Z51 experts
Thread Starter
Melting Slicks
Joined: Nov 2010
Posts: 2,216
Likes: 113
From: Michigan
Z51 experts
Ok finally looked at my RPO sticker and turns out I bought a Z51 for my street/drag project. Not sure if I should be bummed or happy. After looking at several cars I wasn't worried about options, was hard enough to find a good cheap car. Paint/interior is good, miles aren't too high and it runs and drives great.
Anyways I just wanted to ask if the brakes are the same for a 86 z51. From what I can tell the only 86 z51 differance is gear, sway bars, shocks, springs, wheels, power rack, radiator. Wheels I was gonna sell anyways, but now the rack and front sway bar might be worth taking the time to sell. The rad, gear and stiffer springs I can work with.
Oh and what is the speedometer adapter & key deletes codes all about?
Anyways I just wanted to ask if the brakes are the same for a 86 z51. From what I can tell the only 86 z51 differance is gear, sway bars, shocks, springs, wheels, power rack, radiator. Wheels I was gonna sell anyways, but now the rack and front sway bar might be worth taking the time to sell. The rad, gear and stiffer springs I can work with.
Oh and what is the speedometer adapter & key deletes codes all about?
Le Mans Master
Joined: Jun 2009
Posts: 6,528
Likes: 752
From: South Dakota
The brakes are the same for all '86's.
The Z51 included
B4P Radiator boost fan
FG3 Delco-Bilstein shocks
KC4 Engine oil cooler
V01 Heavy duty radiator
9.5" Wheels
HD suspension (see chart at http://corvetteactioncenter.com/tech/c4/susp_chart.html )
Fast ratio steering.
If it was a 4+3, it also got the .67 ratio overdrive (instead of the .59 ratio)
I am not sure which gear was used, but the codes are below.
G44 - Rear axle 3.07 ratio
G87 - Ring gear 8.50 inch
G92 - Rear axle performance ratio
GH0 - Rear axle 3.54 ratio
GM1 - Rear axle 2.59 ratio
GM3 - Rear axle 3.45 ratio
GT7 - Rear axle 3.33 ratio
GU2 - Rear axle 2.73 ratio
GW4 - Rear axle 3.31 ratio
HE3 - Rear axle 3.07 ratio
The Z51 included
B4P Radiator boost fan
FG3 Delco-Bilstein shocks
KC4 Engine oil cooler
V01 Heavy duty radiator
9.5" Wheels
HD suspension (see chart at http://corvetteactioncenter.com/tech/c4/susp_chart.html )
Fast ratio steering.
If it was a 4+3, it also got the .67 ratio overdrive (instead of the .59 ratio)
I am not sure which gear was used, but the codes are below.
G44 - Rear axle 3.07 ratio
G87 - Ring gear 8.50 inch
G92 - Rear axle performance ratio
GH0 - Rear axle 3.54 ratio
GM1 - Rear axle 2.59 ratio
GM3 - Rear axle 3.45 ratio
GT7 - Rear axle 3.33 ratio
GU2 - Rear axle 2.73 ratio
GW4 - Rear axle 3.31 ratio
HE3 - Rear axle 3.07 ratio
Team Owner
Joined: Sep 2003
Posts: 25,377
Likes: 2,735
Ok finally looked at my RPO sticker and turns out I bought a Z51 for my street/drag project. Not sure if I should be bummed or happy. After looking at several cars I wasn't worried about options, was hard enough to find a good cheap car. Paint/interior is good, miles aren't too high and it runs and drives great.
Anyways I just wanted to ask if the brakes are the same for a 86 z51. From what I can tell the only 86 z51 differance is gear, sway bars, shocks, springs, wheels, power rack, radiator. Wheels I was gonna sell anyways, but now the rack and front sway bar might be worth taking the time to sell. The rad, gear and stiffer springs I can work with.
Oh and what is the speedometer adapter & key deletes codes all about?
Anyways I just wanted to ask if the brakes are the same for a 86 z51. From what I can tell the only 86 z51 differance is gear, sway bars, shocks, springs, wheels, power rack, radiator. Wheels I was gonna sell anyways, but now the rack and front sway bar might be worth taking the time to sell. The rad, gear and stiffer springs I can work with.
Oh and what is the speedometer adapter & key deletes codes all about?
Your '86 likely had a D3X if it was a "domestic" build. If it's NOT D3X what is it? The delete should have been E?C or maybe E?Z. I haven't looked at an early SPID label in quite some time but those should explain the D's and E's you had questions about. Any others you're unsure of?
Team Owner
Joined: Sep 2003
Posts: 25,377
Likes: 2,735
That information would have also been on the production "build sheet" that went with the chassis down the assembly line and those id's are what was used by the assembly line workers to know that the correct items were added to that particular car. That information could also be used by experienced parts personnel to ID replacement parts when needed.
