REAR AXLE
#11
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Originally Posted by outlaw256
but in reality if you drilled every bolt and axle and anything else you can on a car you aint gonna come up with a pound of metal.
The NASCAR guys spend hundreds of thousands of dollars looking for a quarter of a horsepower. They also spend the same amounts reducing the total weight so that they may (as was said previously) add weight where it will work for them . . A lot of that also goes for the serious drag racers . .
#12
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Not meaning to upset the apple cart here, BUT, almost no 35 spline axles are gun drilled, only 40 spline or bigger. Most axles are 4340 or better 9310 steel. Neither one of these material are harded thru, it's impossibe, so they are ecentually case hardened. So they are gun drilled before heat treating, therefore the case hardening is on the inside and outside of the axle therefore making them stronger. Quicker accerlation comes from a lighter rotating mass which is critical in drag racing. The ProStock guys are running titanium spools also to lighten the rotating mass, just as they are running titanium rods for quicker acceration.
Zip.
Zip.
#13
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Join Date: Nov 2009
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Moser, Strange and Winters all have 35 spline gun drilled readily available. I have them in my floater axle Trac 9 in my dirt modified, as do most dirt late models and modifieds...
Here's just one of many ads on the net for drag axles...
http://centralracingparts.com/index....product_id=311
Here's just one of many ads on the net for drag axles...
http://centralracingparts.com/index....product_id=311
#14
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Location: La.
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Originally Posted by DRTRCR22
Moser, Strange and Winters all have 35 spline gun drilled readily available. I have them in my floater axle Trac 9 in my dirt modified, as do most dirt late models and modifieds...
Here's just one of many ads on the net for drag axles...
http://centralracingparts.com/index....product_id=311
Here's just one of many ads on the net for drag axles...
http://centralracingparts.com/index....product_id=311
higher RPM
Zip.
#15
I had heard a bunch of guys say they would not drill old axles and have also heard it wasn't worth the cost and I would be better to just upgrade to 40 spline axles (40 spline drilled are lighter than 35 non drilled) so I called moser and and asked if they would drill my 5 year old 35's. They said yes and for only $50 per axle. Needless to say they are going to Moser in the next few weeks.
#16
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I agree Zip about the hammer drop at high rpm, however the twisting forces from hard bite around the corner on a heavy tacky dirt track with spool locked axles is pretty fierce too.
In the modified class with spec tires that only have a stagger range of less than 1" out of the mold, we have no real way to offset tire circumference stagger for the corners, so that's where the rear steer via four bar offset comes into play to keep from twisting the axles from different wheel speeds.
On a drag car hopefully both axles are feeling the same rotational twist and the same tire spin if any, where on a dirt car the rear wheels spin loose in a bind alomst all the time. That's also why it is mandatory in dirt mods and late models to run floating axle hubs so if you do twist break one in the corners the hub and wheel stays on the car until you coast to safety. I have seen many dirt street stock cars without floater axles do barrel rolls coming out the coners when a wheel and hub break off... :shock:
In the modified class with spec tires that only have a stagger range of less than 1" out of the mold, we have no real way to offset tire circumference stagger for the corners, so that's where the rear steer via four bar offset comes into play to keep from twisting the axles from different wheel speeds.
On a drag car hopefully both axles are feeling the same rotational twist and the same tire spin if any, where on a dirt car the rear wheels spin loose in a bind alomst all the time. That's also why it is mandatory in dirt mods and late models to run floating axle hubs so if you do twist break one in the corners the hub and wheel stays on the car until you coast to safety. I have seen many dirt street stock cars without floater axles do barrel rolls coming out the coners when a wheel and hub break off... :shock:
#17
I've seen several GM 'c' clip axles break and that loose and really rollin' tire hub and axle stub come blowing into the pits! :shock:
Even saw one guy 'TRY' to stop one with his foot from the FRONT. One broken axle and one broken leg. :roll: :roll: :roll: :roll: He won't be doing THAT ever again.....
Even saw one guy 'TRY' to stop one with his foot from the FRONT. One broken axle and one broken leg. :roll: :roll: :roll: :roll: He won't be doing THAT ever again.....
#18
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Accordingly SOLELY on things I have read on this subject-gun drilling an axle is supposed to allow the entire length of the axle wind/wrap up,absorbing a fair amount of the initial "hit",therefore strengthening the axle. The idea is if it can wrap a little,maybe it wont snap the splined end off. Improved torsional fatigue,I believe is what they call it.
#19
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Actually, from an engineering standpoint, a "Rifle Drilled" or "Gun Drilled" Axle or shaft is stronger than a solid round billet, no matter how the original shape was formed.
A tube distributes shear along the sides of the shape and won't twist as a bar or solid shape of any kind would . . Using a 1" X 1" square bar as an example, but a 36" bar in a vise and twist or bend it. While that may require a cheater on the wrench to twist, it's not that hard . . now try the same thing on a 1" X 1" X 1/8" tube . . If you twist it at all, it took a bunch, and probably a lot longer (and stronger) cheater . . What makes it so tough is the four 1" X 1/8" I beams you have to deform.
With a round tube, the I beams are just smaller and more numerous, literally. Stronger and usually a third to a half the weight . .
But . . they don't "Wrap up" to any degree at all, simply because once they twist, they're gonna fracture oe deform, followed by failure. You can't twist a tube, but you can a bar successfully, many times. A torsion bar is a good example. But you won't find "Torsion Tubes" . .
A tube distributes shear along the sides of the shape and won't twist as a bar or solid shape of any kind would . . Using a 1" X 1" square bar as an example, but a 36" bar in a vise and twist or bend it. While that may require a cheater on the wrench to twist, it's not that hard . . now try the same thing on a 1" X 1" X 1/8" tube . . If you twist it at all, it took a bunch, and probably a lot longer (and stronger) cheater . . What makes it so tough is the four 1" X 1/8" I beams you have to deform.
With a round tube, the I beams are just smaller and more numerous, literally. Stronger and usually a third to a half the weight . .
But . . they don't "Wrap up" to any degree at all, simply because once they twist, they're gonna fracture oe deform, followed by failure. You can't twist a tube, but you can a bar successfully, many times. A torsion bar is a good example. But you won't find "Torsion Tubes" . .