L82 Torque
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Race Director
Joined: Apr 1999
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From: NM
L82 Torque
Was just reviewing my '73 page and noticed something I had never seen before. The 73 L82's troque was 285@4000rpm. I then looked at the base L48. Its torque was 270@2800rpm. So the L82 have 15 lbs/ft of torque but at 1200 more rpm. Looks like that cam really moved the power up tach.
It really is susprising the difference in rpm at which the engines made their torque. I did not realise that the L82 cam was that far out. For compairsum, the 72 LT1's torque was 280@4000rpm. Looks like the L82 cam was about as wild as the LT1's solid cam.
tom...
It really is susprising the difference in rpm at which the engines made their torque. I did not realise that the L82 cam was that far out. For compairsum, the 72 LT1's torque was 280@4000rpm. Looks like the L82 cam was about as wild as the LT1's solid cam.
tom...
Thread Starter
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Joined: Apr 1999
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From: NM
Re: L82 Torque (johnnyc)
I think the L-82 cam was the same grind as the earlier L-46 350 HP motor.
tom...
Le Mans Master
Joined: Feb 1999
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From: Tampa Bay FL
Re: L82 Torque (Tom73)
I would have liked to have been able to see the potential of the L48 or L82 cam demonstrated on a dyno with improved heads, headers, intake, carb, and exhaust. Unfortunately, the cam is one of the first parts 'tossed' in the quest for more power.
Would like to know how the L82 cam compares to the 268H (Comp High Energy) or 262X (Xtreme Energy cams) that are available today; assuming all of the other go fast goodies are installed in both scenarios.
I wouldn't be surprised to discover the L82 cam offers good performance potential; and from a 30+ year old cam grind.
Would like to know how the L82 cam compares to the 268H (Comp High Energy) or 262X (Xtreme Energy cams) that are available today; assuming all of the other go fast goodies are installed in both scenarios.
I wouldn't be surprised to discover the L82 cam offers good performance potential; and from a 30+ year old cam grind.
Burning Brakes
Joined: Jul 2001
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From: Ajax Ontario
Re: L82 Torque (FERL 73)
I believe the L46/L82 cam is similar (not exactly same) as the L79 cam (350hp 327, also known as the "151" cam). The L79 engine vs base 300hp makes the same 360 ft lbs of torque at 3800 rpm, whereas base hits this at 3600, just 200 rpm lower. My 327 with the XE262 did 267 ft lbs rear wheel on the dyno a year ago, before fixing an oil burning problem (seals) and before setting total timing and carb up properly. Seat of pants is car is well above that reading now, maybe another 20-25 more? Point of this is that 267 rear wheel equates to gross of probably 400, well above the factory rating (360) with the 151 cam. I guess this particular grind is designed to maximize torque, which for a mild street car is more important than hp? Has anyone swapped the stock L82 cam out for one of the aftermarket cams and have dyno results both ways? It is an interesting question! :cheers:
Race Director
Joined: Aug 1999
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From: Toronto
Re: L82 Torque (FERL 73)
L82 was .10 quicker and 2.5 mph faster in the 1/4 than the L48. Looks like the real advantage to the L48 was a little better bottom end for mods.
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Le Mans Master
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From: San Diego CA
Re: L82 Torque (jvm)
Supose Bubba or his brother put headers, cut the cat and installed true duals and put a Edlbrock intake on his L82. What horse power would these changes make?
Unfortunatly I dont have a dyno baseline to start from - I suppose I could find a local Dyno after the stuff is installed to get an after.
Thread Starter
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Joined: Apr 1999
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From: NM
Re: L82 Torque (jvm)
Supose Bubba or his brother put headers, cut the cat and installed true duals and put a Edlbrock intake on his L82. What horse power would these changes make?
tom...
[Modified by Tom73, 4:02 PM 6/6/2002]
Pro
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From: IL
Re: L82 Torque (SuperFast80)
quote:
--------------------------------------------------------------------------------
L82 was .10 quicker and 2.5 mph faster in the 1/4 than the L48. Looks like the real advantage to the L48 was a little better bottom end for mods.
I respecfully disagree. The L-82s were at least .5 secs faster to 60 and 1 sec/5mph faster through the 1/4. Articles on my archive site will bear this out.
--------------------------------------------------------------------------------
Sorry Superfast. I must have read it incorrectly. I took my information from your site. I guess I looked at the wrong artice.
1973 L-48, L-82 and LS-4 Road Tests; High Performance Cars, September 1973 page 4
By the way, 73spot & superfast your sites are great and the info is greatly appreciated. (even if I read it wrong)
[Modified by FERL 73, 5:01 PM 6/6/2002]
Race Director
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From: San Jose CA
Re: L82 Torque (fauxrs)
A good source to see how the stock cams do is the GM GW350 buildup done in Chevy High Performance. http://personal.clt.bellsouth.net/cl.../chp/gm350.htm
The LM-1 has the same cam as an L-48. With headers, dual exhaust and a performer intake, the engine does 265 hp/350lb-ft. With the heads ported, 280 hp and 361 lb-ft.
A change in cam at that point added 56 hp!!! and 17 lb-ft. (Going from the L-48 cam to the XE268).
336 hp, 377 lb-ft. The cam is definitely a weak point in the L-48, but the L-82 is actually quite nice. It is more aggressive than the CS268H, the most aggressive smog legal cam Comp Cams puts out, *which* has slightly less lift on both exhaust and *intake* than the L-82's. The XE268 is a bit more aggressive than the L-82. With a decently ported set of heads, performer intake, headers and dual exhaust, I bet the L-82 would put out about 315 hp. I wouldn't be surprised to see it do even more with a good set of heads.
-Steve
[Modified by Pacin'California, 9:10 PM 6/6/2002]
The LM-1 has the same cam as an L-48. With headers, dual exhaust and a performer intake, the engine does 265 hp/350lb-ft. With the heads ported, 280 hp and 361 lb-ft.
A change in cam at that point added 56 hp!!! and 17 lb-ft. (Going from the L-48 cam to the XE268).
336 hp, 377 lb-ft. The cam is definitely a weak point in the L-48, but the L-82 is actually quite nice. It is more aggressive than the CS268H, the most aggressive smog legal cam Comp Cams puts out, *which* has slightly less lift on both exhaust and *intake* than the L-82's. The XE268 is a bit more aggressive than the L-82. With a decently ported set of heads, performer intake, headers and dual exhaust, I bet the L-82 would put out about 315 hp. I wouldn't be surprised to see it do even more with a good set of heads.
-Steve
[Modified by Pacin'California, 9:10 PM 6/6/2002]
Instructor
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From: kennett square,pa,us
Re: L82 Torque (jvm)
Supose Bubba or his brother put headers, cut the cat and installed true duals and put a Edlbrock intake on his L82. What horse power would these changes make?
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I did it and the engine was still a DOG. The 76 cc heads and 9.0 compression hurt.
Bud
[Modified by bud snyder, 9:04 PM 6/6/2002]
--------------------------------------------------------------------------------
I did it and the engine was still a DOG. The 76 cc heads and 9.0 compression hurt.
Bud
[Modified by bud snyder, 9:04 PM 6/6/2002]
Race Director
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Re: L82 Torque (Pacin'California)
The LM-1 has the same cam as an L-48. With headers, dual exhaust and a performer intake, the engine does 265 hp/350lb-ft. With the heads ported, 280 hp and 361 lb-ft.
A change in cam at that point added 56 hp!!! and 17 lb-ft. (Going from the L-48 cam to the XE268).
336 hp, 377 lb-ft. The cam is definitely a weak point in the L-48, but the L-82 is actually quite nice. It is more aggressive than the CS268H, the most aggressive smog legal cam Comp Cams puts out, but has slightly less lift on both exhaust and duration than the L-82's. The XE268 is a bit more aggressive than the L-82. With a decently ported set of heads, performer intake, headers and dual exhaust, I bet the L-82 would put out about 315 hp. I wouldn't be surprised to see it do even more with a good set of heads.
-Steve
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Joined: Aug 1999
Posts: 10,073
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From: Toronto
Re: L82 Torque (FERL 73)
Sorry Superfast. I must have read it incorrectly. I took my information from your site. I guess I looked at the wrong artice.
1973 L-48, L-82 and LS-4 Road Tests; High Performance Cars, September 1973 page 4
By the way, 73spot & superfast your sites are great and the info is greatly appreciated. (even if I read it wrong)
1973 L-48, L-82 and LS-4 Road Tests; High Performance Cars, September 1973 page 4
By the way, 73spot & superfast your sites are great and the info is greatly appreciated. (even if I read it wrong)
Try the 1978 L-82. It had 30 hp LESS than the 1973 and it ran like this:
The 1977 L-82 had 40 hp LESS than 1973 and it ran like this:
The L-82 is a strong motor. Not like an LT-1 or an L-46 but competent enough be considered a good small block. Remember that the 1975-1980 L-82s were constricted by the worst emissions shet in history.
[Modified by SuperFast80, 10:29 AM 6/7/2002]
Safety Car
Joined: Feb 1999
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From: Fountain Hills AZ
Re: L82 Torque (68shark)
Doug, yup. The L46 was a 350 cube version of the L79 327. Those extra cubes allowed a little more cam with the same drivability. The L79's 151 was 222º @ .050, .447 lift. The L46's cam was 224º/.450 lift. Lot's of guys rave about the 151 but I like the later version better.
Race Director
Joined: Apr 1999
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From: CORVETTE 77 385 C.I. TEXAS
Re: L82 Torque (Pacin'California)
... The cam is definitely a weak point in the L-48, but the L-82 is actually quite nice. It is more aggressive than the CS268H, the most aggressive smog legal cam Comp Cams puts out, *which* has slightly less lift on both exhaust and *intake* than the L-82's. ...
-Steve
-Steve
The 268H w/ 1.52 rockers maxes out safe lift @ .460 intake & exhaust.
Some know I normally give conservative HP estimates w/o stating. This time stating properly set up conservative estimate, i.e. min. Comp Cams 268H w/ decent 2.02/1.60 heads.
335+ HP near 400 TQ i.e. 385+
:cool:
