I remember reading about that car a long long time ago.
No way

 

On C2s this is how you get the super duper power stearing option with your manual stearing car without having to shell out any extra money.

 

Gkull.... you mean 'get there quicker'?

 

I read a lot of these posts and to summarize.....

In a C3 to go 145 you really need a front spoiler.

I'm running 335hp in my 75 new 460# springs

I have 255/45/17s so at least I have the tires and engine for it.

Ralph

 

Most I ever did with my '76 was 120 on the straight after the Oak Tree turn at VIR and it was still accelerating up when I crested the rise and had to let off to prepare for the next turn on the course. Just a stock 76 s.b. with true duals and faster timing. I was pleased and the car held the ground fine at 100-120. I calculated once that with the 3:36 rear end, tires and max rpm of the engine the most I could do with that set up with 255 x 60 x r15 tires was between 135 and 138 but at my age, 68, I really don't think I have the reflexes for those speeds any more if I ever did. It would be so tempting to go into the block and cam it up a little, new heads, new intake and roller tappets and get the h.p. up to 350 or so and let it scream but the truth probably is that I can have all the fun I can handle with it on the twisty highways as is. Once I was doing 105 on state route 58 in Va. which is a great straight, not heavily traveled divided highway when I realized I was going 50mph over and at 20 mph over here it's reckless driving. I was going to go away for a loooong time and let off. Two miles later there was three state guys sitting there running a radar trap! That was, by the way, driving the car to the track in May to run it on VIR! A hoot and a half though. Can't imagine was 500 hp in a Zo6 would be or 638 in a ZR1 would be.....awsome comes to mind.

Lance P.

 

I did mean higher MPH. When I was figuring out top speed driving in my Vette because of an OD tranny I did all the math and 4.11 with my OD would have a peak HP at or near a MPH that I was looking for.

I go to the Bonneville Salt flats with people running their cars so I understand what it takes.

 

gkull...isn't it just math if the engine has enough torque and can run fast enough rpms to push the car at the last gear you have at the higher speeds you want? Max engine rpm plus rear end ratio driving wheels with tires of a certain circumference a calculated number of times per revolution or inches or feet of distance the wheel can travel of the engine through all those parts? It's how I calculated my stock s.b.'s max theoretical top speed though I've never tried to reach it..never had the opportunity. Just basic math plus or minus the engine's ability to do the work to actually do it.

Would be fun to drive the salt flats.

I wondered about my car if the engine would have the muscle to push the car to it's theoretical top end as the wind resistance would get a lot more so at the last 15 mph or so given a stock engine instead of somethine with hundreds of horsepower and ft lbs of torque. I know it will hit 120 easily 'cause I've done that on a road track but to see 138 mph with a stock s.b. I wonder if it would take a long, long road!

 

A few years a good friend of mine had a stock 69 convertible factory L-88 with Hooker header side pipes and no baffles. No radio, no heater, no power steering. That car was loud and strong for sure. I personally witnessed it pull to 7200 rpm in fourth gear and it was still pulling hard when he had to let off as we were running out of road fast. I drove the car myself one time and I have owned and driven some strong cars before but that was by far the most powerful car I have ever had the pleasure of riding in. It had a set of Ansen racing wheels and Goodyear blue streak racing tires and rode liked a wagon until the tires warmed up. The hair still stands up on the back of my neck just thinking about that car. What a ride.

 

I went 140MPH in my 77 and I didn't like it at all.
Things are real loud!!!

 

I ran mine on vir's 17 turn road track in May and once I found out how hard you have to push the engine, brakes to get around the track I realized I wasn't a race driver as I have a lifetime of driving smoothly and helping to make things last. I settled for 3/4 of the speed others drove, started last and improved my lap times and hit it hard on the straights but to race well, i.e., fast, you need to go around that track at very high rpms, go high and hard into turns with heavy, heavy braking going into them and keeping the rpms high as you go through the gearing required. In three sessions of 25 min's each I probably shifted the clutch something like 600 times though I sure didn't count. Everything happened at race speeds I was driving very, very fast and I was relatively slow.

Still, it was the dream of a lifetime to drive my own car on a road track once and I did it. I also learned I don't like pushing the car that hard nor am I tempermentally suited to be a race car driver. I think it might be fun to turn a few laps in my car on the NASCAR track here in Richmond at high speeds with the banked turns but have settled for zipping around an 85 mile drive on two twisty roads at 65 where the speed limit is 55 and I can go through 35-45 mph max corners at 65-75 and have a heck of a good ride.

I understand how you must have felt at 140. You aren't alone at the extremes for your car.

Lance P.

 

with every new bushing we go faster and faster.where will this end.i fear for our safety.i'll be out running the cops soon.

 

Maybe you should get some magnaflows

I've seen 140 a few times on my 77 trying to keep up with all the C5 C6's I run with ... didnt have time to look at the tach ....but it sure felt good..

 

If your speed is not proven on a GPS, you simply are NOT doing it...

the speedo's and tachs over indicate like MAD....

for instance, my '72 here is NOW dead accurate up to 70mph....

at 80 indicated, it's only 78 on the Garmin....at 100 ind, it's only 94 in reality....

does that tell you something??

tells ME that when the speedo says 150 it's only maybe 130 at most....

them tire/ratio sites are not worth a flip....they had my speedo over indicating by 15% or so at 50 mph.....and I ran the numbers many times....

 

I've pretty well glossed over this entire thread and can resist no longer. There is a LOT more to making a car go upwards of 200MPH than just stuffing a big enough motor into it to produce that kind of speed...the 'Sundowner' salt flats car was obviously very carefully engineered to look like a fairly unmolested C3 'at a glance' but just by looking closely at the picture I was able to pick up a couple things like exhausts exiting just behind the front wheels and a little metal strip running across the top of the windshield where it joins the T-Tops. I suspect what you can't see is even more telling, i.e., what's behind the grille (a HUGE source of drag on 'stock' C3's), what was done to smooth the belly, etc., etc.- I also saw it mentioned that it was powered by a "twin-turbo big-block' but not much beyond that...that could mean an all-aluminum 568" whopper intercooled with water-alcohol injection (2000HP??). That just scratches the surface of the HP vs. drag equation, but then what would you have to do to make the car [acceptably] safe to drive at those kinds of speeds? I have pushed my somewhat anemic 300HP '70 with completely unmodified suspension and brakes to about 110 a couple times and while the engine wasn't protesting in the least my butt-cheeks were telling my frontal lobe that I should discontinue this kind of behavior. My car's frame is in very good condition but a stock C3 frame is way too flexible and stock springing way too soft to safely attempt speeds north of around 150 without some kind of reinforcement, such as a 10-point cage that is tied into the frame as closely as possible to the front and rear suspension pickup points and VERY stiff suspension to go along with it. It's not the bumps that you feel at 75 that are cause for concern at 150+, it's the big waves in the road that you don't even feel at slower speeds that can bottom the suspension of an 'under-sprung' car and cause real mayhem. My vintage race Mustang has 700-lb. springs (yes-700 pounds/inch) in it and while it rides literally like a 1-ton truck at slow speeds it feels very safe north of 100 and goes exactly where it's pointed with very little drama. To give some historical perspective to all this, the closest that Chevrolet came to mounting a 'factory' effort back then at LeMans (Home of the 3.7 mile long Mulsanne straight) was with Jim Hall's Chaparral team in 1966 and '67. Hall's fiberglass-chassised, aluminum 427-powered '2F' prototype with a drag coefficient roughly 75% that of a C3 Vette and weighing 1000 lbs. less was able to get to about 205 down that straightaway. Ford's GT40 MkIV's were doing about 215 on the same (427") displacement with much slicker bodywork (no tall wings) than the Chaparrals. It also bears mentioning that speed on THAT straightaway was essential to winning at LeMans and Ford literally spent millions in 1960's $$$ to achieve it. To answer the OP's question, if you completely modify a C3 so that the body looks externally stock but has as much drag-inducing stuff blocked off or smoothed over as possible, then tie the frame together with a very beefy rollcage that makes it impossible for a passenger to get into, stuff it full of ridiculuosly bored, stroked, overboosted and intercooled big-block grenade power, then take it to the Bonneville pilgrimage every year and tune on it, you can get one to run about 240 MPH...for a couple miles. I don't know how much $$$ Gale Banks & Co. spent to do that, but I do know that for a little over 100k you can buy a shiny new ZR1 that STOPS at 205MPH when the governor kicks in, and it'll do that damn near all day with the AC on. Technology marches forward...

 

Oh, what I could do with a motor Like Steve's 542 ci tri power!

After entering the Silver State open road race in the 150 mph class where the top speed was 175 mph and I popped the motor during test runs. I changed the 79 vette into this new front end to handle higher speeds. I have QA-1 dual adjust coil overs with 600, 650 700 pound front springs and can adjust the nose way down.

Yes I have the plexy glass light covers. I broke the nose and this is just after I repaired it the august

5 speed and TKO 600 with 4.11 Tom's rear end is bad A$$ with a 434 ci roller after market block. I make the 3000 pound wet minimum weight for racing












Rear view with road racing slicks

 

Trying to even compare a mark 4 version of the GT 40s to a C3 no reason to mention it. The 427 it used was also in a mild state of tune even for its time so it could last for a 24 hour lemans race. If they could up the power not worry about 24 hour dependability 215 down the strait would have been nothing.

Bonneville is at i believe 4500 ft above sea level. They say a car that can do 200 at bonneville can do 225 at lower altitude.

I wish i was good at computers would put up a picture of a 53 studebaker that did 230 mph on gas at bonneville in 1960 with 1960 knowledge. Early 392 hemi stroked to 454 cu. front mounted supercharger. It also did 237 with a 20 percent mix of alcohol. Windsheild was not laid back but the top is chopped 8 inches. No mirrors and i'm sure it had a belly pan. But think about it thats the same as 255 on gas and 262 small amount of alcohol at close to sea level with the big wide frontal area of a 53 studebaker with 1960 knowledge of cars. 53 stude has a 120 inch wheel base nice for going in strait lines.

 

Actually that is not a true statement. The loss of HP is made up for by less air resistance. Land speed records are set at the highest practical elevations. Bonneville and the Black Rock desert on a hot day exceed 7000 feet ADA when they are going for records. They don't show up in cold November when the altitude is less than 3500 feet.

It is only in modern era fighter jets that have been able to break the speed of sound at low altitude. They can only haul A$$ at very high altitudes

 

 

Thanks GKull...while I didn't mention it in the original post, I was trying to illustrate how ridiculous some of these speed claims really were by using known data, i.e., if a GT40 MkIV could only do 215 at LeMans while weighing way less then and punching a much cleaner hole in the air than a C3 how much horsepower would it really take to push that brick (and C3's ARE bricks-pretty ones to be sure, but still bricks) through the air at the same speed? Again, not trying to offend anyone...just trying to put things in their proper perspective.