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With an M6 trans you don't want to shift beyond 4th gear in the quarter mile. It has a 1 to 1 ratio or is considered direct drive. shifting into 5th gear will effectively kill your ET.
The trap is the finish line or a spot just ahead of them where the radar guns are that record mph.
E.T. = Elapsed Time
Craig
Semi Retired Street Racer
2012 Lava Red Mustang GT 5.0 MT82
GONE BUT NOT FORGOTEN
sigpic NBM `98 Formula M6 HdTp
1 of 1 Build Date 3/12/98
"Political correctness is a doctrine, fostered by a delusional, illogical, liberal minority, and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end."
"For you who believe all you read, I caution you - you are daily being brainwashed for profit by extremely effective psychology with very little regard to factual accuracy. In short, you're at the mercy of the world's greatest bullshit artists with the morals of a stray tomcat." - Smokey Yunick
I wouldn't spend a dime on that stupid 10 bolt if it was me let alone a grand.
But if your dead set on it go with a 4.11 gear. If you are "running out of gear" you will be trapping around 120 and would benefit from going up to a bigger tire anyways.
3.73s are stronger because they have 9 pinion teeth, vs the 4.10s that have 10 pinion teeth. More teeth= smaller teeth therefore weaker. That being said, anyone know the pinion and ring count on a 4.11 gear?
2011 Mustang GT
20" Satin Black AMRs with 305/35 & 275/35 MT Street Radials, Saleen Grille, CS Lower Valance, Roush Axleback, GT500 Spoiler, resonator delete
That being said, anyone know the pinion and ring count on a 4.11 gear?
yes i would like to know this too. i want something that will not bring my mpg down horribly, but i def want to add accelleration and have a solid/strong rearend! I want to have a cruisin car that can hold its own if needed !!
I'm on the 3.73 bandwagon. Like has been said they are stronger than 4.10s. Otherwise do 4.11s (not 4.10) if you arent doing any serious engine mods. I'd personally be afraid of running out of gear in the quarter mile with a 4.xx gear and a modded car... youll go through the gears pretty quick.
so basically, what your saying is that with a higher gear ratio i.e- 4.xx as opposed to a 3.42/3.73 my rpm's will be topped out before i hit the end of the track?
so essentially, i would be decreasing my top end speed and increasing my accelleration?
so essentially, i would be decreasing my top end speed and increasing my accelleration?
Yes, a numerically higher gear (called a "shorter" gear) will increase acceleration, and decrease top speed.
I can't remember what my dad's '66 LeMans ran gear-wise, specifically, but it was pretty short - He ran a 13.0 @ 90mph. That was back in '68, so I doubt he remembers.
Gone but not forgotten: 1986 Chevrolet Camaro IROC-Z
so basically, what your saying is that with a higher gear ratio i.e- 4.xx as opposed to a 3.42/3.73 my rpm's will be topped out before i hit the end of the track?
so essentially, i would be decreasing my top end speed and increasing my accelleration?
The RPM should not be topped out but it will be close.
The idea is to maximize the gearing for the powerband and with the LS1 M6 combo during a 1/4 mile run you spend most of your time in 2nd and 3rd above 4000 rpm. You actually have to pull for 4th gear less then 100 feet from the traps/finishline and then pass them while spinning around 5000 rpm. This is not optimal when you consider a stock LS1 makes peak HP around 54-5500 rpm. So you want to maximize 4th gear, 3.73's will help but 4.10's would be better.
The real issue with 4.10's is traction and when you add Drag Radial's your rear is effectively turned into a Grenade with the pin pulled out.
Craig
Semi Retired Street Racer
2012 Lava Red Mustang GT 5.0 MT82
GONE BUT NOT FORGOTEN
sigpic NBM `98 Formula M6 HdTp
1 of 1 Build Date 3/12/98
"Political correctness is a doctrine, fostered by a delusional, illogical, liberal minority, and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end."
"For you who believe all you read, I caution you - you are daily being brainwashed for profit by extremely effective psychology with very little regard to factual accuracy. In short, you're at the mercy of the world's greatest bullshit artists with the morals of a stray tomcat." - Smokey Yunick
so in reading all this, to net it out. if you stay stock 3.42 you would have best gas mileage, but be slower et in 1/4. Going to a 3.73 would give better acceleration, worse gas mileage., and then put you into needing better sticky tires. And going to 4.10 gears would be the better choice for 1/4 mile, need better tires, (racing slicks) and get shitty mileage. and not hold up as well because its a weaker gear. So the average guy with a DD that might go to the track every year or maybe every other year, it seems best choice would be 3.73 gear then your gas mileage isn't in the dumpster and you can still be faster off the line in a street race.
Now I am interested in really confusing the issue, why not leave rearend stock and simply change tire size if you want to race. Everything stated is based on stock 23.5 diameter tires, So if you put a larger tire ie drag slicks on for the track are you not doing same thing as changing rear gear ratio?
sigpic
1998 Trans Am Convertible A4 - WS6 hood, WS6 air lid, WS6 rims, drilled/slotted rotors.
so in reading all this, to net it out. if you stay stock 3.42 you would have best gas mileage, but be slower et in 1/4. Going to a 3.73 would give better acceleration, worse gas mileage., and then put you into needing better sticky tires. And going to 4.10 gears would be the better choice for 1/4 mile, need better tires, (racing slicks) and get shitty mileage. and not hold up as well because its a weaker gear. So the average guy with a DD that might go to the track every year or maybe every other year, it seems best choice would be 3.73 gear then your gas mileage isn't in the dumpster and you can still be faster off the line in a street race.
Now I am interested in really confusing the issue, why not leave rearend stock and simply change tire size if you want to race. Everything stated is based on stock 23.5 diameter tires, So if you put a larger tire ie drag slicks on for the track are you not doing same thing as changing rear gear ratio?
Stock tire diameter is approx 25.5".
Changing tire diameter will effect gearing and also speedometer calibration
But you would need a shorter tire to equal the effect of shorter gears like 3.73's.
A taller tire say around 27" would effectively give the car the feeling of having 3.23's.
And BTw the fuel mileage isn't as big an issue as one might think.
The effective rpm change from 3.42's to 4.10's at 70 mph in 6th gear is roughly 3-400 rpm.
Personally I wouldn't reccomend 4.10's in the stock rear.
Motive does make a 3.90 gearset for the 7.5" 10 bolt that would be more robust and offer a better trade off compared to the 3.73's.
Craig
Semi Retired Street Racer
2012 Lava Red Mustang GT 5.0 MT82
GONE BUT NOT FORGOTEN
sigpic NBM `98 Formula M6 HdTp
1 of 1 Build Date 3/12/98
"Political correctness is a doctrine, fostered by a delusional, illogical, liberal minority, and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end."
"For you who believe all you read, I caution you - you are daily being brainwashed for profit by extremely effective psychology with very little regard to factual accuracy. In short, you're at the mercy of the world's greatest bullshit artists with the morals of a stray tomcat." - Smokey Yunick
Stock tire diameter is approx 25.5".
Changing tire diameter will effect gearing and also speedometer calibration
But you would need a shorter tire to equal the effect of shorter gears like 3.73's.
A taller tire say around 27" would effectively give the car the feeling of having 3.23's.
And BTw the fuel mileage isn't as big an issue as one might think.
The effective rpm change from 3.42's to 4.10's at 70 mph in 6th gear is roughly 3-400 rpm.
Personally I wouldn't reccomend 4.10's in the stock rear.
Motive does make a 3.90 gearset for the 7.5" 10 bolt that would be more robust and offer a better trade off compared to the 3.73's.
Ok I thought stock 275x40x17 was 23.5" diam. but you did answer my question. about simply changing tires to give you effect of gear change.
sigpic
1998 Trans Am Convertible A4 - WS6 hood, WS6 air lid, WS6 rims, drilled/slotted rotors.
Stock tire diameter is approx 25.5".
Changing tire diameter will effect gearing and also speedometer calibration
But you would need a shorter tire to equal the effect of shorter gears like 3.73's.
A taller tire say around 27" would effectively give the car the feeling of having 3.23's.
And BTw the fuel mileage isn't as big an issue as one might think.
The effective rpm change from 3.42's to 4.10's at 70 mph in 6th gear is roughly 3-400 rpm.
Personally I wouldn't reccomend 4.10's in the stock rear.
Motive does make a 3.90 gearset for the 7.5" 10 bolt that would be more robust and offer a better trade off compared to the 3.73's.
To get a 3.90 ratio, they use an 11 tooth pinion and 43 tooth ring gear. So that is actually weaker. The 4.11s though I think that they achieve with a 9 tooth pinion, so I think that they are stronger.
2011 Mustang GT
20" Satin Black AMRs with 305/35 & 275/35 MT Street Radials, Saleen Grille, CS Lower Valance, Roush Axleback, GT500 Spoiler, resonator delete
so what if i had 20" wheels on my SS (never would...imo i think it looks silly) and say a 3.73 gear...would that be contradicting eachother since im shortening the gear and increasing the diameter of my wheels? I think the wheels are starting to turn in my head and im actually learning stuff....havent had this happen since high school!!
so what if i had 20" wheels on my SS (never would...imo i think it looks silly) and say a 3.73 gear...would that be contradicting eachother since im shortening the gear and increasing the diameter of my wheels? I think the wheels are starting to turn in my head and im actually learning stuff....havent had this happen since high school!!
Ok! this should spin your wheel, and mind. I based this on 23.5 diam. tire. That is what I saw posted as diam of 275X40X17 tire. the circumferance would be 43.765" times rear ratio 3.42 = 148.803" per revolution
3.73 = 163.242" per revolution
4.10 = 179.436" per revolution
so increasing tire diam. by 2" to 25.5 diam = 49.531" times 3.42 rear
3.42 = 169.390" per revolution
So my concusion on a stock 3.42 rear put 2" bigger tire and is same as between a 3.73 and a 4.10 gear rear end.
.
Last edited by 98blackbeauty; June 6th, 2009, 09:06 AM.
sigpic
1998 Trans Am Convertible A4 - WS6 hood, WS6 air lid, WS6 rims, drilled/slotted rotors.
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