
Evolution of NASCAR technology
#1
Posted 24 January 2004 - 20:46
In the early days the cars were strickly stock – no modifications allowed, but over the years this state must have been altered. Modifications of engine, suspension, brakes, transmission, body work (welding of the doors, extension of the wheel arches and so on), with the mandatory tube-frame chassis’ from 1981 as the most radical shift (I can think of). When did roll cages get introduced?
I’m asking for some help on dates of the various technological changes. Thank you in advance for your answers.
Jesper O. Hansen
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#2
Posted 24 January 2004 - 21:46
Here is what was okay for 1950, from that year's Rule Book:
1. Complete bodies, hoods, fenders, bumpers, and grills.
2. Headlights removed or covered with masking tape.
3. Chrome protected by masking tape.
4. Windshield protected by celluloid or cellophane covering.
5. Rear seat cushion must be removed, front seat cushion must be intact and not altered.
6. Muffler must be removed.
7. Doors must be strapped shut.
8. Radiator dust screens permitted.
9. Any wheel or tire size permitted.
10. Only stock radiator and cooling system permitted.
11. Water pump impeller may be altered.
12. Transmission must be stock for model car used.
13. Differential must have stock catalogued gears for model used.
14. Locked rear ends not permitted.
15. Overdrive and two-speed rear axles permitted.
16. Complete motors must be in chassis and body as in catalog.
17. Bore may not exceed .003 oversize and stroke must be stock.
18. Valves, valve springs, cylinder heads, and manifolds must be stock.
19. T-3 Ford camshafts or altered camshafts not permitted.
20. Ignition must be stock.
21. Flywheels must be stock with no alterations.
22. Carburetor jets may be any size.
23. Shock absorbers may be adjusted or valves changed, no other changes permitted.
24. Any fuel and oil permitted.
25. Pickup in fuel tank may be moved to the right side.
26. Any type spark plugs permitted.
27. Self-starter must be in working order.
28. Removal of fan or fan belt or air cleaner not permitted.
No Jeeps, station wagons, or pickups permitted; recommended that wheels, hubs, steering parts, radius rods, and sway bars be reinforced and strengthen in any manner.
Roll bars and cages were there from the start, usually simple hoop-like affairs
Seatbelts were an early requirement as well, usually coming from aircraft.
#3
Posted 24 January 2004 - 22:13
-William
#4
Posted 25 January 2004 - 00:18
Originally posted by Don Capps
Actually, it was pretty gradual and subtle for awhile. "Stock" was defined as "meaning any part which is listed in the manufacturer's catalog for the year, model, and type car entered."
Roll bars and cages were there from the start, usually simple hoop-like affairs
Seatbelts were an early requirement as well, usually coming from aircraft.
Roll bars were not there from the start, not even the hoop style. It wasn't until after a few fatal accidents that NASCAR required them, IIRC, for 1955 (after Lou Figaro's fatal accident in October of 1954). Cages were unheard of until into the 60's.
While not heavily covering the rules and technology, Greg Fielden's "40 Years of Stock Car Racing" does touch on these and several other items in that area. I'll dig that out and get his exact passage on the roll bars.
One of the very first deviations from "stock" came as a result of safety issues. Something like three of the first four fatalities involved Hudson Hornets breaking axles or losing wheels. These would in turn become trapped in the fender well on the Hornet, usually resulting in a series of nasty flips. For this reason, NASCAR allowed the Hornets to use stronger suspension parts from another manufacturer and to remove the fender well. With so much of racing on some very rough dirt tracks, I would imagine it wasn't too long before all makes were allowed "stronger" (i.e. truck) parts.
Not to take this into another direction, since it's not NASCAR - or their top division, but short track Stock Cars varied (and still vary) wildly even from track to track. I will always remember when I was 6 or 7 years old and walking toward the ticket booth at Orange Show Speedway in San Bernardino, California. The family had to step aside to let a car pass. In line at the ticket booth, I watched as the driver got out of the car, took a screwdriver and took out the headlights, wrapped them in a cloth and put them onto the back seat of the car, wrapped a chain around the door post, put on a helmet and then drove through the pit gate - license plates and all! This was 1965, and this was one of the top drivers there...yes, they were very stock.
The local track near San Diego (Cajon Speedway) had fiberglass bodies and tube frame chassis in the late 60's. Hollow frame rails allowed for weight to be added where wanted. Yet the local association did not require either firesuits or fuel cells (and only one of the two then) until 1977

Jim Thurman
#5
Posted 25 January 2004 - 01:19
I just happened to have the 1950 rules sheet on my desk when I saw this! There were roll "hoops" from the word go, but not a requirement for them in the begining. Generally the 1953 rules are about the same as the 1950 set of rules. But, "Roll-over bars inside the car are optional but recommended." And, "Roll-over bars are compulsory in hard top model with no center door supports to roof." Also, doors must now be bolted shut. Wheel and tire as for the make and model being raced, with "no special racing tires allowed." Also, the use of approved quick-released safety belts and the wear of an approved safety helmet compulsory.
#6
Posted 25 January 2004 - 02:42
In 1972 I was in a mod/saloon race at Kyalami, and following Chappie Wicks in a highly modified Lotus Cortina. As I entered Sunset I spotted a yellow flag being waved at the top of the bank - an unusual place for a flag marshall at that bend - sufficiently so that I slowed rather more than I normally would have.
Sunset was always a blind bend until you were 2/3rds of the way around it, and as I drove around the last third I saw Chappie's car. He'd well and truly stuffed it tail-first into the bank on the inside of Sunset, and was in the process of an inelegant but high-speed egress. I braked even harder, and Chappie hared across the front of my car for the (comparative) safety of the edge of the track ... dressed in a T-shirt, wholly inelegant shorts, and a pair of flip-flop sandals.
Not the picture of sartorial safety.

#7
Posted 25 January 2004 - 03:13
Originally posted by Don Capps
Jim,
I just happened to have the 1950 rules sheet on my desk when I saw this! There were roll "hoops" from the word go, but not a requirement for them in the begining. Generally the 1953 rules are about the same as the 1950 set of rules. But, "Roll-over bars inside the car are optional but recommended." And, "Roll-over bars are compulsory in hard top model with no center door supports to roof." Also, doors must now be bolted shut. Wheel and tire as for the make and model being raced, with "no special racing tires allowed." Also, the use of approved quick-released safety belts and the wear of an approved safety helmet compulsory.
I should have clarified that myself. I'm sure they were recommended but not required, and apparently (and sadly) some definitely chose not to (descriptions of roofs being "pancaked"). I don't recall too many early NASCAR photos where one can see anything resembling even a hoop in the cars and from the looks of some of the photos, some of the photogs practically had their left elbows inside the car

Thanks for posting the 1950 rules. Very interesting reading. I've got a few rules sheets from some short tracks around here myself.
Still, I'll dig out Fielden and see what he has for the various years. He was good about mentioning signifigant rules changes.
One I can add, from Fielden's books, January 1967 at Riverside was the first appearances of window screens on the driver's side. All of the factory Ford teams were using them. As I recall, Fielden gave the name of the Ford engineer credited with coming up with the concept.
Jim Thurman
#8
Posted 25 January 2004 - 12:20
#9
Posted 26 January 2004 - 07:13
What technology?
In NASCAR?

#10
Posted 26 January 2004 - 16:08
Originally posted by Rainer Nyberg
Technology?
What technology?
In NASCAR?
![]()
Be nice, Rainer..... Keep in mind that perhaps it can shown that high levels of technology have not been all that beneficial to the actual racing.
#11
Posted 26 January 2004 - 16:42

Of course there is always some degree of technology involved even in "low-tech" types of racing...
And Jesse James does a great job of showing us all the advanced hillbilly tech in Monster Garage...
And yes, to some degree maybe an ultra high-tech motorsport does not improve racing itself...but it is mouthwatering stuff for us who are tech-nuts as well as racing fans...

#12
Posted 26 January 2004 - 17:12
Originally posted by Don Capps
Seatbelts were an early requirement as well, usually coming from aircraft.
Just curious, when were they first made manditory? Wonder about Indycars too.
#13
Posted 26 January 2004 - 19:46
Originally posted by ehagar
Just curious, when were they first made manditory? Wonder about Indycars too.
In NASCAR, either 1951 or 1952 and USAC in 1957 -- at least for safety harness and roll bars, the safety belt being mandated much earlier although I will have to nose thru my stuff for that info.
Keep in mind that NASCAR has ALWAYS looked at teams and drivers as "independent contractors" and only made items mandatory when "recommendations" either didn't work or it would allow NASCAR to duck any liability issues.
Keep in mind that NASCAR looks at life through the lens of a promoter and you will have a better understanding of why things often go the way they do.
#14
Posted 26 January 2004 - 23:25

The real evolution/innovation of stock cars seemed to lose out to templates and cookie-cutter cars .
My question relating to this article,
TSN story is what Formula 1 technology is being adapted to NASCAR that these owners are so worried about.
#15
Posted 27 January 2004 - 08:28
Just curious, when were they first made manditory? Wonder about Indycars too.
As I know after Ted Horns' death in 1948 his friend and rival Rex Mays had an idea about seatbelts. Next year Mays himself was thrown from the car and another car hit him. After that I think the officials realised that without seatbelts this wouldn't happen.
Also I know a story about Graham Hill in USGP'69. He spun out of track, stepped out of car to push it back on the track, forgot to fasten the seatbelts and then made a mistake again wich costed him serious injuries.
#16
Posted 27 January 2004 - 11:35
It¡Çs easy to mock NASCAR for the lack of technology, but I¡Çm surprised to learn that safety items seem to have been on the agenda almost from the beginning. Roll-cages were only made mandatory by the CSI/FIA/FISA in 1971! Considering the fiery 1960¡Çs, I would guess safety fuel cells were adopted pretty quickly as well.
Another question regarding the roll cages is, when did somebody got the bright idea of using the cage, not only for protection but to actually build a stiffer car?. Those acid-dipped shells from the 1960¡Çs are my candidate, but only a guess.
Jesper O. Hansen
#17
Posted 13 April 2004 - 13:40
Originally posted by Jesper O. Hansen
Another question regarding the roll cages is, when did somebody got the bright idea of using the cage, not only for protection but to actually build a stiffer car?. Those acid-dipped shells from the 1960¡Çs are my candidate, but only a guess.
I have found some info saying that NASCAR started to regulate the roll cage design during the early 1970's thanks to this address: http://www.wwnboa.org/hartman.htm#73
Not very specific, but with a lot of generel tendensies over time, so quite usefull nevertheless.
Jesper
#18
Posted 13 April 2004 - 16:18