SMS 1

New here and thought I'd ask . . .

I dont have the orig spid label from this car and haven't really run the #'s but have been told that this car came with a seemingly rare list of options. Here is what I got . . .

1984 Z28 5.0 4bbl HO M5 Hardtop
Vin G
3.73posi rear disc (numbers do match car)
Power Everything (excepr seats)
Large Sway bars
3" exhaust (aftermarket maybe? No aftermarket markings ie: Dynomax ect.)
No AC
Aluminum Radiaitor/Elec Fan
No cruise or Tilt however

I know there is more that I am forgetting here but I'll add it as I remember. Just curious if anyone had any clue as to approx how many cars had these options in 84. Thanks-

SMS 1

OK after reading a couple of other posts here maybe I need to re-check those rear-end #s again. Were the Z28s even offered from GM with a posi rear disc option in 84? Or is it a Dana swap?

FormerL69

iTrader: (2)

HO cars came with the 3.73 rear and had posi. Not sure about the ability to order the car with the options you stated, but the 3" exhaust doesn't sound right ro me.

LAFireboyd

iTrader: (3)

The car sounds like a normal L69(HO) car, which first appeared in 1983. It came with the electric fan, 3.73 gears(no posi in '83, but posi in '84), and the stock exhaust system used a 3" cat with a 2 3/4" I-pipe to the muffler.

So if your I-pipe is 3", then it's aftermarket. You could measure the circumference by wrapping a string around the pipe and dividing that by pi(3.14) to get the diameter(circumference = pi x dia). A 2 3/4" pipe would measure about 8 5/8" around. A 3" pipe would measure about 9 7/16" around. That's easier and more accurate than trying to "eyeball" it with a ruler.

OSU76LT

What do you mean "no posi in '83"?
All technical info I've ever seen has listed posi as mandatory with 4-wheel disc brakes in 1983.

LAFireboyd

iTrader: (3)

That info might be trying to cover the L69 years, in general, but nope, no posi was available for it in 1983. But it did come with the 3.73 gears.

Edit: a posi and 4-wheel discs was available for the other engines in 1983, but not with the L69.

SMS 1

Hmmm, cool stuff. It's just really too bad the car is in such poor shape and has become my parts mule. Just curious as to what I was driving, always seemed to have some wierd things I hadn't seen before on such an early year.

Randy82WS7

the L69 pipe was oval shaped not round exactly, was a name for it like wide mouth related kind of name

forgot..

electric fan is L69 stuff, normal
3.73 is normal in an 84 Z28 L69 too, ive had one already identical 84 z28 L69 700r4 3.73

common

aluminum 5 star mags, gold colored,
car was dark gold brown almost, but technically was gold metallic
by the paint code

billions of them built, it was a van nuys built 84 Z that i had

no tilt, did have a/c but not connected, had T tops, tach setup, but had copper radiator insead of aluminum, and it ran 190or more all the time, and the car was just plan badass it hooked and went, whenever you wanted it to, it had no lag time connecting and moving off, at all,.

was rusted out in alot of places, not really fixable, wont really ever be worth too much, was on its second 305 engine, and now its in indiana i sold it for 900, gave 1300 when i got it, i paid way too much for it though, was fun though.


my 84 didnt have G80 posi RPO though,
but it never did anything but grab and go so it never laid rubber it just leaped and went everytime, so i dunno for sure other than by lack of posi code, and was inside the axle when i first got the car cuz i had to pull the shafts and replace backing plates and drums and all with new ones that were on an 81 cutlass supreme i had out here, they were worn bent up junk shape on the Z, i didnt notice any springs or clutch discs in the carrier but then i didnt really look into the unit, i just rmeoved the axle lock pin bolt and went from there, it snapped off on me i had to get that sucker out of there it was no fun, stupid lock bolts.,,, they snap off very easily.,!



good luck

SMS 1

Sounds cool. I never had the experience of the orignal 305HO in mine. When I purchased the car 8 years ago it had two rods dangling out of the pan, one out of the block and the entire #3 piston had crashed through the cylinder wall to take a swim in the coolant jacket! So I swapped in a 350 before ever driving a single mile. Got it for a paltry $300 though and drove the hell out of it for the first two years. The thing just always seemed a notch above what I had seen as standard on those early years. I have learned quite a bit about the L69 cars in the last few weeks and I really wish the car was salvageable, but I guess thats just how it goes. She had a very long and hard life. Overall a really good run but it's time for her to go to pasture now

RSFreak

My '84 Z28 has the L69 and 3.73s. How do I know if it is posi?

FormerL69

iTrader: (2)

If remember correctly, the 10-bolt posi units have a metal tab cast into the lower left or right side of the carrier at 4:00 or 7:00 as you look at the carrier from the rear.

I'm pretty sure it was on the right side.

The 305 HO cars were great. Mine had 100k when I got it -- which was cool, because the odo read 000000 and it was like having a new car!. A buddy of mine had an LG4 and even with mods, it just never seemed to have the grunt of my L69.

As Fast68 said, the car just leaped off the line whenever you laid into it. Too bad a lot of the 305HOs seem to get replaced with 350s, but I can understand people making the swap if the 305 was expired.

Randy82WS7

i want to know more about this metal tab on the carrier ?
on the exterior of the diff housing ? or ?

yeah 305 HO you have a hard time telling the difference from it to a 350 engine most years 70s and up,

305HO was 190 horse for alot of years including 84, thats net rating, thats damn good for a 305,

no real reason to yank a L69 out especially, unless you killed it


they are badass for a 305,. for sure, i have had a few even LG4 that were badass, i even had one in a 68 c-10 with 326 three speed manual and 3.73 12 blt all original, and it was no slow vehicle by any means, but damn it was slow with the old original (chevy not oldsmobile lol)307 2bbl(these were made 68-73) in it still before that threw the #1 into the oil pan and through it!
lost all its oil and the rest was history,


i know the 3.73 cars with 700r4 deep first gear and the 305 will move damn quick, they were not laggy cars by any means, ive had a couple of them, so i know. i miss it, and the 68 too, the 68 was faster than any car i put it against at the time, especially after the 355 and th350 shorty swap in



good luck

FormerL69

iTrader: (2)

I just checked an '85 shop manual I have. The limited slips have a tag on them. I'd swear this was cast into the diff housing, but it may have been something that was attached through one of the cover bolt holes. It's on the lower-left corner of the pumpkin.

Here's a picture from the manual:

RSFreak

Yeah, I'm loving my L69! My previous Camaro had an LO3 which was a total dog compared to this car. I'm sure I'm feeling the 3.73s as well since my RS had 2.73s! The other day I was pulling out of Pro Max and decided to have a little fun so I punched it and she chirped the tire(s?) a little and then just hooked and I was gone! Came to a stop sign and floored it into a left turn, got a little sideways, and then hooked again, straightened out, and I was flyin'! For the first time since owning a Camaro, I don't want a 350. I wanna see how far I can take this 305!

RSFreak

I couldn't see anything like that. My pumpkin is pretty rusted though. Any chance the tag fell off?

FormerL69

iTrader: (2)

Again, I can't recall if the tab was cast into the housing or not, but I'm fairly sure it was. If so, rusty or not, it certainly wouldn't just fall off. Might be that the gears in your car were changed out at some point too.

As Fast68 said earlier, the RPO code for posi was G80. If you have the trim tag for your car, check that.

Apeiron

The limited slip tag is a small piece of tin under one of the cover bolts.

RSFreak

Is it possible to have the G92 and G80 RPOs? I know I have 3.73s, but at this point not sure if its posi or not.

jmd

iTrader: (4)

Yes. G92 is an indicator of an optional rear gear ratio, so an LG4 equipped car with 3.08 rear axle would have the G92 RPO in some years. You could order posi and optional rear gear.

But, I don't think 3.73's were an optional rear gear in the L69 cars, as you couldn't order anything but 3.73's with the L69 in f-bodies.

-Matthew