View Full Version : Transmission Question

06-03-2005, 03:58 PM
I have a 1999 cobra and was thinking of changing out the ring and pinion gear to a 4:10. Since this would raise my rpm's at higher speeds my second thought was to swap my current 5-speed trans with a 6-speed from a newer cobra. Anyone know if they are interchangable or any comments on the ring and pinion?

06-03-2005, 06:27 PM
I would just do the gears and drive it... see how it is...
A six speed conversion is going to cost some money...

Although nice... I don't think you'll need it...

Jimmy :thumbsup:

06-03-2005, 06:42 PM
I remember you had told me about the 3:76 gears. I am in a debate about 3:76 and 4:10. If I go with 4:10, then the engine will be buzzing pretty good at 70mph. How will it be with the 3:76's?

06-03-2005, 07:41 PM
4.10 are great for the drag strip but tough on gas mileage.

4.10s with a 26" tire, at 70mph - you'll be running 2967 rpm :eek:

3.73s with a 26" tire, at 70mph - you're at 2699 rpm.

The 4.6 DOHC loves the higher rpms and comes to life above 3000 rpm, but at $2.50/gallon - hope your bank account is heavy duty

Most importantly - HAVE FUN :rotf:

06-04-2005, 12:19 AM
I guess 2900rpm is a bit hi for cruising :( Could the little 4.6 handle the high rpms? I suppose it hasn't quite set in how durable these engines are. As far as gas consumption, I only drive it on the weekends if it is not raining. So a total of 500 miles a month is put on it.

06-04-2005, 01:14 AM
Put 4.10's in mine a few months ago. Love 'em. Really wakes it up and makes it so much easier and nicer to drive around town.

They are a tad busy on the highway. Turns near 3 grand at 80 mph. Not so bad at 70.

Just ran from Boston to NJ and back over the long weekend. Those rpm's are little tiresome for a road trip, but if you don't drive long hauls then it's not a concern.

Normal driving is down one half mpg. I got 22 mpg to/from NJ going 75 the whole time. I never measured a highway trip before the gears.

Just go for it. 4.10's aren't too much.


06-04-2005, 11:17 AM
Thats me all over. I only drive it on the weekends around town. Only 2 times a year I drive to Austin for our "Hill Country Cruise".

06-04-2005, 11:21 AM
Just do it. Here's a great comparator: http://www.svtoa-atlanta.org/cgi-bin/trans.cgi


06-04-2005, 02:33 PM
I'm so glad someone who has done it chimed in... thanks RP...
After we had talked a while at the Joe Myers show... I was pretty sure the 4.10s would be a good fit for your application...
The six speed has a completely different gear set and as a result 410 + six speed is going to make the 1st 2 gears VERY LOW...

Keep in mind the benefits of reducing rotational weight... IE lightened ring and pinion, aluminum drive shaft, Wheel & tire combo...ETC..

Also if you are thinking the 4.10s might be too much(I don't)... there is also now availability of a lightened 3.90... also from www.motive.com


The Famous AX now comes in Ford 8.8"!
The 8.8" factory lightened performance enhancing gear set sheds up to 2 lbs. of rotating weight! This can mean the difference between 1st or 2nd place or qualifying or not. Just because it's lightened does not mean it's frail. This gear set gets a proprietary heat treatment that makes it super strong. Stronger and lighter means better performance.


I've also read that someone bought Ford Racing gears and when they opened them up.....THEY WERE THE LIGHTED ONES!!!

So perhaps the newer stock is coming through sourced from Motive???

Either way... 3.90 or 4.10 try to find a lightened set...

The feedback on a gear change for that car is nothing less than phenomenal!!!

Jimmy :thumbsup:

06-04-2005, 11:28 PM
I have 373's, but I travel the highway quite often. The peformance gains are impressive. I wonder sometimes how 410's would be but then again I travel the highway and am very happy with me choice of gears. I pull between 2250 to 2500 on the highway, I also went with the gear from steeda for the speed and it is off by 2mph. I would suggest a speed cal.