Quote:
Originally Posted by phoneman91
I made a promise back in 1960-that I would legally own a Corvette some day-no matter what.
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That line right there sounds like you finally got tired of driving stolen ones!
Quote:
Originally Posted by phoneman91
Finally ready to buy one. I need some advice and insight.
I am focused on a C5--2001 or later Convertible with manual transmission and Z51. Seems to be a very good buy now.
When were the high tension piston rings stalled? It is my understanding that the factory change occurred mid April 2001. Does anyone have an exact date?
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Here are the changes that were made to the 2001 - 2004 C5 during its production run:
2001
return to 28# injectors for all models.
Second Generation Active Handling
Nassau Blue discontinued
Alternator 'clutch' pulley added on A4 cars
New soundproofing + foam in all cars
Smaller keyfob
electrochromic dimming rearview and driver's mirrors
lighter AGM battery
Thickness + Material in vert change
Chrome exhaust tips for coupe + vert
85MM MAF with integral temp sensor (versus 74mm with separate plug for IAT)
LS1 cam profile changed to: .500/0.500, 198/208 on 115.5LSA (From: 0.472/0.479, 202/210 on 117)
All Corvettes now have the LS6 intake manifold
All Corvettes now have the LS6 engine block (windage passages in block), which includes a beefier oil pump.
LS1 changes result in new output of 350 HP @ 5200 RPM and 375 Ft Lbs of torque @ 4400 RPM (MN6)
Hardtop/FRC discontinued
Pup cats added to all models
Stronger synchros in all transmissions
Exhaust manifolds revised (5hp regained) - thin wall cast replacing SS manifolds
metal valvestem caps (late year)
Torque Tube changed from metal-matrix composite to aluminum alloy 6061, increased in dia from 55 to 63 mm.
Driveshaft couplings have also been upgraded on manual-equipped models for additional strength and durability
Introduction of the Z06, which has as differences:
hardtop body style
rear brake ducting
screened inlets on front fascia, without foglights
F1 supercar tires 265-17 front, 295-18 rear, on 17x9.5 and 18x10.5 (one inch wider, respectively
new LS6 top-end with new style head design (10.5:1 compression, 64cc chamber), LS6 cam (0.525/0.525, 204/211 on 116) - 385hp
M12 transmission with shorter gearing (1-2-3 analagous to MN6 with 3.90 rear diff
Titanium exhaust system
lightweight windshield
New, stronger clutch with redesigned master + slave cylinder
Stronger rear differential (shotpeened ring gear)
Red brake calipers (otherwise identical)
Trans overtemp warning light on DIC
6500 redline gauges with special checkering + Z06 font
redesigned PCV system to help combat oil burning
Red LS6 Fuel Rail Covers (FRC's)
FE4 Z06 suspension - uprated springs, bars (30mm/23.6mm), shocks (note front spring and rear bar same as Z51)
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2002
Z06 Changes:
Z06 LS6 cam changed to: 0.551/0.547, 204/218 on 117.5
Less restrictive intake airbox lid
Descreened MAF
Removal of pup-cats (total with changes = 405hp)
Z06 shocks revised with less rebound for better launching
Z06 brake pads revised for better stopping (generate more dust)
Lighter, sodium filled valves w/ stronger valvesprings
higher tension rings installed to prevent oil burning problems
slight piston redesign *
clutch strength upgraded.
HUD available on Z06 (not avail '01 model year)
Wheel supplier changed to Speedline, moved from forged to cast. Weight nearly identical
Electron Blue color offered
Steel endlinks changed to aluminum
Aluminum automatic transmission cooler case (all models)
AM/FM stereo with in-dash CD player now standard on Coupe and Convertible
AM/FM/Cassette only available with 12-disc CD changer on Coupe and Convertible
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2003
Late model-year new fuel system design from C6's
2003 anniversary edition with Anniversary paint and decal option.
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2004
Z06 shocks further refined. Accompanying upper front control arm bushing, and rear swaybar bushing changes.
2004 Commemorative Editions. CE Z06 comes with carbon fiber hood and has decal package.
Quote:
Originally Posted by phoneman91
Was the piston slap issue also corrected at the same time as the piston ring issue? I seem to remember that piston slap issue was corrected by the model year of 2002. Does anyone have the exact date of change of piston type and tighter fitting of the piston at the factory? Did this involve the LS1 also-or just the LS6? Will piston slap always be noticeable at cold start (ambient temperature in the 20s F)?
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I don't remember the piston slap issue ever being resolved with the LS1.
Quote:
Originally Posted by phoneman91
How can one determine the exact date of manufacture of one of these Corvettes? The driver's side door just has the month and year of manufacture.
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Remove the bumper off the car and pull the build sheet out of the front frame hollow space.
Quote:
Originally Posted by phoneman91
I have read about the oil pressure sensor issue and the difficulty of replacement . This is one of the first questions that I ask the owner-has the OPS been replaced?
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Who cares if it has been replaced, the question you need to ask is HOW it was replaced. Did the previous owner do the hack job and cut a hole in the firewall beneath the cowl or did they remove the plenum? The best way to fix that problem and make it a non-issue the next time it goes out (and it WILL go out again), is to relocate it the way I did mine
in this thread.
Quote:
Originally Posted by phoneman91
Does GM have a dealer database of all dealer maintenance done to a particular VIN? I know that Ford has such a database called Oasis. Is there a similar GM database ?
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Yes, but I can't remember if all dealerships share their databases. It's been so many years since I visited a dealer that I can't remember. I wouldn't let most of those hacks near my car.
Quote:
Originally Posted by phoneman91
I have asked that the Corvette be placed on an overhead lift so that the underneath can be checked. I will look for leakage from the output shafts and from anywhere else-especially from the back of the engine block-to make sure that the oil pressure sensor isn't leaking nor the camshaft position sensor.
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There's also the rear main that can leak and the plate on the back of the motor that can leak also (you can see the top of the plate just above the flywheel in this picture). Ask me how I know.
You have to drop the entire drivetrain from the torque tube to the rear suspension to fix that issue.
Quote:
Originally Posted by phoneman91
I will also check for headlight lift operation. And check for present or past battery leakage damage underneath the battery tray.
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You need to check the battery too. Not just any battery will work correctly in these cars. It needs to 78-6YR, 700 CCA, with 120 RC. The AC Delco battery number that meets these requirements is model number 19001632.
Quote:
Originally Posted by phoneman91
I am looking at a beautiful 2001 Convertible with 6 sp and Torch Red/Light Oak. Z51,N37,-almost all options. Three owner,35k miles-with new Optima.And four new Michelin Run Flat tires! Underneath the hood-all of the aluminum parts have no corrosion at all -even the front of the engine block. Nor are the heat shields on the exhaust headers old looking. I wonder if this Corvette ever saw rain.
It is amazing how nice many of these Corvettes are ! Most owners take extremely good care of them and the mileage is very low usually for a vehicle of this vintage.
Any advice?
Appreciate any help.
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Have you checked the date code on those tires? They may look new but you will never know until you check the date code.
Here's how.
Good luck with your purchase and welcome to the forum. You should jump into the intro forum and introduce yourself to the masses.