3.07 to 3.55 on the Street???

[2002_Viper_GTS_ACR]

I stopped reading eveyones responses, so if this is a repeat.. sorry.

Here is the deal, I was making 460hp and 500 tq (rear Wheel) when I felt there were no more bolt ons to be had. I picked up a 3.55 from the Cones (Janni and Henry) and had it installed. Up to that point, I had been running 11 sec passes in my 02 ACR with bolt ons (I was a drag *****). And I would go from a dig at street lights all the time against my buddies z06.

I can drive.. trust me, I can drive. When I went to the drag strip, I was pulling off the EXACT same times, no gain. This was at a well prepped track, so it wasnt traction limiting issues. Then the really bad part....

I couldnt beat my buddys z06 from a dig to 60 anymore. The 3.55s turned my car into a show boat.. I could spin tires like I was a drifter, but couldnt get them to plant.

So my opinion, leave the 3.07's and just build more hp, as hp is the answer to everything Not simulating it by gears.

Then if you just HAVE to do it, then realize to get the car BACK to where you can actually rocket out from a light, your going to need to run on Drag Radials, and at which point, I hope you dont like taking turns quickly.

Enjoy,

Jon

 

[Parisianviper]

2002 viper gts acr, how about a 3,55 and a Quaife?
will that solve the traction problem?

 

[Fred(DrivingSchool)Kinder]

Jon,

Good info! Good Driving!

To the rest of you:

Spend your money taking a performance driving school(Skip Barber) to learn car control and vehicle dynamics then practice drag racing or go play on road courses.

Knowing the limits of you car and driver will provide the best results.

We also have this idea that more hp will make us faster. Fact is that more hp makes a Viper more difficult to maximize performance. The first step in getting the most of of a Viper is knowing how to drive.

Everyone that owns a Viper thinks they know how to drive. To prove that wrong just take a look at the range of lap times at a Viper Days event. You will find that a good driver in a Neon will be faster than a owner without performance driving training, in a pumped up Viper!

 

[DEADEYE]

"Launch is difficult enough with stock gears, the 3:55's would seem to make it more difficult to launch?"

To get a good dragstrip launch. Something is going to have to slip.

There isn't enough horsepower availabe at low rpm to get the car moving quickly from a dead stop.

So the engine is run up to a higher rpm where more power is being produced and then the wheels spin or the clutch slips until the speed of the car equals the speed of the engine through the geartrain.

With a 3.55 that matching speed and rpm will happen sooner than with a 3.08

The driver is going to have to feed in the clutch and/or deal with some wheelspin,
but this will be needed with either rear ratio.
With the 3.55 you don't need to slip as long.

A 3.08 gives you less torque at the wheels from a dead stop.
If you think less torque is good.
Try starting from a dead stop in second gear.

A car with an automatic will have a high stall speed coverter in order to allow a higher engine speed before lockup. This is sort of the same as slipping the clutch in a manual transmission.

But then you come to the 1st upshift quicker and lose ground to the 3:07 car. You're now in second gear while his 1st pulls harder. So on and so on. Someone best described it as a seesaw race.

 

[joe117]

As you say Fred, skill is needed,
And if you know how to launch with a 3.55, you will get off the line faster than you will with 3.08

There is more torque at the rear wheels in first gear with the 3.55 than with the 3.08
You just have to know how to use it.

If you need x amount of torque at the rear wheels to get you the best start, you will get that torque at a lower engine rpm with a 3.55
Lower engine rpm will allow you to to be able to stop the slipping earlier.

As I said, in a drag race start, something is going to have to slip in order to get enough rpm to have the engine making the needed hp.
The tires should spin a little and the clutch should slip a little. A perfect mix of the two will give you the best starts.

Too much torque your problem? Would you have a better 60ft time if you pulled a plug wire?

I'm talking about acceleration from a dead stop.
If you need an extra shift in the 1/4 mile with the 3.55 then you will perhaps end up with the same ET.

As far as road racing, the right rear will be the one that puts you in the right gear in critical places on the track.

 

[GR8_ASP]

For the track you want the gear that jsut tops out in one gear at the finish. Say with a 3.07 you hit the finish line near the rev limiter in 3rd. Change to lower gears and you add an additonal shift as you will now need 4th. Any gain that you made earlier in the run is offset by that shift.

Now if you are already going into 4th lowering the gear will move your shift points earlier on the track and you should have an increase in the area under the hp curve. Thus you should improve.

Not sure if that is why some see a 1/4 mile improvement or not but that is my take on it. Ignoring the traction aspect as the right foot should be the controlling factor there in both cases.

 

[99 R/T 10]

I stopped reading eveyones responses, so if this is a repeat.. sorry.

Here is the deal, I was making 460hp and 500 tq (rear Wheel) when I felt there were no more bolt ons to be had. I picked up a 3.55 from the Cones (Janni and Henry) and had it installed. Up to that point, I had been running 11 sec passes in my 02 ACR with bolt ons (I was a drag *****). And I would go from a dig at street lights all the time against my buddies z06.

I can drive.. trust me, I can drive.

No, really, what is the reason you're so slow?

 

[OKViper]

I stopped reading eveyones responses, so if this is a repeat.. sorry.

Here is the deal, I was making 460hp and 500 tq (rear Wheel) when I felt there were no more bolt ons to be had. I picked up a 3.55 from the Cones (Janni and Henry) and had it installed. Up to that point, I had been running 11 sec passes in my 02 ACR with bolt ons (I was a drag *****). And I would go from a dig at street lights all the time against my buddies z06.

I can drive.. trust me, I can drive. When I went to the drag strip, I was pulling off the EXACT same times, no gain. This was at a well prepped track, so it wasnt traction limiting issues. Then the really bad part....

I couldnt beat my buddys z06 from a dig to 60 anymore. The 3.55s turned my car into a show boat.. I could spin tires like I was a drifter, but couldnt get them to plant.

So my opinion, leave the 3.07's and just build more hp, as hp is the answer to everything Not simulating it by gears.

Then if you just HAVE to do it, then realize to get the car BACK to where you can actually rocket out from a light, your going to need to run on Drag Radials, and at which point, I hope you dont like taking turns quickly.

Enjoy,

Jon

Jon,

As the original poster, this is EXACTLY what I wanted to know! I already knew that theoretically I would faster on the street from a dig, but with the power I have (and you have) I was worried about being able to use it. I saw other posters saying "learn to drive", but on a street the variables are sometimes too much to master every time.
I will stay with stock gears based on this post. Thank you.