Click on the logo below for the most complete Dirt Late Model coverage anywhere

For the Best RV Sales and Service


Rich's Articles & Blogs


« Double File Restarts!!! | Main | The time may have finally come to move Daytona to the end of the NASCAR schedule »

Here’s a way to get rid of restrictor plates and improve competition

By admin | June 29, 2009

By Richard Allen

Cars racing in NASCAR go too fast.

I know it sounds a bit strange to say that race cars are going too fast. But just going fast is not all there is to racing. If that were so, qualifying is all that would ever be needed. Great racing comes from both speed and competition.

So, here’s a question. When sitting in the grandstand of your favorite track, can you tell the difference between a 31 second lap and a 32 second lap?

Without a stopwatch it’s not likely the difference in speed is noticeable. Fast is fast, whether it’s 175mph or 160mph. What is noticeable is the closeness, or lack of closeness, of the competition.

The closest racing on the NASCAR circuit occurs at two tracks, Daytona and Talladega. The reason for this is that the horsepower of the cars is reduced artificially by restrictor plates. These plates, as the name implies, restrict the air and fuel flow into the engine and thus rob the engine of its ability to make power.

Restrictor plates became necessary when in 1987 Bobby Allison’s car very nearly sailed into the grandstand at Talladega. Fearing the consequences of such a thing happening NASCAR began placing the plates on cars for all races at Daytona and Talladega.

Restrictor plates had also been used during the 1970s in the time of an engine downsize effort to encourage teams to use a smaller, unrestricted engine.

This weekend, the NASCAR Sprint Cup Series will make its traditional mid-summer trip to Daytona Beach for the Coke Zero 400. As is always the case when a race is held on one the two high speed tracks, restrictor plates will be thoroughly discussed.

Restrictor plates could be done away with and racing could be improved on all tracks if engine displacements were reduced. And when I say reduced, I mean significantly reduced.

NASCAR had an opportunity to downsize engines when they introduced the Car of Tomorrow in 2007. Perhaps they thought it would be too much to change both the engine and the body at the same time. However, by waiting they have allowed each of the four manufacturers to submit new engine designs which cost millions of dollars in research. Now, the sanctioning body is stuck with an engine that produces far too much horsepower and very little competitive racing.

Restrictor plates in use at every track would reduce horsepower, but that is definitely not the answer. A good example of why not can be seen from an event held on the same track NASCAR just competed on, the New Hampshire Motor Speedway.

After the deaths of Adam Petty and Kenny Irwin, NASCAR feared the cars were carrying too much speed into the turns on that track. So, they mandated the use of plates for one race there in 2000. That race was one of the worst events every sanctioned by NASCAR. With no throttle response, the cars could not get the necessary jump off the turns and thus could not gain the needed momentum to pass. Jeff Burton led every single lap of that race.

With restrictor plates out of the question, the best alternative is to reduce the cubic inch displacement.

I am not a mechanical engineer so I am not going to throw out a number that the cubic inch displacement should be reduced to. However, it is widely speculated that the current 358ci creates approximately 800-850 horsepower. Whatever cubic inch displacement that would bring those numbers down to the 600-650 horsepower range would seem to fit the need.

As was stated before, a fan sitting in the stands cannot see the difference between a car going 175mph or a car going 160mph as they go around by themselves. What the fan can see is that right now the cars are going so fast that drivers are simply doing their best to hang on rather than pass the guy in front of them.

Granted, it would not take long for the teams to have those horsepower numbers back up to old levels even with cubic inch reductions. At which time, other adjustments would have to be made.

The problem with making such a move is that of cost. For NASCAR to mandate a drastic reduction in engine size would cost teams a fortune at a time when they can least afford it.

Such a change would have to be announced at least one year ahead of time, and probably phased in gradually. This should have been done 5-7 years ago, but that is not worth debating now.

To be proactive, NASCAR could designate an engine builder, not already associated with any team, to build so called ‘spec’ or ‘crate’ motors for any team who did not want to take on the task of making the change. Unlike dirt racing, however, teams could be allowed to make their own modifications to these motors upon receipt.

Teams who wanted to build their own engines could go ahead and do so.

Cars in NASCAR are going much too fast and are making far too much horsepower. They are using an engine that was brought in during the 1970s and has had few adaptations made in over thirty years. It is past time for a change, but the problem is the change may not be feasible at this time.

As is so often the case, NASCAR needs a time machine to go back and make corrections that should have already been made.

Richard Allen is a member of the National Motorsports Press Association. His weekly column appears in The Mountain Press every Wednesday.

Topics: Articles |

6 Responses to “Here’s a way to get rid of restrictor plates and improve competition”

  1. Prof pi (Jeff Thompson) Says:
    June 30th, 2009 at 8:43 am

    You’re spot on about the perception of racing: how close is your favorite driver to the car ahead, and are passes for position being made on the track. And, no, without a stop watch the average fan, even a sophisticated one, can’t discern the difference between 185 mph and 145 mph.
    Look at my current blog, I plotted qualifying speeds at Daytona by year, at it is very obvious when engine size limits kicked in.
    First problem is NASCAR Daytona refuses to admit they have a problem with COT; so forget about realistic chances of changing anything.
    There are essentially three ways to restrict speeds and be competitive: (1) completely stock body shapes, no added aero effects; (2) smaller displacement engines; and (3) a team gets 30 gallons of fuel for the weekend: practice, qualify and race, however, unlimited energy from completely renewable sources (solar, wind, biomass, etc.). For the latter one, if a car is safe for the driver and fans then NASCAR would put a number on anything with 4 wheels. It would become the era of a 1000 Smokey Yunick mechanical wizards–in the late ’60’s it was called Can-AM.

  2. Charles Says:
    June 30th, 2009 at 9:58 am

    I agree that the speeds especially on the 1.5 mile tracks has really been escalating!

    I like you think that Nascar should be looking down the road to see this problem! In the 70s remember when they went from 427 cubic inches to 358 cubic inches they phased it in so you could still run the 427 with smaller sleeve, or restistor plate and if a team such as Bud Moore did with the 351 could use a large carburetor! This way the low budget teams could still use up there equipment for a few years!

    Lowing cubic inches, lower octane fuel, these cars in the 70s use to weigh 3,700 lbs, so adding weight to a car would help, I never seen many tires issues in the 70s or eighties with the heavy weights! Go back to the bias ply tire! I think they should get a car from the Darlington Museum, say David Pearson 1971 Mercury, Cale Yarbroughs 1978 Oldsmobile and carry to wind tunnel. and check engines with that spec, and use that as a model!

    Where Nascar over regulates is the car! I dont think they should be ‘checking horsepower”! They should create specs like cubic inches, heads, manifold, etc like they did for 30 years and see if it in spec, they should let the car owners do the protesting!
    Checking each teams horsepower create a ’socialism system” in Nascar and keeping every one equal is one of the reasons they dont pass!The gear rule is another thats needs to be changed! Let the car owner decide!
    Now they carry the engines back to Charlotte and tested behind close doors!

    One day, I think you will see a ‘Scandal” in their testing program in where a car owner with a lot of money could bribe and get information on another teams engine! Checking engines in front of the other competitors is the better way of doing it!

  3. Fred Says:
    June 30th, 2009 at 4:25 pm

    Your idea would make tens of millions of dollars worth of in stock Nascar Cup series engines instantly obsolete.
    Who can pay such a high price?? The Owners? The manufacturers? The sponsors?
    How about sports journalists, now there is a plan!

  4. Tom Says:
    June 30th, 2009 at 6:45 pm

    Uh Guys, If I am not mistaken, the displacement for the cup motors is and has been 350 c.i.d. nascar just allowed them to go up to 8 cubic inches over to keep from fining the teams. trouble is, enging building is such today they can take it right to the edge, not like the old days when things being close was ok. Take away that fudge factor and they have reduced the hp
    Check it out and see if i am correct.

    Fred, nascar would love to add that price to Carl Long’s bill, the poor guy aint never going to be able to pay it off anyway.

  5. Big Alice Says:
    June 30th, 2009 at 10:46 pm

    Won’t work.
    Less cubic inch = less internal mass = more rpm potential.
    Sort of a catch-22.
    back in ‘71 Big Bill thought 120 cubes LESS would really kill the Daytona Charger. Anyone that saw that race will remember the little 305 Mario Rossi had Kieth Black build for it ran quite respectable most of the day compared to the engines vastly larger. Why? Simple…the smaller motor was able to run a LOT higher RPM. Same reason a bike engine can run vastly higher RPM. Granted, they could mandate Trans and Rear gears to limit that problem…but then again, they could do THAT with the current engines.

    They DO need less horsepower, yet there’s no great way to do it.

  6. Charles Says:
    July 1st, 2009 at 9:29 am

    Big Alice

    In 1971 they started made all the 427, 426 cubic inch engines rule small carburetors, and used the sleeve as a resistrictor plate, the 305 that Richard Brooks ran was allowed to run a Winged Dodge Daytona with the larger carburetor! But dont get me wrong he ran well at Daytona with the car! But a unrestricted 427 using the same car would outrun the 305!

    A lot of fans think the first restrictor plate came with Bobby Allisons wreck at Talledaga, but they were using Carburetor Sleeves, Inserts, Plate in the 1970s because of the aero wars with the Dodge Daytona and Ford Talledaga speeds were climbing fast!

    But I liked the idea they had in the 1970s where you could run different spec engines and bodys so the mechanics could be createtive!