Do I really need the headers?
Thread Starter
Burning Brakes
Joined: Jan 2006
Posts: 1,019
Likes: 18
From: St. Louis MO
Do I really need the headers?
I am working on a 1980 4speed. 350 L-48. No new cam just have to get exhaust fixed. I am going with true duals. Would the headers make enough of a difference to do all the work. I will some day change the motor. 
Drifting
Joined: Apr 2002
Posts: 1,716
Likes: 4
From: New Baden Illinois
Yes, exhaust was the biggest limitation on the L48, then the cam, then the heads.
You should feel a difference with an exhaust change.
BTW, I had a buddy whose 1980 looked exactly like yours, except it was an automatic.
You should feel a difference with an exhaust change.
BTW, I had a buddy whose 1980 looked exactly like yours, except it was an automatic.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
If it's a stock L48 you will see minimal performance gains...but the sound and coolness factor will go way up. I love headers. I have side mount headers on my Vette and side pipe exhaust...but long tube headers are very cool, and sound amazing when finished off with a pair of Magna Flows.
Safety Car
Joined: Aug 2001
Posts: 3,683
Likes: 201
From: Waterford Mi
Corvette Fever di an aticle about this back in 1996. After making changes to an L48 engine they were able to show an increase of 150HP. This took a lot of work such as openning up the heads for larger valves, adding flat-top pistons, and new crank and rods. Then end result was put on a dyno with headers and then agian with stock exhaust. Only 3 HP was gained with the headers. Bottom line is that if you aren't pushing for a race car then the change is minimal.
But the cool factor is large.
But the cool factor is large.
Le Mans Master
Joined: Apr 2005
Posts: 6,346
Likes: 418
From: Seattle Area WA
Headers won't do a darn thing for your stock L-48. Your 2" rams horns exhaust manifolds are more than adequate for a true dual exhaust system topped off with some Dynomax Turbo or Magna flow mufflers. I'd rather spend the extra money and install a X pipe or an H pipe.
When you get around to changing the motor, you can cut the pipes and install headers then or go to 2 1/2" rams horn exhaust manifolds depending upon your motor build.
When you get around to changing the motor, you can cut the pipes and install headers then or go to 2 1/2" rams horn exhaust manifolds depending upon your motor build.
Le Mans Master
Joined: Oct 2004
Posts: 5,269
Likes: 54
From: Orlando Florida
St. Jude Donor '05
If you replace the engine some day with something more powerful you will benefit from the headers. I'd prefer to do this now - you're saying you work on the exhaust anyways ... the sound alone is reason enough to install headers and a true dual exhaust 
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
I agree, headers alone and stock exhaust won't do much. But headers and free flowing 2.5 in. exhaust will give a nice performance increase
Racer
Joined: Feb 2007
Posts: 342
Likes: 0
From: Onley VA
The intake and heads are really the limiting factor on your motor (the cam is also but we're only talking airflow right now), but changing to headers now while you're doing the other exhaust work would be the most efficiant thing to do. They will make a little power and sound way better but the main thing is that when you make other changes they will allready be there. While the power gains will be minimal for the headers, it will allow other up grades to work much better. I saw a dyno test were an intake swap with ex manifolds only gave a little HP (aroud ten if remember right) but the intake swap with headers was worth over 20 HP. Just remember, headers never hurt anything but your knuckles.
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Racer
Joined: May 2006
Posts: 264
Likes: 0
From: Fort Myers, Fl / St. Paul, Mn
I just took my headers off and reinstalled the ram horns. I really can't speak about the HP loss but I do know about the heat. I live in Florida where the summer heat is enough without the extra heat from the headers. The air conditioner works fine for the first 5 miles of so but then the headers get hot and it's like being in that pizza oven. If the summer temp in your area gets in the mid 80's you will notice the difference. Insulation probably helps but is not the cure. I have a well insulated floor and firewall.
I also like the exhaust sound better with the cast iron manifolds. It's hard to explain but it has a different tone that I like better.
I also like the exhaust sound better with the cast iron manifolds. It's hard to explain but it has a different tone that I like better.
Thread Starter
Burning Brakes
Joined: Jan 2006
Posts: 1,019
Likes: 18
From: St. Louis MO
i THINK i WILL SAVE SOME MONEY NOW AND JUST DO THE EXHAUST WITH THE STOCK MANAFOLD. wHEN i CHANGE MOTOR i WILL USE THE HEADERS. iT SEEMS THAT WITH THE HEADERS CHANGING SPARK PLUGS IS A PAIN. sorry for the caps...
Racer
Joined: May 2006
Posts: 264
Likes: 0
From: Fort Myers, Fl / St. Paul, Mn
About spark plugs - when I had headers (Hooker) I was able to change all my plugs from the top but now that I have stock manifolds I can't even see them. I haven't had to take them out yet (put in Bosch platinum plugs in before I installed the manifolds) but it seems like it will be easier from under the car.