how do u know if u have 3.55's??

[MAVPR]

Hi all, I don’t think that I have 3.55 gears but then if the previous owner put them in and did not tell the dealer he sold too, then perhaps i do :s
In 4th gear at 70 mph my car is at 3000 rpm. Does anyone know if that is the correct rpm with or without 3.55's?

Thanks for any help

 

[MikeR]

Thats probably about right for normal gearing. I dont pay much attention. But sounds right, cause then if you shifted to 5th rpms drop and then into 6th at that speed your at around 1800 rpms. I usually STAY IN FOURTH ON FREEWAYS AT THAT SPEED AS WELL.

Edit-- I just noticed I was in wrong forum, though gearing is gearing, not sure how much difference your car is if any from a Gen 3.

 

[Craig 201 MPH]

what is redline in 1st gear? Stock gearing allows for about 57mph in 1st.

 

[Vypr Phil]

Hi all, I don’t think that I have 3.55 gears but then if the previous owner put them in and did not tell the dealer he sold too, then perhaps i do :s
In 4th gear at 70 mph my car is at 3000 rpm. Does anyone know if that is the correct rpm with or without 3.55's?

Thanks for any help

3000 rpm, stock rear axle ratio: 78.0 mph
3000 rpm, 3,55 rear axle ratio: 67.5 mph

Hope this helps!

Vypr Phil

 

[Steve 00RT/10]

My little chart shows 70 MPH in 4th / 3000 RPM would be 3:33 gears
3:07s would 75.58 MPH......3:45s would be 67.5......3:55s would be 65.4

3:33s are a good gear set.....hard to find those gears

Steve

 

[CROM]

what is redline in 1st gear? Stock gearing allows for about 57mph in 1st.

What Craig said.

 

[Vypr Phil]

3000 rpm, stock rear axle ratio: 78.0 mph
3000 rpm, 3,55 rear axle ratio: 67.5 mph

Hope this helps!

Vypr Phil

My little chart shows 70 MPH in 4th / 3000 RPM would be 3:33 gears
3:07s would 75.58 MPH......3:45s would be 67.5......3:55s would be 65.4

3:33s are a good gear set.....hard to find those gears

Steve

MAVPR,

Steve may well be right. I gave you numbers for an SRT-10, but you seem to have 18" rear wheels so the numbers would be slightly lower than the ones I gave you.

And yes, 3.33's are a great choice and indeed hard to find, I second that!

Happy Vipering

 

[Paul Hawker]

Who ever installed the gears will place a small metal tag, stamped with the gear ratio attached to your rear pumpkin. Should be easy to find with a flashlight.

 

[2000_Black_RT10]

There's always the old fashion method..

Jack the car up on stands so you can crawl under it.. Mark your drive shaft and mark a tire because what you want to do is count the number of revolutions of the tire and the driveshaft.

Put the trans in neutral (car is not running obviously..), have someone rotate the tire 1 complete revolution and count the number of times that the driveshaft rotated, i.e. 3.55 is just over 3 and 1/2 rotations vs. 3.07 would be just over 3 rotations of the driveshaft and 3.33 would be 3 and 1/3 rotations of the driveshaft.

 

[MAVPR]

Thanks for all the replies guys!
Steve, great info from your chart thank your, Interesting to think I might have 3.33's, Ill take better note of the exact speed the next time and check it against your post!

Next time im out ill also take it to the red line in 1st (never done that) and see what speed she is at. I see there is a yellow/orange line before you get to the red, I take it there is no problem going right through this up to the 6,100/200 red line? Sorry if that is a stupid question im still learning the car

I should also have said i have a 97 gts so i have 17 inch wheels.

Jonathan

 

[MAVPR]

Who ever installed the gears will place a small metal tag, stamped with the gear ratio attached to your rear pumpkin. Should be easy to find with a flashlight.

Ill also have a look for this.

Thanks

 

[Steve 00RT/10]

Thanks for all the replies guys!
Steve, great info from your chart thank your, Interesting to think I might have 3.33's, Ill take better note of the exact speed the next time and check it against your post!

Next time im out ill also take it to the red line in 1st (never done that) and see what speed she is at. I see there is a yellow/orange line before you get to the red, I take it there is no problem going right through this up to the 6,100/200 red line? Sorry if that is a stupid question im still learning the car

I should also have said i have a 97 gts so i have 17 inch wheels.

Jonathan

Your welcome. The other factor not mentioned, which would have a definite bearing on the MPH is the OD of your tire/wheel. To arrive at the numbers I got .. I used 26.1 inches for the measurement. I believe this equates to a 'stock' Michelin tire......even for the 97. The newer 18" wheels came with a lower profile tire than the 17s. You might want to measure your tire diameter to make sure. You could also work your way through the Tire Rack site to find the OD of your tire.I have a spread sheet made for the different combos by 1000 RPM increments. 2:92 (19" wheel package on a 3:07 rear end--27.4" tire OD), 3:33s, 3:45s, and 3:55s. I'd be happy to send the sheet to you. There are any number of gear calculator sites you can get to. They will all ask for the tire OD in order to do the calculation.

There is no good reason to go to redline in first to see the speed. Go to 3100 and let it stabilize there.......then double your speed to get what 6200 would be. Plenty close enough and you don't have to pound the engine.

Steve

 

[MAVPR]

Steve, that would be great if you dont mind sending me your spread sheet.

"There is no good reason to go to redline in first to see the speed. Go to 3100 and let it stabilize there.......then double your speed to get what 6200 would be. Plenty close enough and you don't have to pound the engine."

This sounds like something i feel more comfortable with!

Thanks again!

 

[2000_Black_RT10]

You guys had me intrigued to verify what's in my diff, here's what I suggested in the previous reply with pics. I have 3.07..

It took me 5 minutes by myself, block the front tires, lift the car up in the rear and use a safety stand. Put the trans in neutral, release the parking brake. Crawl underneath the car, mark the tire, yoke flange, and diff housing and reach over while under the car and rotate the tire, it rotates quite easily.

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[ruckdr]

The tire/drive shaft rotation is a good way to go. Now if you want to see what different rear end ratios, tire diameters, and transmission gears ratios do relative to MPH and or RPM, use this Gear Calculator:
http://www.xse.com/leres/bin/gearra...re=diameter&diameter=25.6&circumference=81.40

Viper stock gear ratios:
1st 2.66
2nd 1.78
3rd 1.30
4th 1.00
5th 0.74
6th 0.50

Reverse 2.90 (Oh, at 6000 RPM you can go 50+ MPH in reverse.... Good Luck)


Later,

 

[MAVPR]

Wow great response from everyone! And a few different options for working it out.

"2000 black rt10" thank you for going to the trouble of taking those pics, now that i can see what you were talking about with my own eyes I will have no problem giving that a try.
Ill be sure to post what i find out.


Jonathan

 

[Steve 00RT/10]

Did you the spreadsheet come through? Sometimes attachments get blocked.

Steve

 

[MAVPR]

Yep got it

Ill take the measurement for spread sheet then take speeds on my next outing.

Jonathan