Rear end gear too tall

[CaliSting]

...with every one focused on boosting power to get better 1/4 mile times no one seems to be addressing elephant in room. Rear end gear is too tall. To make our cars a lot faster seems we would have shorter rear end gear . I’d say our cars could smash 0-60 of under 4 and get into high eleven 1/4 with shorter rear end gear.

Of course this will mean higher rpms when cruising and top speed of 167 reduced but car will go like bat out of hell 0 to 100. Just curious why not many of you drag racers have been talking about getting somone to make a new gear for rear. Also curious if Hyundai twins have a compatible rear end and if they might have a different gear?

 

[Kamauxx]

Many of our cars are already capable of hitting 60 in under four with simple, cheap, removable tuning options.

Simple, cheap, and removable. That's why gear swap isn't on my radar.

 

[Ucinn]

I thought they were already pretty short with 3.54's and 3.73's in the 2.0... those are pretty short for an 8 speed.

 

[eflyguy]

Agreed.. and the loss of traction during shifts kind of proves that.

 

[DaJackson]

Because no one is building a drag car. Haven’t seen anyone that isn’t daily/regularly driving their car and losing significant MPGs at cruising speed isn’t worth a couple tenths in the 0-60.

Also as @Kamauxx, swapping a rear end isn’t easy or cheap.

 

[KLR STINGER]

I thought they were already pretty short with 3.54's and 3.73's in the 2.0... those are pretty short for an 8 speed.

This. Effective 1st and 2nd gear ratios are already very short. They are already pretty well balanced for torque multiplication and RPM/speed. Top speed in these cars is drag/power limited not gear limited. Theoretical top speed for a GT would be 267mph based on gearing, 26" tire and 6800 RPM. In the modern 8+ gear transmission world, final drive shortening is no longer necessary as the first/final combos are already very steep.

 

[CaliSting]

Don’t need to be building drag car to take advantage of better gearing. Been putting better gearing in my street cars for years . While 2.0 has ok gearing the 3.3 could use better gearing to go even faster. My car is tuned and I don’t lose traction with all nannies off . We would need to be pushing in excess of 600 hp to use gears we have now.

Just saying it’s an opportunity to get some free torque in 3.3 cars. Not talking to people who aren’t speed enthusiasts not willing to make real commitment to going fast. Somone out there will do this eventually I’m betting.

My 370 Z with shorter rear end gear was so much faster it was crazy.

 

[Kamauxx]

Just saying it’s an opportunity to get some free torque in 3.3 cars.

Poor choice of word.

 

[Ucinn]

My mustang is much better after I went from 2.73's to 3.73's but even with a 6 speed first gear is darn near unusable in regular driving it's so short

 

[Kamauxx]

It's also going to make the fuel economy worst. In a car advertised as a "Grand Tourer" I'd like to get over 350 miles on the hwy before the gas light comes on. That's already a chore with the stock gears since Kia decided to have a matchbox sized fuel tank in the Stinger.

 

[CaliSting]

It's also going to make the fuel economy worst. In a car advertised as a "Grand Tourer" I'd like to get over 350 miles on the hwy before the gas light comes on. That's already a chore with the stock gears since Kia decided to have a matchbox sized fuel tank in the Stinger.

I'm not part of crowd who has bought into overly hyped "Grand Touring" car marketing PR. Car misses mark significantly as a traditional Grand Touring car. Especially for those of us coming from luxury brand GT's from Europe and Japan. Car isn't that comfortable for long trips and Kia made lots of decisions to put performance elements on car not needed in Grand Touring car. Mechanical LSD? Quick steering ratio? and as you say dinky fuel tank. LOL! There are some of us more enthusiast minded owners looking to put more aggressive suspension under car, tune for more power, upgrade gear ratios, bigger wheels and tires. So more aggressive rear end isn't something out of realm for me. ...and Kia is watching what we do in Aftermarket guys. Germans there have already said they are seeing what we do and it a more enthusiast version of car will be made. People like me will be crowd who drive Kia to consider these more enthusiast upgrades. A Kia Stinger GT-R may be in cards. If not I will have one by my making.

Putting a slightly more aggressive rear end gear in car isn't going to adversely impact car. Would have minimal impact to MPG. Did same on my Porsches and Nissans and didn't make cars miserable to drive or impact MPG overly? We already have very tall final gear in car so its not like car will be buzzing down freeway! LOL!

Look at how quick my street legal car with shorter rear end was off a turn in Hillclimb.

 

[KLR STINGER]

Shorter diff gearing will definitely improve in gear acceleration and be fun on the street and certainly add performance. Just won't be worth it to most and the AWD guys would be out of luck. I Don't think a 3.55 is a particularly tall final drive, especially especially with the steep 1-3 ratios, but after 5th your in overdrive territory and shorter gears would be beneficial. I just doubt there are enough people interested and market available to make custom gear set an option. If the differential housings are the same, maybe a 3.73 from the 2.0 might fit, but its maybe not enough of a change to make it worth while. Then there is the tuning consideration. Given the stinger only comes in an auto, you need to be able to tune the TCU for the ESP/TC not freak out. Bottom line, while gears are on some cars and easy/cheap performance upgrade, I don't see that happening on this platform any time soon.

 

[eflyguy]

I would expect traction to be a problem if it was any shorter. I think as it is, it allows you to use most of the power on the street regardless of conditions, which is what it was designed for. It can be a lot of fun to drive cars with shorter rear gearing, especially RWD, but that's not the market this vehicle was created for.

 

[Helo58]

I may or may not do the things the OP is suggesting, but I have seen it done on other modern cars successfully and relatively cheaply. People who do city driving may actually offset highway losses by improved city mileage with the gearing change. It is hard to tell. I don't think traction would be adversely affected because many of us are considering a 20x10 rear wheel/tire. The gearing change will offset the additional weight (if any) as realized at the new outer radius of the tire. Additionally, the 10 inch wide tire will provide plenty of traction for the gearing and any "stage 1" level performance improvements. I also see a lot of people putting the Stinger in a box for some reason. The suggested mods I have seen will only make the car more of what it already is... a platform for a wide variety of people to drive, enjoy, and or mod. From extreme tuner to 2.0T premium highway cruiser, there is something for everyone.

 

[Kazz]

I'm guessing that Boxster, stock, didn't have the wheelspin potential this car does. The electronic nannies work really hard to keep them from spinning in the Stinger, but they still do.

 

[scharn]

I hope someone tries this, because it is interesting to read and options are never a bad thing.

That being said i'm always surprised what people choose to do with certain cars. The Stinger is a gran tourer in the sense that it isn't a nimble go-kart canyon carver, nor is it a drag car as you could do far better with lighter cars, less bells and whistles. People ask I refer to the stinger and tweener. It is in between so many different philosophies, styles, and size. More upscale than many cars, but not luxury. Larger than 3 series or a5, but not massive like a7, etc. Quick but not like m240i, or even s5. Handles pretty well but not planted to the road like those others. Comfortable but somewhat stiff ride especially if coming from some luxury brands.

I guess that good because you can turn into a lot of different things with some work, but you could start with other cars closer to fulfilling a specific desire.

 

[Helo58]

...The Stinger is a gran tourer in the sense that it isn't a nimble go-kart canyon carver, nor is it a drag car as you could do far better with lighter cars, less bells and whistles...

I think I simply want to squeeze the most out of the platform while maintaining all of the good qualities. The designers of the car answer to "bean counters," but I can do things without having to consider the financial impact, mass market appeal, and whatever other things OEMs have to consider when making a car for the masses. I will always embrace the "GT" role of the car, I simply want a faster and better cornering GT than the rest. The main reason I purchased the GT RWD LSD Stinger was because it was the lightest available with the 3.3TT. Others may want all of the extras like HUD, more speakers, sunroof, 8000 way adjustable ventilated seats, and more. I just wanted the looks and the powertrain. I think I am liking KIA's approach to how they marketed the GT/GT1/and GT2 more and more every day. There really does seem to be something for everyone.

 

[KLR STINGER]

I may or may not do the things the OP is suggesting, but I have seen it done on other modern cars successfully and relatively cheaply. People who do city driving may actually offset highway losses by improved city mileage with the gearing change. It is hard to tell. I don't think traction would be adversely affected because many of us are considering a 20x10 rear wheel/tire. The gearing change will offset the additional weight (if any) as realized at the new outer radius of the tire. Additionally, the 10 inch wide tire will provide plenty of traction for the gearing and any "stage 1" level performance improvements. I also see a lot of people putting the Stinger in a box for some reason. The suggested mods I have seen will only make the car more of what it already is... a platform for a wide variety of people to drive, enjoy, and or mod. From extreme tuner to 2.0T premium highway cruiser, there is something for everyone.

Without the ability to tune the tcm you cannot do this on these cars. This is not a Camaro or a charger. We do not have the volume of sales for an aftermarket ring and pinion set to be produced, not the ease of tuning those platforms offer. Its a good idea, but not realistic at this time

 

[CaliSting]

Think it’s time to dispel some myths. Plenty cars same size or bigger than ours with shorter rear end gear options. Most considered GT cars or even SUVs. BMW 5 and 6 series, Cadillac CTS, Dodge Charger and Challenger, Infiniti G37 sedan, infiniti FX45 crossover, even SUVs and trucks too.

Then let’s talk about size of Stinger compared to Camaro and Mustang. We are only a few inches longer then both of traditional pony cars and smaller than Dodge. M4 from BMW same deal. Stinger Actually more narrow than all 3 . Even GTR isn’t much smaller than Stinger. Our cars also have ability to shed couple hundred lbs easily without impacting day to day drivability.

Yes would have to determine if ECU tuning would be wacky if made slight change. Plenty of automatics out there with shorter than stock rear end gears.

...Add to this that we share platform with with G70 which is marked as more of performance car. Market should be there.

Can say my 370 z put power down with shorter rear end with over 500 hp and it had less weight over rear tires than the Kia.

All I can say is thankfully car is sold in Australia and we might see some crazy guys there break the mold and do something. I’d also bet money that somone will build a Stinger Drag car. ...it’s only a matter of time.

 

[Helo58]

Without the ability to tune the tcm you cannot do this on these cars. This is not a Camaro or a charger. We do not have the volume of sales for an aftermarket ring and pinion set to be produced, not the ease of tuning those platforms offer. Its a good idea, but not realistic at this time

Well, my ISF sold fewer units in 6 years than the Stinger sold in 6 months, so I understand the relationship of sales volume to aftermarket. The ISF had a limited but vibrant aftermarket that 4 years after production ended is only now seeing the first engine tune and supercharger application. KIA/Hyundai is nowhere near as protective as Lexus was over the ability to tune the ECU or TCM, yet someone found a way. I appreciate what you may consider being "realistic" but to someone who has seen a far worse scenario and good parts come from it, it just sounds pessimistic. I imagine that the ability to tune the TCM is weeks away, not months or years. The first ECU tune is already out while still in the first model year. As far as ring and pinion, again optimistic. Parts like that are way more easily made these days in smaller batches than 10 or 20 years ago. I am sure that someone will meet the need in short order if it is determined there is a need within the community.