Questions about L82
Thread Starter
Racer
Joined: Nov 2006
Posts: 435
Likes: 7
From: Wake Forest NC
Questions about L82
I remember as a teenybopper eyeballing a L82 in a showroom in 1975. The sticker, as I recall, told of a beefy bottom end. After recently reading specs on a L82--202 valves, a decent cam, large exhausts, etc; why only 205 HP? Did the cat rip off that much HP?
Race Director
Joined: Sep 2001
Posts: 10,560
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From: Wellington, FL
St. Jude Donor '11 thru '25
Vettes during that era had very low HP due to, among other things, regulated emission equip. that was mandated by the Gov. The '75 was the real drop and it lasted well into the '80's. The '74 was the last of the 454ci, 270 HP.
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
As I remember, I think the insurance industry had a play in the HP reduction also, as rates for coverage really started to go thru the roof for cars with high end HP ratings.
Tech Contributor
Joined: Aug 1999
Posts: 15,175
Likes: 3,987
From: Connecticut, USA
I gave my son my 75 L82 4 spd and it is a great eng. get rid of the cat, add real 2.5 exhaust, tune it and get a better carb and it runs great.
It has steel crank, windage tray,pink rods, forges pistons, 202/160's guide plates, 8" balancer, HEI dist, all good stuff to run or build up.
It has steel crank, windage tray,pink rods, forges pistons, 202/160's guide plates, 8" balancer, HEI dist, all good stuff to run or build up.
Instructor
Joined: Sep 2005
Posts: 194
Likes: 0
From: Hamilton Ontario
I gave my son my 75 L82 4 spd and it is a great eng. get rid of the cat, add real 2.5 exhaust, tune it and get a better carb and it runs great.
It has steel crank, windage tray,pink rods, forges pistons, 202/160's guide plates, 8" balancer, HEI dist, all good stuff to run or build up.
It has steel crank, windage tray,pink rods, forges pistons, 202/160's guide plates, 8" balancer, HEI dist, all good stuff to run or build up.
A great bulletproof engine that can be improved upon easily when the desire strikes.
Drifting
Joined: Apr 2002
Posts: 1,716
Likes: 4
From: New Baden Illinois
The aforementioned insurance rates and the federal emission requirements started to take its toll on the performance of the Corvette. After these things took their toll, Chevrolet started investing more of the Corvette budget on making the car a cruiser that people would be proud to take to the country club rather than the race track.
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Racer
Joined: Oct 2005
Posts: 343
Likes: 0
From: Rye TX
I had a 75 L48. I did a body off on it. Now I have an 80 L82. My wife and I did a near full restoration on it. Seems the L82 has better power, and we like the interior room with the two seat set-up better. The motor & tranny specs say the L82 is the better vehicle to have. We've "de-smoged" this vehicle and it seems to idle better, and the giddy-up-and-go is better.(hows that for old terms). It's never been on a dyno. This machine sat for twenty years before we bought it. Luckily, the rust is at a minimum, and was easily brought under control. IT WILL LIVE AGAIN IN THE SUMMER! Good Luck with your L82
Melting Slicks
Joined: Mar 2005
Posts: 2,838
Likes: 10
From: Austin TX
Don't forget that starting in 1972, HP ratings were figured at "net HP" instead of "gross". For instance, from 71 to 72, the engines were basically the same, yet the LT-1 in 71 was rated at 330 HP vs. 255 in 72. The LS-5 was rated at 365 HP in 72 vs. 270 in 73. That's about a 25% reduction in how HP ratings were measured.
So if you're comparing your 205 HP to a 60's car it would rate about 275 HP using the "gross" rating of the 60's.
So if you're comparing your 205 HP to a 60's car it would rate about 275 HP using the "gross" rating of the 60's.
Racer
Joined: Oct 2005
Posts: 343
Likes: 0
From: Rye TX
Don't forget that starting in 1972, HP ratings were figured at "net HP" instead of "gross". For instance, from 71 to 72, the engines were basically the same, yet the LT-1 in 71 was rated at 330 HP vs. 255 in 72. The LS-5 was rated at 365 HP in 72 vs. 270 in 73. That's about a 25% reduction in how HP ratings were measured.
So if you're comparing your 205 HP to a 60's car it would rate about 275 HP using the "gross" rating of the 60's.
So if you're comparing your 205 HP to a 60's car it would rate about 275 HP using the "gross" rating of the 60's.
Drifting
Joined: Apr 2002
Posts: 1,716
Likes: 4
From: New Baden Illinois
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
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I know of a Forum member with an all original L-82 in his car complete. It runs and drives OK. He is pulling it out to install a bigblock. If anyone is interested..you could get the whole deal from him. Shoot a note to "Gumbo"..he's in Baton Rouge. I'd probably rebuild it..but as mentioned...it comes with a lot of good parts already.
JIM
JIM
Melting Slicks
Joined: Aug 2003
Posts: 2,135
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From: Dayton Oh
I know of a Forum member with an all original L-82 in his car complete. It runs and drives OK. He is pulling it out to install a bigblock. If anyone is interested..you could get the whole deal from him. Shoot a note to "Gumbo"..he's in Baton Rouge. I'd probably rebuild it..but as mentioned...it comes with a lot of good parts already.
JIM
JIM
Le Mans Master
Joined: Jul 2005
Posts: 5,752
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From: Austin Texas
The block, pistons, cam, crank, heads, intake, balancer, carburetor, added windage tray, compression ratio and torque converter (if auto trans) are different. Other than that, they are the same.
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
2020 Corvette of the Year (performance mods)
C2 of Year Winner (performance mods) 2019
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The block isn't anything special really...but they do have a steel crank, forged pistons, good rods, 2.02 valves, a decent street cam etc.
Years ago, it was very common...I did quite a few for people....to take the almost new motor apart, hone cylinders and drop in 11.0 compression forged pistons. That got you up in the 10.0-10.5 range and if you added some cam..they really ran decent. Even the cam in them wasn't too bad....we would advance it a little.......
Anyway, they are good starting point for a buildup. Do a quick rebuild on it...a little porting etc and you can have a strong 350 for low $$.
JIM
Years ago, it was very common...I did quite a few for people....to take the almost new motor apart, hone cylinders and drop in 11.0 compression forged pistons. That got you up in the 10.0-10.5 range and if you added some cam..they really ran decent. Even the cam in them wasn't too bad....we would advance it a little.......
Anyway, they are good starting point for a buildup. Do a quick rebuild on it...a little porting etc and you can have a strong 350 for low $$.
JIM