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WOW goodbye gas mileage. Thanks for the heads up. That will come into the equation when I go to get this mod if anyone ever creates one for us.:rep:
 

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so instead of being at 2200 @ 65 I would be cruising at 65 wirh 3000-3200 RPM?
NO!

Going from a 2.82 to a 3.08 will not increase your RPM's by 800-1000.

As an example - ASSUME direct drive no drivetrain slip no overdrive

With the R/T gear @ 65MPH you'd turn 2799 rpm.

Change that out to a SRT rear and @ 65 you'd turn 3057 RPM.

So the gear change will add 258 rpm or so.

Now you can manipulate your car to thinkit had a gear change by changing the overall tire diameter. Want a car that is quick to accelerate, then put on a shorter tire. Want to run fast and long, then put on a taller tire.

Everything is relative to everything else.

rpm=mphxgrx336/tire dia.
mph=rpmxtire dia./grx336
 

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NO!

Going from a 2.82 to a 3.08 will not increase your RPM's by 800-1000.

As an example - ASSUME direct drive no drivetrain slip no overdrive

With the R/T gear @ 65MPH you'd turn 2799 rpm.

Change that out to a SRT rear and @ 65 you'd turn 3057 RPM.

So the gear change will add 258 rpm or so.

Now you can manipulate your car to thinkit had a gear change by changing the overall tire diameter. Want a car that is quick to accelerate, then put on a shorter tire. Want to run fast and long, then put on a taller tire.

Everything is relative to everything else.

rpm=mphxgrx336/tire dia.
mph=rpmxtire dia./grx336
Here we go with the math again.
ok help me figure this equation out
rpm= Rev. Per Minute
MPH= easy enough
gr =?
tire dia= easy enough
336= ?
 

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Some more interesting facts.

The 2007 Daytona has a 3.07 rear gear according to Chrysler.

The SRT's have a 3.06 gear for all years.

Now if the SE and SXT rear is the same rear as found in the Daytona, then hold on!

The SXT has a 3.64 rear gear!
The SE has a 3.90 rear gear!

I'd upgrade (if that is what it is) to the SXT rear in a heartbeat if the rear is found to be the same exact rear as in my Daytona. The increase in rpm's should rise around 7-800. On second thought perhaps an aftermarket TQ would be better.
 

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Really. So your saying that the SXT and SE gears are bigger than that of the Daytona/R/T and the SRT, therefore they would be producing a high power/HP ration to the ground then the Daytona/R/t/SRT's? Basically saying that SE and SXT has better gearing than we do?
 

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GR=gear ratio

The 336 is the required number in the formula to make it work

So 65 (mph) x 2.82 (gr) x 336 = 61588.8

Then divide that number by your measured tire height (I assumed 22 inches)

61588.8 / 22 = 2799.49(rpm)

Now I don't know the overdrive ratio off hand for the trans, but you would take the GR x the OD number to get the final drive ratio. So if the overdrive is .78 then your new gear ratio to use in the formula would be (rear gear) 2.82 x (overdrive) .78 = 2.2

I'm sure you see where this is going.
 

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Really. So your saying that the SXT and SE gears are bigger than that of the Daytona/R/T and the SRT, therefore they would be producing a high power/HP ration to the ground then the Daytona/R/t/SRT's? Basically saying that SE and SXT has better gearing than we do?
Yes BUT that is to compensate for the lack of HP the motor puts out. It is a very common thing to do in the auto industry.

A stock 4 cylinder Jeep comes with 4.10 gears, a 6 cylinder Jeep came with 3.23. They do this because the smaller motor needs help to get the vehicle moving (torque) and that is where gear ratios come to play.
A common Jeep swap to for better gearing off road, swap 4 cylinder axles for your current 6 cylinder.
 

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Discussion Starter #32
In a perfect world, I would think the 3:08 to be the optimal compromise between off-the-line get-up-and-go and rpm at cruising speed. We just exchanged our 18" wheels for 20" Magnum SRT wheels which added about an inch to the overall tire diameter. We have done NO performance mods yet, and would like to see a little better low RPM torque. I'm not looking to perform 50' burnouts, but a little better acceleration from the stop light would help.
 

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Surprised that nobody has mentioned it, a higher stall torque converter. You will jump off the line quicker, and still be very streetable as a daily driver
 

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A higher stall torque converter should knock off .3-.5 tenths your 1/4 mile et.

If the SE and SXT rears are identical, I'd swap the entire unit out. It would be simplier than setting up new gears.
I'd go with the larger tires, 3.64 gear and a aftermarket TQ for the best of all worlds. How often do you go really fast for long periods of time. My Daytona shifts out of 4th gear into 5th gear at 140 mph, so I know the car can handle more gear.
 

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I have been told that with a higher stall torque converter that a oil cooler is necessary, any truth to this?
 

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I have been told that with a higher stall torque converter that a oil cooler is necessary, any truth to this?
Yes and no. It really depends on driving style.
Heat is the biggest killer of an auto trans. The stock converters with all the slippage allow a lot of heat to generate. These higher stall converters are "tighter" and produce less heat in a sense, so they should actually make your trans last longer in theory.

I'm sure we could get away without not having to add an additional oil cooler. Having a temp gauage or indicator ligth would help with peace of mind if you're really concerned, I wouldn't be though. Some of those people that live in hotter climates may need to do an aftermarket cooler if they really abuse their car.
 

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A confusing thing about torque converters is the way the stall works. When you get a "custom" converter it is designed to stall at your maximum horsepower level. So if your car makes 300 hp and it is designed to stall at 3500 rpm it will stall at that speed when it hits that hp level.
Most of the time when driving you're not at your maximum horsepower level so the stall speed actually drops way down. So if your crusing on the highway your hp level may be around 150 so the stall drops to 1400 rpm.
Conversely if you add hp to your motor the converter will stall at a higher rpm, say if you add 125 hp to your motor then the stall will go up to 4000rpm.

That is the easiest way to explain it, but their is a lot of voodoo involved.
 

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Shortly after getting this car I called Chrysler's Support Line, gave them my VIN, and they sent me the Build-Sheet with everyhting that went into it. I just looked it up to re-check, and I was incorrect. The Build Sheet lists it as "2.82 Drive Axle" (Build Code-DMBS)
Would you post the link you reference to in this post. thank you
 

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No one ever looks lol.....you just necromanced a 13yr old thread, quoting a guy who hasn't posted here since 2010 🤣 🤣 🤣 🤣 🤣 🤣 🤣 🤣
A simple Google search or search of the forum itself would've netted you what you needed.
 
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