Pontiac G8 Differential Comparison

2009 G8 GT differential comparison. Stock 2.92 differential with stock diff and rear cradle bushings vs 2010 Camaro SS 3.45 differential with BMR Pro-series diff bushings and Street-series rear cradle bushings.

[@wolfman1192]

Thanks for putting this video together! I have had just a Rotofab CAI and underdrive pulley with a tune for a while, but the car is in the shop getting Kooks LT'S, 3.27 LSD and all the BMR goodies. Should be a completely different car once I apply the new tunes....this video made me feel more confident that 3.27 was the right choice.

[@1luhset564]

Any other mods on your g8 ?

[@MrXr8260]

Excellent vid exactly what I was looking for thanks

[@m.pietro9087]

Thank you for the video. Very good comparison.

[@isaacb21]

Very well done video. Car sounds great BTW

[@36penney36]

Very well done video. Thanks for the comparison.

[@LEO8er]

Tazrock and 36penney, thanks for the comments. Tazrock, I would recommend, at least, tuning your transmission with a differential swap to ensure the shift points are ideal for the new gears. I don't think it will hurt anything if you don't though. I had the differential installed by a friend who is also my (and my club's tuner/performance tech). He had it done in about a day with no lift. Aaron, I did not use any professional timing equipment to time the car and simply did so via the video while editing it. I've read stats that list the 0-60 times between 5.1 and 5.9 seconds and 1/4 mile times between 13.6 and 13.9 seconds. My car did have a trans tuning issue that would not allow me to power brake and may have limited the actual launch, but still allowed me to pull a 13.256 second quarter mile time with the listed mods. This was corrected after the differential was installed and the trans was re-tuned. Also remember that cars are not identical and will have variations in performance....especially when considering weather conditions. I live in a very humid, southern climate and such weather could greatly impact a vehicle's performance in a negative way.

[@gdubm4]

Great vid!!! Thanks for posting this info.

[@roberthansen1023]

Did it feel more torquey in the low end? Also, do you know what the part number was for the new diff? Thanks.

[@dangerousfreedom4965]

Well done sir👍 Very well done!

[@ryanrobitaille5903]

Big time difference just in staying in 5k rpm right there between shifts hits that shift quicker too dang

[@willbray3462]

How did you go about obtaining the 3.42s ....new? used? rebuilt? got rid of the 5th gen to buy a truck and came across a gem of a GT and its bone stock under 60k miles. Premium. Sport. 09 and i Love This Car.

[@dangerousfreedom4965]

Great vid thank you

[@fursol]

Thx for posting

[@blushirt35]

Hi Leo....great video by the way, I am noticing that when you punch it you arent spinning everywhere with the 3.45 which is my concern. how is it when you launch and how has MPG been??

[@LEO8er]

blushirt35 You are correct. I wasn't spinning much from a launch because the intake I had installed was causing the engine to dump a TON of fuel on the launch. This essentially drowned the motor and caused the car to fall on it's face from a dig. I have since replaced my intake with a Vararam and have had the engine re-tuned. Spins like hell now on the street even with traction control on. I haven't had traction issues on street tires at the track, though. MPG has fallen a bit, but I attribute most of that to my more aggressive driving style.

[@TheGhettoRdneck]

Did you have to reprogram anything or just swap the diff and bushings out?

[@LEO8er]

Definitely feels more "torquey" especially from a dig. No idea on the part number since I bought it from a friend in my car club.

[@roberthansen1023]

Thanks

[@aaronsuek]

Are you sure you timed the stock 0-60 and 0-100 accurately? I timed them as ~5.3s and 12.6s, respectively, which is roughly what the stock numbers should be.

[@MrDerekRobinson]

They're milliseconds. It can be anything depending on when you start and stop the counter at

[@MrDerekRobinson]

Oops. 6 year old comment lol nevermind

[@Papichris_559]

I installed 3.91 (1le) gears on my 2010 camaro ss and loved it! Was thinking about doing the same to the g8 but not sure how it'll be. Has anyone else don't the 3.91's?

[@BornToBeFamed]

Chris papi i would. When i get a g8 lol i want 390s its a perfect match

[@nickblets69]

Nice video. Do you know if the 292 G8 diff and the 345 Camaro diff use the same diff oil specs

[@adambaker1404]

I dont think so

[@apiquant2]

I just purchased the same differential is everything both on... beside the BMR bushings

[@LEO8er]

yes

[@CISCO485]

would the gxp dif and gears be a good enough swap for my gt? or should I go the camaro route?

[@LEO8er]

Cisco Blank The gear ratios in the GXPs are 3.27 for the autos and 3.70 for the manuals. Both would work for the car depending on your long term plans. 3.70s (and even 3.45s) are too much for boosted cars based in what I've discussed with several tuners. The benefit to the Camaro diffs is that they are physically bigger and "beefier" than the ones from the GXPs. They tend to be stronger as a result and they have a wider array of gear and pinion options for a possible rebuild.

[@apiquant2]

I purchase the BMR bushings do I need anything else special to install the diff.... nd does my axles fit inside the differential,,,

[@LEO8er]

The only other thing i would recommend changing is the gear fluid in the diff. Axles will fit.

[@SRfastZ]

Good video

[@ApexMissingApe]

Great video. I really want to swap mine to a 3.45 but that 2400 RMP at 80 scares me. I'd constantly be at the gas pump. Do you know about how many fewer MPGs you get on the highway now?

[@LEO8er]

Apex Missing Ape I know a few people who did that and felt it was too much. Especially without further power upgrades. Wound up dropping to 3.27s.

[@dangerousfreedom4965]

LEO8er are you saying you swapped to 3.27 gears?

[@dangerousfreedom4965]

Or that you know someone that did?

[@dangerousfreedom4965]

Florida?

[@superflashXXX]

someone school me. why are the revs lower with a stock smaller dif? i thought theyd be lower with a bigger dif.

[@LEO8er]

superflashXXX "What Is a Gear Ratio? When you hear people refer to numbers like 3.08, 3.73, or 4.10, they’re talking about the ratio of the ring-and-pinion gears in the rear axle-hence, the numbers are more accurately 3.08:1, 3.73:1, or 4.10:1. The ratio is the number of teeth on the driven gear (ring) divided by the number of teeth on the drive gear (pinion). So, if the ring gear has 37 teeth and the pinion has 9 teeth, the ratio is 4.11:1. That also means that for every one turn of the ring gear, the pinion will turn 4.11 times." www.hotrod.com/articles/how-gear-works/

[@LEO8er]

superflashXXX That said, the difference in rotation between the stock 2.92 gears and the Camaro 3.45 gears is 0.53 turns on the drive gear. Since this is the one driven by you motor/transmission, you get higher revs. The bigger gears are better for acceleration while the smaller ones are better for top speed because you get more rotation on your tires more quickly. It reduces the load on the drivetrain.

[@LEO8er]

superflashXXX I've actually noticed the difference in my trap speed at the track. before the gears I was hitting between 111 mph and 113 mph. Now I run a faster time at 109 mph.

[@AdussFadass]

I don't know it your were giving it WOT or not with 2.92 gears but it took a long ass time to get to 80mph.

[@LEO8er]

If you are referring to the on ramp, I was not full throttle.

[@AdussFadass]

LEO8er Got it thanks.

[@jonasgrumby1093]

Feels like a different car

[@813poptop]

Great video! What exhaust setup do you have?

[@LEO8er]

Thanks! I have a Kooks headers and SOLO Performance setup. Here's the quick comparison video. I also have a longer version that shows the difference in sound while driving. kzbin.info/www/bejne/poi0gKScrb1motU

[@LEO8er]

Here's the longer version. kzbin.info/www/bejne/aXXReZmOmK5qaqM

[@813poptop]

Awesome, thanks!

[@USDM_Jesus]

Quick question. Doesnt this lower the g8s top speed?

[@LEO8er]

Yes

[@pontiacmaniac7772]

Can I just swap my gears or do I have to get a whole new rear end?

[@LEO8er]

You can, but you'll get a bigger/beefier gearbox by swapping to the Camaro.

[@dangerousfreedom4965]

You still have your G8? Your in Apopka FL?

[@LEO8er]

407ForRent I do

[@geffarigarage]

how much whp your g8 making?

[@LEO8er]

Around 357 at the wheels at that time. Probably closer to 365-370 with a better intake and a refined tune.

[@fursol]

Do you need to tune the car after the swap? and how much time it take to swap? thx

[@adambryant3546]

Thats what I was wondering. Did you have to retune?

[@dangerousfreedom4965]

Part numbers

[@micheloliver2941]

Which exhaust pipe you have

[@LEO8er]

Solo Performance Mach Shorty Balanced

[@micthegreasemonkey2918]

Hi stall torque converter would b nice.

[@LEO8er]

It would be nice for drag racing, but that's not what I'm into. I prefer auto-x and road racing and a hi stall converter could be a be treacherous on acceleration out of corners.

[@jasonm9264]

Your 0-60 are way slower than stock with the stock gears. Who wrecked your car? Mine with just cold air and cat back does 0-60 in 5.2.

[@LEO8er]

+Pseudo Mortality My car has only been rear ended and it suffered no mechanical damage. As you can imagine, there are numerous variables that affect the performance of vehicles and their numbers. Generally speaking, no 2 cars have the EXACT same performance.....even when tested directly from the factory. The 0-60 times I've seen posted for the G8 GT range anywhere between 5.3-6.2 seconds depending on the driver, location, and weather conditions. Additionally, I was not using any precise timing equipment in taking my measurements and was simply counting the frames of my video in conjunction with the video timer. In addition to this, I had a few issues with my tune as my car was one of the first 09.5 GTs my tuner had his hands on (there are some pretty significant differences between the 08-09 and the 09.5 GTs). I also had a shit CAI that had an almost 90 degree turn right before the MAF (due to the positioning of the filter in the lower driver's side bumper/wheel well). This caused some pretty bad turbulence when the air hit the MAF and the ECU compensated by dumping a ton of fuel during launches and, essentially, drowning the motor as seen on my data log during a later run at a track. I published this video on June 21, 2014. I likely obtained the footage in early June.......in Florida. The weather at that time was certainly not ideal for putting down my best numbers. I'm not sure what area you live in, but I regularly see DAs in the positive thousands (+1800 to + 2200) where I live. Under these types of conditions, I've seen 10 second cars post times in the 12s. I've since corrected a lot of the issues mentioned, but I have not (vaguely) measured my 0-60 times again. I have run my car at a track, though, and have posted a personal best time of 12.711 @ 109.56 mph. Hope this clears some things up.

[@breqq]

Your g8 looks just like my g8 lol.

[@MRODRIGUEZ512]

Is that pinging at wot, or is it normal?

[@LEO8er]

Michael Rodriguez I think the decibels at the top end of the rpm range was too much for my mic to handle.

[@jujuhernandez8180]

Your in normal driving mode when your driving sir hit that sports mode

[@Aerohead]

You know you can just calculate the change in RPM using the gear ratios, right? StockRPM*(GR_New/GR_Old) for 55 mph: 1400*(3.45/2.92) = 1654

[@LEO8er]

Adam Weaver Cool!!! Thanks

[@saulmendoza4948]

Do you know if a 2013 Camaro SS 3.45 differential would work the same?

[@LEO8er]

I believe it will.

[@saulmendoza4948]

+LEO8er would I hate to swap suspension as well or differential only?

[@LEO8er]

+Saul Mendoza I would recommend replacing your differential bushings and rear cradle bushings at the same time. Doing so will save you time/money in the future. You are not required to replace anything else, but I would highly recommend you get your transmission tune adjusted.

[@LEO8er]

+Saul Mendoza I would recommend replacing your differential bushings and rear cradle bushings at the same time. Doing so will save you time/money in the future. You are not required to replace anything else, but I would highly recommend you get your transmission tune adjusted.

[@LEO8er]

I would recommend replacing your differential bushings and rear cradle bushings at the same time. Doing so will save you time/money in the future. You are not required to replace anything else, but I would highly recommend you get your transmission tune adjusted.

[@BornToBeFamed]

I think a 370 gear would perfect.