Should I consider a smaller rear end? (ok, really, though)

[Chuck 98 RT/10]

Topic comes up every other month. This is a street car right? Then the bottom line is 1/4 times and as of yet nobody has confirmed a quicker time with a gear swap...Anybody? All they ever come up with is this SOTP "feel." Maybe there is something to it, but it hasn't been enough to sell me.

Road course is another story.

 

[Anthony - 98 GTS]

I believe the consensus is the below 600 rwhp - go for it - best SOTP performance for the money.

Above 600 rwhp - too much gear.

Just my $.02.

 

[Anthony - 98 GTS]

Rick,

SOTP = Seat of the Pants, ie. How fast the car feels.

 

[Chuck 98 RT/10]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Rick:
You'll have to pardon my ignorance, but what does SOTP stand for?
And one other thing: do I have to change the half-shafts if I change to the 3.55? Thanks again.

<HR></BLOCKQUOTE>

SOTP = seat of the pants. Also referred to as the ButtDyno although usually inversly controlled.

You only need to change the halfshafts if you're going to go with stickier tires. Slicks and possibly ET Streets depending on how hard you launch.

 

[tmcalist]

check out the "cost to change rear ratio" post - it gives some information on cost and the debate on what you will gain if you have this done. I agree with Chuck though, that it all seems to be about how things "feel", but not numbers on the impact on times with or without this swap done.

 

[KenH]

For the street, I don't think absolute 1/4 mile improvements are as important as 0-60 or 10-80 type sprint times. I find it hard to believe that lower gearing won't provide documented improvements in these types of sprints due to torque multiplication, especially if you are not adding an additional shift point to reach the same speed.

In the OLD days, everyone ran 4.10 or lower gearing to improve straight line acceleration performance. Why would the Viper by any different unless you were absolutely traction limited?

On a related note, does anyone know current 3.07 gear red-line speeds for each gear and how that is affected by lower gears such as 3.55? I only hear talk about whether you need to hit 4th in the 1/4 mile.

--- Ken

 

[ACR Joe]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Chuck 98 RT/10:
..... it hasn't been enough to sell me.
<HR></BLOCKQUOTE>

Chuck, I agree with you totally as I have on most every other issue. Just gave up my Tampa responsibility; would have been cool to meet in Ybor.

 

[onerareviper]

Do a search on gears and you will find all the info. you could ever want and need on gears.

Later

P.S. - The Viper is no different than any other car, and if traction can be achieved your 1/4 mile times will improve. 3.73 can achieve 124 MPH in 4'th, which most Viper owners can not exceed unless moderate mods are done. Stock cars generally finish the 1/4 mile in 4'th gear as well, therefore you are not doing anymore shifting with 3.73 vs. stock 3.07 unless you exceed 124 MPH. I think 3.55's can go to 131 or so in 4'th, but read the links in the other post for exact info.

 

[VIPORXXX]

Chuck, you made the comment "Road course is another story"

What do you mean???? Does the gear change improve lap times????
My Viper is pretty much stock but love to take it to the track for club events, Viper Days etc. and just tooling around town.


Thanks
Fast Eddie

 

[Chuck 98 RT/10]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by KenH:
For the street, I don't think absolute 1/4 mile improvements are as important as 0-60 or 10-80 type sprint times. I find it hard to believe that lower gearing won't provide documented improvements in these types of sprints due to torque multiplication, especially if you are not adding an additional shift point to reach the same speed.

<HR></BLOCKQUOTE>

The 1/4 is usually won in the first 60'. If a gear swap increases the 60' then it SHOULD show up in the ET. But I'm not married to this logic so if anyone can produce timeslips, feel free to jump right in.

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by KenH:

In the OLD days, everyone ran 4.10 or lower gearing to improve straight line acceleration performance. Why would the Viper by any different unless you were absolutely traction limited?
<HR></BLOCKQUOTE>

Contrary to what some believe the old muscle cars did not have near the power of our Vipers, plus they averaged several hundred pounds heavier. A 4.10 would be more beneficial in that case. Take a look at todays overweight and underpowered 'stangs. A gear swap is one of the first things on their list.

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by VIPORXXX:

Chuck, you made the comment "Road course is another story"
What do you mean????
<HR></BLOCKQUOTE>

If your running road slicks or Hoosiers and can get the power to the pavement then a gear swap might decrease lap times, as it might in the 1/4 with drag slicks. I don't think there would be a benefit with street tires though. Thankfully most ViperDays classes don't allow anything other than the stock gear.

ACR Joe, we'll meet up at VOI if I'm not broke by then. Can't agree with you on that V-rod though. Fugly.