2 Z51 questions
Thread Starter
Instructor
Joined: Apr 2004
Posts: 217
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From: Winnipeg MB
2 Z51 questions
Hi
1) I have a 86 Corvette and was told when I bought it that it was a Z51 from the original owner. I cant find any option codes on the car. It does have the hp rating on the console. What other ways can I tell if it is a Z51?
2) What all does the Z51 have for options over and above the stocker?
Thank you
1) I have a 86 Corvette and was told when I bought it that it was a Z51 from the original owner. I cant find any option codes on the car. It does have the hp rating on the console. What other ways can I tell if it is a Z51?
2) What all does the Z51 have for options over and above the stocker?
Thank you
Melting Slicks
Joined: Jun 2004
Posts: 3,032
Likes: 4
It's essentially a suspension package, with a few extra goodies (performance gearing, HD cooling, oil cooler, etc.)
Almost all of the options were available individually as well (My '85 is not a Z51, but has every Z51 option that I know of for my year).
If you want more info, try a search, you'll find pages of threads about it.
And if you cant find the RPO list (in the center console or rear compartment), turn the wheel lock-to-lock, it should be about 2 1/4 turns for Z51 suspension, 2 3/4 for standard.
Almost all of the options were available individually as well (My '85 is not a Z51, but has every Z51 option that I know of for my year).
If you want more info, try a search, you'll find pages of threads about it.
And if you cant find the RPO list (in the center console or rear compartment), turn the wheel lock-to-lock, it should be about 2 1/4 turns for Z51 suspension, 2 3/4 for standard.
Last edited by mikey whipreck; Jun 20, 2006 at 11:42 AM.
Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
The RPO codes on my 1989 are on the inside of the center console lid.
In some earlier model years the Z51 was called Z52 I believe. The ZE7 heavy suspension and the J55 HD brakes were the main items. Also KC4 oil cooler, VO1 HD Radiator, some had NS fast ratio steering (but not all). Mine has blue and yellow Bilstein/Delco shocks.
Hope this helps.
In some earlier model years the Z51 was called Z52 I believe. The ZE7 heavy suspension and the J55 HD brakes were the main items. Also KC4 oil cooler, VO1 HD Radiator, some had NS fast ratio steering (but not all). Mine has blue and yellow Bilstein/Delco shocks.
Hope this helps.
Last edited by BADDUCK; Jun 20, 2006 at 12:18 PM.
Team Owner
Joined: Sep 2001
Posts: 62,171
Likes: 1,735
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
There is no Z52 in 86. Only Z51 and base.
The RPO sticker is in the rear compartment, driver's side.
The HP rating on the console is something the previous owner added.
Options would be the oil cooler, a standard 3.07 rear in 86, Auxiliary fan, different steering ratio, wider 9.5" rims front and rear, stiffer spring rates and stiffer Bilstein shocks, HD radiator, more chassis bracing as well
there were no brake changes for 86 Z51
The RPO sticker is in the rear compartment, driver's side.
The HP rating on the console is something the previous owner added.
Options would be the oil cooler, a standard 3.07 rear in 86, Auxiliary fan, different steering ratio, wider 9.5" rims front and rear, stiffer spring rates and stiffer Bilstein shocks, HD radiator, more chassis bracing as well
there were no brake changes for 86 Z51
Team Owner
Joined: Sep 2001
Posts: 62,171
Likes: 1,735
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Aluminum heads are not part of Z51, they werent an 'option', you either got them or you didnt. Only the later coupes have them, and all verts which are all base suspension.
You can see them easily by opening the hood and looking at the valve covers, if the bolts go around the perimeter its Iron, if they go down the center of the cover, its aluminum.
You can see them easily by opening the hood and looking at the valve covers, if the bolts go around the perimeter its Iron, if they go down the center of the cover, its aluminum.
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
vader has this one covered.
One of the easiest ways to check for Z51 in 86 is turn the steering wheel lock to lock. Z51 will do 2 turns (ok, 1.96 turns), base model is more.
I've seen "Heavy Duty radiator" mentioned a bunch of times, but have no clue what the actual differences are there. Knowing GM, it could just be a higher pressure rated radiator cap or something.
One of the easiest ways to check for Z51 in 86 is turn the steering wheel lock to lock. Z51 will do 2 turns (ok, 1.96 turns), base model is more.
I've seen "Heavy Duty radiator" mentioned a bunch of times, but have no clue what the actual differences are there. Knowing GM, it could just be a higher pressure rated radiator cap or something.
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Michael S. Palmer
Pro
Joined: Apr 2005
Posts: 590
Likes: 0
From: Boynton Beach, FL
Originally Posted by CentralCoaster
vader has this one covered.
One of the easiest ways to check for Z51 in 86 is turn the steering wheel lock to lock. Z51 will do 2 turns (ok, 1.96 turns), base model is more.
I've seen "Heavy Duty radiator" mentioned a bunch of times, but have no clue what the actual differences are there. Knowing GM, it could just be a higher pressure rated radiator cap or something.
One of the easiest ways to check for Z51 in 86 is turn the steering wheel lock to lock. Z51 will do 2 turns (ok, 1.96 turns), base model is more.
I've seen "Heavy Duty radiator" mentioned a bunch of times, but have no clue what the actual differences are there. Knowing GM, it could just be a higher pressure rated radiator cap or something.
86 Z-51 HD cooling system was an extra fan in front of radiator.
Larry
Intermediate
Joined: Feb 2003
Posts: 28
Likes: 0
From: Cincinnati OH
Z51
I have and 84 Z51. In 84 it was bigger sway bars, heaver springs, 2 1/4 turn lock to lock urathine bushings and the up grade to the Bilstein shock. A stand alone option was to have the 16 x 9.5 on the rears with the 16 x 8.5s on the front. This was pretty much the same through the the C4s. Withthe TPI there was a dual cooling fan. There was an option for a transmission cooler, but I think the radiator was the same. Get your self a Black Book will list all available RPOs. For your car contact the Corvette Museum and get a reproduction of your window sticker and the build sheet. A good thing if your build ticket is not in the storage well behind the driver on one of the sides. Hope this helps and have fun.
Race ON !!!!
Team Owner
Joined: Dec 1999
Posts: 34,873
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
You can purchase a copy of the window sticker and the build sheet from the National Corvette Museum. The window sticker will have the optional items that came on the car and the selling price of the options and the total price. It will also show the name of the dealer that ordered the car. The build sheet is what the assembly line workers used to add the required components and options on the car as it moved down the line.
Go heer to order them: https://store.corvettemuseum.com/ser...buildsheet.asp
Go heer to order them: https://store.corvettemuseum.com/ser...buildsheet.asp
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Originally Posted by Vetracr
86 Z-51 HD cooling system was an extra fan in front of radiator.
Larry
Larry
I replaced my radiator and it looked the same as the oem replacement.
