BMR adjustments
06-04-2008, 11:39 AM
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BMR adjustments Ok this was brought up in another thread and got me wondering.
On the BMR torque arm front mount relocation to trans crossmember you have multiple holes to choose from, moving the torque arm up and down. This will cause you to move your center of gravity. Witch way moves it front and back?
Also on the relocation brackets for the LCA's what hole is better to use the lower one or the higher one (I guess what I'm asking it what does it change)?
On the BMR torque arm front mount relocation to trans crossmember you have multiple holes to choose from, moving the torque arm up and down. This will cause you to move your center of gravity. Witch way moves it front and back?
Also on the relocation brackets for the LCA's what hole is better to use the lower one or the higher one (I guess what I'm asking it what does it change)?
06-04-2008, 12:15 PM
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Ok this was brought up in another thread and got me wondering.
On the BMR torque arm front mount relocation to trans crossmember you have multiple holes to choose from, moving the torque arm up and down. This will cause you to move your center of gravity. Witch way moves it front and back?
.
Also on the relocation brackets for the LCA's what hole is better to use the lower one or the higher one (I guess what I'm asking it what does it change)?
On the BMR torque arm front mount relocation to trans crossmember you have multiple holes to choose from, moving the torque arm up and down. This will cause you to move your center of gravity. Witch way moves it front and back?
It only moves it up and down not front to back. The higher up you move the tip of the torque arm the quicker and harder the rear suspension reacts at launch
Also on the relocation brackets for the LCA's what hole is better to use the lower one or the higher one (I guess what I'm asking it what does it change)?
06-04-2008, 01:29 PM
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it moves the center of gravity of the car from front and back when you adjust the front mount up and down right?
Last edited by BlackSS2001; 06-04-2008 at 01:56 PM.
06-04-2008, 09:13 PM
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Actually, it changes the Instant Center of the rear suspension, not the center of gravity of the car.
The instant center is a 2-dimensional measurement. When you mount the torque arm using the highest holes, you move the instant center forward and up. When you mount the torque arm using the lowest holes, you move the instant center back and down.
Unfortunately, the best instant center location depends on a number of factors. For example, a stick car usually likes a lower and longer (farther from the rear axle housing centerline) instant center while an auto trans car likes a higher and shorter instant center. Also, the bigger the tire, the longer the instant center should be.
How tight is the torque converter? Do you launch with a trans brake? How stiff are the shocks set in compression? How stiff are the shocks set for extension? All these factors determine the best instant center location.
Fortunately, the BMR Torque Arm Relocation Bracket has multiple hole settings, so you can tune your suspension at the track.
The instant center is a 2-dimensional measurement. When you mount the torque arm using the highest holes, you move the instant center forward and up. When you mount the torque arm using the lowest holes, you move the instant center back and down.
Unfortunately, the best instant center location depends on a number of factors. For example, a stick car usually likes a lower and longer (farther from the rear axle housing centerline) instant center while an auto trans car likes a higher and shorter instant center. Also, the bigger the tire, the longer the instant center should be.
How tight is the torque converter? Do you launch with a trans brake? How stiff are the shocks set in compression? How stiff are the shocks set for extension? All these factors determine the best instant center location.
Fortunately, the BMR Torque Arm Relocation Bracket has multiple hole settings, so you can tune your suspension at the track.
06-04-2008, 11:02 PM
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Well as it is now I set it as low as I can go (in the middle) My Y pipe is in the way 
I have a stick car stock shocks LCA and the relocations. the adj torque arm and mount. thats really it.
I have a stick car stock shocks LCA and the relocations. the adj torque arm and mount. thats really it.
06-04-2008, 11:43 PM
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We normally recommend that you start by mounting it in the middle and then testing it up and down at the dragstrip.
If you mount the torque arm in the upper holes, you're more likely to lift the front wheels off the ground when you launch. Good fun!!
If you are interested in the technical aspects of suspensions, you should read an article from last month's Race Pages magazine called "The Science of Suspension". Race Pages is the NMRA magazine, but the article is about suspensions in general (not just Ford suspensions).
The article has some great quotes from BMR and other leading suspension companies. I'll post a copy of the article on the front page of the BMR website on Thursday morning in case you would like to read it.
If you mount the torque arm in the upper holes, you're more likely to lift the front wheels off the ground when you launch. Good fun!!
If you are interested in the technical aspects of suspensions, you should read an article from last month's Race Pages magazine called "The Science of Suspension". Race Pages is the NMRA magazine, but the article is about suspensions in general (not just Ford suspensions).
The article has some great quotes from BMR and other leading suspension companies. I'll post a copy of the article on the front page of the BMR website on Thursday morning in case you would like to read it.
