What gears to run up to and over 200mph
03-23-2003, 07:10 PM
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Re: What gears to run up to and over 200mph </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Colonel:
<strong> BTW, you'd be turning only 4478 RPM in 6th gear at 200 MPH with the stock gears.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Actually, I read that Lingenfelter said our 6th gears would not be strong enough to support the necessary power to pull such high speeds even if one made the necessary power to do so.
The ratio in a 3.42 geared LS1 in 6th is a mere .5 to 1.
Compare that to the power gear ratio of 4th which is 1.00 to 1 . . . well everyone gets the idea <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
I'd estimate an LS1 dynoing something north of 600rwhp would be needed to pull in 6th.
That's why I do all of my top-speed runs in 5th with a limiter of 7000 rpm's.
BTW: 6600 rpm's in 5th with 3.42 gears would be 199 mph, while 6700 would be 202 <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
The following were equations posted on another site </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 20 HAWK 02 :
<strong> GauSSian wrote:
"depending on conditions (as you know there are a lot of conditions) you will need anywhere from 400-470 rwhp to make 181 mph.
Using P = 0.5*A*CD*p*v^3
P = power
A = max. cross-sectional area ~=3.0 m^2
CD = 0.32
p = density of air = 1.29 kg/m^3
v = velocity = 181 mph = 80.91 m/s
Get someone with a radar gun to verify your speed.
This calculation is based upon ideal conditions and does not even consider such things as lift and handling and body integrity. depending on conditions (as you know there are a lot of conditions) you will need anywhere from 400-470 rwhp to make 181 mph. "
That is the correct equation to determine power, however, how did you come by an Area of 3.0 m^2? This should be the frontal area of the car, or the width x height. I just made a rough measurement and got 25.5 sq ft, or 2.37 m^2. Using this value, and a CD of 0.35 (lights up?) , density = 1.225 kg/m^3 (value at STP) and a velocity of 185 mph (82.7 m/s), I calculated required power at the wheels to be 385 hp. Of course, like you said conditions can vary. Also, the rolling friction of the rear wheels should already be figured into any chassis dyno measurement, but not the front wheels. Still, I think 400 rwhp should come very close to, if not acheiving 185 mph under the right conditions. . . . </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The above might seem confusing but it was posted because I've gone just above 6100 rpm's in 5th which I estimated to be ~185 mph. 6100 is 184 and 6200 is 187.
<small>[ March 23, 2003, 10:59 PM: Message edited by: The Dragon ]</small>
<strong> BTW, you'd be turning only 4478 RPM in 6th gear at 200 MPH with the stock gears.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Actually, I read that Lingenfelter said our 6th gears would not be strong enough to support the necessary power to pull such high speeds even if one made the necessary power to do so.
The ratio in a 3.42 geared LS1 in 6th is a mere .5 to 1.
Compare that to the power gear ratio of 4th which is 1.00 to 1 . . . well everyone gets the idea <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
I'd estimate an LS1 dynoing something north of 600rwhp would be needed to pull in 6th.
That's why I do all of my top-speed runs in 5th with a limiter of 7000 rpm's.
BTW: 6600 rpm's in 5th with 3.42 gears would be 199 mph, while 6700 would be 202 <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
The following were equations posted on another site </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 20 HAWK 02 :
<strong> GauSSian wrote:
"depending on conditions (as you know there are a lot of conditions) you will need anywhere from 400-470 rwhp to make 181 mph.
Using P = 0.5*A*CD*p*v^3
P = power
A = max. cross-sectional area ~=3.0 m^2
CD = 0.32
p = density of air = 1.29 kg/m^3
v = velocity = 181 mph = 80.91 m/s
Get someone with a radar gun to verify your speed.
This calculation is based upon ideal conditions and does not even consider such things as lift and handling and body integrity. depending on conditions (as you know there are a lot of conditions) you will need anywhere from 400-470 rwhp to make 181 mph. "
That is the correct equation to determine power, however, how did you come by an Area of 3.0 m^2? This should be the frontal area of the car, or the width x height. I just made a rough measurement and got 25.5 sq ft, or 2.37 m^2. Using this value, and a CD of 0.35 (lights up?) , density = 1.225 kg/m^3 (value at STP) and a velocity of 185 mph (82.7 m/s), I calculated required power at the wheels to be 385 hp. Of course, like you said conditions can vary. Also, the rolling friction of the rear wheels should already be figured into any chassis dyno measurement, but not the front wheels. Still, I think 400 rwhp should come very close to, if not acheiving 185 mph under the right conditions. . . . </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The above might seem confusing but it was posted because I've gone just above 6100 rpm's in 5th which I estimated to be ~185 mph. 6100 is 184 and 6200 is 187.
<small>[ March 23, 2003, 10:59 PM: Message edited by: The Dragon ]</small>
03-23-2003, 07:19 PM
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Re: What gears to run up to and over 200mph </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by PacerX:
<strong> If you really want to run 200mph, do yourself a favor and pull the outside rearview mirror assemblies, switch to skinny tires and lower the car.
You'll get more benefit from those than a considerable amount of horsepower. Wind resistance is enemy #1 at 200mph. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Actually, suspension should be addressed first.
This is from real-world testing.
My friend's '02 WS6 car (IMTHECEO on the other site) is ~1 inch lower than my Firehawk. He does not have an aftermarket suspension. Although he does have springs obviously.
His car is far more unstable at speeds above 150 mph when compared to mine.
Everyone remember, distance from the ground is very important when one considers traveling at lift speeds.
BUT if you do not have a suspension to keep you glued to the ground, ANY bump or rise in the road will create an area under the car sufficient enough to LIFT the car . . . this was unfortunately tested by a friend of mine <img border="0" title="" alt="[Embarrassed]" src="gr_emb.gif" /> <img border="0" title="" alt="[Frown]" src="gr_sad.gif" /> (also, it takes a heck of a lot more time to accelerate 50 mph more when starting at 150 rather than 0 mph)
Do suspension first (this includes lowering), power next: somewhere between 390 and 440 rwhp on an F-body . . . this will vary depending on make of car and time of day, then down-force is needed.
<small>[ March 23, 2003, 11:03 PM: Message edited by: The Dragon ]</small>
<strong> If you really want to run 200mph, do yourself a favor and pull the outside rearview mirror assemblies, switch to skinny tires and lower the car.
You'll get more benefit from those than a considerable amount of horsepower. Wind resistance is enemy #1 at 200mph. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Actually, suspension should be addressed first.
This is from real-world testing.
My friend's '02 WS6 car (IMTHECEO on the other site) is ~1 inch lower than my Firehawk. He does not have an aftermarket suspension. Although he does have springs obviously.
His car is far more unstable at speeds above 150 mph when compared to mine.
Everyone remember, distance from the ground is very important when one considers traveling at lift speeds.
BUT if you do not have a suspension to keep you glued to the ground, ANY bump or rise in the road will create an area under the car sufficient enough to LIFT the car . . . this was unfortunately tested by a friend of mine <img border="0" title="" alt="[Embarrassed]" src="gr_emb.gif" /> <img border="0" title="" alt="[Frown]" src="gr_sad.gif" /> (also, it takes a heck of a lot more time to accelerate 50 mph more when starting at 150 rather than 0 mph)
Do suspension first (this includes lowering), power next: somewhere between 390 and 440 rwhp on an F-body . . . this will vary depending on make of car and time of day, then down-force is needed.
<small>[ March 23, 2003, 11:03 PM: Message edited by: The Dragon ]</small>
03-23-2003, 07:34 PM
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Re: What gears to run up to and over 200mph </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by JimMueller:
<strong> </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Pro Stock John:
I think my Formula once it makes 700rwhp may have to try a top speed run I bet I can hit 220mph but I don't know if I can afford the tires. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> ]</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">. . . I've heard that it's wiser to not worry so much about the vacuum created by lowering the car as much as it is creating downforce. You'll always have the downforce at speed...but what happens if you hit a decent bump which upsets the vacuum under the car? I'll take the downforce. . .
</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">What's up Jim! Long time no e-mail <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
I am in 100% agreement with Jim <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> Downforce is key to surviving this feat.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Quickin:
<strong> Can I make 200. I'm lowered about 1.5" all around.
I think my rev-limiter is set at 6,500.
Assume 510 RWHP.
Just curious.
</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Basically, assuming your 6th is .5 to 1, no.
With your 3.73's and assuming your tire size is somewhere around 25.66 you can only go 180mph at 6500 rpm's in 5th. 6400 would be 177. I don't think you have enough power to pull 6th to that speed.
I still wanna ride in your car <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
<small>[ March 23, 2003, 11:11 PM: Message edited by: The Dragon ]</small>
<strong> </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Pro Stock John:
I think my Formula once it makes 700rwhp may have to try a top speed run I bet I can hit 220mph but I don't know if I can afford the tires. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> ]</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">. . . I've heard that it's wiser to not worry so much about the vacuum created by lowering the car as much as it is creating downforce. You'll always have the downforce at speed...but what happens if you hit a decent bump which upsets the vacuum under the car? I'll take the downforce. . .
</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">What's up Jim! Long time no e-mail <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
I am in 100% agreement with Jim <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> Downforce is key to surviving this feat.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Quickin:
<strong> Can I make 200. I'm lowered about 1.5" all around.
I think my rev-limiter is set at 6,500.
Assume 510 RWHP.
Just curious.
</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Basically, assuming your 6th is .5 to 1, no.
With your 3.73's and assuming your tire size is somewhere around 25.66 you can only go 180mph at 6500 rpm's in 5th. 6400 would be 177. I don't think you have enough power to pull 6th to that speed.
I still wanna ride in your car <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
<small>[ March 23, 2003, 11:11 PM: Message edited by: The Dragon ]</small>
03-23-2003, 08:05 PM
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Re: What gears to run up to and over 200mph </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by v7guy:
<strong> . . . I was also informed that a rear diffuser is necessary at 180+ I believe it was.
. . . also a front air damn is needed to keep air from going under the car, and side skirts are nice, all this stuff should be temporary and something that can be removed when done with the run . . . </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">This is why I ordered my front air dam last week and it's going on tomorrow <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
It's gonna stay on too <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
I'm concerned about the rear difuser though . . .
I have gone 180+ without one <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
After the Airdam install we're gonna tape my top-speed run (I run high speeds eg. 170+ mph every weekend but have never stayed in it longer than ~6170ish rpm's in 5th). . . I've never gone above 6200 in 5th . . . but this weekend I'm gonna attempt 6500 which would be 196.
My only decision is whether or not to risk a night run . . . I'm worried about the headlights rippin' off at that speed <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
<small>[ March 23, 2003, 08:18 PM: Message edited by: The Dragon ]</small>
<strong> . . . I was also informed that a rear diffuser is necessary at 180+ I believe it was.
. . . also a front air damn is needed to keep air from going under the car, and side skirts are nice, all this stuff should be temporary and something that can be removed when done with the run . . . </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">This is why I ordered my front air dam last week and it's going on tomorrow <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
It's gonna stay on too <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
I'm concerned about the rear difuser though . . .
I have gone 180+ without one <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
After the Airdam install we're gonna tape my top-speed run (I run high speeds eg. 170+ mph every weekend but have never stayed in it longer than ~6170ish rpm's in 5th). . . I've never gone above 6200 in 5th . . . but this weekend I'm gonna attempt 6500 which would be 196.
My only decision is whether or not to risk a night run . . . I'm worried about the headlights rippin' off at that speed <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
<small>[ March 23, 2003, 08:18 PM: Message edited by: The Dragon ]</small>
03-23-2003, 08:16 PM
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Re: What gears to run up to and over 200mph </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 1BadAzzBlkWs6:
<strong> . . . in a Z06 . . . 200 will be alot easier . . . </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I'd like to know if this statement is really true. 200 being a lot easier with a ZO6 I mean.
Everyone always talks about the instability of the ZO6 at high speeds (again, the key word being high eg. 180+mph). . . no wing or ground effects/dams for down-force etc.
Weight of said vehicles would be negligible since at lift speeds weight becomes less and less a factor.
<strong> . . . in a Z06 . . . 200 will be alot easier . . . </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I'd like to know if this statement is really true. 200 being a lot easier with a ZO6 I mean.
Everyone always talks about the instability of the ZO6 at high speeds (again, the key word being high eg. 180+mph). . . no wing or ground effects/dams for down-force etc.
Weight of said vehicles would be negligible since at lift speeds weight becomes less and less a factor.
03-23-2003, 08:21 PM
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Re: What gears to run up to and over 200mph http://www.f-body.org/gears/
Here's a link to a tire/gear-ratio calculator for anyone curious.
Just an FYI fellas, these speeds are no joking matter. A buddy of mine nearly killed himself just last week on one of our routine runs (he was somehwere north of 175 mph when he hit a small, that is s m a l l, bump and his rear went AIR BORN <img border="0" title="" alt="[Frown]" src="gr_sad.gif" /> ).
I try to do as many mechanical and diagnostic checks as possible to my car every weekend before these forrays into insanity: eg. lugs torqued and checked for anomalies, tire tread and pressure checked to exact numbers, under carriage checked for anything loose or hanging, exhaust hangers checked, any debris in the filter or under carriage, all screws leading from the lid to and including the throttle-body tightened, head light assembly screws and brackets checked, various auto taps on different parameters of the vehicle, any codes that might have been thrown . . . you get the picture. Also, these runs are done on an exclusive stretch of highway with little to no traffic (I make certain none of my runs are done with any cars on that stretch where I drop the hammer).
As it is, just Friday night while racing four sport bikes (one being a GSXR 1000) my lid popped loose, blew my engine sensor fuse, and my serpentine belt was almost completely off <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
Our cars weren't meant to handle this kind of abuse . . . in the same token neither were they meant to be run at the track every weekend <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
This is what I, and a very few others, like to do.
If you ever attempt this, try and be as safe as possible.
<img border="0" alt="[USA]" title="" src="graemlins/patriot.gif" />
<small>[ March 23, 2003, 08:50 PM: Message edited by: The Dragon ]</small>
Here's a link to a tire/gear-ratio calculator for anyone curious.
Just an FYI fellas, these speeds are no joking matter. A buddy of mine nearly killed himself just last week on one of our routine runs (he was somehwere north of 175 mph when he hit a small, that is s m a l l, bump and his rear went AIR BORN <img border="0" title="" alt="[Frown]" src="gr_sad.gif" /> ).
I try to do as many mechanical and diagnostic checks as possible to my car every weekend before these forrays into insanity: eg. lugs torqued and checked for anomalies, tire tread and pressure checked to exact numbers, under carriage checked for anything loose or hanging, exhaust hangers checked, any debris in the filter or under carriage, all screws leading from the lid to and including the throttle-body tightened, head light assembly screws and brackets checked, various auto taps on different parameters of the vehicle, any codes that might have been thrown . . . you get the picture. Also, these runs are done on an exclusive stretch of highway with little to no traffic (I make certain none of my runs are done with any cars on that stretch where I drop the hammer).
As it is, just Friday night while racing four sport bikes (one being a GSXR 1000) my lid popped loose, blew my engine sensor fuse, and my serpentine belt was almost completely off <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
Our cars weren't meant to handle this kind of abuse . . . in the same token neither were they meant to be run at the track every weekend <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
This is what I, and a very few others, like to do.
If you ever attempt this, try and be as safe as possible.
<img border="0" alt="[USA]" title="" src="graemlins/patriot.gif" />
<small>[ March 23, 2003, 08:50 PM: Message edited by: The Dragon ]</small>
03-25-2003, 05:14 AM
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Re: What gears to run up to and over 200mph </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by The Dragon:
<strong> This is what I, and a very few others, like to do.
If you ever attempt this, try and be as safe as possible.
<img border="0" alt="[USA]" title="" src="graemlins/patriot.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Hey bro, i'll finally be joining in on this insanity this weekend!!! But I don't think i'm gonna take it to 200!!! <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> Don't exactly know how stable my Z is gonna be at top speeds, so i'll go till it's starts to get unstable and then let off, just to see the limits of it!! <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
<small>[ March 25, 2003, 05:16 AM: Message edited by: Loudmouth LS1 ]</small>
<strong> This is what I, and a very few others, like to do.
If you ever attempt this, try and be as safe as possible.
<img border="0" alt="[USA]" title="" src="graemlins/patriot.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Hey bro, i'll finally be joining in on this insanity this weekend!!! But I don't think i'm gonna take it to 200!!! <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> Don't exactly know how stable my Z is gonna be at top speeds, so i'll go till it's starts to get unstable and then let off, just to see the limits of it!! <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
<small>[ March 25, 2003, 05:16 AM: Message edited by: Loudmouth LS1 ]</small>
03-25-2003, 07:25 AM
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Re: What gears to run up to and over 200mph I don't care what my tach said because our tachs are off anyhow; therefore, how fast would you say I was going when my SS banged the rev-limiter(set at 6800 by Pro Auto Tech) in 5th gear, considering drag coefficient, and rolling resistance? I would guess at least 170-175mph. My speedo was pegged way before I hit rev-limiter. <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />
this was with about 380RWHP and stock 10 bolt with 3.42s
this was with about 380RWHP and stock 10 bolt with 3.42s
03-25-2003, 09:09 AM
#49
Re: What gears to run up to and over 200mph You dont want to be in 6th, or 5th for that matter. I believe the Callaway "SledgeHammer" had gears taller than a 3.00:1, and was in 4th
Going into Overdrive eats HP. you want to be at your target speed, at your target RPM, in a gear that is 1:1. Nascar- TALL, gears, 190+ in 4th <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
If shifting to 5th was better, drag racers would put 5.88 gears in their car, and shift to 5th.
Aero was mentioned, and needs to be mentioned again. A car is like a large wing, and will actually start to create lift at higher speeds ( This is why they feel like they "float"- they really are)
In the Trans Am cars at tracks like Daytona, Road America, Mosport, ect. We run 5th gear as 1:1 ( Hewland box) Never, ever OD. Rear gears range from 3.89s- 3.33s ( Keep in mind, RPMs are in the range of 7800-8200 with a 28" tall tire)
Just some things to chew on <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Louis
Going into Overdrive eats HP. you want to be at your target speed, at your target RPM, in a gear that is 1:1. Nascar- TALL, gears, 190+ in 4th <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
If shifting to 5th was better, drag racers would put 5.88 gears in their car, and shift to 5th.
Aero was mentioned, and needs to be mentioned again. A car is like a large wing, and will actually start to create lift at higher speeds ( This is why they feel like they "float"- they really are)
In the Trans Am cars at tracks like Daytona, Road America, Mosport, ect. We run 5th gear as 1:1 ( Hewland box) Never, ever OD. Rear gears range from 3.89s- 3.33s ( Keep in mind, RPMs are in the range of 7800-8200 with a 28" tall tire)
Just some things to chew on <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Louis
03-25-2003, 05:21 PM
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Re: What gears to run up to and over 200mph </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by G2 LS1:
<strong> You dont want to be in 6th, or 5th for that matter. . .
Going into Overdrive eats HP. you want to be, in a gear 1:1.
Aero was mentioned, and needs to be mentioned again. A car is like a large wing, and will actually start to create lift at higher speeds . . .
Just some things to chew on <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Louis </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Absolutely agree <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
I'm forced to go into 5th because my 4th tops out at a mere 152 <img border="0" title="" alt="[Frown]" src="gr_sad.gif" />
5th is .74:1 . . . not great but better than nothing <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
Devon: get some flow or we'll work something else out and you can join in this weekend. I'll just reset you top speed to 165. I don't trust the aero of your car lacking a wing and front air dam plus you need a suspension as well <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
<strong> You dont want to be in 6th, or 5th for that matter. . .
Going into Overdrive eats HP. you want to be, in a gear 1:1.
Aero was mentioned, and needs to be mentioned again. A car is like a large wing, and will actually start to create lift at higher speeds . . .
Just some things to chew on <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Louis </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Absolutely agree <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
I'm forced to go into 5th because my 4th tops out at a mere 152 <img border="0" title="" alt="[Frown]" src="gr_sad.gif" />
5th is .74:1 . . . not great but better than nothing <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
Devon: get some flow or we'll work something else out and you can join in this weekend. I'll just reset you top speed to 165. I don't trust the aero of your car lacking a wing and front air dam plus you need a suspension as well <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
03-25-2003, 07:47 PM
#51
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Re: What gears to run up to and over 200mph The average speed record for the Silver State Classic is 208 mph and is held by a Chrysler LeBaron. The most recent winner was a 1996 Camaro at 197 MPH. The SSC is a 90 mile race on a public highway in Nevada.
03-25-2003, 10:59 PM
#52
Re: What gears to run up to and over 200mph Some of you may have noticed, but the Z06 was designed for the race track in mind when they built the gearbox. The 5th in those cars is not much of a 5th. The 4/5 split is very small. ~ 1000 rpms. 5th gear also has no rev limiter for you LS1edit guys.
04-06-2008, 10:16 PM
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I went 7000rpm in 5th gear with stock gears. Did not have a gps to see how fast I was going. Car felt good, it is lowered and handled alright. It has 420rwhp.
04-06-2008, 11:42 PM
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I was guessing 5 miles, its probably more. I didn't go out and measure, I just know that I was racing the guy on the R1 Yamaha. I wanted to see how fast bikes were. We got to the beginning of the straight-away and then I did a second gear roll to top-end. He was about 5-6 seconds ahead of me when I reached top-end. Then I slowed to about 150 because he was slowing to get beside me and he slowed too much then we went again and he stayed beside me to see what I was doing. I don't know how I did 174 either with the limiter but thats what he read on the speedo. I don't have to lie. And it didn't take my car that long to reach top-end with all the hood mods I've done with my WS6 and all the additional mods I have in my Sig.
