L82 question...
Thread Starter
Instructor
Joined: May 2011
Posts: 197
Likes: 4
From: Rochester New York
L82 question...
A few of my hoodlum buddies and I were bench racing and bench wrenching down at the local watering hole today...
My question to the panel is, once and for all: Can a 78, Silver Anniversary L82 be a two bolt main? I say 'yes' as long as it has 10 to 1 compression and a forged crank... Lets have it!
My question to the panel is, once and for all: Can a 78, Silver Anniversary L82 be a two bolt main? I say 'yes' as long as it has 10 to 1 compression and a forged crank... Lets have it!
Last edited by ThePabst; May 10, 2015 at 07:21 PM.
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As far as I know, all L-82s are 4 bolt main. 
Thread Starter
Instructor
Joined: May 2011
Posts: 197
Likes: 4
From: Rochester New York
Here is where this thread really starts... My father gave me his 78 SA. It was his pride and joy for years.
He bought it from a 'reputable' dealer near New Port Riche, FLA. I have the original independent parasail saying that this is indeed an original car and it was sold to him as adverti$$$ed.
I have been real busy getting this rig back into shape. In my travels under the hood, I found this motor has a two bolt main.
I am going to "flame" this inspector by name and business on ALL outlets, as well as the selling dealer if they ripped my father off. Its important that I am right.
If these guys are sum-bags I want to make sure they and everyone else knows it.
He bought it from a 'reputable' dealer near New Port Riche, FLA. I have the original independent parasail saying that this is indeed an original car and it was sold to him as adverti$$$ed.
I have been real busy getting this rig back into shape. In my travels under the hood, I found this motor has a two bolt main.
I am going to "flame" this inspector by name and business on ALL outlets, as well as the selling dealer if they ripped my father off. Its important that I am right.
If these guys are sum-bags I want to make sure they and everyone else knows it.
Last edited by ThePabst; May 10, 2015 at 08:33 PM.
Drifting
Joined: Oct 2005
Posts: 1,615
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From: Forth Worth TX
Does the VIN indicate an L82 engine was originally installed? (The fifth digit in the VIN should be a "4" if it was delivered with an L82.)
Does the VIN and Engine Stamp Pad match?
Where does the tach redline at?
Last time I checked a 78 L82 only has 9:1 c/r.
http://www.corvsport.com/Corvette/C3..._1978_VIN.html
If you open this link and go to page 43 of the .pdf, look under Engine-Crankshaft, you'll see a line that reads "No bolts/main brg. cap" and the number "2" for both L48 & L82.
https://www.gmheritagecenter.com/doc...t-Corvette.pdf
Does the VIN and Engine Stamp Pad match?
Where does the tach redline at?
Last time I checked a 78 L82 only has 9:1 c/r.
http://www.corvsport.com/Corvette/C3..._1978_VIN.html
If you open this link and go to page 43 of the .pdf, look under Engine-Crankshaft, you'll see a line that reads "No bolts/main brg. cap" and the number "2" for both L48 & L82.
https://www.gmheritagecenter.com/doc...t-Corvette.pdf
Last edited by Revi; May 10, 2015 at 08:57 PM.
Melting Slicks
Joined: Sep 2004
Posts: 3,223
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From: Northeast
Out of curiosity what does the engine stamp pad show. Suffix for a 78 L82 4spd is CMR. CMS for an automatic. Does it also show your partial vin?
Tach red line:
L48 & L82 w/ac the same
L82 wo/ac was higher
Tach red line:
L48 & L82 w/ac the same
L82 wo/ac was higher
Last edited by BKarol; May 10, 2015 at 08:46 PM.
Burning Brakes
Joined: Sep 2005
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From: B'ham Alabama
All L-82's were 3 bolt mains. You can tell if the car is a factory original L-82 by the VIN number. You can tell if it has it's original engine by the engine ID number, (should match the cars VIN#).
Of course, the engine number can be restamped.
But I'm positive....ALL L-82's were 4 bolt mains.
Of course, the engine number can be restamped.
But I'm positive....ALL L-82's were 4 bolt mains.
Safety Car
Joined: Jun 2004
Posts: 4,364
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From: Beecher Illinois
Doing a little research into your earlier posts, going way back to May 2011, you state this 78SA is an L48.
Why do you now think it's an L82?
Seems most folks that are unsure if they have the L82........don't.
I got way too much time on my hands
Why do you now think it's an L82?
Seems most folks that are unsure if they have the L82........don't.
I got way too much time on my hands
Last edited by KapsSA; May 10, 2015 at 11:47 PM.
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This is getting interesting now.
Burning Brakes
Joined: Sep 2005
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From: B'ham Alabama
All L-82's were 3 bolt mains. You can tell if the car is a factory original L-82 by the VIN number. You can tell if it has it's original engine by the engine ID number, (should match the cars VIN#).
Of course, the engine number can be restamped.
But I'm positive....ALL L-82's were 4 bolt mains.
Of course, the engine number can be restamped.
But I'm positive....ALL L-82's were 4 bolt mains.
Team Owner
Joined: Jun 2000
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From: Southbound
Cruise-In II Veteran
It's likely to be a base engine L-48 with an L code in the VIN. I'd be wary of flaming anyone based on second hand information. Unless you were present at the time your father made the deal on the car, you don't honestly know who said what to whom about what.
Last edited by Easy Mike; May 11, 2015 at 07:16 AM.
Thread Starter
Instructor
Joined: May 2011
Posts: 197
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From: Rochester New York
Yes I did start an earlier post as this has been an on-going question.
That older post ended up being about 50/50 yes or no. It was confusing at best, so was time spent bumping around the net.
The car has L82 badges and the 5th digit of the VIN is a 4. The red line is 5500.
Exactly what am I looking for on the engine block?
~The WRITTEN appraisal by an 'expert' hired at the time of sale calls it authentic. I have this document. What chaps my *** is that based on this appraisal, my father paid top dollar.... Top buck for a leaking, overheating, dolled up wreck with leaking shocks, butchered wiring harness, a beat frontend and a whipped cam. This dealer and his appraiser are now working under different names. I know it's always buyer beware, I get that, but if they are predators they need to be pointed out.
My dad passed the car onto me as his health is poor. It is now in very good daily driver condition. But it has taken many thousands of dollars and two full winters. It makes me angry that people out there would do this to old men with stars in their eyes. ~
Last edited by ThePabst; May 11, 2015 at 08:03 AM.
Melting Slicks
Joined: Sep 2004
Posts: 3,223
Likes: 666
From: Northeast
"Exactly what am I looking for on the engine block?"
In the front of the block below the valve cover on the passenger side you will see a somewhat square block. If it is covered in grease or oil use a rag and cleaner to read the numbers. No abrasive.
Top line gives the build date and suffix. Below that is stamped a partial vin which hopefully will be yours. In this case CMR is for a L82 4spd:
In the front of the block below the valve cover on the passenger side you will see a somewhat square block. If it is covered in grease or oil use a rag and cleaner to read the numbers. No abrasive.
Top line gives the build date and suffix. Below that is stamped a partial vin which hopefully will be yours. In this case CMR is for a L82 4spd:
Le Mans Master
Joined: Apr 2008
Posts: 9,425
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From: Powassan ON
Alpha numeric codes stamped into the block. Look near the front of the drivers side (?) valve cover. A flat area cast into the block. May or may not be a painted surface. Should have the last few numbers of the ORIGINAL vehicles VIN stamped in it along with some alpha codes in larger capital letters. Pad codes may be gone if the engine has be milled (decked).
Post pics.
Tach say L82 on the bottom of the face?
dodosmike
BAHHHH. lol. Karol's pic shows it better than I described it.
Post pics.
Tach say L82 on the bottom of the face?
dodosmike
BAHHHH. lol. Karol's pic shows it better than I described it.
Last edited by Dodosmike; May 11, 2015 at 09:42 AM.
Thread Starter
Instructor
Joined: May 2011
Posts: 197
Likes: 4
From: Rochester New York
"Exactly what am I looking for on the engine block?"
In the front of the block below the valve cover on the passenger side you will see a somewhat square block. If it is covered in grease or oil use a rag and cleaner to read the numbers. No abrasive.
Top line gives the build date and suffix. Below that is stamped a partial vin which hopefully will be yours. In this case CMR is for a L82 4spd:
In the front of the block below the valve cover on the passenger side you will see a somewhat square block. If it is covered in grease or oil use a rag and cleaner to read the numbers. No abrasive.
Top line gives the build date and suffix. Below that is stamped a partial vin which hopefully will be yours. In this case CMR is for a L82 4spd:
Safety Car
Joined: Aug 2000
Posts: 3,711
Likes: 43
From: San Antonio TX
You can't tell what's inside the crankcase by making observations around the engine bay. By what method did you use to make this determination? The only way to know anything for double-sure is to drop the oil pan or at least pull the front timing chain cover and run an inspection camera into the crank case. You aren't by chance coming to this conclusion by why you might have seen with the timing cover off and looking at the number One main cap, are you? That cap is a two-bolt for all smallblocks.
Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
A few of my hoodlum buddies and I were bench racing and bench wrenching down at the local watering hole today...
My question to the panel is, once and for all: Can a 78, Silver Anniversary L82 be a two bolt main? I say 'yes' as long as it has 10 to 1 compression and a forged crank... Lets have it!
My question to the panel is, once and for all: Can a 78, Silver Anniversary L82 be a two bolt main? I say 'yes' as long as it has 10 to 1 compression and a forged crank... Lets have it!
Where is your guarantee coming from?
Thread Starter
Instructor
Joined: May 2011
Posts: 197
Likes: 4
From: Rochester New York
Where does your criteria of 10:1 compression and forged crank come in to play as a requirement for a motor with two bolt main bearing caps?
Do you have a picture? I mean this in the least condescending way as possible, but no motor has a single "two bolt main," you typically have three main bearing caps in your 350 that are drilled and tapped to add the extra bolts to each be 4-bolt main caps.
Where is your guarantee coming from?
Do you have a picture? I mean this in the least condescending way as possible, but no motor has a single "two bolt main," you typically have three main bearing caps in your 350 that are drilled and tapped to add the extra bolts to each be 4-bolt main caps.
Where is your guarantee coming from?
As part of a complete referb, I put a new oil pump in her last spring. When I was installing the oil pump I noticed the rear main cap only had two bolts.
That is what sparked my curiosity. It wasn't even the engine designation per se, it was my recollection that most heavy duty GM anything, back then that shipped with a manual used a four bolt, the two bolts were usually used for Automatics. I thought that this may have had a trans swap. That's when I started to stew about the appraisal.
Those were dark days for GM back then, I wonder if a few stinkers snuck through...
Last edited by ThePabst; May 11, 2015 at 11:49 AM.