PRO-STOCK burnout question (1 Viewer)

[.]

Do they shift thru the gears or does it stay in 1st or something like that?

BTW, Mike Dunn in P/S was fun to see.

 

[na]

Do they shift thru the gears or does it stay in 1st or something like that?

BTW, Mike Dunn in P/S was fun to see.

I think they do the burnout in 3rd gear. Am I right....if not someone correct me.

 

[Fast Al]

With a 4-spd, you let the clutch out in 3rd gear at about 6000rpm, run it up to about 7500, then pull it into hi gear, release the line lock and drive it out. I assume you do the same with a 5-spd, only starting in 4th.

 

[Bad Rat]

Do they shift thru the gears or does it stay in 1st or something like that?

I start out in 3rd Gear with the Motor at around 4800-5000 RPM, let the clutch out. While bringing the Motor up to betweeen 7400-7800 RPM start pulling the Gears until I am in 5th using "Ankle Management" to keep the Motor in the correct RPM Range. Once in 5th release the Line Lock and head for my Crew Chief's feet with the left Rear Tire. He always seems to get out of the way.

Some people start out in 2nd but I like to get the tire speed up without a whole lot of Motor speed thus saving the Valve Springs for the pass.

 

[Rollout96]

Once in 5th release the Line Lock and head for my Crew Chief's feet with the left Rear Tire. He always seems to get out of the way.

don't you hate those fleet-footed crew chiefs?

 

[Bullet]

I start out in 3rd Gear with the Motor at around 4800-5000 RPM, let the clutch out. While bringing the Motor up to betweeen 7400-7800 RPM start pulling the Gears until I am in 5th using "Ankle Management" to keep the Motor in the correct RPM Range. Once in 5th release the Line Lock and head for my Crew Chief's feet with the left Rear Tire. He always seems to get out of the way.

Some people start out in 2nd but I like to get the tire speed up without a whole lot of Motor speed thus saving the Valve Springs for the pass.

Pat,

Does starting the burnout in 3rd instead of 2nd make a difference to the clutch (ie additional wear), or does the counter weight and base pressure make up for the higher ratio in getting the tires spinning?

You would need a little more RPM at the moment you let the clutch out to get the tires spinning in 3rd than you would in 2nd, wouldn't this be a little harder on the valve springs? Or are you talking about the sharper acceleration of engine RPM in 2nd after the tires are spining resulting in higher RPM for longer?

If it does have an impact on the clutch, what do you do to compensate for it?

Cheers,

Paul

 

[mike]

This thread leads me to a probably naive question that's been bugging me for a long time. I understand the rationale for the burnout, ie. heating the tires and providing tire tracks on the racing surface with additional stickiness for the launch. But you do this at the risk of parts breakage/wear and possible loss of a run (eg. Mike Ashley and Greg Anderson this past weekend). Is it worth the risk? For example, Ron Capps did not appear to suffer any ill effects of his ultra-mini-burnout when running against Force in the first round at Firebird.

What about using heater tape to place the rubber at a precise temperature while in the staging lanes? This would give the crewchief the added flexibility of setting the two tires at different temperatures to deal with possible irregularities in the track.

 

[Bad Rat]

Pat,

Does starting the burnout in 3rd instead of 2nd make a difference to the clutch (ie additional wear), or does the counter weight and base pressure make up for the higher ratio in getting the tires spinning?

You would need a little more RPM at the moment you let the clutch out to get the tires spinning in 3rd than you would in 2nd, wouldn't this be a little harder on the valve springs? Or are you talking about the sharper acceleration of engine RPM in 2nd after the tires are spining resulting in higher RPM for longer?

If it does have an impact on the clutch, what do you do to compensate for it?

Cheers,

Paul

Paul,

We haven't seen any wear differences between my Clutch and Jerry's Clutch. He starts in 2nd and I in 3rd. Since I get the fun job of grinding the disks I haven't noticed any real measurable differences to speak of.

The RPM is really deceiving. You will notice up close to the cars live and in person usually the RPM at the time of dumping the Clutch is only about 4000-5000 RPM but once the Clutch is out the Driver needs to "get up on it" and keep the RPM from dropping below the point where the Counterweights become in-effective and cause the Tires to stick thus a burnt Clutch and if you run it up to high you can spit the Push Rods out or take the Springs out of it.

The first time I ran a 500 inch Motor in my Cavalier in June of '04 Jerry warned me this Motor will out accelerate the 568 and 582 Motors I was use to. He told me not to let it run away. Not knowing what to anticipate it did run away leaving a Push Rod lying in the Valley. I learned real quick how to do a burnout after that. Jerry had the Crew attach the "Leash"...the Burnout Rev Controller. It was set for 7400 RPM and it took a few times to get the hang of it but we got it down. We now set the Controller for 8000 RPM and I stay below that. It is a good safety precaution to save on the Valve Springs especially when you are switching between Motors and the Throttle Linkages are quite different as far as Pedal Pressure and Ratios go.

If you ever get the chance at a PS Test Session go up to the line and watch the Drivers during their burnouts. You will see how they drive into the burnout maintaining an RPM while the tires go from no traction in the water to almost full hook at or just past the starting line (Ankle Management). It is really fun to watch when they have a Mule Motor in the car and they are breaking in Tires (some of us do that back at the shop in the parking lot...(KJ & WJ, Adam does a great job of it and we do it here at times however the neighbors are not happy).

Hope that answered your questions.

Pat

 

[Bullet]

Paul,

We haven't seen any wear differences between my Clutch and Jerry's Clutch. He starts in 2nd and I in 3rd. Since I get the fun job of grinding the disks I haven't noticed any real measurable differences to speak of.

The RPM is really deceiving. You will notice up close to the cars live and in person usually the RPM at the time of dumping the Clutch is only about 4000-5000 RPM but once the Clutch is out the Driver needs to "get up on it" and keep the RPM from dropping below the point where the Counterweights become in-effective and cause the Tires to stick thus a burnt Clutch and if you run it up to high you can spit the Push Rods out or take the Springs out of it.

The first time I ran a 500 inch Motor in my Cavalier in June of '04 Jerry warned me this Motor will out accelerate the 568 and 582 Motors I was use to. He told me not to let it run away. Not knowing what to anticipate it did run away leaving a Push Rod lying in the Valley. I learned real quick how to do a burnout after that. Jerry had the Crew attach the "Leash"...the Burnout Rev Controller. It was set for 7400 RPM and it took a few times to get the hang of it but we got it down. We now set the Controller for 8000 RPM and I stay below that. It is a good safety precaution to save on the Valve Springs especially when you are switching between Motors and the Throttle Linkages are quite different as far as Pedal Pressure and Ratios go.

If you ever get the chance at a PS Test Session go up to the line and watch the Drivers during their burnouts. You will see how they drive into the burnout maintaining an RPM while the tires go from no traction in the water to almost full hook at or just past the starting line (Ankle Management). It is really fun to watch when they have a Mule Motor in the car and they are breaking in Tires (some of us do that back at the shop in the parking lot...(KJ & WJ, Adam does a great job of it and we do it here at times however the neighbors are not happy).

Hope that answered your questions.

Pat

Thanks for the overview Pat.

I drove my Dad's Australian Pro Stock for a few races car back in '95 (equivalent of NHRA C/A at the time). We were running a power-sapping 5-speed Lenco at the time and used to start the burnout with the 3rd gear lever back and pull 5th as the RPM started to climb as the tires began to spin freely, then release line-loc and "ankle-manage" the throttle through to the critical point where the car speed started to catch up to wheel speed and you had to get off it and clutch it so that it wouldn't rattle your teeth out.

We did run a burnout RPM limiter, hovever I did did cop a spray from Dad after one over-zealous burnout that had it on the limiter.

 

[DrRocket]

.........For example, Ron Capps did not appear to suffer any ill effects of his ultra-mini-burnout when running against Force in the first round at Firebird.

What about using heater tape to place the rubber at a precise temperature while in the staging lanes? This would give the crewchief the added flexibility of setting the two tires at different temperatures to deal with possible irregularities in the track.

I know I've written this before, but Jim Head, and I suspect a few other drivers have said before that if NHRA (And the fans.) would let him get away with it, he'd dispense with the burn out all together. That's a fuel car though. Not sure bout pro stockers.

I seem to remember that Formula 1 teams used to use tire heater wraps to bring the tires up to near racing temperatures, but I think they were outlawed.

 

[Bowtie]

This thread leads me to a probably naive question that's been bugging me for a long time. I understand the rationale for the burnout, ie. heating the tires and providing tire tracks on the racing surface with additional stickiness for the launch. But you do this at the risk of parts breakage/wear and possible loss of a run (eg. Mike Ashley and Greg Anderson this past weekend). Is it worth the risk? For example, Ron Capps did not appear to suffer any ill effects of his ultra-mini-burnout when running against Force in the first round at Firebird.

What about using heater tape to place the rubber at a precise temperature while in the staging lanes? This would give the crewchief the added flexibility of setting the two tires at different temperatures to deal with possible irregularities in the track.

Also one other reason for the burnout is to clean any debris/rocks from the tires that may be picked up in route to the starting lines. I can remember years ago before Fireturd paved everything, the back wall looked like it was bullet riddled from the rocks.

 

[vegasnitro]

I seem to remember that Formula 1 teams used to use tire heater wraps to bring the tires up to near racing temperatures, but I think they were outlawed.

F1 teams still use tire warmers, they just are not allowed to have them in the pitlane anymore and the maximum allowed temp is 140 degrees. So the tires sit in the garage all day warmed to a nice toasty 140 degrees and at the last possible second when the car is coming down the pitlane the team zooms out of the garage carrying the tires so they can be mounted during the pitstop without losing much heat/temperature. Back in the day, the tires used to sit in the warmers at whatever temperature the teams wanted in the pitlane and the cars would pull right up to them.

 

[DrRocket]

F1 teams still use tire warmers, they just are not allowed to have them in the pitlane anymore and the maximum allowed temp is 140 degrees. So the tires sit in the garage all day warmed to a nice toasty 140 degrees and at the last possible second when the car is coming down the pitlane the team zooms out of the garage carrying the tires so they can be mounted during the pitstop without losing much heat/temperature. Back in the day, the tires used to sit in the warmers at whatever temperature the teams wanted in the pitlane and the cars would pull right up to them.

Thanks for the info Chris!!