Race Headers


FrankBarba

Permanent Vacation
Le Mans 2010 Supporter
Oct 16, 2005
544
Harrisburg, PA
I am looking to do some upgrades. I'd like to go with a set of Racing Headers, and full race exhaust. I only drive a few miles per year so i don't have to worry about smog.
 

Indy GT

Yea, I got one...too
Mark IV Lifetime
Jan 14, 2006
2,526
Greenwood, IN
Frank,
Headers look cool on the GT but it has been shown that very little performance benefit is to be had. The OE exhaust system flows pretty well.
Not sure of your intent but to each their own.
 

FrankBarba

Permanent Vacation
Le Mans 2010 Supporter
Oct 16, 2005
544
Harrisburg, PA
I was looking at weight savings (not sure how much the Manifolds weigh ?). I thank you for your help......
 

Sinovac

GT Owner
Mark II Lifetime
Jul 18, 2006
5,832
Largo, Florida
I weighed my OEM and Ford Racing headers/muffler years ago and I think the weight savings was about 50 pounds, but I'm not sure. There is an old thread on about it. The rear exit headers give you the biggest weight savings.
 

ChipBeck

GT Owner
Staff member
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Le Mans 2010 Supporter
Feb 13, 2006
5,770
Scottsdale, Arizona
Frank,

I have a set of stock manifolds sitting here so I just put them on the scale. With the aluminum heat shields installed they weigh 14.5 lbs each. I had headers on my GT and I ended up taking them off and going back to the stock manifolds. All GT headers are two piece and slip together after the top half is bolted in place. There is inevitably some exhaust leaking at that slip fit that gets worse over time. Weight savings were negligible, performance gain was negligible, and I got tired of trying to stop the slip fit leaks. I'd skip the headers but that's just my opinion.

Chip
 

B.M.F.

GT Owner
Mark II Lifetime
Jan 29, 2009
1,782
Minnesota
Stainless works makes nice headers!!
 

Sinovac

GT Owner
Mark II Lifetime
Jul 18, 2006
5,832
Largo, Florida
You will get a variety of opinions on the subject but, quite frankly, I think the cast iron manifolds look like crap in an otherwise spectacular engine compartment. In addition to the cast iron manifolds, the headers eliminate the very heavy catalytic converters. The weight loss isn't trivial, even if the HP gains are.
 
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ChipBeck

GT Owner
Staff member
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Feb 13, 2006
5,770
Scottsdale, Arizona
You will get a variety of opinions on the subject but, quite frankly, I think the cast iron manifolds look like crap in an otherwise spectacular engine compartment. In addition to the cast iron manifolds, the headers eliminate the very heavy catalytic converters. The weight loss isn't trivial, even if the HP gains are.

I agree that cosmetics are the biggest gain with headers on the GT. Removing the cats can be done with or without adding headers. I put ceramic coated Ford Racing headers on my Shelby Mustang just because they look great AND they are one piece units with no slip fit joints. Mark (FUBAR) had some one piece headers made that could be bolted on without slip fits but then he had to cover them with a heat shield as there is a component somewhere close to the headers that failed from the heat. Perhaps that's why the stock cast iron exhaust manifolds have those aluminum heat shields surrounding them.

Bottom line is that I too love the look of tube headers on a high performance engine. But for me on my GT the stock manifolds worked out better. That's just one guys opinion though. Cheers.

Chip
 

nota4re

GT Owner
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Le Mans 2010 Supporter
Feb 15, 2006
4,177
Here's the text from my post in June, 2006. (Holy cow, time flys!)



Ford Racing Rear Exit Headers Weight Savings:

Note: All weights were obtained using a better-quality digital bathroom scale. I assume that accuracy is probably within 1.0- 1.5lbs.

Stock Muffler: 55 lbs.
Stock Cats(Both): 29 lbs.
Stock Cast Manifolds (Both): 25 lbs.

Total stock exhaust weight: 109 lbs.


Ford Racing Rear Exit Headers/mufflers: 39 lbs. (complete)

Total weight savings: 70 lbs.


Also, note that the heaviest stock component is the muffler. In addition to its massive weight (strike one), is that it sits very high in the car (strike two), and, finally, as has been noted here, it blocks a substantial amount of airflow (strike three).

The Rear Exit Header System, by contrast, is not only much lighter, but the weight is also lower. The header tubes pass UNDER the halfshafts and then the collector mufflers are almost at the same height. There is now literally nothing behind the airbox. No more heat soak. Good-bye 70 lbs!
 

Sinovac

GT Owner
Mark II Lifetime
Jul 18, 2006
5,832
Largo, Florida
70 lb weight loss is huge. The other benefit that's often overlooked is that on cars with higher that stock boost, the headers will reduce boost pressure while maintaining the power gains (i.e. same HP at lower boost). So while it's absolutely true that headers on a mildly modified car won't produce big HP gains, they do allow the engine to operate under less stress. On the other hand, the GT has demonstrated that the higher boost isn't a problem at all.

My upper/lower pulley swap GT500 lost about 1.5 lbs of boost and picked up about 15-20 rwhp or so.
 

soroush

Ford Gt Owner
Mark II Lifetime
Aug 8, 2007
5,256
im in the camp that unless you are running big hp you don't need to change the exhaust. now if you want a different lock or sound or some slight weight saving (which for most of us will not make any difference its not like we are trying to get another tenth off of our time at a track) then go for it. If I could go back I would reinstall the manifolds back onto my blue car and just get a cat back system and just replace the muffler. at this point I like the cast manifolds better than exhaust.

I'm currently in the search for 93 cobra (i drove a fox in college) and I loved modifying my cars and I certainly modified my fox body back in the day but as I look for one now nothing but an all original will do :)
 

33Bravo

GT Owner
Mark II Lifetime
Nov 3, 2006
688
Minneapolis, MN
My GT has the long tube headers. They look great! I also love the sound. Was running the Ford (Borla) racing muffler. Now am running a Tubi Style muffler. Might go back to the Borla (drone).

Dyno was 673 HP (torque 687). Not sure if headers added any to this, but the sound is sooooo worth it!
 

HIRISC

GT Owner
Mark II Lifetime
Mar 14, 2007
259
Minneapolis, MN
4.0 Whipple - Header vs Manifolds

Manifolds/Cats/Ford Racing Exhaust = 735whp @ 23.3psi
Headers/Ford Racing Exhaust - 785whp @ 21.7psi

All other supporting mods the same.

YMMV
 

B.M.F.

GT Owner
Mark II Lifetime
Jan 29, 2009
1,782
Minnesota
4.0 Whipple - Header vs Manifolds

Manifolds/Cats/Ford Racing Exhaust = 735whp @ 23.3psi
Headers/Ford Racing Exhaust - 785whp @ 21.7psi

All other supporting mods the same.

YMMV

^^^^^^^^^^^^YUP 50hp and 1.5 less lbs of boost