Hi

I have continued to search for a C4. I would appreciate feedback from anyone wishing to share on the following topics:

I understand that the '84-88 transmission is prone to failure--the 4+3, as it is called. How prevalent is failure? Are we talking 50,000 miles, 100,000 miles, or what is the expectation?

The Bose radio is a problem area it seems. Are these in all the C4s? Are they all eventually problems, or does it just seem that way?

If you can find one, does a hardtop fit on all C4s (convertibles that is)?

It appears that the 92-96s will likely have "Optispark" problems which are extremely costly to repair? Any comments?

From a novice standpoint, it would appear that the '89-91 might be the most reliable--or should I say, less costly to own? I think a '92-96 would be more desirable, but not really wanting to get into the Optispark thing.

Thanks for any feedback.

Bruce

 

Avoid the 84 at all costs. My 85 was twice the car as the 84

 

As with any "Used Car", buy the newest and nicest one you can afford.

Worst mistake anyone can make buying a used Corvette (of any year), is buying one that needs work thinking they can fix it up since it's such a good buy.
Unless you know what your doing and can do the work yourself, you'll spend more money fixing one with problems than buying a nice one to begin with.

Oh, and don't let the OptiSpark scare you out of a '92-'96, especially a '96. There are literally thousands of them on the road without any issues at all.

 

I have the 4+3 in my 88 and it's great. A very good transmission provided it gets the maintenance it needs. I enjoy driving it and I've gotten as much as 29mpg on the highway. I used to own a 93 with the Optispark. Never had a problem with it. The issues with the opti involved moisture ingress, but I think it was in 94 that they became vented to help alleviate the issue. Never spray water or carelessly steam clean an optispark engine. It really comes down to how well the car was maintained, regardless of the year. Insist on looking only at cars where the owner can document the history and maintenance of the car. This, of course, means avoiding most cars at dealerships and instead taking your time to look at cars from private owners. (Few dealerships pass on the complete maintenance history even if it's given to them.)

 

The convertible hardtop fits 89 to 96 only. They can be retrofitted to the 86 to 88 verts and I have actually done this. There is also a company named Smoothline that makes a top that will fit all C4 verts. Very expensive though.
If you find a good candidate then get one of the C4 owners who live nearby to go look it over with you. I'd also slip them a couple hundred for their trouble as this knowledgeable person could save you thousands.

 

[QUOTE=Bruce_in_MN;1572256804]Hi

I have continued to search for a C4. I would appreciate feedback from anyone wishing to share on the following topics:

I understand that the '84-88 transmission is prone to failure--the 4+3, as it is called. How prevalent is failure? Are we talking 50,000 miles, 100,000 miles, or what is the expectation?

The Doug Nash 4+3 tranmission is a 4 speed manual with an automatic overdiver unit on the top 3 gears. The major problems arise from inadequate maintanence of the auto unit; i.e. not changing the trans fluid on a regular basis. The transmission itself is very strong, these were the units installed on the Callaway Twin Turbo cars.

The Bose radio is a problem area it seems. Are these in all the C4s? Are they all eventually problems, or does it just seem that way?

The Bose radios were the only factory units installed in the C4. Many have had problems (my 93 works perfectly). The problem with replacement is that the Bose system used separate amplifiers in the speakers rather than the head unit. So to replace a Bose unit requires replacement of the speakers as well.

It appears that the 92-96s will likely have "Optispark" problems which are extremely costly to repair? Any comments?

The opti is a very good unit but is susceptible to moister infiltration. The problem is it's installed under the waterpump and coolant will definitely kill it.

 

You will find in most cases the mechanical problems with the 4+3 have long been fixed .Many owners of these cars are now showing up on this forum with with operational problems as age takes it toll on parts in the O/d elec control system ( switches / relay / wiring )
Easy and cheap to fix with help from here.

 

Although the newer C-4's have improved greatly my 84 hasn't been a bad a car as everyone says they are. You do have to remember they are lower in hp and rougher riding but just as much fun as any other vette. My wife's 07 with run flats doesn't ride too well on a rough road either.

 

The best thing to do when searching for a C4 (or any other generation) is to buy the best car you can for the money you have to spend.

For example, if your budget is say $10K, you should be looking at the 92 and later C4's If your budget is $5 to 7K then you are in the 86-91 territory. Buying a fixer-upper can be a cheap start, but if you don't have the tools, knowledge, and expertise to bring a car up the level you want, it's going to cost lots of money.

Each of the major versions of the C4's (84-87, 88-91, 92-96) will have their own little quirks and problems. The trick is to find one that has had all of the problems ironed out or at least find a car that has been very well maintained and not driven hard. There is no reason why your search can't last for 2-3 months and maybe cover the states around your area.

You should initially concentrate on which body style you want; like a coupe or convertible. Either one can be great fun, but they can be different in terms of what you expect of a Corvette. Second, decide if you want a manual or automatic trans. Both can be fun to drive, but you have to decide which one works for you.

Consider the suspension too, the base suspension cars have a decent ride but still drive like a sports car. The optional suspensions like Z51 in the early cars and Z07 in the later C4's will have a harsher ride, but will exhibit improved handling. Convertibles typically didn't get the optional Z51 or Z07 suspensions so that's another consideration.