Motive 3.90's!!

Motive gears are good gears. Ford Racing are probably better, but I would not loose sleep over it.

There is very little difference between 3.90 and 4.10's. I understand why they have this ratio as there is so much discussion between 3.73s and 4.10s. I would say just drop in the 4.10's! But, you know what is best for you - it is your decision. I am not implying that it is a bad choice, you know your needs.

I mudled over this choice for weeks and finally went with 4.10's. Now I wish I had 4.30's.

Anytime you go to a gear ratio like this and DR, you increase the risk of breaking your rear end. No one can tell you for sure. It is simply an increased risk. If you plan of racing, be prepared to spend the $1000 or so to fix, but wait until it breaks. If you are worried, you may have to go a little easier than you would like on the launch.

Try the 3.90's first without the DR's, then decide if you need them.

man the diff between 3.90's and 4.10's is only 250rpm just get the 4.10's. Don't fear the gear!! Trust me you will love 4.10's.

droptopsnake01 said:

man the diff between 3.90's and 4.10's is only 250rpm just get the 4.10's. Don't fear the gear!! Trust me you will love 4.10's.

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actually less than 200 rpm @ 70 mph. I have 4.10's and if it wasn't my daily driver i would have put in 4.30's.
Also I only use FRPP gears, but that's my preferance, knowing that the 4.1 i put in my car is the same part that is used for over 100k miles on ford pickups proves they are a quality unit.

FEAR NO GEAR ! I've busted a few teeth of the ring gear of a set of FRPP 4.10's in my old 93 bracket car when I did my first launch on slicks(31spline spool I still don't think my buddy heat cycled them like I asked) and the gears still ran without any noise, hell I used them for a whole season. . .