What makes a L82 weigh more than Base engine?

[Robert R.]

While doing some research on 1973s, the AMA Spec sheet notes that there is a +42 lbs. to the overall car weight when the L82 is ordered. Looking at the NCRS Spec Guide, the block and intake are the same, but the heads are different when comparing the two engines. Does the added weight come from the heads and other internal parts on this engine (crank, pistons, etc.)? ... Thanks in advance for your reply(s). Bob

[William C.]

Re: What makes a L82 weigh more than Base engine?

I'd be more inclined to look at other changes to the car, suspension, or exhaust system as the engines themselves are essentially the same, including as I recall the actual head castings.

[Warren F.]

Re: What makes a L82 weigh more than Base engine?

I believe part of the weight difference is definitely due to the aluminum intake manifold on the L82 option versus the cast iron intake on the L48 engine.

[Mike F.]

Re: What makes a L82 weigh more than Base engine?

Just a guess on one of the items, bigger radiator - more coolant, and all that extra horsepower!

[Robert R.]

Re: What makes a L82 weigh more than Base engine?

Unless new information has surfaced, per the NCRS Corvette Spec Guide, both base and L82 use a cast iron intake. And I wouldn't think that an aluminum intake would weigh more than the cast iron intake. They both also use the same exhaust manifolds. As to suspension, and drive train, would the L82 use the same half shafts as the big block engine? The AMA sheet does list the LS4 454 option at a +211 lbs., which would make sense in regards to suspension and engine weight for that option weight increase.

[Steven B.]

Re: What makes a L82 weigh more than Base engine?

Forged vs cast crank and larger valves do not equal forty two pounds. TH four hundred on optional engine and three-fifty on base. I do not know the weight differences and four speeds should be same for both engines.

[Michael W.]

Re: What makes a L82 weigh more than Base engine?

As to suspension, and drive train, would the L82 use the same half shafts as the big block engine?

All three engine options used the same half shafts, BB engine were shot peened.

No idea where the weight difference comes from (?)

[Robert R.]

Re: What makes a L82 weigh more than Base engine?

Hi Steve, From what the options weights sheet states, it looks like the 4spd is considered to be the minimum to the base car weight. THM 400 is the only trans listed at +54 lbs.; (THM 350s started in 1976). And if AC is ordered, three different weights listed: +95 for 4spd and 350 ci, +80 for THM and 350 ci, and +90 for 454 and either trans (that doesn't make sense either).

[Robert R.]

Re: What makes a L82 weigh more than Base engine?

..as from an earlier post, maybe the extra 55 horses are the reason for the extra weight, heh...

[Michael G.]

Re: What makes a L82 weigh more than Base engine?

If it's not the extra horses then it must be the hood badges!!!!!!

[Harmon C.]

Re: What makes a L82 weigh more than Base engine?

I think L-82's has a stabilizer shaft on the rear that an L-48 will not have. Brackets and all parts may be 42 pounds.

[Robert R.]

Re: What makes a L82 weigh more than Base engine?

Ok, that may account for some of it. Would the L82 also have heavier springs on the front, not for extra engine weight, but for a stiffer suspension?

[Steven B.]

Re: What makes a L82 weigh more than Base engine?

Optional L-82 and base L-48 had base suspension standard with FE-7 (Gymkhana) suspension optional.

[Harmon C.]

Re: What makes a L82 weigh more than Base engine?

The rear sway bar was standard on L-82 and 454 without FE-7.