? (the throatier the sound, the better, but again, i want to focus on area UNDER the dyno curve, with road racing in mind)

going with an off-road mid-pipe, since i live in a state which doesn't perform emissions testing (or even vehicle inspections for that matter)


docstang is offline  
Sponsored Links
post #2 of 4 Old 09-14-2009, 02:35 PM
Registered User
Diesel's Avatar
Trader Feedback: (0)
Join Date: Feb 2001
Location: Ft. Walton Beach, FL
Posts: 377
You might want to consider JBA shorties as an option. I have them and have a broad powerband. Bob Cosby also had great results with them on his Cobra. I don't see many other 4.6 cars with longtubes that exceed it without considerably more money and mods than what I have invested.

I recommend the JBA's because it will be considerably easier to replace your clutch, transmission, etc. Many of the longtubes need to have the passenger header removed if you need to remove your transmission.

My dyno sheet

Kooks Long tube vs JBA Shorties on 4.6 engine.

Stick with a 2.5" exhaust. You won't see much if any gains with 3" until you get to the 400rwhp range. Your money is better spent elsewhere. I don't think there is a significant different between an x or h pipe either.

Just remember that some tracks have sound decibel limits. Don't get too aggressive that you will be kicked off the track.

Get a 3.73 rear gear and that should also help with improving torque to the wheels, yet still retain enough top end without running out of gear.

2012 Race Red GT
1998 Black GT (Open Track car) - TF 44cc Heads/Aviator SB, HP cams, BBK shorties, Delta Force tuning, MM Panhard LCA FCA Full subs CC plates coilovers, Koni Yellows, drop spindles, Brembo/Cobra brakes, 3.73 gears, truetrac diff
Track Videos - http://www.youtube.com/cxavier68
Diesel is offline  
post #3 of 4 Old 09-14-2009, 04:01 PM
Registered User
Jack Hidley's Avatar
Trader Feedback: (5)
Join Date: Apr 2000
Location: Danville, CA USA
Posts: 3,016
3" exhaust and full length headers are going to be a lot heavier.

The main problem with full length headers and road course driving is this: Heat. The more surface area the headers have, the more heat they will transfer to their environment. This heat ends up against the firewall and floorpan right where your feet are. In street driving and 10 seconds of wide open throttle at a drag strip this may be tolerable. However run the engine at near full throttle for 20 minutes and things will be very different.

I would look at shorties or mid length headers.

Jack Hidley
Maximum Motorsports Tech Support
Jack Hidley is offline  
Sponsored Links
post #4 of 4 Old 09-15-2009, 01:11 AM
Registered User
Trader Feedback: (0)
Join Date: Feb 2005
Location: San Jose, CA
Posts: 326
Originally Posted by Jack Hidley View Post
However run the engine at near full throttle for 20 minutes and things will be very different.
If you don't get the floor pan hot enough to melt the soles on a cheap pair of sneakers, you're not using the motor.

( I usually warn passengers to keep their shoes away from the transmission hump. )
SteveL1994 is offline  
Sponsored Links


Quick Reply

Register Now

In order to be able to post messages on the Ford Mustang Forums : Corral.net Mustang Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

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


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Similar Threads
Thread Thread Starter Forum Replies Last Post
Header options! Adam95GT 94/95 Tech 28 08-06-2009 10:52 AM
Options on the SLP Loudmout Exhaust for 99-04 Cobra xDisciple SVT & DOHC 3 06-07-2004 10:58 AM
Exhaust options for 97 BBK LT Cobra teq SVT & DOHC 4 11-21-2003 05:42 PM
What are my header options? ClassifiedRide GT & SOHC 6 02-13-2003 01:27 PM
Anybody know the size of the header studs on stock Cobra exhaust manifolds? Slithering_Joe SVT & DOHC 5 11-10-2002 09:47 AM

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