C4 less problems...

[KingCorvette]

So the C4 has a possible opti-spark problem.

The C5 has rocking seats, bad oil sending units, bad gas gauges,
leaking rear axles and battery leaks.

The C6 has rocking seats, popping tops, too many electric hang ups,
auto start, and electric door.

The C4 seems more trouble free...........

Long Live the C4!!!!!!!!!!!!!!

 

[air1jpg]

So the C4 has a possible opti-spark problem.

The C5 has rocking seats, bad oil sending units, bad gas gauges,
leaking rear axles and battery leaks.

The C6 has rocking seats, popping tops, too many electric hang ups,
auto start, and electric door.

The C4 seems more trouble free...........

Long Live the C4!!!!!!!!!!!!!!

Nice!...

 

[6 Shooter]

KC - Your back, glad to see ya having fun!

YEP - Missing a year of production, frame shutter and cracking targa tops are a few of my favorite C4 accomplishments. ​

L8TR - D

 

[vetteoz]

So the C4 has a possible opti-spark problem.

Buy one with a L98; problem solved Just have to live with 245Hp

 

[CLABORN1960]

YEP - Missing a year of production, frame shutter and cracking targa tops are a few of my favorite C4 accomplishments. ​

L8TR - D

By a solid top, problem solved? The frame thing... oh well.....

 

[gmjunkie]

I don't think C4's have any less problems than any other generation!!
They all have there quirks!!:L:L:L
But each generation they just get Better!!
I've driven each generation at least once, And I can attest,They "JUST GET BETTER"!!

 

[tonylong]

Buy one with a L98; problem solved Just have to live with 245Hp

I agree with the L98. The HP can be improved a lot if you want to spend about $2,500 replacing the intake, heads and exhaust. Maybe I will one day.

 

[So Bay Vetter]

By far I think the biggest P I T A on a late C4 is the optispark just cuz it's so damned involved to replace (been there done that) and, as with any sports car or hot rod; there's fewer repairs if they're garaged. I read somewhere that the C5 had 1500 less parts than the C4; Love my 96 but it would be great to have less parts in the way when I wrenchin' . . .

 

[G Winter]

By far I think the biggest P I T A on a late C4 is the optispark just cuz it's so damned involved to replace (been there done that) and, as with any sports car or hot rod; there's fewer repairs if they're garaged. I read somewhere that the C5 had 1500 less parts than the C4; Love my 96 but it would be great to have less parts in the way when I wrenchin' . . .

Just because it had less screws, so it falls apart quicker.:joke

Glenn

 

[nelson84]

The biggest problem is the price. C4 vettes range anywhere from $3000 to $8000. What does a New C6 go for? I don't even want to know.

Other problem with the C6 the head lights don't flip up?????????

 

[Racer86y]

Prices

I like the way headlights are on C4 though.They sure look great

 

[Zo6 LVR]

Not uncommon to see late C4s going for $15-17. And if those breasts belong to your wife, you are a lucky man!

 

[Rogue]

I agree with the L98. The HP can be improved a lot if you want to spend about $2,500 replacing the intake, heads and exhaust. Maybe I will one day.

You will need about twice that amount. I did a cost analysis in a spreadsheet and this is what I came up with. The numbers after each item is the purchase price

Powertrain Purchased Cost

Heated Oxygen Sensor (3-wire) 70
TPIS Long Tube Headers 725
TPIS Y-Pipe 125
TPIS Catalytic Converter 220
TPIS Big Mouth Lower Plenum 425
TPIS Large Tube Runners 425
TPIS 52mm Throttle Body 280
Mid-America Smooth Intake Tube 50
Fuel Pressure Regulator 70
TPIS ZZ-9 Roller Rocker Camshaft 375
TPIS Valve Springs to go with New Cam 125
Cloys True Timing Chain/Sprocket 95
AFR Cylinder Heads with valves 1,500
TPiS Level 4 Chip 495
Accel Ignition Wires(8.8 mm)Accel Super Coil & Cutaway Distributor Cover 133
Accel Distributor Cap & Rotor 40
Labor ????

 

[Ugolino]

I always loved c4s, i owned 3 of them (and spent many, many weekends repairing them), but my c6 has been virtually trouble-free.

 

[photopod]

So Rouge, help me out here (as a newbie). Are these expenses "have-to's" to keep it running or are they "want-to's" to get the most out of it?

 

[Tuna]

I've had 3 C4s in my garage also. Great cars but not glitch proof.
My C4 experience is all late versions - 92, 93, 96.

OptiSpark on 92-96 thoughts:
My '92 was an early production LT1 and it had the OptiSpark recall. In fact it left me stranded 2 months into ownership when the first one failed. Then the recall replaced that one. The third one lasted about 100k miles and was still going strong. The early '92 recall aside, the OptiSpark worked just fine for me. The deal with the OptiSpark is to not get it wet especially if the engine is hot cause that cools the Opti and it sucks water into the vent and shorts it out.

Never had any problems with the Optis on the '93 or the '96. So, the OptiSpark 'problem' is less problem than you think.

C5s and C6s have totally different systems.

Some age and wear and tear issues to be considered on the C4:::

Battery:
The side post batteries in the C4 could be overtightened, thus causing an acid leak that got on the cruise control hoses and the wires below the battery. This could also eat at the frame, the fender panel and rocker panel.

C5 has a similar issue if the battery leaks.

Headlights motors:
In the late C4s, the bushings inside the gear cases would crumble leaving nothing but mush which doesn't open the head lights worth a crap. The bushings are cheap but the replacement work can be a pain. They seem to last about 8 years. Early C4s have problems with the gears.

C5 has motor/gear problems also. C6 - nada.

Wheel Hub bearings:
These last about 90-100K miles and then need replacing.

C5/6 - no clue yet.

Weatherstriping:
The C4 weatherstriping around all the glass will be going bad by now if not already replaced. They ain't cheap nor easy to replace.

I loved my C4s but I'm really in love with the C6. I'm glad I can afford to have 2 in the garage.
Btw, I've had to deal with the roof issues and rear end noise on my '06 and with clutch failure on my '08. Oh well. The keyless start only caused me problems once.

 

[Rogue]

So Rouge, help me out here (as a newbie). Are these expenses "have-to's" to keep it running or are they "want-to's" to get the most out of it?

They are most definitely WANTS.

The goal was to get about 75 bhp out of the stock L98 without rebuilding the whole engine and putting a stroker in it.

It was going to be $10k with labor to put a ZZ4 motor in it.

 

[photopod]

They are most definitely WANTS.

The goal was to get about 75 bhp out of the stock L98 without rebuilding the whole engine and putting a stroker in it.

It was going to be $10k with labor to put a ZZ4 motor in it.

Oh, OK, that's cool. Thanks for the help.

 

[tonylong]

You will need about twice that amount. I did a cost analysis in a spreadsheet and this is what I came up with. The numbers after each item is the purchase price

Powertrain Purchased Cost

Heated Oxygen Sensor (3-wire) 70
TPIS Long Tube Headers 725
TPIS Y-Pipe 125
TPIS Catalytic Converter 220
TPIS Big Mouth Lower Plenum 425
TPIS Large Tube Runners 425
TPIS 52mm Throttle Body 280
Mid-America Smooth Intake Tube 50
Fuel Pressure Regulator 70
TPIS ZZ-9 Roller Rocker Camshaft 375
TPIS Valve Springs to go with New Cam 125
Cloys True Timing Chain/Sprocket 95
AFR Cylinder Heads with valves 1,500
TPiS Level 4 Chip 495
Accel Ignition Wires(8.8 mm)Accel Super Coil & Cutaway Distributor Cover 133
Accel Distributor Cap & Rotor 40
Labor ????

Thanks for the details, this is exactly what I've been thinking of.
I'm going to import this to an Excel Sheet.

Any thoughts on what HP/Torque to expect from this?

 

[Rogue]

Check out this website for great information on how to get more performance from your C4 Corvette. Mod Advice for L98 and LT1s

Here is the website for TPIS: TPiS

Here is a great article from Super Chevy on how to make the L98 produce lots more power: Stealth TPI Induction - L98 Stroker Installation - Super Chevy Magazine
In the article, they started with an L98 without accessories, but with a camshaft, long tube headers, and a custom computer tune, it produced 327 hp (not rwhp).

A stock L98 produces about 220 rwhp (based on another article I read in CORVETTE magazine). With free flowing intake open top air filter, cat back Billy Boat exhaust, adjustable fuel pressure regulator, a Superchips ECU upgrade, it produced 250 rwhp. So it gained 30 with all those mods. If you add in the AFR cylinder heads, TPIS 50-state Legal camshaft, long tube headers, larger bore intake mods, and another tune using a new chip for the ECU to take advantage of all these mods, you should see about 300-320 rwhp. This is BEFORE any stroker is installed and using only the stock bottom end. Maybe someone who has actually done all these mods will know the true result. I think it is reasonable to expect that.

All those mods are based on all the magazine information that I have gathered.