Are you square? Is your suspension & rear end square? Here is a video on the string method you can use to confirm if your drag racing chassis, or any chassis for that matter, is square. If you are centering your rear end based on measurements to your chassis, then please take the time to confirm the chassis is square. It can save you a bunch of time from chasing rabbits! Special shoutout to Mike Lucas "Seattle Mike" for reaching out and supplying this String Method drawing, along with steps and notes. We have used a variant of this method in our shop as long as I can remember, dad would be drawing on the floor with markers and chalk and measuring. For that matter, every chassis he fabricated, it was completely drawn out on the garage floor in full scale.
Best thing about this method is how simple it is for everyday use. Guy I know that builds 4 or so cars a year uses string, a good level, plumb bobs and known measurements, that is it. They all go straight. It makes life at the track so much easier since a slight tweak accounts for nearly all conditions, two or three clicks on shocks at one end is a lot and moving up/down a hole is HUGE on those cars. Thanks for the ongoing videos.
Many passenger cars and trucks have an offset drivetrain centerline for different reasons and when you convert them into a race car you can re-engineer them, in most cases, so that the driveline and chassis centerlines are the same but this difference in as built configuration should be defined and taken into account when setting a car up like this so that you are using the true chassis centerline for wheel location. Thank you for another great video....
More great advice Kevin' Wilson ! Im a carpebter framer by trade so ive got a bosch lazer level that shoots dead strait lines on the floor with a perpendicular line to it . Working out awesome in this application . Squared up about 10 thousand walls and buildings but never a car lol Fun fun here . You might want to look into one of these . Cut the job time literally by a couple hundred percent without a doubt
I used this method. 4 link x member is off square 7/16. The 4 link bars are adjusted about 3/8 longer on the left side to compensate. Next I’ll see if the car launches straight.
@@KevinWilsonSBC It did help thanks. The car is going straight. I’ll eventually get around to redoing the c member / rear clip. I was thinking that a string line from front to rear and a 24” framers square off the line would also come to the same conclusion.
ou man you are a genius in explaining tech . I have a 75 monza for road racing . Can I improve traction replacing the torque arm with a good set up 4-link ?
I am using all caltrac components as you suggested on my S10. Split mono , sliders , and cal trac bars. Would leaf spring setup benefit from this procedure? As always THANK YOU for your time and willingness to share your experience and willingness to be humble to share others experience. THANK YOU!!!!!!
Exactly what I wanted to see. I think my urethane bushed 4 link cross member is welded in 1/4” off square in an old back half Chevelle chassis. I’ll check it using this method.
@@AustinBoil I’ll post up what I find. I plumb bobbed off the front control arm mounts to square it up and I don’t think those old chassis were ever straight to begin with especially if ever in an accident. The Alston urethane pro street links especially need to be straight or they bind and wear out quick. Spherical rod ends have a bit more adjustment for rear steer. Street / strip builds are a compromise thing.
Kevin nice video. The only issue I see with it is the method you used for determining the chassis center line. By using the center line of the crank or the center of the diff housing you don't account for a frame that's possibly not straight or tweaked. The car always drives off of the suspension location. A better place to drop the plum bobs are from the front and rear control arm mounting locations. This way if the frame is not straight it wont matter. The car will be driving off of the suspension. I learned that from Dave Morgan. Good luck with your car.
You DO NOT use the crank or center of rear end housing. The instruction sheet does not say to use those points as the starting point. You want the centerline of the CHASSIS. Many chassis builders actually put a mark or "V" where the exact centers are. This method is used to determine if the 4 link brackets & everything else including wheelie bars is exactly centered to the chassis. If one is off then all measurements in the rear will be off compared to the front etc. If you measure from the centerline out front & rear & they are all equal then the chassis will be square.
Good Video Kevin . Pretty cool method . The problem I see with a lot of average race cars are unibody with an off set drive train so you have to measure off of the body somewhere to get your center marks . I’m having issues with wheel well gap ahead of the tire right now . I just did Merillat boxes and a converted to coil overs along with a ton of new mods in a mustang . I’m going to find center and measure from the axle centerline and brackets in the car in a triangle to see where the problem is if any . I have dropped plumbs off of body jig points everywhere and everything seems perfect except the wheel well gap and the k frame being in crooked. Measuring in an x or triangle to the center point seems way easier than trying to make these arcs on the floor but I’d like to try both . Thanks
Kevin, Been having wander problems in my racer. Especially on the big end of the track. It’s a 34 Ford replica, home built , 440 mopar, Torqueflite , Dana 60, 4 link w/ track locator. QA-1 DD 501 shocks. Front end is Mustang 2 alignment is 0* camber , 8*castor , 1/8” toe , . I’ve done everything with the front end to try to cure this I’ll handling problem but nothing seems to help. after watching this video and following the instructions I’ve found the rear ending is/was 1/4” cockeyed in the chassis. Do you think this 1/4” could be causing rear steer enough to contribute or actually cause my wandering problem.? I surly enjoy your videos and appreciate your help. Thank you Don Berry
Don, thanks for leaving a comment. This is likely beyond troubleshooting on a YT comment. Checkout my services at samsonperformance.com/services.html and let's go from there. Definitely use my email and we can get your wandering problem addressed. Depending on if the 1/4" is at the brackets or axle ends it can definitely cause issues. Go fast, go straight! Be SAFE!!
Thanks Kevin, I’ll do my best to get some good videos of the launch as well as the full run . Maybe you can get a better idea then of what’s going on . Thanks again, see you soon Don Berry
Michigan Muscle car garage thanks so much for your comments! So sorry for late response. Still digging out after getting dad back on his feet. Shoot me an email if I can help in anyway. Go fast, go straight! Be Safe!!
@@KevinWilsonSBC Welcome Kev, looking forward to more suspension setup/theory content! Especially any kind of information/theory on no prep. Thanks again Kev 🤘🏼😁🤙🏼
Hello Kevin. I have been watching all ur 4 link videos trying to learn something. I have a 5th gen camaro and I bought a 9in Ford with a 4 link. I'm trying to get it set up and the upper 4 link bars are messing with me. They are not strait forward so im having an issue finding the instant center and anti squat line. Think u could help me out.
Travis Davis thanks so much for your comments! Shoot me as much info as you can, along with pics to samsalignmentsc@gmail.com and I will do what I can in between everything else going on. Go fast, go straight! Be Safe!!
I don't think video helps me much. I removednrear axle on my s10 that's bagged. Problem I'm having I didn't mark center at any angle so axle is sitting more to passenger side. What can I do to fix it
Just follow these steps in detail step by step. Those arcs being drawn off of the string lined plumb bobs are the key to establishing the most correct reference. I know you may feel like you have painted yourself in a corner. This will help you establish your references to check from.
Are you square? Is your suspension & rear end square? Here is a video on the string method you can use to confirm if your drag racing chassis, or any chassis for that matter, is square. If you are centering your rear end based on measurements to your chassis, then please take the time to confirm the chassis is square. It can save you a bunch of time from chasing rabbits!
Special shoutout to Mike Lucas "Seattle Mike" for reaching out and supplying this String Method drawing, along with steps and notes. We have used a variant of this method in our shop as long as I can remember, dad would be drawing on the floor with markers and chalk and measuring. For that matter, every chassis he fabricated, it was completely drawn out on the garage floor in full scale.
Best thing about this method is how simple it is for everyday use. Guy I know that builds 4 or so cars a year uses string, a good level, plumb bobs and known measurements, that is it. They all go straight. It makes life at the track so much easier since a slight tweak accounts for nearly all conditions, two or three clicks on shocks at one end is a lot and moving up/down a hole is HUGE on those cars.
Thanks for the ongoing videos.
Thank you so much for sharing this method being a welder fabricator definitely aply this method to many projects
Kevin I would like very much to speak to you for some recommendations how can I get in touch with you thank you,Dave
Awesome job kevin. Cant get enough of these videos. You lay everything down in a way I understand.
I appreciate the kind words and I enjoy doing the videos! Go Fast, go straight! Be Safe!
Many passenger cars and trucks have an offset drivetrain centerline for different reasons and when you convert them into a race car you can re-engineer them,
in most cases, so that the driveline and chassis centerlines are the same but this difference in as built configuration should be defined and taken into
account when setting a car up like this so that you are using the true chassis centerline for wheel location. Thank you for another great video....
Yes!! Good info and thanks for taking the time to comment! Go Fast, go straight! Be Safe!
More great advice Kevin' Wilson ! Im a carpebter framer by trade so ive got a bosch lazer level that shoots dead strait lines on the floor with a perpendicular line to it .
Working out awesome in this application . Squared up about 10 thousand walls and buildings but never a car lol
Fun fun here .
You might want to look into one of these . Cut the job time literally by a couple hundred percent without a doubt
I never even thought of that!!! Fantastic idea and thank-you for sharing!!! Go fast, go straight! Be SAFE!
I used this method. 4 link x member is off square 7/16. The 4 link bars are adjusted about 3/8 longer on the left side to compensate. Next I’ll see if the car launches straight.
General Sixty thanks so much for your comments! Hope it helped!!! Go fast, go straight! Be Safe!!
@@KevinWilsonSBC It did help thanks. The car is going straight. I’ll eventually get around to redoing the c member / rear clip. I was thinking that a string line from front to rear and a 24” framers square off the line would also come to the same conclusion.
Excellent tutorial. Thank you!!! 👍👍👍
Great job Kevin, nailed it.
Thank-you!!! Go Fast, go straight! Be Safe!
Can you do a vid on chassis bracing? Stiffer the better?
Nice explanations!
Great Video kevin
Thanks man ive been trying to figure square on this S10 and this makes complete sense to me thanks man
roger paul ll thanks so much for your comments! Good to hear! Go fast, go straight! Be Safe!!
@11:04 I hope everyone else realized Kevin's transformation at this point of the video haha!
kevinnagle thanks so much for your comments and supporting this channel! I needed that. Go fast, go straight! Be Safe!!
Kevin Wilson
ou man you are a genius in explaining tech . I have a 75 monza for road racing . Can I improve traction replacing the torque arm with a good set up 4-link ?
I am using all caltrac components as you suggested on my S10. Split mono , sliders , and cal trac bars. Would leaf spring setup benefit from this procedure? As always THANK YOU for your time and willingness to share your experience and willingness to be humble to share others experience. THANK YOU!!!!!!
Yes it will, any chassis will. Go fast, go straight! Be SAFE!!
Exactly what I wanted to see. I think my urethane bushed 4 link cross member is welded in 1/4” off square in an old back half Chevelle chassis. I’ll check it using this method.
Let us know what you find if you would. This method has fixed a lot of cars that guys struggled with & could never get to go straight.
Glad this could help you!!! Keep us posted. Go Fast, go straight! Be Safe!
@@AustinBoil I’ll post up what I find. I plumb bobbed off the front control arm mounts to square it up and I don’t think those old chassis were ever straight to begin with especially if ever in an accident. The Alston urethane pro street links especially need to be straight or they bind and wear out quick. Spherical rod ends have a bit more adjustment for rear steer. Street / strip builds are a compromise thing.
can't wait to try this... thanks. Great content
Good to hear, Todd!! Keep me posted. Go Fast, go straight! Be Safe!
Great Video, one question, where can I get a copy of the squaring procedure you used in this video.
I will work on getting this linked out on the web here shortly!!! Thanks! Go Fast, go straight! Be Safe!
Kevin nice video. The only issue I see with it is the method you used for determining the chassis center line. By using the center line of the crank or the center of the diff housing you don't account for a frame that's possibly not straight or tweaked. The car always drives off of the suspension location. A better place to drop the plum bobs are from the front and rear control arm mounting locations. This way if the frame is not straight it wont matter. The car will be driving off of the suspension. I learned that from Dave Morgan. Good luck with your car.
Good info, Ralph!!! Go Fast, go straight! Be Safe!
You DO NOT use the crank or center of rear end housing. The instruction sheet does not say to use those points as the starting point. You want the centerline of the CHASSIS. Many chassis builders actually put a mark or "V" where the exact centers are. This method is used to determine if the 4 link brackets & everything else including wheelie bars is exactly centered to the chassis. If one is off then all measurements in the rear will be off compared to the front etc. If you measure from the centerline out front & rear & they are all equal then the chassis will be square.
Good Video Kevin . Pretty cool method . The problem I see with a lot of average race cars are unibody with an off set drive train so you have to measure off of the body somewhere to get your center marks . I’m having issues with wheel well gap ahead of the tire right now . I just did Merillat boxes and a converted to coil overs along with a ton of new mods in a mustang . I’m going to find center and measure from the axle centerline and brackets in the car in a triangle to see where the problem is if any . I have dropped plumbs off of body jig points everywhere and everything seems perfect except the wheel well gap and the k frame being in crooked. Measuring in an x or triangle to the center point seems way easier than trying to make these arcs on the floor but I’d like to try both . Thanks
What method do you use to find rearend centerline?
Kevin,
Been having wander problems in my racer. Especially on the big end of the track. It’s a 34 Ford replica, home built , 440 mopar, Torqueflite ,
Dana 60, 4 link w/ track locator. QA-1 DD 501 shocks.
Front end is Mustang 2 alignment is 0* camber , 8*castor , 1/8” toe , . I’ve done everything with the front end to try to cure this I’ll handling problem but nothing seems to help.
after watching this video and following the instructions I’ve found the rear ending is/was 1/4” cockeyed in the chassis. Do you think this 1/4” could be causing rear steer enough to contribute or actually cause my wandering problem.?
I surly enjoy your videos and appreciate your help.
Thank you
Don Berry
Don, thanks for leaving a comment. This is likely beyond troubleshooting on a YT comment. Checkout my services at samsonperformance.com/services.html and let's go from there. Definitely use my email and we can get your wandering problem addressed. Depending on if the 1/4" is at the brackets or axle ends it can definitely cause issues. Go fast, go straight! Be SAFE!!
Thanks Kevin,
I’ll do my best to get some good videos of the launch as well as the full run . Maybe you can get a better idea then of what’s going on .
Thanks again, see you soon
Don Berry
Hey Kevin we just bought a new chassis truck having some issues, been watching your videos, maybe we could talk to help get this setup right? Thanks
Michigan Muscle car garage thanks so much for your comments! So sorry for late response. Still digging out after getting dad back on his feet. Shoot me an email if I can help in anyway. Go fast, go straight! Be Safe!!
@10:43 We're chasin' Wabbbits Elmer Fudd
kevinnagle thanks so much for your comments and supporting this channel! LOL. Go fast, go straight! Be Safe!!
Kevin Wilson
@@KevinWilsonSBC Welcome Kev, looking forward to more suspension setup/theory content!
Especially any kind of information/theory on no prep.
Thanks again Kev 🤘🏼😁🤙🏼
Hello Kevin. I have been watching all ur 4 link videos trying to learn something. I have a 5th gen camaro and I bought a 9in Ford with a 4 link. I'm trying to get it set up and the upper 4 link bars are messing with me. They are not strait forward so im having an issue finding the instant center and anti squat line. Think u could help me out.
Travis Davis thanks so much for your comments! Shoot me as much info as you can, along with pics to samsalignmentsc@gmail.com and I will do what I can in between everything else going on. Go fast, go straight! Be Safe!!
@@KevinWilsonSBC sounds great ty. Give me a few days and I'll be in touch. Thanks and God bless
I don't think video helps me much. I removednrear axle on my s10 that's bagged. Problem I'm having I didn't mark center at any angle so axle is sitting more to passenger side. What can I do to fix it
Just follow these steps in detail step by step.
Those arcs being drawn off of the string lined plumb bobs are the key to establishing the most correct reference.
I know you may feel like you have painted yourself in a corner.
This will help you establish your references to check from.
👍👍
👍👍👍
👍👍👍👍