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I have a 99 gt. i just bought the car so it is relatively stock. I have a pro 5.0 shifter and a bbk offroad x pipe. I want to get some new gears for the car, i dont want to go with the 3.73 gears. i have been looking at either the 3.90 or 4.10 gears. If anyone one has any advice on the subject it would be much appreciated....thanx
 

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I have the Motive 390's. I like them. I'm sure the 410's feel almost the same and are a lot cheaper price wise.

BTW, I'm in Las Cruces.
 

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I love my pro5.0 3.90's i decided to go with 3.90's because of the traction issues with the 4.10's if you can't hook up whats the point. I'm not saying that there is a big difference just that its hard enough with 390's, 410's would be even harder. It spins at a couple of hundred RPM's slower at highway speeds. Whatever ones you go with you will be happy, both of then give great off the line acceleration.
 

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i was in the same boat a short time ago.

i went with fms 4.10's, because...
1. they are fms.
2. for the 5% difference in rpms, I doubt'd that would be an issue.
3. they are fms.
4. I need'd all the help I could get in the 60' department.
5. they are fms.

a bigger gear does not make traction a problem.
a bigger gear spins the tires at a slower rate in comparison the the ground speed than a smaller gear, so, throttle manipulation allows more control of the spin/bog problem. Also, the bigger gear will allow the tire to recover more quickly from spin, than the smaller gear, agin, due to tire speed.

My FMS gears went in in just over an hour... fit like a glove... same shop installed a set of Motive's right after I left... over 3 hours to get them set up clean... $$$ Yikes!

I'm certain you'll be happy with either gear.
Good luck.
 

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I installed a set of 3:90 motives over the summer inplace of ford 3:55s and had no trouble at all seting them up. Fit and finish was second to none.
If I had to do it over I would get the 4:10s so I could get my rpms a little higher through the traps. I say that both makers are about the same for quality. Although I think the FMS are made in the USA . Motives are German forged and machined in Italy.
Go for the 4:10s from either one.
 

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I am seriously considering 3.90; however, I have a concern for a correct speedo gear. Does anyone make the correct speedo gear for 3.90's? I currently have a 23 tooth speedo gear for my 3.55's.
 
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