Forum: HoseHeads Sprint Car General Forum (go)
Moderators: dirtonly  /  dmantx  /  hosehead

Click here, for link to Hot Rod article.

For ~$900 MSD offers a user programmable ignition box with individual cylinder timing and slew control.

Seems like it puts $4,500 Davis Technologies systems to shame?

 
 
 
They don't even know how to spell sprint car 
much less chromoly...http://www.ycmco.com

its about time cheating becomes affordable...now get rid of the 410CUI rule and make horsepower affordable with less rebuilds per year.

Lincoln 1845 ft/.35 mile T1=118MPH 
Eldora 2287 ft/.43mile T3=135MPH
Port 2716 ft/.51 mile T3=TBD
Grove 2792 ft/.53 mile T3=135MPH
Selinsgrove 2847 ft/.54 mile T1=136MPH
"I didn't move to PA from El Paso in search of better 
weather." Van May

Which then begs the question... "Why do 360 engines last twice as long?"

Unhooking the cars is the key. Then it won't matter what size engine you run.

 
 
 
They don't even know how to spell sprint car 
much less chromoly...http://www.ycmco.com

Maybe some of the sanctioning bodies should make MSD systems illegal. If they want to play both sides of the rules.

Tell me how much money you got and I'll tell you how 
fast you can go!

Wouldn't having that 500 c.i. truck motor put you at a weight disadvantage that you couldn't overcome with horsepower? Wouldn't your motor builder also try to build the motor with about a 17:1 compression ratio, giving it a short life-span as well?

maybe now some of the lesser funded teams will be able to compete with what the high dollar teams have had for some time. lets face it, TC is out there and being used where ever it can be of benefit. the ones with the most funds have been able to afford the best money can buy. if the woo or any other descently funded organizations wanted to police it, it could. there are machines that can test ignition boxes. if they tested teams boxes, and sealed them upon approval, they could controll things better as there is no real reason for the user to open an msd box unless they are wanting to connect the battery for the TC. the units come from the factory rivited together, yet you see units with the rivits replaced by bolts all the time. i have heard that the TC can be hidden in any component of the ignition system including the tach, but still you need a battery to power the TC as far as i know. then you have the wireless systems with a transmitter that can be put in a drivers pocket and the system can be controlled with it. but the transmitter just keeps you from having to physically plug anything into the ignition box where the TC device is commonly reputed to be placed. you still need to connect a battery inside the box as far as i know. that gets me back to organizations needing to maybe at least think about sealing boxes and policing it. that is if they are serious about trying to keep TC out of their racing. i do not really know wtf should be done to tell you the truth. i can think of ways to beat most of the ways i could think of to police the deal. that is short of everyone presenting their boxes for inspection at each race and having them sealed right there upon passing.

i suppose that the msd box being described in this thread could be outlawed by oranizations, but without strict policing it would not matter as some would figure out how to slip it by.

I would love to see the hammer come down on the "cheaters". All other sports have busted balls over steroids which make athletes stronger and faster, but you can put a fat guy in a race car and steroids under the hood. Find a way to make sprint car racing "more affordable" otherwise its going to be Kasey Kahne racing VS. Tony Stewart racing and the King will probably be driving for one of them! When these guys swap 3 motors and get a provisional to get into the show its ridiculous!

The Moe and Larry Traveling Road Show (formerly WoO) can't test lest they be tasked with the unpleasantness of enforcement and accountability.

Their fuel testing is a joke; Traction Control technology is light years ahead of their detection methodology...and what about the teams "soaking" those right rears???

Davis Technologies still has the best unit available, and their units do not require an external sensor. They control wheel spin at the crankshaft through the distributor signal.

I've got one on my custom Chevy 1500LS (formerly possessed by the devil - Crew Chief 47...it took me six different BCM/PCM combinations but I got rid of the pulse)...and it feeds regularly on anything/everything most American and European hot rods have to offer.

"As long as I can have a fast boat, a margarita 
machine and can light my hair on fire, I'll be just 
fine."

Jason Giambi

MSD's slew control works the same way as Davis Technologies... at a fraction of the cost, along with also having the capability of being able to alter individual cylinder timing curves using a laptop.

As MSD puts it, the Slew Rate Rev Limiter built into its new PN 7531 Programmable Digital-7 ignition controls traction without being "traction control." In addition to being strictly prohibited by many sanctioning organizations, traction control also implies the use of real-time inputs from a wheel or driveshaft to detect a loss of traction with the road surface, while the Programmable Digital-7 Plus simply measures the rate of the engine's rotational acceleration and applies a rev limiter as needed to keep that rate of rpm gain within preprogrammed limits.

For years, traction-limited racers have used timing controllers to control the amount of power applied to the rear tires to prevent them from spinning, such as when launching a high-horsepower drag car on smaller-than-ideal tires. By retarding timing to reduce engine output at launch, and then using a timer to adjust when the retard deactivates, racers can control the amount of power their chassis and tires can handle much more consistently than by "peddling" the car with seat-of-the-pants throttle application. For example, a drag radial racer with a 1,000hp big-block might pull out 10 or 15 degrees of ignition timing for the first 0.5 second of a run, effectively launching with 600 or 700 hp, before bringing in the engine's full output later in the run as the car is moving and less likely to break traction. Nitrous can also be progressively controlled to prevent it from coming on too soon or too hard. The result of that control is maximum speed and consistency.

MSD's new Slew Control takes the concept a step further by actually controlling the engine's rate of acceleration with a rev limiter to prevent the engine from revving any faster than its available traction can support. The result, when properly set up, is the elimination of unwanted wheelspin at any stage of a dragstrip pass, without the need for any external inputs that would constitute an illegal traction control system. The key here is that you must have it properly programmed. If the Slew Rate is set too low, the engine will be on the limiter too much and slow the car down; if it's set high, you could still go into wheelspin. This makes the Slew Control feature a powerful tool, but one that still requires a knowledgeable tuner to produce a winning result.

According to MSD, the concept of the Slew Rate rev limiter was developed for drag boat racing, where the way the boats launch often causes their engine-driven impellers to come out of the water, causing engine revs to skyrocket until the impeller comes back down into the water, bites, and propels the boat forward. With the ignition controlling the engine's rpm at an acceleration rate set by the Slew Rate Rev Limiter, the engine speed won't climb to the maximum rev limit if traction is momentarily lost.

The Slew Rate can be set to allow the engine to accelerate at a rate of anywhere from 100 rpm per second up to 9,900 rpm per second. At a rate of 1,000 rpm per second, for example, it would take the engine 5 seconds to rev to 5,000 rpm no matter how deeply you stepped into the throttle. If a slipping clutch or spinning tires cause the ignition system to sense that the engine is accelerating beyond the rate programmed Slew Rate, the rev limiter slows the engine's acceleration, thereby preventing tire spin. The Slew Rev Limit is tuned by comparing the RPM slope of an optimum baseline acceleration run and matching the computer-controlled acceleration rate of the engine to duplicate it. Under ideal traction conditions, this results in virtually unbeatable pass-to-pass consistency; in less than ideal traction conditions, it allows precision tuning to maximize the traction available without sacrificing that consistency. Too cool.

The technology obviously has applications in high-end drag racing, which MSD recognized by testing prototypes of the new system on several NHRA Pro Stock cars during the last off-season. In NHRA Pro Stock, the name of the game is tuning the multi-disc slider-type clutch that progressively applies power to the rear tires in a fine balancing act to match power to track conditions without tire shake or wheelspin. Slew Control allows a crewchief to set up a different rate for each gear that limits the engine's rate of acceleration if the ignition sees jumps or quick spikes in rpm, indicating that the tires are slipping. Let's say, for example, that a Pro Stock engine accelerates at a rate of about 4,800 rpm per second. With the acceleration rate programmed into the ignition, any wheelspin that caused the engine to accelerate faster than 4,800 rpm per second would tell the Slew Rate Rev Limiter to come on for as long as it takes to bring the engine's acceleration rate back to the preset level. Ideally, the system limits the rate of acceleration just enough to keep the tires biting into the strip, without applying the rev limiter too often. The key is tuning right to the edge of that fine line of traction.

In addition to Slew Control, MSD's Programmable Digital-7 Plus ignition incorporates many other sophisticated timing controls that have become standard in high-end pro-type ignitions, including the PN 7530 Digital-7 it is based on, Individual Cylinder Timing, which allows the spark timing of each cylinder to be tuned to compensate for rich or lean tendencies, and a 20-second data-logging function that records up to 15 separate parameters. Other features include four rpm-activated rev limits that allow separate limits to be set for the burnout, launch, and primary high-rpm limit. MSD added a fourth rev limit that is useful for turbocharged cars that need to spool the turbo prior to doing a burnout or after pre-staging prior to the launch. Additional features include three staged timing retards that can be set based on time or rpm; a start retard for high-compression engines with locked-out timing; and a programmable shift-light controller that can set different rpm shift points for each gear change. In conjunction with an optional manifold absolute pressure (MAP) sensor, the system can even retard timing based on boost pressure from a turbo or blower.

The result of all this high-technology is virtually unlimited control over the functions of an engine, provided you understand what it's doing and how to use it. Just like having power you can't put to the ground, having features you can't use won't make your car any faster. But in the hands of a capable tuner, the Programmable Digital-7 Plus is undoubtedly MSD's best ignition yet.

 
 
 
They don't even know how to spell sprint car 
much less chromoly...http://www.ycmco.com

Faster Pussy Cat the way your post sounds you are making it sound like i sold you a traction control and / or i am possesed by the devil when all i told you to do with your truck was to look at the bcm / pcm and or a ground problem i dont have and have never had to my knowledge a traction control

You guys don't really think people are using traction control do you? I think it's a myth. BTW, don't look at the small photo in the corner!

www.Numbersusa.com  

oh for Christ's sake...

CrewChief47 NEVER sold me any sort of traction control device...and if he is possessed by the devil, that's between him and the devil!

i swapped six different BCM/PCM combos in and out of my truck (formerly possessed by the aforementioned devil) before i cured its ills. what a pain in the a$$.

once again, CrewChief47 NEVER sold me any sort of traction control device; fuel additive; and he has no knowledge of right rear tires soaking in low grade solvents either...

"As long as I can have a fast boat, a margarita 
machine and can light my hair on fire, I'll be just 
fine."

Jason Giambi

Faster i knew what you were saying but you know how some people blow things out of shape and the only reason i even said anything is because i sell alot of parts on ebay and i dont need any problems if you know what i mean and i cannot beleive it took you that many computers before it was right as for the devil some days i could be possessed LOL Ed

are we going to try to pass xylene as a low grade solvent for this discussion or is that a whole new disclaimer topic?

ok, i didn't read the whole thing but it seems to me msd is trying to pass off this box that can controll traction as a non-traction control device by redefining what they consider to be the definition of how traction is controlled. of course drag cars use some sort of traction control. they use a lot of forms of it from controlling clutch engagement to ingition timming to fuel curve settings. still that is all pre-programed to happen at specific times and specific amounts in the run. it is determined by the tuner and not controlled dynamically by a processer. if somthing other than the drivers foot is dynamically controlling wheel speed on a sprinter or just about any other vehicle, i am gonna say i would call it traction control.

ok... coffee just exited my nose at a high rate of speed!

MSD's re-definition of a traction control device brought to mind Wild Willy's juxtaposition on oral sex.

"As long as I can have a fast boat, a margarita 
machine and can light my hair on fire, I'll be just 
fine."

Jason Giambi