L-82 identify? and a carb question.

[sonny74]

hey guys, i just recently puchased an orange 74 t-top coupe with 92k, a/c, t-tops, t/t, at, pw and delux interior.. i was wondering how dose one identify whether it's an L48 or L82? the badge on the console denotes the compression ratio and 290 ( i believe or maybe it's 280) lb ft of torque.. not sure of the tach redline either, i'd have to run outside and look..

secondly, i was wondering if an edelbrock AFB carb will fit under my stock hood with a low profile cleaner?

thanks in advance for any and all input..!

 

[ruby76]

Don't know about the carb question, but http://corvetteactioncenter.com/specs/1974/74id.html is a link that shows you how to decode the VIN number, I think it is the 5th character in the VIN.

 

[sonny74]

thanks for the link ruby76.. it appears i have the low power L48..

looks like i'll be swapping in either a nice 355 (approx 349hp) i have or a 69 327/300hp

 

[79-L-82]

Another source

Go to L-82.com.

They have lots of information about it.

 

[pgtr]

thanks for the link ruby76.. it appears i have the low power L48..

looks like i'll be swapping in either a nice 355 (approx 349hp) i have or a 69 327/300hp

Your L48 is a good engine and can be built up... you can do many similar upgrades to it like the L82 including different pistons (raise CR) a cam and have the heads/valves reworked sized and maybe add pushrod guides along /w studs. More expensive would be the L82s, peened rods, forged crank and 4 bolt main but depending on the mods may not be necessary. There's plenty more one can do beyond following the stock L82 formula.

I'm curious, what kind of performance improvement are you looking for from a '69 327/300 over a '74 L48?


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Thanks for the L-82.com link

 

[Vettehead Mikey]

secondly, i was wondering if an edelbrock AFB carb will fit under my stock hood with a low profile cleaner?

Why bother? It won't make more power then the stock Q jet.

 

[Chiller]

Just to put my 2 cents in. My dad said that he was getting 420 hp out of a 327 back in 1972. So I guess there is potantial in a 327. Thanks, Chiller

Your L48 is a good engine and can be built up... you can do many similar upgrades to it like the L82 including different pistons (raise CR) a cam and have the heads/valves reworked sized and maybe add pushrod guides along /w studs. More expensive would be the L82s, peened rods, forged crank and 4 bolt main but depending on the mods may not be necessary. There's plenty more one can do beyond following the stock L82 formula.

I'm curious, what kind of performance improvement are you looking for from a '69 327/300 over a '74 L48?


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Thanks for the L-82.com link

 

[pgtr]

Just to put my 2 cents in. My dad said that he was getting 420 hp out of a 327 back in 1972. So I guess there is potantial in a 327. Thanks, Chiller

There's potential in just about any SB. Did he dyno it back in '72 and was it calculated the way they measured pre '72 motors as in SAE Gross?

Anyway I thought we were talking about a 1969 327/300 (not a built up 327/420) which IIRC runs the same/simlar cam as the later '73 L48 (why I asked the question).

And the funny thing is that I don't even remember the 327 was still around much in production by '69. I thought the proverbial mid-performance '300hp' SB by '69 was, yep, you guessed it, the '69 L48 350.

 

[Chiller]

pgtr, The point that I'm making is that they're both good engines to build on. The 327 at one time came from the factory with 365 hp. From my understanding sonny74 has both engines on hand to choose from. He could drive his vette while builds the engine of his choosing. Isn't building an engine what you where talking about in the quote.

Your L48 is a good engine and can be built up... you can do many similar upgrades to it like the L82 including different pistons (raise CR) a cam and have the heads/valves reworked sized and maybe add pushrod guides along /w studs. More expensive would be the L82s, peened rods, forged crank and 4 bolt main but depending on the mods may not be necessary. There's plenty more one can do beyond following the stock L82 formula.

I'm curious, what kind of performance improvement are you looking for from a '69 327/300 over a '74 L48?


---

Thanks for the L-82.com link

 

[pgtr]

The 327 at one time came from the factory with 365 hp. From my understanding sonny74 has both engines on hand to choose from. He could drive his vette while builds the engine of his choosing. Isn't building an engine what you where talking about in the quote.

Yep! Maybe he's got TOO many options! ;-)

 

[sonny74]

yep, chiller hit the nail on the head.. i have a 350 + .030, with steel crank, GM perf. rods, forged pistons, and a comp cams 270magnum (i believe, i'd have to look at the card to be sure) i had the combination run throguh desktop dyno and it came back around 350 horse.

to answer your question pgtr, i'd expect about 110 ponies difference in performance..
the 327 is out of a camaro i believe, maybe a chevelle.. i ran the code from the front and it came back camaro or passenger car .. but that information too may be flawed.. it came from the book " chevrolet by the numbers"

aside from that, the 327 was in a 68 el camino.. it needs rebuilt.. so, i'm gonna throw the 355 in and use the edelbrock RPM performer intake and performer 750 carb thats sitting on it..

which brings me back to my original ?.. will i have hood clearance problems with this combo? i am aware that i won't be gaining significant power from just the carb, but it looks nicer than the q-jet currently on the ol' L48.. besides this motor carb/ combo has already been tuned and runs great!!

thanks for the input fellas.. take care.

 

[pgtr]

to answer your question pgtr, i'd expect about 110 ponies difference in performance..
the 327 is out of a camaro i believe, maybe a chevelle.. i ran the code from the front and it came back camaro or passenger car .. but that information too may be flawed.. it came from the book " chevrolet by the numbers"

aside from that, the 327 was in a 68 el camino.. it needs rebuilt..

Don't know if it's my memory or the data that's flawed? Like 69 I'm not familiar w/ a 68 327/300 in Camaros either. Camaros came w/ optional 350s in both '68 and '69 as I believe did Chevelles. And Camaros while they had 327s in '67 it it wasn't rated at 300hp. <shrug> Corvettes did have the L75 327/300 throughout most of the C2 era till '68 or so. If it's a genuine Corvette engine it may be of good value to someone and that change could easily be put to building up your original L48 or the 355 or whatever... just a thought.

110 hp difference between a 'generic?' 327/300 and a '73 L-48 350/190? I think that would be an overly optimistic expectation on the difference in HP between the two. I'd guestimate it closer to ~30hp or so give or take.

 

[MoeJr]

68 Camaros were available with a 327/275hp motor. I got a customer who own a 68 Conv with this engine in it.Numbers match

 

[sonny74]

yeah, i obviously missed your statement refering to the SAE rating system of the 60's-70's whatever.. you apparently know more about these engines than i do..

either way, the L48 is a dog IMO.. i've had my 355 in my 70 camaro ss and it'll flat get with it.. for what it is.. my 74 L48 on the other hand, will barely burn the tires..

for me it's a no brainer.. pull that weak motor and put the 355 in, for now..

i think i'll check the #'s on that 327 and post em up, maybe one of you guys can/would help me identify what it is and/or came out of..? i'm pretty sure a 250hp 327 was available in 69 camaro's, but again, not 100% certain..

anyhoo, thanks for the input fellas.. i'll post up some numbers and codes tomorrow..

 

[pgtr]

MoeJr, IIRC the 68 chassis service manual didn't show a 327/275 for the Camaro - but again my memory may be in error and I don't have one any more. There was a 327/275 option in '67 for Camaros however. The '68 Camaro we had here once had as I recall an original 350. Seems strange they'd offer both 327s and 350s in the same year for the same model of car. Could it possibly have been a particularly early '68 Camaro?

Sonny74, actually those aren't my references - that's the way Chevrolet and all makers rated HP before '72 vs later. That's why I asked why you were considering a generic 327/300 as a viable performance option to an L48 - I'd hate to see anyone go thru the effort to install a 327/300 and not realize the expected actual 110hp difference. Again, as far as I know there were no 327s in Camaros after 67, beit 250hp or 300hp or 275hp. In '69 there was a 350/300 and a 350/250. Care to guess what the RPO code was for the 350/300 in '69 was for Camaros? Yep, L48. Your '73 L48 is essentially the same engine. It's HP is rated much lower due mostly to a different method for calculating it. It is also slightly reduced to account for lower octane gas (CR) but it should also have hardened valve seats for unleaded. In fact I believe they all run the same cam.

 

[sonny74]

hey pgtr, i realized what you were saying after i'd made the aforementioned comment, thanks for clarifying..

i have a friend who is into nothing but camaros, buys sells restores, he is my sole source for information on the blah, blah of the 327's in 69.. like i said though, i'm far from an authority on camaros.. i just own a 70 SS, NOM and he and i talk from time to time about things bowtie related in general...

thanks for the useful info.. i'm off to get the #'s and codes from my mystery engine..

talk to ya later, take care.

BTW, i do plan to transplant my L48 for the +.030 350.. builder claimed it to be 10.5:1 CR, desktop dynoed at 349hp/385ft lbs. with the 270H comp cams grind.. that was also ran with stock exhaust and stock intake. not sure what kinda gain to expect from the RPM performer and 750 performer carb along with Allen's side exhaust.?

 

[sonny74]

my other resource for bowtie and/or camaro info are the following sites: Mortec.com, and nastyz28.com..

both sites have full lists of casting numbers along with their corresponding suffix codes, etc..

the casting # on this mystery block is 3932386 next to the casting # next to the idiot oil sending unit is the lone # 5 with a square casting mark with 2 lines running through.

it's either a 69 302 4 bolt Z-28 290 hp
69 327 2 bolt 210 or 235 hp
69 350 4 bolt 300 or 350 hp

these are the 3 applications this block was used for..

scratch the Z as the suffix isn't DZ
in fact the only suffix that fits is the 69 2 bolt 235 hp 2bbl 327 used in F and B bodies, BTW the suffix is FC.
the other 4 letters stamped on the pad front passenger side are K11 25 FC.
it also appears to have a VIN or partial VIN 19V138115

that pretty much narrows it down.. i could pull the valve covers and get the head casting #'s but i believe the engine suffix code tells the tale.. it appears to be a 69, 327, 235 hp, 2 bbl.. not withstanding the decoding of the K11 25..

do you know what these may mean or have any resource i may be able to find out?
if not i'll pull a valve cover tomorrow, just out of curiousity..

agian, thanks for any and all input pgtr..
talk to ya later, take care..



BTW.. i still haven't gotten an answer to my original question (well actuall, one of the 2 original questions) will aaaaaan Edelbrock performer RPM intake with an Edelbrock performer carb fit under the stock hood with a low profile air cleaner..????!?!

 

[JohnZ]

It's a large-journal block, cast and assembled at McKinnon industries in Canada, and the VIN derivative (if the "V" is correct) says it was originally installed in a Chevy truck built at the GM Truck & Coach assembly plant in Pontiac, Michigan.

 

[sonny74]

hello JohnZ, thanks alot for ending the "mystery" to some degree, i, however, have another question..

i believe i was once told that all 327's are small journal, is this true? if so, then it must make my engine a 350 truck from a 69? also, may i ask what references you use to decode the casting #'s, etc.?

well, this motor did come out of a 69 El Camino, i suppose it's possible it was the original motor since it seems to have come froma truck...

anywho, enough about my junk $100 motor that i didn't know jack about...

you all take care ... and enjoy those cars!

 

[JohnZ]

'69 327's had large journals, and shared the same block as the 350's. I use a 30-year collection of references .