Monteman1971 Posted July 3, 2009 Share Posted July 3, 2009 I know we've covered this a bit before but I'm looking for a more definitive answer if possible. At the track my car twisted quite a bit....lifting the left front tire just off the ground. My thought is that if I put an air bag in the right rear, this would eliminate some of that energy being wasted on twisting the car and therefore launching the car faster. Your thoughts? Quote Link to comment Share on other sites More sharing options...
502ci Posted July 3, 2009 Share Posted July 3, 2009 Without a doubt an air bag in the right rear with about 15 lbs. (give or take adjusting for your car) will help with traction. I used to run two in my camro, I would air down the left one all the way and air up the right one to 15 lbs...not only did it help with traction but removed some wheel hop I had. My Dad runs just the right one and it has helped his car. You can't beat the benefit of the bag for the price. I don't remember but what was your 60 ft. time? Bill Quote Link to comment Share on other sites More sharing options...
Monteman1971 Posted July 3, 2009 Author Share Posted July 3, 2009 1.71 60 foot. I didn't have any traction problems but I figure the twisting action could be put to better use. Quote Link to comment Share on other sites More sharing options...
dbreese Posted July 3, 2009 Share Posted July 3, 2009 Hey Steve, I use airbags on my rear setup. At the track I run 17 psi on the passenger side and 0 on the drivers. I still get some twist but with my QA-1's (single adjustables )6 clicks from full soft and UMI relocation brackets and edel adj uppers it seems to help. I don't make near the power you make If you click on the photobucket link where my car is leaving you can see the left front hiked up. You might consider an anti-roll setup from BMR. That is a a very slick setup and does away with the A-body twist. David Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted July 3, 2009 Share Posted July 3, 2009 I don't know guys, unless you'e runnin' for something other than fun the cool factor of the left lift launch (try and say that 10 times real fast) is pretty awesome. You guys run to friggin' fast....stop it....just stop it now...... Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted July 3, 2009 Share Posted July 3, 2009 for photo opps, leave the bag out for better launches, bag it Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted July 3, 2009 Share Posted July 3, 2009 for photo opps, leave the bag out for better launches, bag it there you go, I knew Sam would have the answer..... Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted July 3, 2009 Share Posted July 3, 2009 if you can get some really good pictures of a front tire hanging in the air, always good for bragging to your buddies, and being able to prove it Quote Link to comment Share on other sites More sharing options...
502ci Posted July 3, 2009 Share Posted July 3, 2009 For a really good left front tire off the ground just remove the front swaybar (that is if you are running one)... Although take caution when doing this as your car will act totally different when launching. Steve, I bet you could sneek into the 11's without the bar. Bill Quote Link to comment Share on other sites More sharing options...
72MC Posted July 3, 2009 Share Posted July 3, 2009 For no body twist... go this route. Sway bar set up hooks up to body versus lower control arms. This is the set up dbreese mentioned. So far this is awesome. Of course this is JMO. - Dave Quote Link to comment Share on other sites More sharing options...
Cali Z28 Posted July 3, 2009 Share Posted July 3, 2009 Steve's point is this (we were debating about it yesterday). If he can eliminate the torque pull and have the car come up straight that would that improve his ET. My arguement is that the rear suspension is doing its job if the car leaves straight, doesnt spin the tires and there is no wheel hop. Now all these factors happened at the track. No spin, 1.71 60ft and the car went straight. I added the fact that I have a race rear suspension set up in my car (racing split monos, adjustable shocks and Cal Tracs) solid motor mounts but my front suspension is all stock except for no sway bar. My car has torque pull as well. Every racer I've spoken to said in order for the car to come up equal on both sides the front suspension would have to be set up as well (trick springs and 90/10's) but with a 1.39 60ft I find that unecessary for the 2 times I race a year. My point is there is minimal to be gained if any by eliminating the torque pull. Steve is citing the physics involved which is a little scarey LOL. Any thoughts or am I off base? Quote Link to comment Share on other sites More sharing options...
Monteman1971 Posted July 3, 2009 Author Share Posted July 3, 2009 All I want to know is will I have a better ET with the bag in the right rear......lol.... Has anyone done this...tried it with and without the bag? Quote Link to comment Share on other sites More sharing options...
dbreese Posted July 3, 2009 Share Posted July 3, 2009 Steve's point is this (we were debating about it yesterday). If he can eliminate the torque pull and have the car come up straight that would that improve his ET. My arguement is that the rear suspension is doing its job if the car leaves straight, doesnt spin the tires and there is no wheel hop. Now all these factors happened at the track. No spin, 1.71 60ft and the car went straight. I added the fact that I have a race rear suspension set up in my car (racing split monos, adjustable shocks and Cal Tracs) solid motor mounts but my front suspension is all stock except for no sway bar. My car has torque pull as well. Every racer I've spoken to said in order for the car to come up equal on both sides the front suspension would have to be set up as well (trick springs and 90/10's) but with a 1.39 60ft I find that unecessary for the 2 times I race a year. My point is there is minimal to be gained if any by eliminating the torque pull. Steve is citing the physics involved which is a little scarey LOL. Any thoughts or am I off base? Scott brought up some very good points and he seems to have his suspension setup optimized for his combo(1.39 60' is proof of that). The thing is there are so many variables, springs, shocks, traction, weight distribution, HP/torque, suspension geometry, instant center, converter flash etc. For the causual racer I wouldn't get real rapped up with all this but if ya start bracket racing where you need consistence then these are thing you need to consider. Steve, your car is making some really good power and I'm willing to bet that there is more in the 60'. 1.71 is an awesome short time. I'm thinking with the torque your making you would benefit from a bag in the right rear spring to add some preload and keep the right tire planted and not pulling up into the wheel well when you launch. You may want to experiment removing the front swaybar (quick and easy) and with a prepped track and good air you WILL be in the 11's. Like others have said I don't think it will solve the twist but hey the left wheel launch is soooooo cool! Sorry for the ramble hope this helps. David Quote Link to comment Share on other sites More sharing options...
Heckeng Posted July 3, 2009 Share Posted July 3, 2009 I am no suspension expert. . . . but I did stay in a Holiday Inn Express last night! Kidding aside, I agree with the bag theory. I also think that it would help distribute the force from the wheels to the ground more evenly. Bear with me as I explain my thoughts, I know some of you are already shaking your heads. Let's start with the law of physics---For every action, there is an equal and opposite reaction. When you hit the gas, that force goes all the way to the rear end and is transmitted to it through the driveshaft as a rotational force. In addition to the pinion trying to turn the ring gear to move the car forward, if there is any resistance from the ring gear (like when you hook up) it will also twist on the rear end and this is why the rear end squats on one side. This is where most racers start to think backwards. The Rear end doesn't squat on the right rear because of the engine pulling on the frame, but it really all of the force from the engine acting on the rear suspension. The driveshaft trying to twist the rear end in the counter clockwise direction when looking at the car from the rear actually causes the whole rear end to twist under the car. The right rear rotates up towards the body, and the left rear twists down towards the ground. As the right rear is forced up off of the ground, the whole car basically "falls" back down to the ground and tries to keep the wheel on the ground just due to gravity and from some weight transfer off of the line. This is all energy from the engine that is being wasted in compressing springs and bushings in the suspension. By adding a bag in the right rear, you can counteract the driveshaft rotational force and get it back into moving the car forward. Also, if the rear end twists a lot, you will get noticably more traction on one wheel than the other. Since the right rear is trying to be lifted off the ground by the driveshaft, it has less traction. If you run slicks at the track with a suspension that twists a lot, your left (drivers side) slick will wear quite a bit faster than the right one. I have personally seen this. I have a set of slicks in my garage that I can show you that had that problem unfortunately. Worse than the slick issue, is that more force/traction on one axle can lead to a premature failure of that axle. Just how much time I think you could save? I have no idea but I do think there is SOME there. I would recommend using the bag more for safety and for keeping as much twist out of the frame as possible just because that can't be good for our old cars! Thoughts? Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted July 3, 2009 Share Posted July 3, 2009 I am no suspension expert. . . . but I did stay in a Holiday Inn Express last night! Kidding aside, I agree with the bag theory. I also think that it would help distribute the force from the wheels to the ground more evenly. Bear with me as I explain my thoughts, I know some of you are already shaking your heads. Let's start with the law of physics---For every action, there is an equal and opposite reaction. When you hit the gas, that force goes all the way to the rear end and is transmitted to it through the driveshaft as a rotational force. In addition to the pinion trying to turn the ring gear to move the car forward, if there is any resistance from the ring gear (like when you hook up) it will also twist on the rear end and this is why the rear end squats on one side. This is where most racers start to think backwards. The Rear end doesn't squat on the right rear because of the engine pulling on the frame, but it really all of the force from the engine acting on the rear suspension. The driveshaft trying to twist the rear end in the counter clockwise direction when looking at the car from the rear actually causes the whole rear end to twist under the car. The right rear rotates up towards the body, and the left rear twists down towards the ground. As the right rear is forced up off of the ground, the whole car basically "falls" back down to the ground and tries to keep the wheel on the ground just due to gravity and from some weight transfer off of the line. This is all energy from the engine that is being wasted in compressing springs and bushings in the suspension. By adding a bag in the right rear, you can counteract the driveshaft rotational force and get it back into moving the car forward. Also, if the rear end twists a lot, you will get noticably more traction on one wheel than the other. Since the right rear is trying to be lifted off the ground by the driveshaft, it has less traction. If you run slicks at the track with a suspension that twists a lot, your left (drivers side) slick will wear quite a bit faster than the right one. I have personally seen this. I have a set of slicks in my garage that I can show you that had that problem unfortunately. Worse than the slick issue, is that more force/traction on one axle can lead to a premature failure of that axle. Just how much time I think you could save? I have no idea but I do think there is SOME there. I would recommend using the bag more for safety and for keeping as much twist out of the frame as possible just because that can't be good for our old cars! Thoughts? I don't know Scott, I think I need to take a class first or something... I hope ours runs well enough to get into this problem!!! Quote Link to comment Share on other sites More sharing options...
502ci Posted July 3, 2009 Share Posted July 3, 2009 Scott, excellent explanation...I'm not good with words and have tried to explain that same thing to people and sometimes I get the response that they don't believe me...they insist the right rear tire is getting more traction because they can see all the cars weight being applied to it...so I start over and try and explain it again... I have seen first hand with my monte before I screwed my slicks to my rims how the left rear was slipping on the rim (getting more traction) way more than the right rear. Steve even though you don't have traction issues you are mentioning the body twist and the bag will help stop that and like Scott mentioned no more wasted energy/hp twisting the frame and suspension...resulting in what would have to a faster ET. Bill Quote Link to comment Share on other sites More sharing options...
Monteman1971 Posted July 3, 2009 Author Share Posted July 3, 2009 Thanks guys....I'm going to order a pair of air bags today....for the money...it's worth it. The only bad thing is most of them come in that red color.....lol. I found a set made by Firestone in blue..... Quote Link to comment Share on other sites More sharing options...
Dans '70 Z20 Posted July 4, 2009 Share Posted July 4, 2009 Guess your leaning towards DRAG @ SuperChevy after making this purchase. Dan Quote Link to comment Share on other sites More sharing options...
Heckeng Posted July 4, 2009 Share Posted July 4, 2009 Scott, excellent explanation...I'm not good with words and have tried to explain that same thing to people and sometimes I get the response that they don't believe me...they insist the right rear tire is getting more traction because they can see all the cars weight being applied to it...so I start over and try and explain it again... I have seen first hand with my monte before I screwed my slicks to my rims how the left rear was slipping on the rim (getting more traction) way more than the right rear. Steve even though you don't have traction issues you are mentioning the body twist and the bag will help stop that and like Scott mentioned no more wasted energy/hp twisting the frame and suspension...resulting in what would have to a faster ET. Bill Thanks for backing me up Bill! I too have tried to explain this to others and they don't believe me. It's hard to get them to understand if their minds are already made! Steve, it would be very interesting to see if with only the air bag change you got a timeslip improvement. Hopefully you can get a day with similar track conditions to test the bags out! Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted July 4, 2009 Share Posted July 4, 2009 Originally Posted By: 502ci Scott, excellent explanation...I'm not good with words and have tried to explain that same thing to people and sometimes I get the response that they don't believe me...they insist the right rear tire is getting more traction because they can see all the cars weight being applied to it...so I start over and try and explain it again... I have seen first hand with my monte before I screwed my slicks to my rims how the left rear was slipping on the rim (getting more traction) way more than the right rear. Steve even though you don't have traction issues you are mentioning the body twist and the bag will help stop that and like Scott mentioned no more wasted energy/hp twisting the frame and suspension...resulting in what would have to a faster ET. Bill Thanks for backing me up Bill! I too have tried to explain this to others and they don't believe me. It's hard to get them to understand if their minds are already made! Steve, it would be very interesting to see if with only the air bag change you got a timeslip improvement. Hopefully you can get a day with similar track conditions to test the bags out! wouldn't it be cool if them bags got Steve into the 11's !!! would probably start another group purchase....great job Scott and Bill, I think I finally understand now.... Quote Link to comment Share on other sites More sharing options...
Heckeng Posted July 4, 2009 Share Posted July 4, 2009 That or we fooled you this time! Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted July 4, 2009 Share Posted July 4, 2009 That or we fooled you this time! you kidder....no it was great, it's just at the beginning anything written that long scares me...like picking up the instructions to the DVD player.... ....now you have to esplain to me how to use them... Quote Link to comment Share on other sites More sharing options...
Cali Z28 Posted July 4, 2009 Share Posted July 4, 2009 Hey Scott, I've agreed with you the whole time and the logic and physics make sense...but if the car is not spinning and leaving straight the gains I believe would be very small. We are racing in July in PA, the elevation will be probably smiliar the temp will be way different. We shall see. Quote Link to comment Share on other sites More sharing options...
Heckeng Posted July 4, 2009 Share Posted July 4, 2009 I agree with you too Scott, I think we are on the same page. I would imagine that the improvement would be small, but I still recommend the bags for keeping the frame from cracking from twisting, and the axle/tire issues. Even if he is hooking up, there is still energy wasted in binding up the suspension and twisting the frame. It is easiest to pick up time off the line too, so if when he hits the gas, the car goes forward instead of squatting and twisting, maybe we will be surprised? Hopefully we are wrong and he picks up a tenth or two but I doubt that will happen. I don't really feel like I can argue a whole lot with a guy who already runs 10's when I can only do 12's! Obviously you are doing something right! Quote Link to comment Share on other sites More sharing options...
Cali Z28 Posted July 5, 2009 Share Posted July 5, 2009 Lol....I think it's more like a discussion and looking forward to see if he picks up any ET Quote Link to comment Share on other sites More sharing options...
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