DIYDanCars

Hello guys, I’m considering purchasing a 4+3 85 or newer C4 Corvette and had a few questions for you. I noticed some of the targa top C4’s for sale come with both a glass top, and a body colored top. Should all targa top C4’s come with both tops? What documentations and or tools should the car come with? I assume C4’s came with a owners manual for the glove box and a tool to remove the top?

For a performance oriented guy that would like to find a car with the Z51 performance package and “sport seats”. Are there any other options I should be looking for too?

Thanks

PatternDayTrader

Newer is almost always better.

CRAIGVETTE

No, having both targa tops was just an option. Most C4s will just come with either the fiberglass body colored top, or the glass top. Again, it is just and additional cost option to have both tops.

A ratchet tool and the owners manual should be in the center console for targa top removal.

Only the 90-93 C4s have glove boxes. The 84-89 just have a thick pad known as the "breadloaf" where you think a glove box would be (although a lot of owners have removed these and replaced them with aftermarket flat panels. They even used to make an aftermarket retrofit glove box, but they are no longer made). The 94-96 have a passenger airbag where the glove box was located at on the 90-93 C4s.

If you are looking for the best performing C4, look at the 96 with the LT4 engine, or of course the 90-95 ZR1s with the LT5 engine.

c4cruiser

I had an '87 coupe that I had used as an autocross car and really liked it. It had a 4+3 and the Z52 sport suspension package. The intended purpose was to just have a Corvette that I could drive regardless of the weather. When it poured down rain and I wanted to drive a Corvette, that was the car I took out of the garage, turned on the wipers and took off!

I was a big fan of the 4+3 but I would now recommend finding an 89 or later car with the ZF 6-speed manual trans. With the 4+3, it's getting hard to find parts and there is only one or two places that have lot of experience rebuilding/repairing them. Fluid changes for the OD is an annual activity (or every 12K miles). The OD unit was selected for the 84-88 trans so that Chevrolet could meet the CAFE fuel economy requirements in effect at the time.

There were two targa tops available for the coupes, You could pick the solid painted top or the tinted see-thru top. Or you could have chosen the option for both tops. As mentioned, the coupe came with a small ratchet and Torx T-40 socket for removing/replacing the targa top.

The optional Z51 suspension was popular throughout the C4 production years. Stiffer springs and Z51-specific Bilstein shocks, larger sway bars, oil cooler, and wider front wheels were also part of the package. Beginning with the 1990 model year, the Z51 package was re-designated as Z07. This package kept all of the earlier components but the FX3 Selective Ride Control replaced the Z51 shocks.

It's always a good idea to look for the best car for the money you have to spend. It can get pricey to buy parts and do some repairs so a car that's ready for you to climb into a car with little fear of breaking down is the best way to go. Then you can start to build a plan for mods that you want for increased handling and performance.

N227GB

Check the RPO (Regular Production Options) sticker for C2L. That's the code for both body color and tinted roof panels. If a particular car you're looking at has this RPO but only one panel, that's a bargaining chip for the price.

hcbph

One more thing to watch in your selection - wheels & tires. the 84-87 model years had 16" tires with a 32 or 38 offset rim. That in and of itself isn't a show stopper but have ramifications down the road.
16" tires are getting hard to find and if you want some other rims, few are made to fit these years (though there are a few available if you really look hard) unless you like using spacers to make 56 mm offset rims work.
88 and up have 17" rims and 56 mm offset rims which pretty much the standard ever since.
I have an 86 and wanted different rims and tires, went with 18". I did find them and they fit like a glove but it's something you have to work at to locate.
The other thing is the newer the car, the easier it is to find parts vs the older ones. Some parts are no longer available so used may be your only sources.

Don't take any of this as negatives just things to watch out for. I've an 86 and I love it and will keep it as long as I'm able to drive.

DGXR

...and if you want a manual C4, the 6-speed in the later models is a very nice (and strong) transmission. I can't say there's anything wrong with the 4+3, I have no personal experience with it, but the ZF6 is generally regarded as superior. I love my LT1/ZF6 combination, such a pleasure to drive.

Since you are a performance-oriented guy shopping for a C4:

1991 is the only year with the L98 engine available with ZF6.
1992-1995 all had the LT1 engine (except ZR1).
1996 cars with the 6-speed all got the uprated LT4 engine (1-year engine option, 1996 only).
1996 cars with the automatic got the LT1.
... if I recall the year combinations correctly

The HD suspension package (Z51?) came with 17x9.5 wheels all-around. Most C4s have a staggered wheel set -- the rears are wider than the fronts.

The FX3 option has adjustable damping shocks. A good system, but often expensive to repair or replace parts.

Some C4s were optioned with the spare tire delete. The rear-collision safety was retained through the installation of a metal brace/bar in the place where the spare tire used to be. This delete option saves weight.

DIYDanCars

Thanks fellas! I'm partial to the years with the digital dash. As an 80's guy, I really love the interior of the older C4's vs the newer ones. I also prefer the wheels from the early cars too.

From what I have read, the 4+3 transmission had most of the bugs worked out by 1986. A couple of people I talked to as well a few internet sites made it sound like as long as I keep up on the fluid changes, the transmission will provide me with many miles of enjoyment. Is this not the case? I'm also looking for a C4 with under 50k miles and a documented history. Hopefully this will improve my chances of getting a well cared for Vette.

No doubt these cars are old and as I person who owns 5 other 80's cars, parts availability and tires can sometimes be challenging, I definitely understand that! Since Chevrolet made so many C4 Vettes, i'm kind of surprised to hear that some of the parts may be getting hard to find.

I really appreciate the feedback!

JD Shredds

Is there a particular reason you want a 4+3 car? It seems performance wise you're more focused on handling than power if you're looking early Z51 cars, unless its just a matter of lower budget.

I personally get it. I have a weird love for 80's cars in spite of their shortcomings, and I see you do too. I love the way things were done back then.

Do you intend to do a build or mostly enjoy it as-is?

Good post, but quick correction: The ZF6 was introduced in 1989, so it had a 3 year run with the L98 engine. Also new in 1989 was the FX3 adjustable suspension option. 1990 introduced the new interior style. 1991 the new body style. 1992 the LT1 engine. 1988-1992 offer a very unique transition period.

Also of note: the earlier Z51 packages were also on 9.5 wide wheels like later models, but 16 inch diameter (1984-1987) instead of 17 inch (1988+).

DIYDanCars

Yea, I'm a big 80's car guy. I love the rawness and styling of these older vehicles.

I want a manual transmission, I don't care if it's a 4+3 or ZF 6 speed as long as it's in a color combo I like. However, i'm not seeing many 89' cars for sale. I do have a much bigger selection to choose from if I go 4+3.

Will the 16" wheels fit on the later cars with the bigger brakes? I'm guessing not, hence the 17" wheels?

C5 4me

1st I envy you,or anyone that has a 928 in the garageAlways a dream car of mine! & good hunting for your C4,You should be able to find a nice 1.I find getting in and out of them sucks as you get older,but once your in its a wonderful ride.

DIYDanCars

The Porsche 928 has been my first love since I was 7 years old. I remember seeing a white 928 S4 at a gas station in 1988 (7 years old) and fell in love right then and there. I now have two 928's, the red 85 pictured above and a 87' 928 S4. If I can maintain my 928s myself, i'm thinking a C4 Corvette can't be any worse. Right?

Lingenfelter

Just curious if that 928 is a stick, since most came with the automatic transmission. Is that a 944 Turbo? Nice cars!

C5 4me

I would think that the 928 would be harder to work on and more expensive as well,somehow I see a ZR1 in your futureMy 1st boss took me for a joyride in his when I was younger... I will never forget that he told me that I scream like a girl! That was the wildest ride in my 56 years of living & one of my best memories.

N227GB

You are going to LOVE the clamshell hood of the C4. Here on the forum I once posted a picture of a 928 with the hood open as an example of something hard to work on.

Still, a 928 is on my short list of cars I'd like to own.

QCVette

I have had two 4+3 cars ('85 & '87) and four ZF6 cars ('94, '94, '95, '96). Although I didn't have big problems with the 4+3's, I like the ZF6 much better. They shift better, they are stronger, and I like the spread of ratios better. The most noticeable part is the shifting. The 4+3 has an external shifter and has a "clunky" feel to it (if that is a real word?) and I found I only used the OD as a 5th gear on the highway. The transmission was one of the reasons I sold my '85 to get a '95.

The suspensions were changed in '88. The '84 to '87 wheels have a different offset so they don't fit the later cars well. The '88 did have 16" wheels as standard and will fit the later suspension cars if they have the base brakes. I ran the '88 16" wheels on my '94 as my winter wheels. They do not clear the J55 option brakes. Most cars do not have the J55 brakes. They were generally used with the performance suspension options until they J55 brakes became standard and the only ones used in '95 & '96.

Good luck with your choice.

DIYDanCars

Unfortunately both are automatics. Yep that's a 87 944 Turbo with a few modifications done, it laid down almost 300 hp at the rear wheels on the last dyno run. Not bad considering i'm still using the stock turbo.

LOL! I think you're right! Yea, 928's are definitely not the easiest to work on. I currently have the engine removed from the red car so we can rebuild it. I also had custom pistons made to lower the compression ratio so we can throw some boost at it. That should really bump the power up.


Cool thanks! That was really helpful! I think it's time to do some test driving. I think most sports cars from the 80's had that "clunky" or what I like to call, notchy feel to them. It's part of the charm?

mazdaverx7

Love your car collection!! I'm also an avid 80' Porsche fan. I have a custom ordered M456 944 that I've been restoring.



Its tough to find the 928 with a manual trans. I've been keeping my eye out for a decent one to restore. They take a special hand when working on them that's for sure. I love 80's sports car. I'm a Mazda RX-7 restoration guy that ventured into Corvettes after one drive with a buddy. I can tell you that the 4+3 trans is excellent.I have an 86 with the 4+3 and I love it!! Would never have an automatic anything. You are asking all the right questions before jumping into a purchase. I would start browsing some for sale ads and drive a few examples and see how you like the 4+3 over the ZF 6 speed. To me, either is more than fine but some people prefer one over the other.

DIYDanCars

Cool another 80's guy! I have been following your 944 thread on rennlist. Nice work so far!

Thanks! I think you're right, it's time to start test driving. The ones I have looked at so far have been really ragged out. The interiors in these cars don't seem to hold up to well, even on the low milers.

mazdaverx7

I appreciate you following my thread. I've done a lot to the car but it needs much more. I have 14 cars actually and most are from the 80's. I grew up in the 80's and always dreamed of having a collection of new (80's) cars when I was a kid. I'm doing what I can I suppose.

A lot of the bargain priced C4's are in need of work. Its hard to find a good middle ground with these cars honestly. They either need a tn and are priced cheap or they are amazing and are priced accordingly. I bought my 86 4+3 last spring and it needed a few things. Its a driver quality car, which is what I wanted, and it now runs and drives well. Still needs tires and a new steering wheel, the speakers' amps are bad, the carpet is faded etc. But, I paid only $3600, which I thought was a fair deal for the car. Driving a few decent examples will put you on a path to what you want. You'll figure out what you can live with and what needs replaced. You'll have a good idea of common issues and you'll find one that's right for you.