Changing rear end gears. Does it really WORK

[Toronto_ACR]

can someone please tell me whether changing rear end gears to lets say a 3.54 ratio, will actually improve quarter mile times. I want to see time slips of before and after if available.

 

[Craig 201 MPH]

From what I've heard and read, changing to a 3:54 will force you to change gears right before the end of the quarter, so there is no real difference in times, plus it will be a little more tricky to launch as the car is geared higher. You will lose some top end (for those late nights on the 407 E.T.R.) and gas milage will suffer (who cares) but (no pun intended) your seat of the pants feel is likely to increase for everyday driving.

I have no personal experiences (only driven on 3:07's) just what I've read.
Craig

 

[JonB]

Craig is right. Launch can be learned, but If 1/4 mile STRIP is your ONLY motive, then a hard-2-find 3.45 gear will not require the shift...unless you start running low-11s.

But if street / track performance is the goal, with SOTP "Push-Yur-Fanny-Back" noticable gains, then choose 3.55. (3.73 has too many cons) Personally, after hoses/filters, I think a ring/pinion swap is the #1 bang-4-buck Viper upgrade. For under $1000 out the door and down the road, you FEEL like you achieved a 15% HP gain "pulling power" !

5th becomes your friend....and hiway cruising in 6th can even get BETTER mileage vs cruising in OE 5th.

 

[PhilC]

JonB, are you guys saying that with the 3.55 you have to hit 5th by the 1/4 mile mark?

 

[Toronto_ACR]

Thanks for the input guys. But Jon can you answer me whether you have some numbers to prove the gain in quartermile if I went to a 3.55 gear. I imagine that the main reason the Porshes are so quick from 0-60 is not just the 4 wheel drive but the higher gear ratios that they have in first and second

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by JonB - PartsRack:
Craig is right. Launch can be learned, but If 1/4 mile STRIP is your ONLY motive, then a hard-2-find 3.45 gear will not require the shift...unless you start running low-11s.

But if street / track performance is the goal, with SOTP "Push-Yur-Fanny-Back" noticable gains, then choose 3.55. (3.73 has too many cons) Personally, after hoses/filters, I think a ring/pinion swap is the #1 bang-4-buck Viper upgrade. For under $1000 out the door and down the road, you FEEL like you achieved a 15% HP gain "pulling power" !

5th becomes your friend....and hiway cruising in 6th can even get BETTER mileage vs cruising in OE 5th.

<HR></BLOCKQUOTE>

 

[SteveBCloud9]

Ah... The proof... Yes......

 

[JonB]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Toronto_ACR:
Thanks for the input guys. But Jon can you answer me whether you have some numbers to prove the gain in quartermile if I went to a 3.55 gear. I imagine that the main reason the Porshes are so quick from 0-60 is not just the 4 wheel drive but the higher gear ratios that they have in first and second. <HR></BLOCKQUOTE>

a) I am agreeing with Craig, and most anecdotal evidence I have seen over and over for years; And from being tech inspector at ViperNationals I : a 3.55 does NOT end up completing the 1/4 mile significantly faster than an OEM for the hookup and extra shift FACTS cited above. (3.55 hits 4th before 1/4 mi.) Once you learn to hook, the times will fall.

b) On the street, or roadcourse, the 3.55 acceleration is about 15% faster, say from 20mph - 140 mph, than an OE 3.07. FACT

c) The P-911TT is faster in 1/4 mi for reasons of AWD (affects 0-60 segment drastically) and HP/WT ratio onward. Period.

Doubters like steveb (?) expect me to copy, file, and produce timeslips? Believe me. (Or not, sometimes at your peril.) The proof is on the roadcourse times, and the SOTP feel: #1 BANG 4 BUCK UPGRADE.

 

[TOOOFST]

Spend the money on HP mods for motor/exhaust,aesthetics first.Unless you can dead hook yearly.Better chance of seeing 11sec. with stock gear.In cooler weather the 345+ becomes more dangerous also.

 

[pauls]

Gear change is the best seat of pants increase, value for the dollar and ease of install you can do to your car. PS get a second rear and set up the new gear, keep your stock rear stock for a future reinstall or return to original. Oh, by the way I happen to have a complete extra rear for sale! Only $750

PS. I've never come close to needing to shift into 5th gear in the quarter with a 3.55 gear?

 

[PhilC]

I have to hit 4th by the end of 1/4 with my 3.07 anyway. That's why I questioned the "extra" shift. I couldn't imagine the need to shift to 5th with the 3.55

 

[onerareviper]

Viperholics,

I MUST chime in on this one. Changing gear ratios is one of the biggest 'bang-for'buck' mods that can be done. Unless your going over 124+ in the 1/4 mile, you DO NOT have to shift to 5'th gear in the Viper with 3.73 gears. 3.54 gears will reach 131+ in 4'th. PLEASE go to the link I have included for the 'FACTS ONLY'. And yes, a swap will make you car faster to 60 and 1/4 (if car does not exceed 4'th gear speed limit). Although, you have to learn how to make it hook (low RPM launch or modulating/riding the clutch). Here's the link:

http://www.viperclub.org/faq/techgears.html

P.S. - Car's with 650+ H.P. need not apply (Tom - BTR)...

 

[onerareviper]

Dan B.,

Correct. At least, that's what I've heard. And with that much H.P./Torque (you should know with 617 RWHP - Wow!!), they say it would be impossible to hook up. Is that true? Give us some details, as you 'Have the Power'. Have you consider a gear swap? I assume no, since you probably have a hard time hooking up as it is..... very curious.

 

[Toronto_ACR]

Thanks for the input guys. But I want to see time slips of before and after. Is there anyone that has timeslips with both the stock gear and then the upgraded gears. I have not been to the track yet so can someone tell me what is the gear you cross the finish line with and what rpm with bothe the stock gears and the upgraded gears.

thanks

 

[onerareviper]

Toronto_ACR,

Did the previous link answer some of your questions? Here is another excellent link that gives, 'Just The Facts'.

Later,

http://www.socalviper.org/techtips/gears.html

 

[Toronto_ACR]

Thanks I appreciate the link to the site explaining everything on gears. It has enlightened and educated me on gears.