getting Patina closer to being a roadcourse beast i wanted to pull out the Bumpsteer gauge that i normally use for my circle track cars and see how bad my mopar was, and man are mopars hurtin when it comes to bumpsteer
Пікірлер: 59
@raylindberg2120Ай бұрын
automotive engineering professor Chris Birdsong; excellent seminar. one of the best explanations on front end geometry i"ve heard in a long time. you"ve explained what, why and proved your statements. please keep the videos comming
@kikurass322Ай бұрын
A man full of knowledge is a man worth watching. You're a legend Chris. I'd love to turn spanners with you.
@brettemerich3237Ай бұрын
Chris,This is what racing is all about fixing bad designs on old cars and make them work. I guess you got tired of sheet metal work(you made it look too easy,that’s how good you are)Nice video
@MattisgarageАй бұрын
I always remember a scene from original Vanishing Point where Kowalski drives over several bumps and Challenger front wheel flops around...
@georgeparker7409Ай бұрын
A great explanation of an often overlooked science. I was exposed to "BUMP STEER" when we started to mess with the solid axels back in the flathead days. About the time we stated splitting the axel in half to make an "independent suspension". Really started to be sort of around when we began using 55 Chevy front clips. Your explanation was spot on. Many thanks.
@4thdownclownАй бұрын
Chris, thanks for bringing your wealth of racing geometry knowledge to the masses. Thats why this channel kicks ass. I also dont know how you guys live with that heat. Stay frosty dude.
@benjamintresham9649Ай бұрын
Here in Australia we are RHD and the mopar steering is good as the idler arm and steering box are mounted directly off the chassis rails. This keeps the pivot points almost over the top of the torsion bars or lower inner bushings We have A B and C bodies in RHD
@anthonyshelton678624 күн бұрын
thanks for the education makes me wonder what my stuff has for bumpsteer I know one of my cars was pretty bad so the idler pitman being changed was probably why that suddenly got bad
@DeadReckonАй бұрын
If you hooked that rig up to my '83 Dodge D150, that gauge would read "Yes". Factory manual steering slant 6 / 4 speed A-833 short bed, I swapped in a 318. Gutless as the day is long but she's a fun old rig to drive.
@martind701Ай бұрын
Thank you for the teaching moment Chris!
@DennisDulin-cu2flАй бұрын
Chris your the only u tuber that's giving out great information!
@dtengineering1Ай бұрын
Really nice and simple explanations. Cheers
@roycervantes1341Ай бұрын
Yeee Yeee ! ,,,,,love this channel thank you Chris for all the great content, Yeee Yeee!!!👍
@510CurtDawgАй бұрын
Super interesting! I got a lil duster, im always after the handling!! Im gunna have to watch more of your videos
@DennisDulin-cu2flАй бұрын
We need a course on Ackerman!
@dannycurtis1744Ай бұрын
Great video Chris,I see lots of fab going on in the back ground . Can you get us up to speed on what you are up to 👍. All the best Danny UK 🇬🇧
@oldschool1993Ай бұрын
I found in road racing that a little toe in on full bump keeps the car tracking straight when braking hard for a corner. Once you get back hard on the throttle and the inner wheel goes into droop it will toe out and give you ackerman and help the car turn. The stiffness of your sway bar will determine how much.
@scottr9900Ай бұрын
Ackerman!!! Angelo did a pretty good explainer during his drift Cuda build. But of course, he used a Mustang II rack and a custom Flaming River rack.
@autoxcuda28 күн бұрын
With a Longacre gauge, I measured 0.082" toe out with 3" in bump/compression from static ride height in my particular 68 A-body w/'73 spool K-frame. Then, 0.114" toe-in with 3" jounce/extension from static ride height. I needed to take out shims to improve, but it already had no shims. So I'm sorta stuck, unless I start bending and welding stuff. Just my car, most every setup is different.
@junkerup28 күн бұрын
That’s not bad, but yeah every car is different due to aftermarket world these days
@autoxcuda28 күн бұрын
@@junkerup Is 3" up and 3" down from static overkill on range? Some other range more practical? My measurements are with a Heim tie rod setup. *Also check out my post on your other LBJ extension video for fitment applications.
@andyguffin401Ай бұрын
Thanks for putting out these videos and helping the average joe get the most out of their Mopar. What alignment specs do you shoot for when setting up for street/autocross?
@sandboxcowboy26 күн бұрын
Love the content! Trying to get my 68 dart w/ smallblock to handle tighter on street and future autox events. Drop balljoint brackets and tweaking the TRE angles like you have plus adjustable UCA should get me decent area? 🤔
@hazysativa3045Ай бұрын
Preach it...
@marcuscrammer4317Ай бұрын
Chris, this was very entertaining lesson I must say. Will you show the tweaking of the pitman in an upcoming video?
@dh2360Ай бұрын
There is a popular idea of using a 1973 and newer disc brake spindle for an easy disc brake conversion on 1972 and older B-bodies. The only thing is the 1973 and newer spindle is about 3/8 inch to 1 inch taller than the 1972 and older spindle, would this mean in increase in bump steer for a street driver? It would be convenient to use disc brakes off of FMJR bodies on older B-bodies but not if driveability becomes noticeably worst.
@autoxcuda28 күн бұрын
It's not 3/8" to 1" taller. It's about 3/8". It doesn't change. It's not that drastic.
@jeanettakelly5596Ай бұрын
Need to fire your dry waller Darin garle darn it😊
@jasonbirch1182Ай бұрын
Not trying to argue, just clarify I guess. How do you figure toe out under compression causes oversteer and toe in causes understeer? I can see the toe in I guess, by adding steering input while at the limit it's over using available grip, but I don't see any way the car towing out would cause oversteer. It reduces steering angle for sure but it's not affecting the rear. I have fully custom built control arms, roll center correction and steering angle/ratio increase I built on my Mercedes drift car so I'm pretty well versed in suspension geometry but always open and eager to learn more. I just made my first finals and lost(tires went away in the last round😔)against some catalog built drift cars in my one of one Mercedes, so I'm pretty proud of that. The car has been evolving for quite a few years as I learn and become more experienced fabricator and machinist as well as my drift experience growing.
@junkerupАй бұрын
It makes the car darty, which ever tire has the more load is going to dart that direction
@jasonbirch1182Ай бұрын
@@junkerup ok. That's not oversteer though. Really if the car is loose in the rear the toe in under compression will cause oversteer. Bump steer sucks all around! Nice to see someone who has a grasp on suspension geometry messing with junk that shouldn't do what it does. There's actually a couple guys that drift b-bodys near me. I'm not sure what they have done in the front though to be honest.
@trolllibtards2604Ай бұрын
👍🏻👍🏻
@TheProchargedmoparАй бұрын
👍💪 Excellent!!!
@TexHasselhoffАй бұрын
👍
@Kowalski401Ай бұрын
Great explanation! Which bump steer kit fits the mopar steering arm?
@danielnunez3518Ай бұрын
I wonder what led them to design such a wonky geometry. The 70s was more than 50 years ago but there were cars that handled decent
@bernierezny8156Ай бұрын
Will you do a rear setup to 👍
@cudak888Ай бұрын
Chris, do you have any experience with the B-body geometry when Mopar quick-ratio pitman and idler arms are installed? As I recall, the longer arms raise the drag link higher than the standard idlers, but I assume the extra length means the larger radius sweep as the arms spin may contribute to more aggressive droop from center to lock, and thus might benefit the geometry of the tie rod assembly only over a limited degree of steering input. I'm curious if you've had any experience with these that you may be able to share. For reference, I'm running FMJ spindles/knuckles, so while I am gaining a bit of height on the UCA (which are +1.5 FFI tubulars), I'm limited at what I can do with the steering arm height (obviously, I can't benefit from your kit as I'm not running drum spindles).
@junkerupАй бұрын
I do know the longer pitman and idler have better bumpsteer but I haven’t checked the Ackerman on that
@cudak88828 күн бұрын
@@junkerup Good to know. Thanks for being the absolute guru on this; trying to learn front end geometry _starting_ with a B-body is NOT a good idea without the right tutor, but your videos have been absolutely phenomenal. Thanks a million!
@user-bg2ed5yg8bАй бұрын
would like to see the chevelle run again
@junkerupАй бұрын
It did…not good
@shootysshiftboxesАй бұрын
Appreciate you De-BSing aftermarket parts for our mopars. In the Mopar Performance Oval track books I have it says to put shims inbetween the steering box in the K member to raise or lower the pitman arm to match the height of the idler arm
@sandboxcowboy26 күн бұрын
Thats interesting one 🤔
@anthonymanganaro994229 күн бұрын
What's up Chris! It's Anthony in Fort Lauderdale. Do you still have the 68 Charger?
@benshore7357Ай бұрын
Good times 🎉 not too sure about a butt welded tie rod but you said it was just for mock up. If you welded a sleeve over it might be legit?
@petecrabtree6734Ай бұрын
🦅🇺🇸💪😎👍
@allenpp674817 күн бұрын
Where did you buy those bumpsteer tire rods? I cant find them anywhere for a Mopar.
@user-se5oe6nh6vАй бұрын
Gregpolhnas
@bluesmoke218Ай бұрын
Got a bump steer gauge that you would recommend?
@joebutterfield4143Ай бұрын
Will your lowering brackets work on a 73 b_body
@junkerupАй бұрын
I don’t believe so
@K4TORG412Ай бұрын
if they only put the steering in front of the lower control arm at the same points. then this problem would not exist and the oil problem would be gone on top
@dusterowner9978Ай бұрын
UHHH ????
@junkerupАй бұрын
Uhhh what
@dusterowner9978Ай бұрын
@@junkerup my head hurts
@daryllynhutchins845928 күн бұрын
Thanks but boreing lve heard the word bump or bumpsteer enough for a while