2.73's to 3.73's
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2.73's to 3.73's
I plan on getting some 3.73's to replace my 2.73's. Just have a few questions that I couldn't find answers to in the stickys. I know I've got the 2 series carrier. On speed inc's website it says that the Richmond gears are thick gears to replace the 2.73's and the Motives just say they are for the 2 series carrier but also list a ring spacer for sale to use with the 2.73 carriers. Am I forced to go with the Richmonds if I want to avoid using a ring spacer or am I reading something wrong on the site, ie. does Motive also offer a thick gear.
I'm assuming the master install kit for both brands would include everything I need to do the swap. Part of the reason I'm switching gears is because I noticed the car has developed a rear pinon seal leak, so figured I might as well throw a gear in there while getting the leak fixed.
Last question for now, would I have to get the car tuned for the gear change? Does it just adjust the speedo or do the shift points also need adjusted? I'd get it done eventually, but the closest tuner is atleast an hour and 15 mins away, so I wouldn't be able to get it done right away. Just want to know that I'd be fine with doing the swap without the tune.
I know I'm a gear swap noob, but just couldn't fine much on the 2.73 to 3.73 other than people saying that its worth it.
I'm assuming the master install kit for both brands would include everything I need to do the swap. Part of the reason I'm switching gears is because I noticed the car has developed a rear pinon seal leak, so figured I might as well throw a gear in there while getting the leak fixed.
Last question for now, would I have to get the car tuned for the gear change? Does it just adjust the speedo or do the shift points also need adjusted? I'd get it done eventually, but the closest tuner is atleast an hour and 15 mins away, so I wouldn't be able to get it done right away. Just want to know that I'd be fine with doing the swap without the tune.
I know I'm a gear swap noob, but just couldn't fine much on the 2.73 to 3.73 other than people saying that its worth it.
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Summit shows a Motive 3.73 set for a 2 series carrier.Since it's a different P/N from their 3.73 for a 3 series carrier,you would not need a spacer.
Speedo should be reprogrammed.
Fixing a leaking pinion seal can be easily accomplished without having to go into the rearend.
Speedo should be reprogrammed.
Fixing a leaking pinion seal can be easily accomplished without having to go into the rearend.
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You will certainly want a thick gear. The spacer is used to make a series 3 gear fit in a series 2 carrier; avoid it like the plague. BTW, IIRC Strange also makes a thick 3.73 gear. I run their 3.42 in my series 2 carrier.
Both install kits will work; Ratech also makes one.
You will need a transmission tune in your PCM, which is fairly minor. The PCM will be confused about when/where to shift until you get one.
Both install kits will work; Ratech also makes one.
You will need a transmission tune in your PCM, which is fairly minor. The PCM will be confused about when/where to shift until you get one.
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I had my old tuner recalibrate the gears to 3.73's and he changed a few things in the tranny. I picked up .7 in the 1/4 going from 2.73's to 3.73's, but the temp was also 20 degrees cooler vs the last time I took it to the track. You'll love them. I went with the Motive 2 series, and I didn't buy the Master Install Kit. I did pick up a bottle of posi additive, but told it wasn't required but I bought it anyways, along with 75w90 Mobil 1 Gear oil. This was in my 98 TA btw.
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Ok thanks guys. The whole thick gear thing on their site had me confused. I think I'll go with the Motive 2 series and get the install kit as well. I'd be happy with picking up 2 or 3 tenths. I know my brothers 3.23 car just feels like it pulls harder with less mods, even though mine is 4 tenths quicker at the track.
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I have a 2 series carrier and went with Motive 3.42's from Jawsgear. They are a sponsor here and I got them within 3 days of the order along with the Masterkit. Give Jeff a call and he'll hook you up.
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Here's the same ones I bought...
http://store.summitracing.com/partde...5&autoview=sku
I paid about $10 less for it over a year ago, and a local speed shop special ordered it for me so no shipping cost.
http://store.summitracing.com/partde...5&autoview=sku
I paid about $10 less for it over a year ago, and a local speed shop special ordered it for me so no shipping cost.
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Well I got the MOT75373X with the install kit. That should be all I need to make the switch from 2.73's to 3.73's correct? Other than a tune of course. BTW, how much faster will I rack up the miles with the 3.73's on the stock gear tune? And is there much of a "break in" period for new gears?
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Well I got the MOT75373X with the install kit. That should be all I need to make the switch from 2.73's to 3.73's correct? Other than a tune of course. BTW, how much faster will I rack up the miles with the 3.73's on the stock gear tune? And is there much of a "break in" period for new gears?
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One can save a lot of money and energy just swapping in a 3.42 axle assembly from a stick car. More heavy lifting but less setup risk and cheaper.
For street use you'll be hard pressed to notice the difference between 3.42's and 3.73's. 3.42's will give you enough power to be traction limited.
Proper tune is critical regardless. It is not an option. Diablosport Predators can do a fine job with some custom tune support tweaking. I would not use a Hypertech.
Plan on losing 2-3mpg. Don't believe people who say it makes no difference. The loss of range per tank annoyed me more than the loss of mileage.
For street use you'll be hard pressed to notice the difference between 3.42's and 3.73's. 3.42's will give you enough power to be traction limited.
Proper tune is critical regardless. It is not an option. Diablosport Predators can do a fine job with some custom tune support tweaking. I would not use a Hypertech.
Plan on losing 2-3mpg. Don't believe people who say it makes no difference. The loss of range per tank annoyed me more than the loss of mileage.