View Full Version : 410 Vs 327

07-24-2002, 03:53 PM
hello everybody-
im in this debate over top end with 410 VS 327. Im I correct to assume that in a stock Cobra you indeed lose Top end with the 410 's Vs the 327 gear. But even though you lose Top End with the 410 you pull alot harder to redline. Meaning that with the 327's in theory your top speed is 150 vs 130 with the 410.

Is this some what correct?? I always assumed the lower the gear(373, 410 ect), the harder you pull, but you suffer in the top end MPH . Am I wrong?(im taking into account the added 200 rpm per step in gears)

Of course this changes with mods, but with all things equal, lets just consider just a stock Cobra.

somebody tell me im not crazy.


07-25-2002, 09:35 AM
You are not crazy. That is correct. A 4.10 will pull harder, but will not be able to reach as high of a "theoretical" top speed. However, change out the 5th gear in your tranny to a gear that actually does something besides overdrive, and a 4.10 would be a nice gear for the 4V motors.

For road racing, I'd still go with a 3.73 though...

07-27-2002, 07:16 PM
Yes, in a VACCUUM. the stock 3.27 gear will take a Cobra to a higher top speed than with 4.10's. If you use the RPM/Speed/Gear Ratio Calculator on the Corral (http://www.corral.net/tech/), you can see that the top speed with 3.27's @ 7000 RPM would be 244.1 MPH and with 4.10's would be "only" 194.7 MPH. However, since we can't drive on the moon :D we are of course limited by aerodynamic drag.

Assuming stock (or near-stock) power and stock diameter tires, a 3.27-geared Cobra is actually SLOWER on top end than a 4.10-geared car because it can't overcome the drag in 5th gear and hits an aerodynamic wall. Top speed is actually reached in 4th gear - and is supposedly somewhere around 150 MPH. With 4.10 gears, the car can pull 5th gear and is supposedly capable of around 160 MPH. It takes a long time to get there, but it is possible - according to first-hand reports I've read on other message boards. I have personally taken my car (4.10-geared near-stock-powered '96 Cobra) to 145 MPH in 5th - and it was still accelerating. I had to halt my little speed run IMMEDIATELY because my hood went *POP* when the stinkin' latch failed!!! Talk about getting on the brakes!!! *LOL* Thank goodness the secondary latch held or I would have lost my hood, windshied and probably trashed the roof. I haven't had any interest in taking my car that fast since then ;) I HIGHLY recommend hood pins for any high-speed runs.

I have no road race experience (just one open track event), but have also heard from others that 3.73's are the preferred gear for that in mod-motored Cobras.

BTW Brian, congrats on your racing successes so far!!! I'll be there pulling for you next weekend at CMP!

07-28-2002, 06:47 PM
Hey thanks John!! Looking forward to seeing you there!! I'm keeping my fingers crossed for cooler weather!!!!! LOL!!