#93, "Put 14s back on for winter. My god what a power mod!"
LAST EDITED ON 04-Dec-00 AT 07:54 AM (PST)
185/70/14s no less. These are going to last 2wks at the current rate I'm lighting em up. I mean I'm lighting em up all the way through 8 lane intersections (for no other reason than its so effortless). Now I can finally feel my mods. I didn't have monster wheels to begin with (17" @23lbs each). Hell I damn near tempted to keep it this way.. FOREVER (nah).
#94, "RE: Put 14s back on for winter. My god what a power mod!" In response to Reply # 0
Do you think you would see a difference at the track with those tires over your 17's. I am thinking about trading my stock 16" GS wheels for a set of the RS rims and tires. I run 17's as well, but am thinking about running the 14's at the track next summer. Since I started modding my car (performance wise), I have had those 17's on my car. You think I would notice a big difference putting those 14's on?
#95, "RE: Put 14s back on for winter. My god what a power mod!" In response to Reply # 1
I think a lot of people run the smaller rims at the track for faster times. I would bet you would see a difference in your times. I would like to see what the difference is. Anybody go to the track and run a couple with 17" and then swap for the 14". What was the difference???
Firefly: Mal: You don't know me, son, so let me put this to you plainly: If I ever kill you, you'll be awake. You'll be facing me. And you'll be armed.
#96, "RE: Put 14s back on for winter. My god what a power mod!" In response to Reply # 2
I know Todd VX100 (or something like that) has run with 14" and 16" tires. He said he was having trouble breaking back into the 15s (from low 16s) until he put the stock 14s back on. I'm pretty sure you'll be able to launch better with the 14s if nothing else. When it gets warm again the first thing I'm doing is getting a set of 14" drag radials or slicks. If I could turn that wheel spin into foward motion who knows what it would do.
#97, "you bet the stock setup helped!" In response to Reply # 3
You're right Stan. I had run a fastest time of about 16.1 with 16 by 8 inch rims, mazda RX-7 rims to be exact, which are very light, and 225/50 tires which also wern't all that heavy. When I put the stock rims/tires back on I hit 15.8. It was a bit colder that night too, so I'd think the difference was at least 2/10ths of a second.
I noticed the power difference as soon as I put on the stock tires again,the car felt noticeably faster, and going to the drag strip proved it.
If you're going to drag race, stick with the stock RS rims and tires, I would say you can't beat them.
I'm still keeping the other setup for autocross, the handling is great with those rims and tires!
stan do you know the weight of the stock 14's or the stock alloys? im curious about my wheels hindering my performance. my 19's weigh 25.3 lbs according to konig, and thats chrome. i dont know how they pulled off only 25 lbs on a chrome 19". i dont know what my 18s weighed but i couldnt tell a difference. then again i was on stock alloys, not steeleys. someone post the weights if they know them please, it would be helpful
I dont know the weight of either but I do know larger diameter tires also weigh more than smaller tires and thats often overlooked. So even if your 19's weighed 25lbs. The tires will likely be heavier than anything smaller. I can see how they pulled off 25lb 19's. Thats as easy as the process used to make them. What I don't know is how they pulled it off so cheaply (they aren't very expensive for there size, weight and looks).
yeah that was why i was wondering how they did it because the tantrum is a one piece wheel, not designed to be lightweight. but i dont understand how a smaller higher profile tire with more rubber would weigh more than a 225/35/19 with only an inch and a half of sidewall...one of lifes little mysteries i guess.
Even if the wheels weighed the same. the 14" wheel would spin more easily than a 17" or 18". The distibution of mass is different. Because in the 14" wheel the weigh actually has a shorter path to complete around the axis of rotation. It's like an ice skater they spin the fastest when their arms and legs are tight against their body and and to slow themselves down they put their arms and leg out. So for a rotating mass the smaller the better. Hell find 13" rim for the track, and you'll have another gain. Sorry if this explanation didn't make sense I haven't had to do physics in a couple years now. If something doesn't make sense let me know I'll try to elaborate
Firefly: Mal: You don't know me, son, so let me put this to you plainly: If I ever kill you, you'll be awake. You'll be facing me. And you'll be armed.
#102, "excellent point Mike!" In response to Reply # 8
>Even if the wheels weighed the >same. the 14" wheel would >spin more easily than a >17" or 18". The distibution >of mass is different. Because >in the 14" wheel the >weigh actually has a shorter >path to complete around the >axis of rotation. It's like >an ice skater they spin >the fastest when their arms >and legs are tight against >their body and and to >slow themselves down they put >their arms and leg out. >So for a rotating mass >the smaller the better. Hell >find 13" rim for the >track, and you'll have another >gain. >Sorry if this explanation didn't make >sense I haven't had to >do physics in a couple >years now. If something doesn't >make sense let me know >I'll try to elaborate
You got it right Mike, that's a good explanation.
Going along those same lines, the mass at the VERY OUTER EDGE of the tire is what should affect the rotational inertia the most. The tire's tread is further out than the rim of the wheel, right? So the tire should affect the rotational inertia more than the rim. The larger rim should also have an affect, but I'm guessing the wider tire is causing most of the "power loss."
My tires were 225s, compared to 195s that's 15% more tread (and at least 15% more weight) at the very outer diameter of the tire, now multiply that by 4 tires and I guess it was enough to cost me that 2/10ths at the drag strip.
So, a heavier rim might not make all that much of a difference, a heavier/wider tire would. Of course lighter is always better, since you also have to accelerate that mass in a straight line, and it adds to suspension unsprung weight.
So as crazy as it sounds you might see a small negative difference with a 195 tire on a 18 inch rim (bear with me here, I know no one would do this) and a huge negative difference with a 225 tire on a 14 inch rim (if the outer diameter is the same)
#103, "RE: excellent point Mike!" In response to Reply # 9
With regards to your extra wieght of the tire very good point also, I wasnt really concidering the tire weight. Does any one know the differences in weight of stock tires vs. 225s?
I think the differences in tire weight are going to be much less than that of wheel weight, rubber has a lighter weigh pet volume than metal. Given a wheel weights 25lbs say I can't imagine that a tire weighs more than say 10lbs at most. If I'm wrong on this someone please correct me. In which case the tire will have more of an effect than I thought. And I think you only need to multiply the extra weight by 2 since its a FWD car and not an AWD car. We can concentrate on the wheels that the engine is directly turning. I think we can look at the extra friction and drag the rear tires create by being wider. This is the reason drag racing cars have bicycle tires up front. But I think you're right we need to look at the outer edge weight.
Let's concider the weight distribution: Assuming same width tires say 225s one on 14" wheels one on 18: wheels. on the 14" the concentration of mass is closer to the center allowing the wheel to spin more easily. On the 18" wheels the tire and weigh of the rim are concetrated around the outer edge of the rotation mass. Which should make it harder to turn. I still think that the rim has a larger effect, based on what I think the weigh of the wheels vs. the tires is. If someone knows the weights of the tires alone I may change my thoery.
Also the smaller rim with larger tires is going to has it's mass closer to the center wich would in part offset the larger rotating mass of the wider tire. If this is done on a 18" rim you are only adding to the outer mass, or at the very least not taking much away from it. Let me know what you think.
Firefly: Mal: You don't know me, son, so let me put this to you plainly: If I ever kill you, you'll be awake. You'll be facing me. And you'll be armed.
