You need more practice :lol:
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Thanks for the update, all interesting info. :nod:
Sucks you didn't go faster though, :(
That "tire shake" does sound like Reaper could have a point about the springs being under-damped though.... but could also be a little too much toe out under power.
do the cut out and the dropped logging coincide?
is the front rebound dampening on full stiff?
you gonna do a DJ semi-crash box mod while the trans is out?
im wondering if just doubling the springs like he did would help synchro engagement on an otherwise stock trans.
Brian
there you go. :)
Brian
I don't personally see damping as being a problem that would cause tire shake. Damping is velocity dependent so the quicker the spring wants to move the more the damping effects it. For myself I was seeing tire shake starting near the middle to the top of 2nd. For any given gear the only spot damping really comes into play is on the shift into the gear in rebound and the shift to the next gear in jounce. Once in the gear you are more or less into steady acceleration and the suspension travel has hit it's steady state position, therefore damping has no role. Tire shake to me is the resonance of the tire itself acting like a spring. When on the verge of traction the tire will slip and relax allowing it to grip again and then it is pushed to slip and back and forth. If you have more power it will just spin and less power and it will just hook. It's the nasty in between where you get the shake.
It would for sure help a stock trans as it helps the shafts match speeds. Unfortunately I'm not a fan of pulling or rebuilding trannys so I did everything at once and didn't get to see what the individual changes would do. :thumb:
I can see your point there about the damping, yes tire shake may happen still if all else is "perfect", but it may happen sooner than it should if something is underdamped (spring hits a harmonic and keeps kicking tire out of traction) or overdamped (suspension is far too rigid and minor undulations in surface keep throwing tire out of traction) rather than being at the absolute traction limit for that tire..... could also be due to any slight slop in suspension components.
Just to clarify, I was only going after the launch of the car and the energy transfer that is related to that action, not the tire shake.
For the tire shake, did you try different pressures in the tires? That would change the resonance frequency. :thumb:
Good point...
I guess you could whack your tire and whack your coil spring and if they make close to the same note, then rig it so they don't.
Inertia... or more importantly momentum. Making things stiff and damped seems to have reduced the mometum of the chassis moving around. I tried 1 turn (40%) and 2 turns (80%) should have tried 0. Similar lauches (60') with each setting, more tire shake with 80% ... Hmmm...
ALWAYS! :thumb:
toe is almost 0°... a couple minutes negative at rest and 0° on lift, so it should never toe out. Does anyoen have the factory alignment specs handy?
Cut out and drop in logging are seperate issues.
No, ~40% and ~80% as noted above...
Would love to, but not sur eif I go ttime... DJ, you think a bench grinder can remove dog teeth OK? ;)
Definitely planning to double up slider springs.
I actually have access to a "calibrated hammer" (insert Ford tool # 001 joke here) but I am not sure if you could ever get a rubber tire and steel spring to make a similar note?
I am trying to decide if I want to go stiffer spring in the rear... Hmmm...
JT, are those your PB for 60'? Glad it's working for you!
Thanks. Those were not tho... it has cut 1.67 60' Recently no better than 1.8 so the 1.7's are moving back in the correct direction :thumb:
Almost exactly 2 years. I was thinking that too... and thinking 26's.
Funny thing, these tires have looked pretty ratty since spinning 1/8 mile at Mason-Dixon, but after this past event they are actually looking much better with more even wear.
Really? I cannot see a "thud" sounding like a "tink"
Install travel limiters on the front?
Just weld angle iron to each coil on the front springs.
Sent from my DROID X2 using Tapatalk
I microphone and a computer can record the sound. Then you can analyze the frequency the sound made. Once you do that, then you can see if they are close to the same harmonic. It doesn't matter if they are the same frequency.