ZO7 C4s
Team Owner
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From: Life's tough, wear a helmet.
Originally Posted by MarkBychowski
You're right, most people don't even know they have a Z07. The stupid ones tell you there's no such thing.
Team Owner
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From: Life's tough, wear a helmet.
Originally Posted by jack the stripper
i have a Z51 equipped 89' coupe.
Edit: With the factory A4 you do not have Z51.
Melting Slicks
Joined: Apr 2000
Posts: 3,490
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From: Oviedo FL
Originally Posted by CentralCoaster
I don't think there really is a difference per se, it's just a name change.
The General changed the name from Z51 to Z07 in '91, then changed it back in '96.
The General changed the name from Z51 to Z07 in '91, then changed it back in '96.
Z07 option also included the FX3 option whereas the Z51 option did not. In a nutshell the Z07 option included the following:
J55 brakes with 13" rotors in the front (these came standard in 95)
FX3 adjustable shocks
30mm front and 24mm rear sway bars - both solid (Z51 came with 26mm in the rear)
stiffer springs (Z51 was stiffer in the front and same stiffness in the rear)
stiffer bushings
275/40 tires all the way around
Mike
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From: Life's tough, wear a helmet.
Originally Posted by luvmy92
There is a big difference:
Z07 option also included the FX3 option whereas the Z51 option did not. In a nutshell the Z07 option included the following:
J55 brakes with 13" rotors in the front (these came standard in 95)
FX3 adjustable shocks
30mm front and 24mm rear sway bars - both solid (Z51 came with 26mm in the rear)
stiffer springs (Z51 was stiffer in the front and same stiffness in the rear)
stiffer bushings
275/40 tires all the way around
Mike
Z07 option also included the FX3 option whereas the Z51 option did not. In a nutshell the Z07 option included the following:
J55 brakes with 13" rotors in the front (these came standard in 95)
FX3 adjustable shocks
30mm front and 24mm rear sway bars - both solid (Z51 came with 26mm in the rear)
stiffer springs (Z51 was stiffer in the front and same stiffness in the rear)
stiffer bushings
275/40 tires all the way around
Mike
The bummer is that when have the Z51+FX3 setup you don't have true Z51 springs. You get softer springs.
I think J55 was standard with all Z51 packages from 1989 forward.
In 1989 Z51 could not be had with an automatic transmission.
Melting Slicks
Joined: Apr 2000
Posts: 3,490
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From: Oviedo FL
Originally Posted by Scoob
My '90 with Z51 has FX3.
The bummer is that when have the Z51+FX3 setup you don't have true Z51 springs. You get softer springs.
I think J55 was standard with all Z51 packages from 1989 forward.
In 1989 Z51 could not be had with an automatic transmission.
BTW, I take it pompous is a compliment?
Mike
Team Owner
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From: Life's tough, wear a helmet.
Originally Posted by luvmy92
Didn't the 91 car come with the stiffer springs when mixing Z51 and FX3? If I'm not mistaken it was the only year to do that.
BTW, I take it pompous is a compliment?
Mike
Mike
Melting Slicks
Joined: Apr 2000
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From: Oviedo FL
Originally Posted by Scoob
Not if I'm reading this correctly. http://vettenet.org/susp_chart.html
Originally Posted by Scoob
Uh, sure.
Team Owner
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From: Life's tough, wear a helmet.
Originally Posted by luvmy92
Actually, 91 was the first year for Z07 and they did combine Z51 with FX3. Notice the front spring rate is the same as the 90 Z51 car (115.5). In 92 they softened the spring rate to 90.1, which appears to be slightly softer than every spring used from 88 - 91.
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Le Mans Master
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From: Why are there squished peanut butter cups in my underware?
From Corvette Quarterly, Fall 1990 issue, page 46
The Z51 package for 1989 and 1990 required a manual transmission and was not available on convertibles. FX3 in 1989 required Z51 and was therefore also limited to manual transmission coupes.
"FX3 with Z51" (1989 & 1990) has been a source of some confusion to owners since it really gave you the softer suspension calibrations of the base car. The difference was that Z51 brought with it heavy duty brakes, engine oil cooler, finned power steering oil cooler, and larger front air dam.
In 1991, the Z51 designation has been dropped, both in adjustible and non-adjustible form. It was replaced with an adjustible system known as Z07. It provides all the heavy duty components of the old Z51 package with the FX3 system.
Yea, I'm pompous
The Z51 package for 1989 and 1990 required a manual transmission and was not available on convertibles. FX3 in 1989 required Z51 and was therefore also limited to manual transmission coupes.
"FX3 with Z51" (1989 & 1990) has been a source of some confusion to owners since it really gave you the softer suspension calibrations of the base car. The difference was that Z51 brought with it heavy duty brakes, engine oil cooler, finned power steering oil cooler, and larger front air dam.
In 1991, the Z51 designation has been dropped, both in adjustible and non-adjustible form. It was replaced with an adjustible system known as Z07. It provides all the heavy duty components of the old Z51 package with the FX3 system.
Yea, I'm pompous
Last edited by Z-07 freak; Nov 22, 2005 at 04:04 PM.
Safety Car
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From: Southwest Kansas
2022 Corvette of the Year Finalist -- Unmodified
2021 C6 of the Year Winner - Unmodified
You're right to say that most people don't even know what Z07 is, and I was no different. It was not until I checked my RPO codes that I found out my 94 A4 had it, and then I wasn't sure what it was until I posted here and did my research.
Is it worth more? Maybe to the right person, but the average joe probably won't want it as it is definitely a harsher ride, but the handling characteristics are fantanstic.
Is it worth more? Maybe to the right person, but the average joe probably won't want it as it is definitely a harsher ride, but the handling characteristics are fantanstic.
Last edited by teebee; Nov 22, 2005 at 10:20 PM. Reason: add picture
Melting Slicks
Joined: Mar 2005
Posts: 2,352
Likes: 230
From: Northeast FL
For model year 1988 the differences were as follows according to the Covette Black Book.
Z52 consisted of the radiator boost fan, Bilstein shocks, and the oil cooler.
Z51 came with those options and added the heavy duty radiator and heavy duty suspension. Only available on manual coupes.
They both came with 17 X 9.5 wheels and the faster steering rack.
From what I see in the book, Z52 was only available in '88. I thought it was available for a couple of years but apparently not.
Z51 specs changed depending on model year.
Z52 consisted of the radiator boost fan, Bilstein shocks, and the oil cooler.
Z51 came with those options and added the heavy duty radiator and heavy duty suspension. Only available on manual coupes.
They both came with 17 X 9.5 wheels and the faster steering rack.
From what I see in the book, Z52 was only available in '88. I thought it was available for a couple of years but apparently not.
Z51 specs changed depending on model year.
Team Owner
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Originally Posted by luvmy92
There is a big difference:
Z07 option also included the FX3 option whereas the Z51 option did not. In a nutshell the Z07 option included the following:
J55 brakes with 13" rotors in the front (these came standard in 95)
FX3 adjustable shocks
30mm front and 24mm rear sway bars - both solid (Z51 came with 26mm in the rear)
stiffer springs (Z51 was stiffer in the front and same stiffness in the rear)
stiffer bushings
275/40 tires all the way around
Mike
Z07 option also included the FX3 option whereas the Z51 option did not. In a nutshell the Z07 option included the following:
J55 brakes with 13" rotors in the front (these came standard in 95)
FX3 adjustable shocks
30mm front and 24mm rear sway bars - both solid (Z51 came with 26mm in the rear)
stiffer springs (Z51 was stiffer in the front and same stiffness in the rear)
stiffer bushings
275/40 tires all the way around
Mike
I guess my point was Z07 replaced Z51. They can't be compared since they were not available in the same year, unless I am mistaken. I bet GM killed the Z07 option because they didn't want it confused with the up and coming z06 option.
Melting Slicks
Joined: Apr 2000
Posts: 3,490
Likes: 2
From: Oviedo FL
Originally Posted by CentralCoaster
I guess my point was Z07 replaced Z51. They can't be compared since they were not available in the same year, unless I am mistaken. I bet GM killed the Z07 option because they didn't want it confused with the up and coming z06 option.
You are correct, they were not available in the same year. As was mentioned earlier, 91 was the only year where Z51 and FX3 were combined (and called Z07), as all later year Z07 cars came with a softer spring in the front and a smaller sway bar in the rear. Z07-Freak said this was because in 92 they switched from Gatorbacks to GSC's.
I think they killed the Z07 because there wasn't enough interest in it. They only sold 7 - 800 a year during the run. But what do I know.
Mike
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From: Why are there squished peanut butter cups in my underware?
Originally Posted by luvmy92
91 was the only year where Z51 and FX3 were combined (and called Z07)
Wacha talkin about Willis?I meet Dave Hill once, and I asked him why the Z-07 was dropped. He simply said, if someone want an off road racer, it's easier for that person to make the changes to their Vette themselves, ratther than making it a factory option. I thought it was a weak answer. Or maybe because it was McLellans idea to begin with.
Last edited by Z-07 freak; Nov 23, 2005 at 10:39 AM.
Melting Slicks
Joined: Apr 2000
Posts: 3,490
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From: Oviedo FL
Originally Posted by Z-07 freak
Wacha talkin about Willis?From 92 and up they went with the softer front spring and slightly smaller rear sway bar (24 mm).
And I agree about the Dave McLellan statement. I doubt if those guys got along. McLellan was a genius compared to Hill (have met McLellan a number of times).
As good as the Z07 setup is it can still be improved upon. I had my shocks revalved and went the DRM controller prom and removable chips.
Mike
Le Mans Master
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Posts: 7,276
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From: Why are there squished peanut butter cups in my underware?
Originally Posted by luvmy92
First year Z07 cars (91) had the the same Z51 springs and sway bars as past Z51 cars. They actually combined the Z51 suspension with the FX3 shocks.
From 92 and up they went with the softer front spring and slightly smaller rear sway bar (24 mm).
From 92 and up they went with the softer front spring and slightly smaller rear sway bar (24 mm).
teebee1994 and I think alike.
Drifting
Joined: Apr 2005
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From: St. Louis, Mo......... 1993 Torch Red w/White Interior...2006-07 Bloomington Gold 2005-ZR1/C4 Gathering, 2001-2012 Funfest
Originally Posted by luvmy92
And I agree about the Dave McLellan statement. I doubt if those guys got along. McLellan was a genius compared to Hill (have met McLellan a number of times).
Mike
also. Dave McLellan is the nicest guy in the world. He will stop what he's is doing if you want to talk to him. Hope the next Chief Engineer follows in Dave's footsteps when it comes to being around us "regular folks".Rik
http://photobucket.com/albums/y126/Riks40th/
