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9.73sec 1.41 60ft on SB2.2 N/A help!!!

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Old 04-02-2008, 03:46 AM
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Default 9.73sec 1.41 60ft on SB2.2 N/A help!!!

Dear all,
My Camaro has all BMR suspensions.
Its run 9.73sec 1.41 60ft on SB2.2 N/A with out trans brake. But I am facing some problems.
The car wheels stand up 2 times during the run how can I fix this (rear tire pressure 10 psi) and there are wheel hop (wheel shake) how can I fix it too?? And how can I adjust QA1 12 way all corner (I am using 6 adjustments in front and rear)??

Best regards
Mohammed Buchiri
Snipers Racing Team
Old 04-02-2008, 05:33 AM
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Are you running a drag radial or a bias bly tire? Tire pressure seems a little low. Do you have travel limiters on the car? If not, putting a set on the front to hold it down will solve the wheelstanding issues, should keep the nose alot lower. Shock adjustments vary from one person's car to the next, only way to really find out what works is to make a run, even just the first 600 feet just to get a feel for how the car leaves, change the settings and repeat.


It sounds like you need to add some air pressure, should help eliminate some of the tire shake, and if the car starts 60 footing worse, loosen the front shocks some to get it back. Most people with 12 way shocks usually end up between 2 to 4 on the front, where you have the rears is probably about right.
Old 04-02-2008, 06:32 AM
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Originally Posted by JL ws-6
Are you running a drag radial or a bias bly tire? Tire pressure seems a little low. Do you have travel limiters on the car? If not, putting a set on the front to hold it down will solve the wheelstanding issues, should keep the nose alot lower. Shock adjustments vary from one person's car to the next, only way to really find out what works is to make a run, even just the first 600 feet just to get a feel for how the car leaves, change the settings and repeat.


It sounds like you need to add some air pressure, should help eliminate some of the tire shake, and if the car starts 60 footing worse, loosen the front shocks some to get it back. Most people with 12way shocks usually end up between 2 to 4 on the front, where you have the rears is probably about right.
• Running a bias bly tire 28”
• I just order travel limiters.

For now I will increase the air pressure. Fix the travel limiters and set up the 12 way. shocks 4 on the front 6 on the rear.
I will post the result after I run the car on 17/04/08 test & tune day.
Old 04-02-2008, 08:02 AM
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Tighten the rear shocks up, air up the rear tires. This will help the tire shake.

Tighten the front shocks all the way down and see how it does. Lower the launch RPM also will help.


David
Old 04-02-2008, 08:20 AM
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Originally Posted by FASTFATBOY
Tighten the rear shocks up, air up the rear tires. This will help the tire shake.

Tighten the front shocks all the way down and see how it does. Lower the launch RPM also will help.


David
Thanks FastFatBoy
I use to start with 2800RPM but I will flash it from 1500RPM this time
and i will Tighten the front shocks all the way down + up air tires
And we will see how it will run .
Old 04-02-2008, 09:44 AM
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Originally Posted by snipers
• Running a bias bly tire 28”
• I just order travel limiters.

For now I will increase the air pressure. Fix the travel limiters and set up the 12 way. shocks 4 on the front 6 on the rear.
I will post the result after I run the car on 17/04/08 test & tune day.
That will work great and make small adjustments from there. I run MT 28/ 10.5 slicks and run them at 12 to 13.5psi on a 3685 racewight.

Adjusting the front shocks to 12(fully tight) is not going to work on any dragstrip!!
Even if it has lots and lots and lots of VHT on the track.
Old 04-02-2008, 09:49 AM
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I don't like running slicks lower than 12psi cold, and 14 psi drive nice down the track. When I've run 10psi the car has had a tendency to feel floaty on the big end. I have travel limiters on my Formula, only lifted the fronts 6 inches on the 1.35 9.44@144mph pass.
Old 04-02-2008, 11:29 AM
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Originally Posted by Caveman
That will work great and make small adjustments from there. I run MT 28/ 10.5 slicks and run them at 12 to 13.5psi on a 3685 racewight.

Adjusting the front shocks to 12(fully tight) is not going to work on any dragstrip!!
Even if it has lots and lots and lots of VHT on the track.
i run goodyear 28/10 sliks on 3200.what do you think of going to 14osi.
i did not Adjust front shocks to 12(fully tight) i Adjust it to 6 fron and 6 rear?!
Old 04-02-2008, 12:03 PM
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Originally Posted by Pro Stock John
I don't like running slicks lower than 12psi cold, and 14 psi drive nice down the track. When I've run 10psi the car has had a tendency to feel floaty on the big end. I have travel limiters on my Formula, only lifted the fronts 6 inches on the 1.35 9.44@144mph pass.
thanks Jon for you reply,
i dont have travel limiters on my car as you can see the pic but as i say befor the car stand up2 times???this my problem??

Old 04-02-2008, 12:36 PM
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Originally Posted by Caveman
That will work great and make small adjustments from there. I run MT 28/ 10.5 slicks and run them at 12 to 13.5psi on a 3685 racewight.

Adjusting the front shocks to 12(fully tight) is not going to work on any dragstrip!!
Even if it has lots and lots and lots of VHT on the track.

Ive been on the bumper twice with the front shocks set at 12 with a 1.29 60'.

If you want the most adjustability, go with a double adjustable shock. That way you can adjust how the shock extends and compresses. A single adjustable shock only does compression as far as know.
Old 04-02-2008, 12:53 PM
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Originally Posted by SMKN TA 95
Ive been on the bumper twice with the front shocks set at 12 with a 1.29 60'.
I didn't think that could be done with the shocks set that stiff. The one time I stood my car up on the rear bumper I had the front shocks set at 3 and the limiters had 4.5" of travel.

Nice looking car by the way
Old 04-02-2008, 12:57 PM
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Originally Posted by Caveman
I didn't think that could be done with the shocks set that stiff. The one time I stood my car up on the rear bumper I had the front shocks set at 3 and the limiters had 4.5" of travel.

Nice looking car by the way

Yes, unfortunately it can be done That was also done with the front limiters set for 1.5" of suspension travel too

Limiters aren't a cure all for wheel stands thats for sure.
Old 04-02-2008, 12:58 PM
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The travel limiters are a no-brainer at your ET level, they will help. I was told not to let teh front tires hang more than three inches on the launch. I don't know much about double adjustable shocks but having the ability to double adjust shocks sounds great. I'd run the front QA1's at 2 to start and then go down if the car is violent. I run the rears at 6/6 and fronts at 1/1 and only once in a while have I been able to tighten up the fronts, most of my local tracks need all the help I can add to 60ft.
Old 04-02-2008, 01:00 PM
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Adding more air can also make the car stand more, from the launch pic you need to adjust your anti roll bar, like said before stiffen the rear shock, stiffen the front shock, what's your instant center at?

You could soften the hit to the tire that should also help some, but I would only do one thing at a time and see how each one reacts, also take baseline settings of where everything is so if you change too much and screw it up you have a starting point.

Start a log book of your settings and the results of each pass.
Old 04-02-2008, 01:52 PM
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Originally Posted by RAGENZ28
Adding more air can also make the car stand more, from the launch pic you need to adjust your anti roll bar, like said before stiffen the rear shock, stiffen the front shock, what's your instant center at?

You could soften the hit to the tire that should also help some, but I would only do one thing at a time and see how each one reacts, also take baseline settings of where everything is so if you change too much and screw it up you have a starting point.

Start a log book of your settings and the results of each pass.
Thanks RAGENZ28,
You are 100% right Air can make the car stand up more i will solve this to by add sheet in the front bumper.
For the anti roll bar i will look at it too.

Log book will help too
Thanks a lot for your reply
Old 04-02-2008, 04:31 PM
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Originally Posted by Caveman
That will work great and make small adjustments from there. I run MT 28/ 10.5 slicks and run them at 12 to 13.5psi on a 3685 racewight.

Adjusting the front shocks to 12(fully tight) is not going to work on any dragstrip!!
Even if it has lots and lots and lots of VHT on the track.
Yes it will work, what exactly do you think limiters do?The car has enough bite, all it will do is slow extension waaaayyyyy down in the front.

I have seen cars stand up with the shocks on full stiff in the front. If it spins, thats good...he can loosen the fronts until he finds a happy medium. Thats why you buy the adjustable shocks. AT least this way it wont come crashing down from a wheelstand.

I would run the rears full stiff if you have a wheelhop/tire shake issue. OR tighten them up each pass until it stops. BUT keep in mind tire shake DESTROYS drivetrain parts, and does it with a quickness.


I think your anti-roll bar is set ok, the angle of the pic makes the car look funny. The gap between the tire and right rear fender looks ok and both front tires are off the ground an equal amount.

DOes the car come up any higher than the pic that you have on this post? If not ride it out.


Keep us updated on how it goes.

BTW are your tires screwed to the rim? If not they need to be.

David

Last edited by FASTFATBOY; 04-02-2008 at 04:37 PM.
Old 04-02-2008, 04:37 PM
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Originally Posted by FASTFATBOY
Yes it will work, what exactly do you think limiters do?The car has enough bite, all it will do is slow extension waaaayyyyy down in the front.

I have seen cars stand up with the shocks on full stiff in the front. If it spins, thats good...he can loosen the fronts until he finds a happy medium. Thats why you buy the adjustable shocks. AT least this way it wont come crashing down from a wheelstand.

I would run the rears full stiff if you have a wheelhop/tire shake issue. OR tighten them up each pass until it stops. BUT keep in mind tire shake DESTROYS drivetrain parts, and does it with a quickness.


Keep us updated on how it goes.


BTW are your tires screwed to the rim? If not they need to be.

David
thanks a lot David for you
yes i have screw tire rim but i will but them soon for my next run
thanks agin for you info
Old 04-02-2008, 09:33 PM
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Car is twisted leaving. You have to pre load the passenger side to correct it.
I used to run the Goodyear D3's. I found they worked best at 12 psi.
1.41 60' is a bit soft for that ET. I personally don't like to bring the rpms up off the footbrake, it preloads the suspension and in my opinion doesn't let it work right. Either go off idle or the transbrake.
I found the rears worked beat set at 8, the fronts vary but don't be afraid to pull the wheels a couple of feet on these cars to get it to 60'.
Once you get the 60' down the lifting will correct itself because the car will carry through smoothly and set her down easy.
This is a video of my car, I have wheelie bars and limiters, also dual rear airbags which you may wind up needing to get her to leave hard, our times are similar.
I believe the first pass on this vid was a 1.32 60' and the 2nd pass was a 1.29.
http://www.youtube.com/watch?v=KVdBZk5Y3s4

Mark

By the way, your car looks NASTY! I like it!
Old 04-03-2008, 04:03 PM
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Originally Posted by tektrans
Car is twisted leaving. You have to pre load the passenger side to correct it.
I used to run the Goodyear D3's. I found they worked best at 12 psi.
1.41 60' is a bit soft for that ET. I personally don't like to ubring the rpms p off the footbrake, it preloads the suspension and in my opinion doesn't let it work right. Either go off idle or the transbrake.
I found the rears worked beat set at 8, the fronts vary but don't be afraid to pull the wheels a couple of feet on these cars to get it to 60'.
Once you get the 60' down the lifting will correct itself because the car will carry through smoothly and set her down easy.
This is a video of my car, I have wheelie bars and limiters, also dual rear airbags which you may wind up needing to get her to leave hard, our times are similar.
I believe the first pass on this vid was a 1.32 60' and the 2nd pass was a 1.29.y
http://www.youtube.com/watch?v=KVdBZk5Y3s4

Mark

By the way, your car looks NASTY! I like it!

thanks Mark for you reply
i am runing Goodyear D3's 28-10-15 but i set them on 10 but i will try 12 to 14psi.

for bring the rpms i speek with coan and they say i should flash the rpm at start!!!! as you say and i will do that next time.
i am not afraid to pull the wheels but as i say the car stand 2 time up-down-up-down
BTW you car run wooooooooooooooooow
Old 04-03-2008, 07:41 PM
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Nice to see you here Mod.

Your brakes will be on the way when my bank figures out what Bahraini Dinars are..
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