A: GM built 1,000 limited edition Grand Sports for the 1996 model run... 810 coupes and 190 convertibles. GM records indicate that of these, 976 Domestic (US), 13 Canadian, and 11 European exports were produced. Only one convertible is believed to have been exported to Europe and all exports were believed to have black interior. Click here for more detailed production information.
2. Q: What is the significance of the the red hashmarks on the front left fender of the Grand Sports?
A: During some races of the original 1963 Grand Sports, the teams placed strips of tape (rumor says duct tape) on the fenders instead of numbers to identify the cars.
3. Q: I need touch up paint for my Grand Sport but my dealer doesn't have a listing for Admiral Blue.
A: GM marketed the Grand Sport's brilliant blue paint as "Admiral Blue" (also available as a regular production option in 1995) but touch up paint is cataloged as "Cloissonne". The GM part numbers shown below are for the small bottles of touch up paint with the brush in the cap are:
4. Q: What are the transmission ratios in the various gears of my ZF 6-speed?
A: First through sixth ratios in the 1996 ZF 6-speed are: 2.68, 1.80, 1.31, 1.00, 0.75, 0.50. Reverse is 2.42.
Note: Another source lists ratios on some earlier ZF transmissions as: 2.64, 1.78, 1.30, 1.00, 0.74, 0.49, R:2.42 but this has not been confirmed.
5. Q: How do I calculate the effects on MPH and RPM if I should change my rear axle ratio or tire sizes?
Try using this handy online calculator at http://www.angelfire.com/fl/procrastination/rear.html. Surprisingly, due to the 50% reduction afforded by the ZF's 6th gear, 70 MPH in a Grand Sport equipped with a 4.10 rear axle ratio is only spinning the motor at 1950 RPM. And that leaves *plenty* of run for the top end!
6. Q: How much rear wheel horsepower and torque does a bone stock Grand Sport (LT4) produce?
A: Results will naturally vary from car to car, but one dyno expert (Vinci Hi-Performance in Orlando, FL) reports that most pure stock LT4's in good operating condition generate between 292 and 300 rear wheel hp (343 - 353 net HP) and about 300 lb/ft torque. Most "experts" concur that GM conservatively rated the LT4 at 330 net HP, perhaps because they didn't want it to eclipse the new C5 motor, the LS1, which was rated at 345 net HP. Ah, GM marketing is a strange and mysterious animal, indeed.
7. Q: How fast is a stock 1996 Grand Sport Corvette?
A: Kinda depends on what you mean by "fast." As usual YMMV (Your Mileage May Vary) but its been reported that a top speed of 172 MPH and a 1/4 mile ET of 12.93 have been recorded on "supposedly" pure stock Grand Sports. Can't verify that, but there is no doubt that most will run at least 165 MPH (in 5th gear, not 6th, interestingly enough) and turn the 1/4 in 13.5 or so. Modifed cars are an entirely different matter, of course!
8. Q: I've heard that all Grand Sports started out as white Corvettes. Is this true?
A: In a word, "no." This is another favorite old wives tale that insists that when GM was producing the Grand Sport, they started off with an Arctic White Corvette, then masked it off and painted the non-stripe areas Admiral Blue. There is an off white, primer base below the blue but its not an Arctic White finish coat. The rumor was probably started by someone who ran their fingernail over the pinstripes on a GS and noted that it caught on the blue, not the white, hence they assumed (incorrectly) that the blue paint was applied over white. The secret is that the pinstripes are not paint at all but rather tape with two paralell colors, white and blue. GM used tape for the pinstripes (and hashmarks) because they found it too difficult to paint. Understandable since the "skunk" stripe varies in width from front to back.
9. Q: Why do some people refer to Grand Sports as "Skunks?"
A: Are you blind??? And besides, only Grand Sport OWNERS are allowed to call them Skunks! :)
10. Q: What is the size of the stock throttle body opening on a GS?
A: The LT4 uses the same size throttle body as does the 92-96 LT1, that being 48mm. The intake manifold TB ports are sized at 52mm (go figure), making aftermarket 52mm throttle bodies a popular bolt-on performance item. Note: The larger 58mm throttle bodies are generally not recommended unless the engine has received extensive internal modifications. Bolting such a large TB on an otherwise stock engine could actually cost horsespower rather than add to it!
11. Q: What are the GM part numbers for Grand Sport wheels?
GM has superceded the part numbers on GS and ZR-1 5-spoke wheels:
12361446 changed to 9592480 on 01/02/00 17x11 black grandsport
12361447 changed to 9592379 on 01/09/00 17X9.5 black grandsport
12361448 changed to 9592377 on 01/08/00 17X8.5 black grandsport
12512904 changed to 10214047 on 01/08/00 17x11 bright silver ZR1
12512905 changed to 10214046 on 01/05/99 17X9.5 bright silver ZR1
The GS black center caps are Part # 9592388
12. Q: What is the GM part number for the Grand Sport Hashmarks decal & its dimensions?
The GM part number is 10279781, listed at "STRIPE, F/FDR WHL OPG" and each stripe is slightly different. The left (front most) stripe is 2-13/16" wide while the right (rear most) is 2-11/16" wide. Each is approximately 8-7/8" long and they are spaced 3/4" apart. Torch Red is a perfect match in color.
13. Q: What are the GM part numbers for the Grand Sport pinstripes?
GS pinstripes are actually 2 colors, Arctic White and Admiral Blue, on a single decal. These tape stripes made it a lot easier at the Assembly Plant to lay down perfectly parallel stripes. Note that some decals are specific to either coupe or convertible. Also be advised that these decals are becoming increasingly difficult to find as many have been discontinued. The OEM supplier for these decals, Kay Automotive Graphics, has supposedly been licensed by GM to start producing them again but as of this writing (March 2003) it is unknown when they will be available again. I wouldn't hold your breath. The GM part numbers and retail price (for those still available) are:
14. Q: What are the dimensions of the Grand Sport pinstripes?
The factory 2-color decal pinstripes are 1/4" wide (white) and 1/4" (blue) measured out from the wide center stripe. Actually, they are just a tiny bit narrower than this, but 1/4" is plenty close enough. From the front of the car going back, measuring across the wide center stripe only (not including the pinstripes):
15. Q: What are the GM part numbers for the Grand Sport emblems?
16. Q: Where can I buy a replacement Owners Manual and Video?
You can frequently find 96 Owners Manuals on eBay, or you can buy them from Helm, the OEM supplier, at www.helmdirect.com. Manual alone is $20, manual + video is $60.
17. Q: How can I get a copy of the original Window Sticker and Build Sheet?
Duplicate window stickers and build sheets may be ordered from the National Corvette Museum at www.corvettemuseum.com. NCM Members get a discount. You ARE a NCM member, right? ;-)
17. Q: Does the LT4 have a factory rev-limiter? If so, how does it work and what is it set at?
Yes, the LT4 comes factory equipped with an engine rev-limiter that functions by temporarily cutting off the fuel flow at a pre-set RPM. The stock setting is 6411 rpm. The "resume" rpm after fuel cutoff is 6397 rpm (at which point fuel starts flowing again). While effective, the rev-limiter can be quite disconcerting and somewhat violent, especially if you "bounce off it" in the middle of a high speed shift. Those that install a higher lift, higher revving camshaft, suggest reprogramming the PCM to move the rev-limiter up a bit, to 6800 RPM or so. Doing so will get it out of your way while still providing some level of protection for your your engine from excessive over revving.