Conflicted help!
#1
Conflicted help!
15x8 6ul's or 15x8 tr motorsports and a gopro HD? I can only pick one. The 6ul is 12.4lbs and the tr's are 14.8lbs. I've wanted 6ul's since 2007 they are the boss wheel for the miata, but the tr's and the new gopro HD are pimp too. Either way I go these are for the track car. Help me decide....dammit this sucks.
#6
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Think about how you would actually use the video footage, and maybe that will help you decide. I have an Aiptek HD camera and built some better external mics for it because I thought it would be dope to put all kinds of track **** on youtube. It turns out that I usually end up burning the footage to DVD, and maybe watching it once or twice again for review, but mostly the DVDs sit collecting dust. Maybe I should upload some of those vids of my stock Miata embarrassing no-talent drivers in expensive cars, but I guess I'm just lazy. After a track weekend, messing with video just seems boring, unless it's something really fantastic that MUST be shared with the world. Of course, race footage would be generally more exciting than the HPDEs I do now.
As for the wheels, I lean towards getting the best parts that fit in my budget to make a track car faster. An extra 2.5 lbs of unsprung rotating mass per corner is not going to help you go faster. Looks are subjective, but every time I look at my car I think "My wheels are the **** and if I was still single I'd be getting tons of bitches." I also lean towards buying expensive stuff when you can afford it, and saving up and getting the cheaper stuff later, especially with electronics. You've wanted 6ULs for two years. In 2011, 6ULs will still be awesome and there will be some new whiz-bang video camera on the market.
As for the wheels, I lean towards getting the best parts that fit in my budget to make a track car faster. An extra 2.5 lbs of unsprung rotating mass per corner is not going to help you go faster. Looks are subjective, but every time I look at my car I think "My wheels are the **** and if I was still single I'd be getting tons of bitches." I also lean towards buying expensive stuff when you can afford it, and saving up and getting the cheaper stuff later, especially with electronics. You've wanted 6ULs for two years. In 2011, 6ULs will still be awesome and there will be some new whiz-bang video camera on the market.
#12
Not to say "don't do it", but you would want to look into how that change in offset would change how the car handles under braking, how steering wheel angle changes camber, how steering wheel feel is affected...
Changing offset that wildly will change your suspension behavior. Good or bad? You decide.
Changing offset that wildly will change your suspension behavior. Good or bad? You decide.
#13
You really need to understand offsets to get this. A 9" rim is 228.6mm and a 8" rim is 203.2, now lets divide those numbers in half to get a 0 offset.
114.3 and 101.6
Now take a 9" 6UL that is a +36 offset. We add the +36mm to 114.3 to get 150.3 which is the distance from the rotor in. We then take that 114.3 and minus 36mm to get the rotor to outer wheel lip distance which is 78.3. Since we know that the 949 6UL is about as large as you can go on our car, well inboard that is, then we really want to stay smaller than the 150.3 inner and as close as you can or smaller than the 78.3 outer or risk a big fender pull. The 8" Tr has a inner mm of 121.6 and an outer of 81.6. So the TR has around 30mm of inner clearance compared to the 9" 6UL and the outer is only 3.3mm wider in track than the 9" 6UL. I doubt that 3.3mm will make my car unstable and launch me into a tire wall.
Jake
114.3 and 101.6
Now take a 9" 6UL that is a +36 offset. We add the +36mm to 114.3 to get 150.3 which is the distance from the rotor in. We then take that 114.3 and minus 36mm to get the rotor to outer wheel lip distance which is 78.3. Since we know that the 949 6UL is about as large as you can go on our car, well inboard that is, then we really want to stay smaller than the 150.3 inner and as close as you can or smaller than the 78.3 outer or risk a big fender pull. The 8" Tr has a inner mm of 121.6 and an outer of 81.6. So the TR has around 30mm of inner clearance compared to the 9" 6UL and the outer is only 3.3mm wider in track than the 9" 6UL. I doubt that 3.3mm will make my car unstable and launch me into a tire wall.
Jake
#14
I didn't say anything about clearances or launching you into a tire wall. I didn't even say not to do it. Spazzy and can't read... nice combination.
The track isn't even directly what affects the suspension components I mentioned earlier. It's another aspect you change by altering your offset. Scrub radius. You'd be changing your scrub radius to a positive, by quite a bit. That would increase steering wheel feedback, bump steer, may give you inconsistant camber gains as the steering wheel turns, would make the car less stable under braking... in race cars, positive scrub radius is usually seen as a positive, in street cars, negitive scrub radius is usually a positive (strong positive scrub radius is an effective anti-yaw under braking). Zero is seen as "perfection" by some, but it has merits and minuses of its own.
Understand, then attack.
The track isn't even directly what affects the suspension components I mentioned earlier. It's another aspect you change by altering your offset. Scrub radius. You'd be changing your scrub radius to a positive, by quite a bit. That would increase steering wheel feedback, bump steer, may give you inconsistant camber gains as the steering wheel turns, would make the car less stable under braking... in race cars, positive scrub radius is usually seen as a positive, in street cars, negitive scrub radius is usually a positive (strong positive scrub radius is an effective anti-yaw under braking). Zero is seen as "perfection" by some, but it has merits and minuses of its own.
Understand, then attack.
#15
I didn't say anything about clearances or launching you into a tire wall. I didn't even say not to do it. Spazzy and can't read... nice combination.
The track isn't even directly what affects the suspension components I mentioned earlier. It's another aspect you change by altering your offset. Scrub radius. You'd be changing your scrub radius to a positive, by quite a bit. That would increase steering wheel feedback, bump steer, may give you inconsistant camber gains as the steering wheel turns, would make the car less stable under braking... in race cars, positive scrub radius is usually seen as a positive, in street cars, negitive scrub radius is usually a positive (strong positive scrub radius is an effective anti-yaw under braking). Zero is seen as "perfection" by some, but it has merits and minuses of its own.
Understand, then attack.
The track isn't even directly what affects the suspension components I mentioned earlier. It's another aspect you change by altering your offset. Scrub radius. You'd be changing your scrub radius to a positive, by quite a bit. That would increase steering wheel feedback, bump steer, may give you inconsistant camber gains as the steering wheel turns, would make the car less stable under braking... in race cars, positive scrub radius is usually seen as a positive, in street cars, negitive scrub radius is usually a positive (strong positive scrub radius is an effective anti-yaw under braking). Zero is seen as "perfection" by some, but it has merits and minuses of its own.
Understand, then attack.
Really? Because I explained offset...
Don't get all butt hurt cuz I hitz you wid da nawlegdgz kid...word.
#16
This just doens't make sense... scrub radius tuning is a preference, not a good or bad thing. It's not "butt hurt" of me to say "it's your car, do which option you like better."
#17
Cliffnotes: Knowing where the wheels are (offset) is different than knowing how they affect your suspension and steering (scrub radius).
This just doens't make sense... scrub radius tuning is a preference, not a good or bad thing. It's not "butt hurt" of me to say "it's your car, do which option you like better."
This just doens't make sense... scrub radius tuning is a preference, not a good or bad thing. It's not "butt hurt" of me to say "it's your car, do which option you like better."
#18
Track Width vs. Everything else - Corner-Carvers Forums
Also, you can use this skidpad simulator to see how 3mm extra track can affect your cornering forces: (not much, but useful for anyone interested in putting flares on their car)
Page 29
#19
Nagase that link you posted sucked.
FYI
Pros
increased dynamic camber gain
slower instance of center migration
slower weight transfer
Could be pro or con depending:
effective spring rate softer (higher wheel rate)
Cons:
increase scrub radius
increase load on already over loaded front bearings
think increase caster jacking
Keeping the (static design) scrub radius a little bit positive is better than zero because it keeps the state the same as the tire squirms from normal road irregularities and minor steering corrections... you don't want the scrub radius constantly flopping from pos to neg as you drive, alternately loading the joints in different directions when you just want to go straight.
Anyways picked up some more noob parts today.
FYI
Pros
increased dynamic camber gain
slower instance of center migration
slower weight transfer
Could be pro or con depending:
effective spring rate softer (higher wheel rate)
Cons:
increase scrub radius
increase load on already over loaded front bearings
think increase caster jacking
Keeping the (static design) scrub radius a little bit positive is better than zero because it keeps the state the same as the tire squirms from normal road irregularities and minor steering corrections... you don't want the scrub radius constantly flopping from pos to neg as you drive, alternately loading the joints in different directions when you just want to go straight.
Anyways picked up some more noob parts today.
Last edited by jacob300zx; 12-06-2009 at 02:54 AM.
#20
Nagase that link you posted sucked.
FYI
Pros
increased dynamic camber gain
slower instance of center migration
slower weight transfer
Could be pro or con depending:
effective spring rate softer (higher wheel rate)
Cons:
increase scrub radius
increase load on already over loaded front bearings
think increase caster jacking
Keeping the (static design) scrub radius a little bit positive is better than zero because it keeps the state the same as the tire squirms from normal road irregularities and minor steering corrections... you don't want the scrub radius constantly flopping from pos to neg as you drive, alternately loading the joints in different directions when you just want to go straight.
Anyways picked up some more noob parts today.
FYI
Pros
increased dynamic camber gain
slower instance of center migration
slower weight transfer
Could be pro or con depending:
effective spring rate softer (higher wheel rate)
Cons:
increase scrub radius
increase load on already over loaded front bearings
think increase caster jacking
Keeping the (static design) scrub radius a little bit positive is better than zero because it keeps the state the same as the tire squirms from normal road irregularities and minor steering corrections... you don't want the scrub radius constantly flopping from pos to neg as you drive, alternately loading the joints in different directions when you just want to go straight.
Anyways picked up some more noob parts today.