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Premium Member
TrailblazerSS
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3,290 Posts
Discussion Starter · #1 ·
is it true that if we put a 4l80e trans in our trucks wit the stock 4.10 gears its like have the 3.42's. i thought i seen it some where on here just dont remember. now my question is if it is true what gears could i/we put in the rear end to make it lik the 4.10's that we hav. would it be 4.56 or what ??? thanks
 

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Premium Member
07 TBSS 1SS AWD
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17,281 Posts
you would need to know the final drive ratio of 4th/OD to be able to figure it out for sure...

i would love a custom gearset for my 70 that is more over driven with a lower first gear... then put a 456 or a 513 in my truck...



 

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Premium Member
'07 awd
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2,422 Posts
The gear ratios for a typical 4l80 are: 1st-2.48, 2nd-1.48, 3rd-1.0, 4th-.75. For the 4l60/65/70 they are: 1st-3.06, 2nd-1.63, 3rd-1.0, 4th-.70.

So the gearing would be diff, but wouldn't be "just like" swapping in 3.42s. I'll let you do the math for each gear on each trans for the overall ratio per gear.
 

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Premium Member
TrailblazerSS
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3,290 Posts
Discussion Starter · #5 ·
No I am putting in a 4l80e in an I thought I read sum where that the 4l80e gear ratio is lik putting in 3:42's. I lik how the truck is wit 4:10s an the 70e trans but I'm not putting another weak trans in my truck so I'm goin the 80e if that makes since
 

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Old but not Dead Yet!
TrailblazerSS
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9,572 Posts
Makes sense to me, just wish I could afford to do the same but gearing wouldn't be much different.
 

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Premium Member
'08 TBSS 2wd
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1,496 Posts
With an 80e, you'll have less acceleration in 1st than you would with the 70, and less overdrive than you would with the 70. The overall 1st gear ratio would be like a 70e w/3.42s...you can do the math by multiplying the trans gear ratios by the axle ratio. The one good thing about the ratios in the 80e is that it allows for less rpm drop between shifts. Make no mistake, your truck will be slower with an 80 in it. If you only have a few bolt ons, I wouldn't do it. I'd only go 80e if I were forced induction making big power. A properly built and tuned 4L70e is plenty for a bolt on truck.
 

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XPTBSS
TrailblazerSS
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4,249 Posts
The 80E in first gear is very different. If you were cammed you probably liked 30 rolls. Now with an 80E it would be 40 rolls or 60 rolls in 2nd. I love my 80E. I made up for the 1st gear with a higher stall converter. This thing is nasty :)

3rd gear is when this thing comes alive though! Much better top end.
 

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Bad Monkey Racing
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1,559 Posts
Here is a little chart I did a while back when thinking about swapping my gears around. It shows the gear ratio based on transmission and the speed it should reach with teh BFG's I have. It will giv eyou an idea of what the differences are and th gear ratio's used.

 

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Premium Member
2007 AWD - 3SS TBSS
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2,617 Posts
...i would love a custom gearset for my 70 that is more over driven with a lower first gear... then put a 456 or a 513 in my truck...

PATC has developed a new 6 pinion planet gear set for 700R4 / 4L60E / 65E /70E, that does just that:
http://www.transmissioncenter.net/competition.htm

700R4 / 4L60E "Power Gear"

2008 / 2009 - "The Next Big Thing". PATC has developed a new 6 pinion planet gear set for 700R4 / 4L60E transmissions. This will be the biggest thing in 700R4 advancements in years. These will have a 2.84 to 1 first gear, 1.56 to 1 second gear, 1 to 1 third gear and .70 to 1 overdrive ratio. This close ratio 700R4 gear set will have a 11.72% less RPM drop between 1st and 2nd than the wide (stock) ratio gear set. In other words the close ratio gear set will only have 88.28% as much RPM drop as the wide ratio gear set. This is what people have been asking for, for years. These will work on any 4L60E type transmission without a gear ratio error code, if the PCM is modified. The carrier is made from E4340 billet steel and the pinion gears are 9310 steel. With the billet sun gear made from 9310M steel. This gear set is used to reduce torque multiplication / rotating speed in the transmission in first gear. This improves track applications that overpower the rear tires upon launch. This is common with numerically high final drive ratios. Now you will have a choice between the wide ratio or the new close ratio gear sets. In first gear this close ratio gear set has a 7.2% numerically lower final drive ratio. It has been reported that the 2.84 gear set could lower your quarter mile time as much as 4/10 of a second over the 3.06 gear set. This gear set has been in research and development for over one year. You might ask why 6 pinion gears. The answer is because high horse power motors can eat the small needle bearings up in the pinion gears. The solution is to spread the load over 50% more needle bearings and at the same time building the planet gear set out of a higher grade steel. The first 50 are in production now and the approximate release date is May 2009. We have finished the testing in our test truck with the following findings. The gear noise in manual low is reduced by at least 50% compared to a stock OEM planet gear and at full throttle there was no noticeable power drop on the 1st to 2nd shift. Testing will begin later this week in an 1100 horse power C5 Corvette. The car runs 9.56 seconds now. Nothing will be changed but the front planet gear then tested to see the difference. Testing should be completed by 6-1-2009. Patent Pending

Here are the test results from the weekend of May 30-31, 2009. Both where run for the base time then nothing was changed but the front six pinion planet gear then retested to determine the time difference.

The first car is a C5 Corvette with an 1100 horse power blower motor. The best time with the factory planet gear was 9.56 and the time with the new 2.84 six pinion planet gear was 9.25. This is a whopping 3/10 of a second faster in the quarter mile. The time would have been even better if the 3-4 clutch wouldn't have been slipping. Perhaps as much as 1/2 second better then the factory gear ratio.

The second test was with a 460 horse power all-wheel-drive Chevy Cyclone. The best time with the factory planet gear was 13.10 and the time with the new 2.84 six pinion planet gear was 12.90. This is a whopping 2/10 of a second faster in the quarter mile. There was 300 to 400 less RPM drop on the 1-2 shift with the new gear ratio. This truck didn't have a problem with tire spin on take off because it has all -wheel-drive. The 2/10 of a second was picked up on gear ratio change only, not on take off.

Update 6-3-2009: Three more reports have come in with 3/10 of a second or more off of their E. T..

This gear was built for the 1982 on GM 700R4 family of transmissions only, that includes the 700R4, 4L60, 4L60E, 4L65E and 4L70E model numbers. For drag racing purposes the 700R4 has too large of a gear ratio spread between first gear and second gear resulting in too large of a RPM drop between gears resulting in a large torque drop (loss). With the new 2.84 gear (1st gear ratio) there is approximately 500 less of a RPM drop on the first to second full throttle shift depending on the RPM of the 1-2 shift point. This gear change also results in a 4% less RPM drop upon the second (intermediate gear) to third (direct drive, 1 to 1 ratio) shift.

The purpose of this gear is keep the torque at a higher point on the torque curve when shifted to second gear from first gear resulting in a faster elapsed time in a quarter mile. The front planet gear controls the gear ratios of first and second gear. The 2.84 to 1 gear ratio in first is accomplished by using a larger diameter sun gear and a smaller diameter pinion gears. At the same time the pinion gear carrier and the sun gear are made from a higher grade steel to handle motors with higher horse power and torque levels. In addition one or two additional pinion gears are added (total of six) to spread the load (torque) over a larger area and to accommodate more pinion gear needle bearings. (The OEM stock front planet gear set has 4 or 5 pinion gears.)

In testing it was found to result in at least a 3/10 second improvement in elapsed time in two wheel drive cars and at least a 2/10 second improvement in elapsed time in all wheel drive cars. As an added bonus the 2.84 first gear ratio has less tire spin that the 3.06 original equipment first gear ratio making 2WD cars faster on take off. For the purposes of the 700R4 transmission the 2.84 gears set would be called the close ratio gear set and the 3.06 original equipment first gear ratio would be the wide ratio gear set. A wide ratio gear set would be better for towing and a close ratio gear set would be better for racing. There are other transmissions with 2.84 first gear ratios or six pinion gears but not for the 700R4 family of transmissions.

Trans Ratios 1st to 2nd 1st - 2nd - 3rd - 4th/OD
------------Ratio Drop -Gear Gear -Gear - Gear
"Power Gear" - 1.28 -- 2.84 --1.56 -- 1 -- 0.70
700R4/4L60E - 1.43 -- 3.06 --1.63 -- 1 -- 0.70

 
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