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Gearing question for auto cars... 60ft and 1/4 mile thoughts

2015 Silver GT

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That is because that is what the cars come with stock. I don't think there are enough people running taller gears to know if it is better or worse.
If guys thought gears would help they'd do something about it. But they're not.

The fastest N/A car went from 3.73's down to 3.31's and ran a faster time. Coincidence? I doubt it.
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Tommy V

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If guys thought gears would help they'd do something about it. But they're not.

The fastest N/A car went from 3.73's down to 3.31's and ran a faster time. Coincidence? I doubt it.
And he has a convertor,RIGHT????U know what a convertor does???
 

2015 Silver GT

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And he has a convertor,RIGHT????U know what a convertor does???
Yes I do, I ran a Circle D 4C. That helped me run low 11's N/A with 3.15's. How fast have you been?
 

Tommy V

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Yes I do, I ran a Circle D 4C. That helped me run low 11's N/A with 3.15's. How fast have you been?
10.603 10.604,726rwhp manual.And u just stated a convertor helped u get a low 11 na.A convertor works simular to gears as it slips letting torque be in the opitium range..My slips are in the drag section under new pb runs,along with quite a few guys on here that know what my car runs.
 

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Tommy V

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They accomplish the same task,get car in the best torque range to get the car moving.How they do is trivial,u need one or the other or both if u want to get a heavy car moving.Maybe if u listen u would have went faster then 11,s:D
 

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Dang not trying to be a smart ass but I just actually learned a lot in this thread from you two arguing lol.. guess I'll be keeping my 3.15 gears now.
 

Tommy V

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Dang not trying to be a smart ass but I just actually learned a lot in this thread from you two arguing lol.. guess I'll be keeping my 3.15 gears now.
Oh yea what did u learn??
 

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im not saying it cant be done, but look at the 1/4 mile list and look at what all the fastest cars have in common.
 

1badrz28

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im not saying it cant be done, but look at the 1/4 mile list and look at what all the fastest cars have in common.
My guess would be these guys bought their cars with the most common gear available and quite honestly, it's too hard for most to the change gears. So they run what came with the car and opted not to change them out. The car should use the gear for the mph it wants to see in the 1/4 at or around the specified red line the engine is built for. That will keep the car in the power band. Converters will help get the car to the desired rpm to use maximum torque to get the car moving. if I didn't street drive my '17 and it was track only. I'd probably have a 5-6500 rpm converter in the car to eat up those lower rpms that aren't making any power.

If the 3.15 gear has the car at 76-8000 rpm in the specified gear at the end of the 1/4 mile that would be the right choice. If not, the car could accelerate better with a steeper gear given traction is the same. It may only be a .1 gain in ET in some instances, but too some in the heads up game, that's worth the cost.

I've changed many gear sets running x275/10.5 races and the best et always was with the correct gear for the mph and rpm I was seeking in either the 1/8 or 1/4 mile.

Add all three gears on this link and it seems most are using 3rd gear. See where you fall. Right now being na 3.55 it comes out to 119 mph at 8000 rpms. That's about right for my application. The 3.15's come out to 134 mph and the 3.73's are at 113 mph. Adding a power adder changes the whole game, but may also need the 4th gear and that's where you need to look at the gearing options again.

http://www.wallaceracing.com/gear-speed.php
 
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My guess would be these guys bought their cars with the most common gear available and quite honestly, it's too hard for most to the change gears. So they run what came with the car and opted not to change them out. The car should use the gear for the mph it wants to see in the 1/4 at or around the specified red line the engine is built for. That will keep the car in the power band. Converters will help get the car to the desired rpm to use maximum torque to get the car moving. if I didn't street drive my '17 and it was track only. I'd probably have a 5-6500 rpm converter in the car to eat up those lower rpms that aren't making any power.

If the 3.15 gear has the car at 76-8000 rpm in the specified gear at the end of the 1/4 mile that would be the right choice. If not, the car could accelerate better with a steeper gear given traction is the same. It may only be a .1 gain in ET in some instances, but too some in the heads up game, that's worth the cost.

I've changed many gear sets running x275/10.5 races and the best et always was with the correct gear for the mph and rpm I was seeking in either the 1/8 or 1/4 mile.

Add all three gears on this link and it seems most are using 3rd gear. See where you fall. Right now being na 3.55 it comes out to 119 mph at 8000 rpms. That's about right for my application. The 3.15's come out to 134 mph and the 3.73's are at 113 mph. Adding a power adder changes the whole game, but may also need the 4th gear and that's where you need to look at the gearing options again.

http://www.wallaceracing.com/gear-speed.php
but your X275 car is shifting once or twice, a 1000whp car seeing a trap speed of about 150mph in the quarter, the 3.15 is the correct choice to only shift twice. past that they are shifting into 4th and out of the powerband or crossing the line 3000rpm below redline.

i get what you are saying, and the big HP guys are going 9 inch just for ease of gears, but youre asking for $5000 to gain .1 or .2 in the quarter, which almost 0 people here are willing to do.
 

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my car is a 15 auto centri with 3C converter 3.15 and STOCK halfshafts....1.33 60ft. i think the 3.15 works great...i just ended up doing the dss 1400hp shafts and retiring my stock shafts intact and good as the day i got the car....i think my car would 60' worse if i had steeper gears....further more i would never trade 1/8 for back half mph....id rather have a killer 60' then a mehhh 60' and make it up on the big end with mph....especially in an auto car the thrill is all off the line anyway...once your in 3rd its essentially a wot highway pull, if i could i would even go to a 3.08 as the only draw back i see with the 315's (atleast in my car) is that it shifts 4th just before the end...
 

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my car is a 15 auto centri with 3C converter 3.15 and STOCK halfshafts....1.33 60ft. i think the 3.15 works great...i just ended up doing the dss 1400hp shafts and retiring my stock shafts intact and good as the day i got the car....i think my car would 60' worse if i had steeper gears....further more i would never trade 1/8 for back half mph....id rather have a killer 60' then a mehhh 60' and make it up on the big end with mph....especially in an auto car the thrill is all off the line anyway...once your in 3rd its essentially a wot highway pull, if i could i would even go to a 3.08 as the only draw back i see with the 315's (atleast in my car) is that it shifts 4th just before the end...
Yes and thats a great combo with the right convertor,my argument was say take your convertor out and put the stock one back in with them 315 gears and see how it 60 ft.I was telling the other guy im arguing with that if u have 315 gears and even with a centri blower the only way to really get the car moving was one 1 change gears or 2 put a convertor in it,either one will get the car to 60 ft better.Some guys dont have $1200 to dump on a convertor but can spend $200 for a set of gears.This all started with the comment that gears wont make a 6r80 auto faster and thats not true.By the way that vortec u had was rollin,have u sold it yet and whats next?
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