I was hoping to get educated rather quickly on purchasing a C4. I have a C3 and would like to add a C4. I will be looking at a 87 convertible locally and would appreciate any assitance/tips on what to look for and what to run away from in a C4. If you could point me to a thread in this forum that would be swell too.
Thanks

 

Few links that are seen commonly sure the guys will post them up.

Like any car check the basics..start easy run hot? ALL the electrical work?
Should idle pretty smooth.
On an EFI car I look at the wiring harness if I can. If its hacked up with stuff bypassed I walk. Looks past the pretty paint and cosmetics and pay attention to the rest of it. In my mind all potential purchases are in primer so I dont get sucked into the way something looks. btdt.

 

Condition is the big thing, paint and interior work is cost prohibitive. Check it out for extended times to make sure it isn't overheating (common problem on 80's C4's, head gaskets an issue on 86L-91)) Make sure the dash is working. Make sure the compressor is not rattling. Tires are becoming a problem for those cars because they were the only ones with 255's (245's for the Camaro are still widely available). Know your limitations as far as working on them, you will go broke paying someone else to work on them if you plan on driving it alot (they are 25 years old). Having said all of that, they can be great cars and a lot of fun.

 

I was the same as you, had a C3 and added a C4. Do a lot of research and go look at some locally and figure out what you like in the different models/engines. While the basic body style stayed the same, every few years, GM tweeked the nose, tail or interiors. Same on the engines. Crossfire, L-98, LT1, LT4, or LT5 ZR1. Manual or auto? 4 speeds up to 89 or so, then the 6 speed. Wiring harness hacking evidence? Run..... too many sensors on these cars and expensive and time consuming to troubleshoot. While I was deployed I spent nights (when I could) cruising the internet learning and deciding what I liked and didnt like. Finally came home and spent another 3 months shopping around and found a low mileage car for a very good price. I have been very happy with my choice!

Good luck

 

You should know the major differences between the early C4 and late C4. Sounds like you've got a car picked out already and IMHO, that's a mistake. The early C4's 1985-1991(not counting 1984) came with the L98. Nothing wrong with it, just don't expect a lot after 4,500 RPM or so. Good torque on the bottom end, but not a lot of rev's or power after that (not bagging on them, we have one). Plan on getting a set of injectors if it hasn't been done to the early C4 yet. The factory injectors sucked and replacing them with the rebuilt FCI injectors, really woke up our early C4. Also, many early C4's definitely have a reputation for starting problems. Look at the tech section. Our early C4 has had extensive work there.

Late C4's came with the LT1, which is considerably faster and has a good deal more horsepower. There are things about the late C4's that can **** you off too. The door panels are a problem, as well as the power brake booster, heater core and heater door blend control. The replacement for the distributor was the Opti and this was prone to moisture, but most of that should've been fixed by now.

If the 87 Vert' has low miles, been babied, well taken care of and has had one owner, then by all means go for it, but look at the late C4's as well. You don't see many early C4 verts' any more and they are beautiful cars.

 

Lots of good advice here already, I will include a couple of links to purchase guides concerning C4's, good luck.

http://www.corvettephotographs.com/c...repurchase.htm

http://www.corvette-guru.com/uploads...uyersGuide.pdf

 

I have an 1985 Corvette with around 37,000 miles. I bought it because it was the color combo I wanted and it was too cheap to pass up. I have had it for three years and it has always started with no problem. It has never left me stranded. The worst problem I had/have is now the clutch is on the way out. I change the oil yearly no matter how many miles I drive it(only really drive it a couple of times a week when its nice). It is not the fastest car out there and it is true that as the years progressed the technology got better. However, I am not racing anyone or going to the track so the difference is not enough for me(stick a ZR1 in front me and maybe I change my mind). I also could care less about value down the road. Sure in 60 years it could be worth a lot of money if it is all stock with low miles. I would rather it look the way I want it too and drive it into the ground. It's more fun that way!

Some people say don't get an early C4, don't listen to them. Get the one that suits you, with the options and colors you want. My advice is find the Corvette that is taken care of the best. That is what makes the most difference, after that it is all luck. Good luck in your search, hope it works out for you.

 

I really appreciate the input from all! The links are great!
The car I will be looking at is an automatic. I do not have my heart set on it. I looked at a few already they were pretty beat up, wiring harness issues, starting, leaky injectors, cooling, bad body work. Now I have a better understanding of what not to step into!

 

From the Corvette Action Center

http://www.corvetteactioncenter.com/tech/buying.html

Good Luck!

 

I recommend that you shop for the latest-model-year C4 you can find that is in excellent condition. These cars were refined and improved every year they were built. You'll spend more to fix what's wrong with one than you'd have spent to buy one that's in great condition. Educate yourself before you buy, and shop carefully. These cars can be a joy to own and drive, or they can be a money pit and a nightmare to own. It all depends upon the specimen you select.

As a beginning guide, here is a list I generated when I was shopping for a C4. It does not include anything related to the ZR1, because I wasn’t in the market for a ZR1. It includes the items that I considered to be notable changes as the C4 evolved during its life cycle.

C4 Corvette Evolutionary Highlights:

1983: C4 was deemed not ready for delivery. No 1983 model year Corvettes sold to the public.

1984: C4 sales begin. It is a completely redesigned car, but used the Crossfire (throttle-body) Injected engine that appeared in 1982.

1985: Tuned-port-injected L98 is introduced as the new engine (thru 1991), rear axle on manual trans cars became Dana 44 (thru 1996)

1986: Convertible was re-introduced (all were Pace Car replicas), ABS became standard, VATS (Vehicle Anti-Theft System) introduced, all convertibles and late coupes had aluminum heads

1987: Roller lifters added

1988: Improved flow-thru ventilation in coupes, new dual-piston front brakes, E-brake used discs rather than separate small drums, 35th anniversary edition offered (coupe only), white with black roof bow & white leather seats (2050 units sold)

1989: ZF six-speed was new manual transmission

1990: Improvements to ABS and yaw control, radiator improved, instrument panel returned to analog except speedometer and fuel gauge, driver’s side airbag and glovebox added

1991: Rear exterior, nose, gill vent panels restyled, power steering cooler became standard

1992: LT1 introduced as standard engine (300 HP), traction control became standard, weatherstrips improved, insulation added to doors and transmission tunnel to reduce road noise

1993: Changes made to LT1 to cut engine noise (torque increased slightly), PKE introduced, 40th anniversary edition option for coupes and convertibles (all were ruby red exterior and interior)

1994: Sequential fuel injection and more powerful ignition introduced, passenger’s airbag added (glovebox deleted), all seats were leather and were redesigned with significant changes to side bolsters, run-flat tires optional, convertible rear window became glass with built-in defogger, A/C used R134A, electronic controls added to automatic transmissions, PCM used flash memory rather than EPROM.

1995: Indy Pace Car replica was convertible only with dark purple metallic and white (527 units sold), stronger French stitching used on sport seats, drip tube added to A-pillar weatherstrip to improve water sealing, fuel injectors revised to cut dripping after shutdown, connecting rods changed to powdered metal for strength and weight uniformity, larger J55 brakes used on earlier Z07 and ZR1 became standard, wiper arms changed to improve performance, newest ABS and ASR standard, gill vent panels restyled, actively-vented Optispark distributor on LT1 was an improvement over previous passively-vented units.

1996: LT4 engine used (only) on all 6-speed cars, LT1 was used with automatics, automatic transmissions were improved (clutches, bands, torque converter), Grand Sport option offered (admiral blue paint with stripes, LT4), Collector Edition available (silver paint only), new On Board Diagnostics (OBD-2), LT1 and LT4 had new throttle body.

Happy hunting!

Live well,

SJW