Drag springs + sway bars = weight transfer?

RocketcarX

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How much weight transfer are you giving up when switching to "drag" springs like the BMR or Cobra Jet springs and keeping the front sway bar?
I'm trying to draw some lines with my car as far as what is realistic and is "livable" in my quest to build a street legal drag week style car I can race with my son in the years to come.
When I say "lines" I mean I have no A/C, no radio, or even seat belts in the back seat (my son's car seat doesn't need them to anchor). The car is the full BMR suspension with heim joints out back, the only urethane being the front control arms and motor mounts.
Now for the "compromises". Still has fully functioning air bags, power seats, heat, and power everything. eventually I'll ditch the PS and factory front seats, but you get the idea.
The reason I'm sort of laying this out is to figure out if I should just go right to ditching the front sway bar, or can I just set it on the softest adjustment and put the Race Stars on and go racing? My concern is predictable handing during real world situations, emergency braking, evasive maneuvers, etc. Driving slower through corners doesn't bother me, the older I get the less I am in such a hurry to get where I'm going (this may also be proportionate to the amount of deer I've hit out here).
So if I can ditch it for maximum effect and the car is livable and "safe", I'd just as soon toss to for the sake of weight reduction, however this thing has been a lesson in compromise, so there is that too...I would still keep the rear sway bar of course, it's a basic aftermarket performance replacement, later I'll be going to the BMR adjustable deal.
 

Marble

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It only takes a few minutes to remove the sway bar. So you can try it out. IMO, for what you are trying you do you won't notice much difference driving around unless you are trying to corner carve.

Consider with more weight transfer and more traction, you will eventually see one wheel pull up on launch. You'll end up getting an ARB for the rear.

Your car is set up similar to mine. I enjoy driving it around. Srill has power steering but no AC. No factory seats, has Corbeau seats and a cage.
 

RocketcarX

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It only takes a few minutes to remove the sway bar. So you can try it out. IMO, for what you are trying you do you won't notice much difference driving around unless you are trying to corner carve.

Consider with more weight transfer and more traction, you will eventually see one wheel pull up on launch. You'll end up getting an ARB for the rear.

Your car is set up similar to mine. I enjoy driving it around. Srill has power steering but no AC. No factory seats, has Corbeau seats and a cage.

I'll go with a cage at some point too. I have the strange adjustable struts, so I was thinking they might sort of compensate on some level for the lack of a front sway bar by adjusting them a little stiffer for daily driving.
I had both sway bars out when I first got my Race Stars and wanted to try them out and the car did this weird rotating thing while it felt like the entire car lifted up on launch, I didn't like it but honestly attributed to the lack of any rear sway bar. I have the relocation kit for the rear bar now, so it can stay in the car when I'm in drag mode.
 

Marble

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You should never remove that rear sway bar. It helps you at the track.

I control my front end by tightening shocks also. I loosen them up while at the track.

My cage has removable door bars that swing out. Doesn't effect my daily driving but my kids can't get in the back seat anymore.
 

RocketcarX

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You should never remove that rear sway bar. It helps you at the track.

I control my front end by tightening shocks also. I loosen them up while at the track.

My cage has removable door bars that swing out. Doesn't effect my daily driving but my kids can't get in the back seat anymore.

Yeah, I knew it wasn't going to be great without it, it's back in with a relocation kit now so it will clear the 15x10 Race Stars.

One day I'll go with the adjustable BMR deal or their anti-roll set up, lots of other things I need before a $600 roll bar though, more power being one of them.

Once it's safe for my son to ride in the front, I'll delete the rear seat altogether.
 
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JUSTA3V

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I'm running BMR drags springs with my front sway bar at the track. It transfers just fine. I'm cutting 1.5 60 foots. Well I was back when my slicks were in good shape.

I have also ran the cj springs as well with the same results.

The rest of my suspension is strange adj strut set full loose and qa1 doubles in the back set many times at different settings depending on track conditions.
 

Marble

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Yeah, I knew it wasn't going to be great without it, it's back in with a relocation kit now so it will clear the 15x10 Race Stars.

One day I'll go with the adjustable BMR deal or their anti-roll set up, lots of other things I need before a $600 roll bar though, more power being one of them.

Once it's safe for my son to ride in the front, I'll delete the rear seat altogether.

If you wait for one of their discount periods you can get it for a little less than $400. I just bought one and it's sitting in the office waiting for me.

My 60' at its best has been 1.47. I think I have enough power ~600rwhp through a 4r70w to get it closer to 1.40. I plan on scaling my car this winter, finding the instant center for the car and adjusting my control arms so they are at the correct geometry.

The thing is my car is heavy. I would guess 3750 with me in it. Probably more.
 

redfirepearlgt

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I'm running BMR drags springs with my front sway bar at the track. It transfers just fine. I'm cutting 1.5 60 foots. Well I was back when my slicks were in good shape.

I have also ran the cj springs as well with the same results.

The rest of my suspension is strange adj strut set full loose and qa1 doubles in the back set many times at different settings depending on track conditions.

I'm hoping to find solid 1.5's this season with the Strange front adjustable struts and BMR GT 500 front drags I just purchased. I've made a best of 1.62 60ft on R series 17" 305/45/17 MT DR's (radial) with the front end fully stock, and Lakewood 50/50's with BMR rear Drags and all BMR rear suspension with the stock rear sway bar. This is encouraging. THanks for sharing.
 

RocketcarX

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Has anyone done a comparison at so see how the car performed with drag springs with and without the front sway bar?
Those are some quick 60' times for sure!
 

bunits19714

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you have no ac in texas, but you are worried about removing your front sway bar? upgrade the rear to the bmr or a whitline and loose the front sway bar and never look back. the whitline is a lil less expensive and I have gone 1.38's at a 3750 race weight with it- rear sway bar relo brackets are not the strongest mounts and the factory rear sway bar isn't that stiff- I ran a 10ply MT skinnnie and the car handled like is was on factory p zero's- they are heavier than your normal 26" flat bottom skinnie but have absolutely no roll to them and wear really well on the street. And with a wide tire on the front the car is super stable with the super stiff rear sway bar- my 14' has no body roll what so ever because the rear is so stiff. 170mph on MI e-way and smooth as glass- still factory shocks and struts. rest of the rear is all bmr. ** bmr #12 rear springs only
 
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skaarlaj

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No doubt, removing the front sway bar is not a big deal at all. I say take it off, and see for yourself on a test drive. I'm betting alot of people wouldn't realize it was missing. I ran a gen 2 Lightning without one for years, along with a fox body, and 04 Cobra.
 

RocketcarX

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I am going to pull it out and do some back to back testing, I just wanted some input from others that might have already messed around with the difference. I'm waiting on new drag radials to come in first so I figured I could do a little research in the mean time, the search function didn't reveal much, so I decided to ask.
I know it's not a big deal to remove, even with the added BMR brace up front, just curious about other's experiences with this.
 

BMR Tech 2

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I don't really like removing sway bars on street cars, but people do it all the time. I especially don't like removing front sway bars when people are using an anti-roll bar, but people do that all the time too lol. If you'd like to keep the front sway bar, just disconnect a link when you go to the track. It's very easy to do and you should be able to get it done in a couple minutes without lifting the car.

That being said, as long as you're cautious and take the time to learn the car again after removing the front bar, I don't think you'll have any problems.
 

Marble

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I don't really like removing sway bars on street cars, but people do it all the time. I especially don't like removing front sway bars when people are using an anti-roll bar, but people do that all the time too lol. If you'd like to keep the front sway bar, just disconnect a link when you go to the track. It's very easy to do and you should be able to get it done in a couple minutes without lifting the car.

That being said, as long as you're cautious and take the time to learn the car again after removing the front bar, I don't think you'll have any problems.

Is this because it puts a lot of stress on the ARB?
 

RocketcarX

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I don't really like removing sway bars on street cars, but people do it all the time. I especially don't like removing front sway bars when people are using an anti-roll bar, but people do that all the time too lol. If you'd like to keep the front sway bar, just disconnect a link when you go to the track. It's very easy to do and you should be able to get it done in a couple minutes without lifting the car.

That being said, as long as you're cautious and take the time to learn the car again after removing the front bar, I don't think you'll have any problems.

Could you elaborate, plz sir
 

BMR Tech 2

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Is this because it puts a lot of stress on the ARB?

No.

Could you elaborate, plz sir

Stock rear sway bars range from 100 in/lbs to 275 in/lbs. The BMR ARBs range from ~2000% to ~4000% stiffer than stock bars. When you increase rear bar rate (or decrease front bar rate) then you increase the cars propensity to oversteer. When you make an emergency maneuver to avoid a deer, road debris, etc... you can cause the car to snap oversteer due to the insane rear bar rate and relatively low or non existent front bar rate. While an ARB helps a car maintain traction in a straight line by keeping both rear tires loaded, it will prevent the rear from gripping during a turn. This problem can be made even worse when you run pizza cutter tires up front.

As long as you take the time to learn the car, figure out how it reacts when you do certain things, and understand that the car may get away from you during an emergency maneuver, you'll probably be fine. Tons and tons of my customers run no FSB with a rear ARB on daily driven cars, I just like people to understand what they're getting themselves into. Be smart, don't drive like a jackass, maintain safe distance, and keep your eyes peeled. You'll be fine.
 

RocketcarX

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No.



Stock rear sway bars range from 100 in/lbs to 275 in/lbs. The BMR ARBs range from ~2000% to ~4000% stiffer than stock bars. When you increase rear bar rate (or decrease front bar rate) then you increase the cars propensity to oversteer. When you make an emergency maneuver to avoid a deer, road debris, etc... you can cause the car to snap oversteer due to the insane rear bar rate and relatively low or non existent front bar rate. While an ARB helps a car maintain traction in a straight line by keeping both rear tires loaded, it will prevent the rear from gripping during a turn. This problem can be made even worse when you run pizza cutter tires up front.

As long as you take the time to learn the car, figure out how it reacts when you do certain things, and understand that the car may get away from you during an emergency maneuver, you'll probably be fine. Tons and tons of my customers run no FSB with a rear ARB on daily driven cars, I just like people to understand what they're getting themselves into. Be smart, don't drive like a jackass, maintain safe distance, and keep your eyes peeled. You'll be fine.

This was the exact information I was looking for, how it would react under emergency situations.
So pt 2 of the is survey, lol. How much is gained once you have drag springs and loosing the front sway bar, any back to back comparisons? (I'm fine with disconnecting a link at the track, just curious at the the amount it might cut off a 60' time)
 
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lindertw

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my $0.02...

front sway bar (and bracket) removed, lightweight radiator support in it's place. I drive like a little old lady on the street so I've noticed zero difference with it gone.

you can experiment at home. jack up the front of the car with the front sway bar installed/connected and measure the gap between front tire and fender when the tires just leave the ground. disconnect the sway bar and raise the car again - compare the measurements... (note, if you have adj struts, set them to full loose)

rear sway bar replaced with whiteline adjustable piece, set on it's stiffest setting (approx 3.5 times firmer than OEM). this was an experiment with a bolt on piece, ran it for a year prior to BMR releasing their version of a full bolt on arb. No ill effects when daily driving, kept the front level on launch. All bolt in, just over $200, and only weighs 4 lbs more than the OEM bits I took off. An ok experiment as far as I'm concerned.

20150919_161845_zpsntczyp8x.jpg


older cobra jet drag springs, single adj front struts (set to full loose), single adj rear shocks (set to +7 clicks). launch at 6500 rpm and hang on :) (UCA/LCA location play a part as well).

weight_transfer_zpsywpkfu2w.jpg


lastly, try a shorter accessory belt that bypasses the power steering pump at the track. takes just a few minutes to swap it out before you make a pass, and swap it back before you drive home. It was worth a tenth with my setup. Very easy to drive w/o power steering on slicks and skinnies.

0851F150-D81B-44DC-AB8B-816479BB49E1-738-0000019F696538B0_zps1073cab6.jpg


good luck and post up the results!
 

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