An LT1 in ZR-1 clothing

[Dirtfarmer]

I test drove a '93 Corvette today and thought I might be able to turn to the C4 boards for a little advice. First off, a previous owner made the car look like a ZR-1 (wide tires and body, wagon wheels and rear ZR-1 badge). We realized it wasn't a ZR-1 when we popped the hood. In addition, it had a chip and aftermarket exhaust. I've never heard of it, but someone spent some time and money making this car look like a Z. All in all, a very nice car. Drove well and felt good pulling through the gears.

So here are the questions; Did all ZR-1's have the valet switch and were any made with removable tops? Was it/is it common for people to "dress up" a LT1 in ZR-1 clothing? This car has the opti-spark dist, is this something to be concerned about?

I appreciate any response to these questions. I have a few more but will save them for now.

 

[Jeffvette]

Some people have wired up the Valet switch for Nitrous Applications. All ZR-1's had the valet switch. 90 you could select on and off and leave it that way. 91-95, system defaulted to the off position when the car was turned off. You have to make sure to turn it to "FULL POWER" after starting it. There are some aftermarket harnesses to defeat that.

The body kit, there are a few out ther supporting the door/rear quarter/bumper/rocker panel treatment. It's expensive to do. All ZR-1's were coupes and had removable tops. If it had wagon wheels on with the correct ZR-1 body work, the rear wheels would be sunk in, unless they used spacers.

Having the optispark sucks. The ZR-1 is a waster spark system with the DIS.

 

[Dirtfarmer]

Thanks jeffvette.

This car had the sunken hubs on the rear wheels. To the best of my knowledge, this car was a ZR-1 until we opened the hood (where it really counts). Alas, only a good impression of a ZR-1. Thanks also for the answer on the valet switch and removable top.

The car is a beauty, our biggest concern is the opti and how reliable it is. The best I can gather is that this car is probably due for a new one (83,000 miles).

 

[c4cruiser]

The VIN holds the information as to whether or not the car was a "real" ZR1:
The 5th digit of the VIN determines the carline/series. A "Y" indicates a LT-1 motor and a "Z" indicates a ZR-1.
1G1YY = LT1 car
1G1YZ = ZR-1
The 8th digit in the VIN is the engine number:
J = LT5
P = LT1
The last 6 digits of the ZR-1 VIN's started with 800001 and ended with 800448

All ZR-1's had FX3, Electronic Climate Control, Sport Seats, LTPWS, and a different tach/speedo display. There was also a specialt tinted windshield with a small "clear" area in the bottom of the windshield right in front of the driver ostensibly for a "garage door opener" The windshield had a metallic coating and some openers wouldn't work thru the glass. Funny thing but radar detectors wouldn't work either

 

[Dirtfarmer]

Thanks c4cruiser.

Looking under the hood proved that the car isn't a ZR-1, just a copy. I double checked the VIN when I got home just to make sure since I had only seen photos of the LT5. Once again the CAC tech center cleared up any questions.

Like I mentioned before, we are mostly concerned with the opti spark. I've searched the forums in the past trying to learn about the opti but haven't had a lot of time this weekend to brush up. I've got a little time right now so I'm going to see what I can find in past posts.

Since the car has a body kit, does it make it any more troublesome if body work is needed in the future?

 

[Jeffvette]

Rear clip and rear bumper discontinued by GM as has all the associated molding.

 

[Dirtfarmer]

Thanks, good to know.

 

[c4cruiser]

The Opti is not terribly troublesome by itself. Getting the unit wet will effectively ruin it and will require replacement. Being below the water pump is a problem, so if there is any indication of a leaky pump, replace the pump immediately.

Also when flushing coolant you need to open two bleed valves: make sure that coolant coming from the bleed valves does not flow down onto the Opti. One is on the thermostat housing and the other on the driver's side of the throttle body.

The later (95-96) Opti had a vacuum line leading to the cap and that helped to keep moisture out. It can be retrofitted to the earlier caps but it does require R&R of the Opti to do it.

MSD now makes a billet version of the Opti so you have an alternative for a replacement. The price is about the same as the GM unit.

I drove my 92 for close to 8 years and never had a problem with the Opti. I did replace the OEM plug wires and used MSD Heli-Coil 8.5mm wires. They were not that difficult to do but the size of the wire was much larger than OEM so I had to do come custom work on the plastic wire clips.

Does the car have the FX3 Selective Ride Control?? While FX3 is a great system, it can be expensive to repair. Shocks are around $200 each ($150 ro bebuild by Bilstein), and the actuators can run to hundreds of dollars! My 92 had FX3 and I really liked it. I did have to have one shock rebuilt after the small pot metal gear on the top of the shock rod broke. The gear is not available by itself (either from GM or Bilstein) and Bilstein will only replace the gear as part of a rebuild.

One of the best things you can do is to get a GM Service Manual for the car. Go to www.helminc.com and order a 93 manual. You get the same manual that the GM techs use. Lots of great technical information if you intend to do any sort of work on the car yourself. You might find them from time to time on eBay or here in the parts for sale sections.

 

[BLACKTALON]

A hard core vette guy would know the difference.I could take a 5 sec look at the thing a tell its a fake.He/she would not come around my club wit that car.:L some of the guy's would Take my car its the same color as a Grandsport,just some stickers/fender hashs,and I've got a grandsport.:nono Its like who are you fooling:L

 

[Dirtfarmer]

Thanks everyone for your input. After thinking about it for a day we've decided against it. The main reason being that it would always be a ZR-1 knock-off, I couldn't get that out of my head (although it is a beautiful car). I kept thinking about a thread I read here about a guy that really wanted a '53 but couldn't afford one. He was willing to spend some money and build a '53 kit and in the end that's what it would be, a kit car.

Something else I've learned reading these forums that I couldn't get out of my head; you're better off finding the car that's right for you than settling for one that isn't.

Thank you again, all of your input is appreciated.

 

[BLACKTALON]

Just sit back and think A ZR1,whats different, THE WHOLE CAR. just one look under the rear and your busted!! The tach,ya busted,the 3rd brake light,ya busted, and the Z is wider than a avg C-4,ya busted,The windshield,busted,the sound,gess what ya busted,Do I need to mention opening the hood?????? Hell Ya busted!!!!! :L

 

[KREX 725]

Maybe I'm missing something, but if it's that nice of a coupe (unless you are specifically trying to find a ZR-1), why not buy it and take the ZR-1 badge off the back? The rest of the mods aren't too terribly crazy for a coupe.

 

[Dirtfarmer]

The car had a body kit to give it the ZR-1 wide body. More than a matter of pulling off a badge and changing tires/wheels. Someone will buy that car and have a lot of fun with it but it won't be me.

If I find the right ZR-1 I'll buy it for the performance of the LT5, not for the "look" of a ZR-1.