Performance numbers

[Joe C.]

Re: Performance numbers

I've checked several sources, including various web sites. I cannot find reliable information regarding performance figures for my car. I have a 1969 with a 427/400 hp 4 speed (no air cond.) and a 3.36 rear end. Does anyone know what this car is suppose to do 0 - 60 and in the quarter mile, and top end? I also know that if the numbers are based on the stock tires from 1969, the times will be bad. Is there any information that shows what the car should be able to do while using newer radial tires?

Anthony,

I see that the thread is getting a bit sidetracked, but 1/4 mile performance is extremely subjective, and dependent on a huge number of variables, some of which are: vehicle's GROSS weight (including fat driver), elevation, ambient humidity, ambient temp, prevailing winds, friction coefficient of track surface, even lane choice influences friction coefficients, as does time of day, and overcast/sunny conditions. Did you ever see any 1/4 mile comparisons specifying that all of the above factors were equalized? How about even three or four of them? Hell, the most important factor in 1/4 mile times/top speed is transmission/axle ratios.

I remember, when the all-new Corvette came out in 1984............this was, at the time, considered a benchmark year, and a hopeful time marking the renaissance of the Corvette as a high performance vehicle. Not too long after the L98 made its debut in 1985, with its much improved pefrormance, Car & Driver Magazine did a comparison test of a 1986 Corvette versus a 1968 L88 Corvette. Don Sherman was the technical editor at the time, and IIRC, it was not a very scientific test. The 1986 pulled a HUGE holeshot on the L88 due to traction, held an enormous lead with its prodigious torque and the advantageous gearing with the 700R4. By about 1/8 mile, the L88 gathered "steam", narrowed the gap, and then came on like an express train. The E.T's were very close, with the L88 ahead by maybe .1 sec. The top speeds, however, were a different story. The L98 went through the traps at about 96 mph, while the L88 recorded close to 110 mph!

Joe

[Joe C.]

Re: Performance numbers

Hi Joe

I should have posted links to these Michigan events.

www.fastraces.org

www.geocities.com/psmcdr

My post was in reference to the performance of the stock tires that these groups require. For example, a '69 L88 on stock tires ran 11.75@122 in 2005 at the PSMCDR. In 2005, C&D ran an '06 Z06 at 11.7@125 on the production tire. Both cars are high HP and very dependent on tire for their e.t. I was surprised at how fast the bias tires were. The cornering performance is not this close!

Bill

Bill,

Here is a link to another sanctioning body, based in NJ. Raceway Park, Englishtown NJ is its "home" track:

http://www.stockappearingdrags.com/home.asp

"Stock appearing" cars can use low friction race rings and bearings, special pistons with short skirts, which will cut internal friction dramatically, and can boost horsepower by 30-40 percent! "Do not try this at home", though! Those engines require frequent teardown/overhaul. They also take advantage of 90/10 front shocks, and now, adjustable ratios are widely used. Most important, super sticky DRAG RADIALS are legal............so long as the aspect ratio/diameter is comparable to stock sizes.

Joe

[Joe C.]

Re: Performance numbers

I guess the stock class I ran back in the late 50's and early 60's would equate to "Pure Stock" now. We were, however, allowed .060" over bore, balance and blueprinting, but no porting/polishing of heads, etc. The method of enforcement was by "Protest". The opponent had to put up $25.00 for a tear down. I made it to near the end of the season before I got caught (so to speak). Everyone was cheating and we all knew each other, but once an outsider comes in all bets are off. With me we never got past the removal of the dual quad intake where my matched ports were questioned. I had sand blasted them to remove any grind marks, but they still looked too good a match with the intake gasket. What they never knew was I had a .030" reground off-center crank and special pistons to compensate at about 12 to 1 compression. I had my carbs stacked up 1-1/4" w/ cross cuts to eliminate the deficiency in the Corvette manifold to cylinders 2 and 6. On payoff runs (money) for top speed, I used a set of Caddy El Dorado WCFB quads w/1-1/8" Venturies (all 4) and both primaries linked together (2 stage progressive instead of 3) so we had the torque to start in 2nd gear instead of first. With this combo I could usually hit 108 or better mph, but the ET fell off a few tenths. I like to think we were some of the pioneers of weight transfer too. Had the rear way down and the front jacked up with worn out front shocks! All went well until the day I got protested we dropped the driveshaft out going thru the quarter (messy). That was the end of my season (and career) and I went in the Army shortly thereafter.

Stu Fox

Pure stockers are permitted maximum safe overbore allowed for block design, which is generally .060" for Gen I SBC.

I'd rather concentrate all of my efforts into developing the most power out of a stock appearing, NON STROKER engine, rather than trying to figure out the best way to cheat.

I agree fully with the entire concept of the "stock appearing" cars, except for the fact that STROKERS are allowed. This is a HUGE advantage. Racers running bored/non stroked engines stand very little chance of winning "bragging rights" in the "stock appearing" division.

Joe

[Anthony L.]

Re: Performance numbers

Wow, I got more than I bargained for. Thanks to all those who replied. The comments by Bill on 6/23 at 6 a.m. were what I was really looking for. I had hoped to get information from Road and Track or Motor Trend, or some other such source. The information was not only the type I was looking for, but also relatively encouraging as compared to some other info. I've seen. Having said that, I also recognize that as Joe later said, there are a large number of variables, and any such info. is only an example, and should not be used as gospel for another similarly equiped car on another day and under different conditions. Thanks for all the help, guys!

[Bill M.]

Re: Performance numbers

I also recognize that as Joe later said, there are a large number of variables, and any such info. is only an example, and should not be used as gospel for another similarly equiped car on another day and under different conditions. Thanks for all the help, guys!

I'm don't know what C&D was doing in 1968, but I remember reading that they now correct their raw data to standard conditions so you can reliably compare the corrected data.