Suspension Geometry & Weight Distribution
Thread Starter
Launching!
Joined: May 2012
Posts: 209
Likes: 1
From: NC
Suspension Geometry & Weight Distribution Would like to really bat a few ideas around with others and see what technical data is out there - ive been chewing and researching on this for months and cannot seem to come up with any tangible connections as to why some spring-rate, wheelbase, and weight distribution setups simply work better or worse than others. Similarly, how some people have very similar setups and wheelbases but one launches like a rocket and the other requires a wheelie bar and serious driver abilities.
Suspension geometry ranges from ladder bars to 4 links. Ideally getting the rear to squat is what hooks at the track - but i've even seen it on 275 tires and just dont get it.
Weight over the nose of a vehicle, wheelbase, soft or hard launches with gearing, transmission selection/boost control, lightweight tube chassis frames, solid box frames, and many other theories or applications of design exist, but i do not see a real connection that deals with one or the other that directly effects the hook at the track as a single variable. Elimination of frame twist and other things come into play as well.
I know i have heard talk of finding the center point of balance in the car and adjusting it, but adjust to what reference? Tire or calculated center of gravity? What other variables exist? Literature to recommend for reading? Is it simply the knowledge of tuning coil rates?
Tim Lynch's team has always pushed the limit. Would really like to know what theory and knowledge exists on the subject and what to look out for or tune for with a build.
Suspension geometry ranges from ladder bars to 4 links. Ideally getting the rear to squat is what hooks at the track - but i've even seen it on 275 tires and just dont get it.
Weight over the nose of a vehicle, wheelbase, soft or hard launches with gearing, transmission selection/boost control, lightweight tube chassis frames, solid box frames, and many other theories or applications of design exist, but i do not see a real connection that deals with one or the other that directly effects the hook at the track as a single variable. Elimination of frame twist and other things come into play as well.
I know i have heard talk of finding the center point of balance in the car and adjusting it, but adjust to what reference? Tire or calculated center of gravity? What other variables exist? Literature to recommend for reading? Is it simply the knowledge of tuning coil rates?
Tim Lynch's team has always pushed the limit. Would really like to know what theory and knowledge exists on the subject and what to look out for or tune for with a build.
Thread Starter
Launching!
Joined: May 2012
Posts: 209
Likes: 1
From: NC
I would believe a lower center of gravity would help as well - getting your car as low as possible and removing top-heavy components could make it handle better as far as top end response and stability might be concerned - just something else that comes to mind.
Topic does not seem to get much love - its black magic knowledge
Topic does not seem to get much love - its black magic knowledge
Thread Starter
Launching!
Joined: May 2012
Posts: 209
Likes: 1
From: NC
Removing the front sway bar in favor for the rear sway bar is a must it seems?
I also know a common trick is to put in a 1x1x1 steel bracing bar at the front of unibodies - it is something i have seen in monte's and g bodies a few times. I wonder the difference it would make compared to without or with the front SB?
And there is another topic in itself - unibodies versus solid frame platforms for certain ET's
I also know a common trick is to put in a 1x1x1 steel bracing bar at the front of unibodies - it is something i have seen in monte's and g bodies a few times. I wonder the difference it would make compared to without or with the front SB?
And there is another topic in itself - unibodies versus solid frame platforms for certain ET's
TECH Addict
Joined: Sep 2009
Posts: 2,481
Likes: 5
From: PA/MD
A huge thing you could do is subframe connectors and a 12pt cage...that would make a unibody insanely stiff. When I started to do the 4 link in my 04 GTO I ran 2x3 tubing for the main chassis, then ran a modified 12pt + cage to make the car stiff as possible.
Also set the four link pointing up from under the axle towards the center of the car...this way it pushes the tires into the ground when it launches.
Also set the four link pointing up from under the axle towards the center of the car...this way it pushes the tires into the ground when it launches.
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?
Pouria Savadkouei
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Launching!
Joined: Sep 2011
Posts: 206
Likes: 0
some x275 cars ive seen and worked on have had a 10 to 15% more weight in the front. we can hit the tire harder and allow the car to 60ft better.. let me tell u though it doesnt always work that way.. every track is different and to be honest we change it alot.. it all depends on track conditions.. you go to a track that has alot of bite we shift weight forward and hit it harder. less bite we move it towards the rear and take some power out if its needed to keep from going otb.. as someone stated b4 u want the body to lift and force the rear end into the ground... squating is the old school way of getting a carr to work. not saying its completely wrong its just not how people are getting these cars to 60ft as hard as they are now adays
Would like to really bat a few ideas around with others and see what technical data is out there - ive been chewing and researching on this for months and cannot seem to come up with any tangible connections as to why some spring-rate, wheelbase, and weight distribution setups simply work better or worse than others. Similarly, how some people have very similar setups and wheelbases but one launches like a rocket and the other requires a wheelie bar and serious driver abilities.
Suspension geometry ranges from ladder bars to 4 links. Ideally getting the rear to squat is what hooks at the track - but i've even seen it on 275 tires and just dont get it.
Weight over the nose of a vehicle, wheelbase, soft or hard launches with gearing, transmission selection/boost control, lightweight tube chassis frames, solid box frames, and many other theories or applications of design exist, but i do not see a real connection that deals with one or the other that directly effects the hook at the track as a single variable. Elimination of frame twist and other things come into play as well.
I know i have heard talk of finding the center point of balance in the car and adjusting it, but adjust to what reference? Tire or calculated center of gravity? What other variables exist? Literature to recommend for reading? Is it simply the knowledge of tuning coil rates?
Suspension geometry ranges from ladder bars to 4 links. Ideally getting the rear to squat is what hooks at the track - but i've even seen it on 275 tires and just dont get it.
Weight over the nose of a vehicle, wheelbase, soft or hard launches with gearing, transmission selection/boost control, lightweight tube chassis frames, solid box frames, and many other theories or applications of design exist, but i do not see a real connection that deals with one or the other that directly effects the hook at the track as a single variable. Elimination of frame twist and other things come into play as well.
I know i have heard talk of finding the center point of balance in the car and adjusting it, but adjust to what reference? Tire or calculated center of gravity? What other variables exist? Literature to recommend for reading? Is it simply the knowledge of tuning coil rates?
http://www.hotrod.com/techarticles/c...tire_traction/
not just the chassis itself plays a role... the type of differential, aero, etc all come into play.
TECH Addict
Joined: Sep 2009
Posts: 2,481
Likes: 5
From: PA/MD
I did not weigh my whole irs and all its parts, but the 9" is lighter than the old irs...in my case I'm not completely sure how you would calculate the change, because 90% of the irs system was part of the unibody and sprung weight, whwre the 9" is unsprung weight.
it also transferred weight differently than a solid axle
TECH Addict
Joined: Sep 2009
Posts: 2,481
Likes: 5
From: PA/MD
TECH Addict
Joined: Sep 2009
Posts: 2,481
Likes: 5
From: PA/MD
Gutted the car and still trying to finish the wiring do I can drive it out of the garag lol
I built a full tube chassis, moved the engine back 12.5"s, dropped ton of weight, and went from "stock" size tires to a set of 15x 18" wheels and 33-21.5 15s in the back, so I hope to be able to launch strait and put it hard on the wheelie bars.
I built a full tube chassis, moved the engine back 12.5"s, dropped ton of weight, and went from "stock" size tires to a set of 15x 18" wheels and 33-21.5 15s in the back, so I hope to be able to launch strait and put it hard on the wheelie bars.
TECH Addict
Joined: Sep 2009
Posts: 2,481
Likes: 5
From: PA/MD
