How fast will a C3 go?
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
MY only comment is.....get a Garmin, do NOT believe any of them sites with tire/rpm/speed calculations....
something is rong with them, the cars are not going what your speedometers say they are....
my speedo is dead nutz on up to 75 mph....80 is really only 78, 100 is really only 94, that was fast as I got that day due to traffic....outta room....
by calculations when I thought I was doing 150 mph, in fact it was only about 130....btw, the car was hanging better than I was....
steering was fine....
I have also proven that the lift is ALL before the radiator, NONE from behind the radiator/under the hood in the engine compartment.....yard tests prove that.....I would THINK air would go through the radiator and not have a issue....rong, it's forcing up on the hood very hard in that first 12" or so of length...and obviously under the lights/cowling also...
something is rong with them, the cars are not going what your speedometers say they are....
my speedo is dead nutz on up to 75 mph....80 is really only 78, 100 is really only 94, that was fast as I got that day due to traffic....outta room....
by calculations when I thought I was doing 150 mph, in fact it was only about 130....btw, the car was hanging better than I was....
steering was fine....
I have also proven that the lift is ALL before the radiator, NONE from behind the radiator/under the hood in the engine compartment.....yard tests prove that.....I would THINK air would go through the radiator and not have a issue....rong, it's forcing up on the hood very hard in that first 12" or so of length...and obviously under the lights/cowling also...
Le Mans Master
Joined: Oct 2000
Posts: 6,209
Likes: 33
From: Texas-out west
all about aerodynamics and gordonm is right on, NO STOCK CORVETTE HAS EVER GONE 200 except maybe a new ZR!...you are dreaming as many do when they use any calculation to get a top speed. it will take more than a mile and if you don't think so I am sorry to say you have no clue, been 140 in a 70 LT-1 and front was up bad, beenf 155 in 67 435 coupe and front was up really really bad, been 140 in 03 zo6 and was very stable, friends been to 170 in c5 Zs no problem but took over mile to get to speed, not my opinions but real world facts, go check out texas mile and see for yourself what it takes to hit 200mph...very few do it.
Advanced
Joined: Aug 2009
Posts: 53
Likes: 0
I'm not really to sure about the 200 mph thing out of a C3. Aerodynamic forces are equal to the square of the speed. So everytime you double your speed, the force pushing against the car goes up by a factor of 4.
I could believe 160 or so, but getting to 200 with a fairly stock C3 setup seems unlikely to me.
I could believe 160 or so, but getting to 200 with a fairly stock C3 setup seems unlikely to me.
Le Mans Master
Joined: Aug 2000
Posts: 9,341
Likes: 0
From: Las Vegas Nevada
Pro
Joined: Nov 2004
Posts: 575
Likes: 0
From: Nice Lake Ontario
I have an old vette mag somewhere in my boxes 
that tested a stockish L-88 in 1968-9 that run 185mph & I believe that was with 3.08s & a turbo 400.
I just had my 69BB up to 115 mph or so (indicated) the other night at about 5,000rpm, that's with 255x60x15s & 3.36 gears. Far as this old guy was willing to trust them old suspension parts...did seem pretty solid on the road thou.
My old 74 back in the day ran an indicated 143-145 mph with stock gears, turbo 400 & the original 350ci with upgraded 350hp heads, cam, intake & headers at about 5,500rpm.
that tested a stockish L-88 in 1968-9 that run 185mph & I believe that was with 3.08s & a turbo 400.I just had my 69BB up to 115 mph or so (indicated) the other night at about 5,000rpm, that's with 255x60x15s & 3.36 gears. Far as this old guy was willing to trust them old suspension parts...did seem pretty solid on the road thou.
My old 74 back in the day ran an indicated 143-145 mph with stock gears, turbo 400 & the original 350ci with upgraded 350hp heads, cam, intake & headers at about 5,500rpm.
Safety Car
Joined: Nov 2005
Posts: 3,961
Likes: 573
From: Lompoc, CA. Santa Barbara County
This thread is back!? I took my brand new 79 to 141 mph when new. I installed an onboard computer called Compuserve. You placed four magnets on your driveshaft, and calibrated the speedometer function using mile markers. It blinked 139 a few times, and I refused to lift until I saw 140, then it blinked 141, and I lifted. That was before the 700R4 tranny swap and the heads, headers, exhaust, intake, fi, and suspension and brake mods. I had it up to 140 recently, but with my bumper mods, the headlight popped up on me. I hope to join the 150mph club someday, and live to tell about it. It's amazing the speeds the drag racers attain in only 1/4 mile.
Bee Jay
Bee Jay
Racer
Joined: Nov 2008
Posts: 326
Likes: 0
Ah quit laughing. We can't help the fact that California car ***** ruined the go fast cars with so much smog junk that we are very limited to 190hp.
I still think the 80/81/82 Vettes are the second best looking Vettes.
We're not even allowed to drop in a high hp engine or modify what we have.
For $8,000 I have an extremely good looking car that put the Camaro's and any Mustang to shame in the looks department.
I never ever go anywhere that somebody doesn't say "nice f-ing car).
It is the most fun car to drive I've ever had and I've had allot of nice cars in my 41 years of driving.
I am retired but I treat my 81 like it's a ZR1 because I don't have $100,000+.
I can bend the needle on my 85 mile speedo and that enough for a
28 year old stock car and be safe.
I still think the 80/81/82 Vettes are the second best looking Vettes.
We're not even allowed to drop in a high hp engine or modify what we have.
For $8,000 I have an extremely good looking car that put the Camaro's and any Mustang to shame in the looks department.
I never ever go anywhere that somebody doesn't say "nice f-ing car).
It is the most fun car to drive I've ever had and I've had allot of nice cars in my 41 years of driving.
I am retired but I treat my 81 like it's a ZR1 because I don't have $100,000+.
I can bend the needle on my 85 mile speedo and that enough for a
28 year old stock car and be safe.
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Verdad Gallardo
Pro
Joined: Sep 2002
Posts: 624
Likes: 1
From: Melbourne, Fla. 6 months- New Middletown, Ohio 6 months
The question is, really how much actual HP does it take to get 200 out of the 3 basic body styles of shark??? 68-72, 73-77, and 78-82??? I willing to bet the 68-72 takes less than the others....
and it take maybe 120 hp to push a shark to 100 mph, and only 350 to run 200mph.....even the sharks with the super lo performance engines could easy to 120-140 so the above quote is way off in the calculations.....He got the concept of square law ok, but the initial numbers are way lo....
NOW, in saying the above, I did not say it would get there pulling like a F15 or something....but it's going to take way less than a mile.....maybe 1/2 mile at most....
and it take maybe 120 hp to push a shark to 100 mph, and only 350 to run 200mph.....even the sharks with the super lo performance engines could easy to 120-140 so the above quote is way off in the calculations.....He got the concept of square law ok, but the initial numbers are way lo....
NOW, in saying the above, I did not say it would get there pulling like a F15 or something....but it's going to take way less than a mile.....maybe 1/2 mile at most....
Melting Slicks
Joined: Feb 2003
Posts: 3,053
Likes: 4
St. Jude Donor '03,'11
Tech Contributor
Joined: Jun 2004
Posts: 20,910
Likes: 962
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
....
I have also proven that the lift is ALL before the radiator, NONE from behind the radiator/under the hood in the engine compartment.....yard tests prove that.....I would THINK air would go through the radiator and not have a issue....rong, it's forcing up on the hood very hard in that first 12" or so of length...and obviously under the lights/cowling also...
I have also proven that the lift is ALL before the radiator, NONE from behind the radiator/under the hood in the engine compartment.....yard tests prove that.....I would THINK air would go through the radiator and not have a issue....rong, it's forcing up on the hood very hard in that first 12" or so of length...and obviously under the lights/cowling also...
I am curious if eliminating the "bottom feeder" portion of the air intake would provide more lower surface area to balance out the upper/lower pressure forces, possibly reducing the front end lift. Sounds like an interesting experiment down the road.
Drifting
Joined: Oct 2005
Posts: 1,528
Likes: 148
From: East London/SW Essex UK
Well, it's due to the inherent function of this space and volume. The 12 to 15 inches ahead of the radiator is a diffuser. It takes the high velocity air coming through the grill and undergrill holes and converts it to a slow moving, "high" pressure area, which is more efficent regarding getting air to flow more equally through all the radiator fins.
I am curious if eliminating the "bottom feeder" portion of the air intake would provide more lower surface area to balance out the upper/lower pressure forces, possibly reducing the front end lift. Sounds like an interesting experiment down the road.
I am curious if eliminating the "bottom feeder" portion of the air intake would provide more lower surface area to balance out the upper/lower pressure forces, possibly reducing the front end lift. Sounds like an interesting experiment down the road.
Last edited by roscobbc; Sep 7, 2009 at 05:21 PM. Reason: spell
Tech Contributor
Joined: Jun 2004
Posts: 20,910
Likes: 962
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Do you apparently hang out with a crowd who are too brain dead to occasionally monitor the gauges while running down the road?
I'm an automotive design engineer. I always have instrumentation data available to me while I do work on any car. Even my street car.
Now, would you care to rephrase your comment above?
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
at any rate, TV, I AM smarter than some phd's.....
at least I know NOW to ground a nuclear power plant....who'd a thunk...eh???
Intermediate
Joined: Nov 2005
Posts: 38
Likes: 0
Here is my 2 cents worth. I have run a 73 C-3 with a ZZ3 at Road America and hit 135 before I had to turn. I do have rack and pinion steering becuase at that speed the old syetem, which was in great shape, was very dicey to steer. So, if you are going to do this, upgrade the steering - get ride of the power steering for sure. I also have coil over's front and lowered the front significantly from stock and that helped as well.
Run with tops on, windows up if legal - you need all the aerodynamics you can get.
Aerodynamics are squared so 200mph stone stock would be a challenge. Here is a reference points - what does a C-6 Z-06 run stock - that car is a whole lot slippyere than a C-3.
Run with tops on, windows up if legal - you need all the aerodynamics you can get.
Aerodynamics are squared so 200mph stone stock would be a challenge. Here is a reference points - what does a C-6 Z-06 run stock - that car is a whole lot slippyere than a C-3.
Drifting
Joined: Oct 2005
Posts: 1,528
Likes: 148
From: East London/SW Essex UK
Why would I need a spare engine? What's going to cook?
Do you apparently hang out with a crowd who are too brain dead to occasionally monitor the gauges while running down the road?
I'm an automotive design engineer. I always have instrumentation data available to me while I do work on any car. Even my street car.
Now, would you care to rephrase your comment above?
Do you apparently hang out with a crowd who are too brain dead to occasionally monitor the gauges while running down the road?
I'm an automotive design engineer. I always have instrumentation data available to me while I do work on any car. Even my street car.
Now, would you care to rephrase your comment above?
- although I would guess that 'my crowd (and anyone else) who are too brain dead to occasionally monitor the gauges' would have great difficulty doing just this, and managing to keep any car safely on the public highways IF actually ever getting the chance to drive anywhere close to the theoretical speeds we have all been discussing.
Pro
Joined: Jun 2004
Posts: 561
Likes: 1
From: No longer in Heaven
Great Analytics
For those of you who have looked at this thread about C3 top speed (and especially those who speculated that it was near 200 mph) take a look at this link from the Z06 forum. I own both a 427/435 '69 roadster and an '06 Z06, and always have felt the top speed of a C3 was nowhere near 200. I've only gotten the '69 to about 125 (scary) and the Z06 to 140 (not as scary).
The Z06 barely, theoretically, gets there (with 505 hp) and would need a ton of more HP to go much higher. I gotta believe the C3 top speed is well short of a buck seventy five. Maybe the speedo is right!
http://forums.corvetteforum.com/c6-z...each-gear.html
The Z06 barely, theoretically, gets there (with 505 hp) and would need a ton of more HP to go much higher. I gotta believe the C3 top speed is well short of a buck seventy five. Maybe the speedo is right!
http://forums.corvetteforum.com/c6-z...each-gear.html
