L-48 Mods?
Thread Starter
3rd Gear
Joined: Feb 2005
Posts: 3
Likes: 0
L-48 Mods?
Just bought a 76 with the L-48 and want to do some minor mods on it. Engine was rebuilt 17k ago and it is the original so i cant bring myself to break into the thing yet. The car has the original carb on it and i am thinking of replacing it. Other Mods in mind are the Distributor, and exhasut. Has anyone already gone threw these mods on a L-48 and what where their findings with different brands. 
Last edited by Bilen69; Feb 4, 2005 at 08:58 AM.
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
Funny, the original rebuilt engine L48 in my '72 here had lo miles on it too, garage queen, the biggest single improvement for fuel economy and power/performance/driveability was the addition of a dead stock L98 DPFI system.....
In more than a few ways, I wish that drivetrain was still in the car, not as much power as I have now, but it was damn smooth....had an easy 250 hp...maybe more....car was a dream to drive with that Muncie, most often starting out in 2nd gear, and going to 4th in traffic at about 20-30 mph....thing NEVER complained, just smooth as silk, and torqued right on up there....
NO carb combo can do that....not and get 24 mpg either, 19-20 around town.....
GENE
In more than a few ways, I wish that drivetrain was still in the car, not as much power as I have now, but it was damn smooth....had an easy 250 hp...maybe more....car was a dream to drive with that Muncie, most often starting out in 2nd gear, and going to 4th in traffic at about 20-30 mph....thing NEVER complained, just smooth as silk, and torqued right on up there....
NO carb combo can do that....not and get 24 mpg either, 19-20 around town.....
GENE
Race Director
Joined: Mar 2001
Posts: 11,322
Likes: 1
From: Living in the Hartland
Easy
1. Tune up
2. Recurve distibutor adv
3. Free flow cat (or no cat if you can/care to)
Little harder
4. Headers and dual exh
5. New heads, intake and cam.
Do em that order for best results
1. Tune up
2. Recurve distibutor adv
3. Free flow cat (or no cat if you can/care to)
Little harder
4. Headers and dual exh
5. New heads, intake and cam.
Do em that order for best results
Le Mans Master
Joined: Jul 1999
Posts: 9,206
Likes: 17
From: Sewell NJ
Originally Posted by Fevre
Easy
1. Tune up
2. Recurve distibutor adv
3. Free flow cat (or no cat if you can/care to)
Little harder
4. Headers and dual exh
5. New heads, intake and cam.
Do em that order for best results
1. Tune up
2. Recurve distibutor adv
3. Free flow cat (or no cat if you can/care to)
Little harder
4. Headers and dual exh
5. New heads, intake and cam.
Do em that order for best results
Burning Brakes
Joined: Jan 2004
Posts: 868
Likes: 2
From: Olney MD
Originally Posted by Bilen69
Just bought a 76 with the L-48 and want to do some minor mods on it. Engine was rebuilt 17k ago and it is the original so i cant bring myself to break into the thing yet. The car has the original carb on it and i am thinking of replacing it. Other Mods in mind are the Distributor, and exhasut. Has anyone already gone threw these mods on a L-48 and what where their findings with different brands.
the first things i did was go for beauty under the hood, valve cover, chrome air cleaner, then next came the exhaust - sidepipes ahhhhh!! check out my webpage www.cardomain.com/id/1funvet
Melting Slicks
Joined: Jan 2004
Posts: 2,672
Likes: 1
From: New Cumberland PA
I really do not have a grasp as to what you want to acomplish, what your skills are, or what you are budgeting. If you're looking to get the back tire to spin easily, then it will need more than a tune-up but don't disregard that. No matter what engines mods are done, they will not see their full potential until the exhaust is freed up. There was an old, old post that stated this alone would add 50hp, headers and true duals. The next big step would be the top end of the engine: cam, heads, and intake. Depending on which cam you choose those improvements to the L48 will out perform any small block chevy GM installed in a C3.
Thread Starter
3rd Gear
Joined: Feb 2005
Posts: 3
Likes: 0
Originally Posted by mandm1200
I really do not have a grasp as to what you want to acomplish, what your skills are, or what you are budgeting. If you're looking to get the back tire to spin easily, then it will need more than a tune-up but don't disregard that. No matter what engines mods are done, they will not see their full potential until the exhaust is freed up. There was an old, old post that stated this alone would add 50hp, headers and true duals. The next big step would be the top end of the engine: cam, heads, and intake. Depending on which cam you choose those improvements to the L48 will out perform any small block chevy GM installed in a C3.
I have had some experience with engine work. a couple years ago took a 1985 chevy scottsdale and ripped all the fuel injection out and put a ZZ3 engine (alu heads Ahh the moths were coming out of the wallet) in it with dual carbs. Not sure why we chose that model but was a fun project.
Budget? I now own a classic car is there really such a thing.
The vette will NOT go on the chopping block like that project did. Just want to get it to around 250 horsepower or so.
Thank you all for your welcome comments. Im sure i will be talking to you all soon.
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Pro
Joined: Sep 2004
Posts: 579
Likes: 0
From: North Texas
Originally Posted by Fevre
Easy
1. Tune up
2. Recurve distibutor adv
3. Free flow cat (or no cat if you can/care to)
Little harder
4. Headers and dual exh
5. New heads, intake and cam.
Do em that order for best results
1. Tune up
2. Recurve distibutor adv
3. Free flow cat (or no cat if you can/care to)
Little harder
4. Headers and dual exh
5. New heads, intake and cam.
Do em that order for best results
Racer
Joined: Apr 2001
Posts: 395
Likes: 0
From: Shoreline WA
The first thing you should do is download and read Lar's papers on setting your timing and Q-Jet carb. Replacing distributor or carb at this time is would be unwise since there are other things that can be improved like the mentioned exhaust that would further increase your perfomrance. The carb and HEI distributor are more than adequate for your engine even with improved exhaust, intake manifold and heads.
After proper igintion and fuel setup, then I would ehance the exhaust. Following this, then would come intake, cam and heads.
Mike
After proper igintion and fuel setup, then I would ehance the exhaust. Following this, then would come intake, cam and heads.
Mike
Intermediate
Joined: Sep 2004
Posts: 35
Likes: 0
From: Woodbridge VA
On exhausts...... I have my 78PC/L48 registered as antique to avoid the emissions.
Since I never plan on ever getting rid of this devil, I figured it would be a cool addition to add a true duals.
Is this exactly what I should be looking at ? This should be something I can add myself correct ?
http://www.madvet.com/shop?frame=4.36.1267
603-840 1974-79 Stainless Steel, 2.5" Pipe, 2" Manifold, Auto Trans., Small
As for the mufflers, I will need to do a little more research.
I would like something with a nice rumble as discussed in another thread. I know my neighbors will appreciate me looking for something kinda quiet till I GET ON IT..
Since I never plan on ever getting rid of this devil, I figured it would be a cool addition to add a true duals.
Is this exactly what I should be looking at ? This should be something I can add myself correct ?
http://www.madvet.com/shop?frame=4.36.1267
603-840 1974-79 Stainless Steel, 2.5" Pipe, 2" Manifold, Auto Trans., Small
As for the mufflers, I will need to do a little more research.
I would like something with a nice rumble as discussed in another thread. I know my neighbors will appreciate me looking for something kinda quiet till I GET ON IT..
Melting Slicks
Joined: Dec 2000
Posts: 2,198
Likes: 2
From: Eastern Connecticut
Originally Posted by SLine78
The first thing you should do is download and read Lar's papers on setting your timing and Q-Jet carb. Replacing distributor or carb at this time is would be unwise since there are other things that can be improved like the mentioned exhaust that would further increase your perfomrance. The carb and HEI distributor are more than adequate for your engine even with improved exhaust, intake manifold and heads.
After proper igintion and fuel setup, then I would ehance the exhaust. Following this, then would come intake, cam and heads.
Mike
After proper igintion and fuel setup, then I would ehance the exhaust. Following this, then would come intake, cam and heads.
Mike
Nothing wrong with a q-jet and HEI that a little tuning can't fix. Joe
Melting Slicks
Joined: Oct 2003
Posts: 2,033
Likes: 1
From: Prescott Arizona
Originally Posted by xsecurity
On exhausts...... I have my 78PC/L48 registered as antique to avoid the emissions.
Since I never plan on ever getting rid of this devil, I figured it would be a cool addition to add a true duals.
Is this exactly what I should be looking at ? This should be something I can add myself correct ?
http://www.madvet.com/shop?frame=4.36.1267
603-840 1974-79 Stainless Steel, 2.5" Pipe, 2" Manifold, Auto Trans., Small
As for the mufflers, I will need to do a little more research.
I would like something with a nice rumble as discussed in another thread. I know my neighbors will appreciate me looking for something kinda quiet till I GET ON IT..
Since I never plan on ever getting rid of this devil, I figured it would be a cool addition to add a true duals.
Is this exactly what I should be looking at ? This should be something I can add myself correct ?
http://www.madvet.com/shop?frame=4.36.1267
603-840 1974-79 Stainless Steel, 2.5" Pipe, 2" Manifold, Auto Trans., Small
As for the mufflers, I will need to do a little more research.
I would like something with a nice rumble as discussed in another thread. I know my neighbors will appreciate me looking for something kinda quiet till I GET ON IT..
Melting Slicks
Joined: Oct 2001
Posts: 3,025
Likes: 12
From: Pleasant Grove AL
My 75 vert is the original L48 with about 9.8:1 compression, "street performance" hydraulic cam, 2.5" ramshorn manifolds, 2.5" true dual exhaust with no cats, Edlebrock manifold and carb. Runs better than my 67 L79. Gas mileage sucks. Can't keep right foot off accelerator. Thinking seriously about going to TPI system.
