15 ratios changed

[Blue T/A 2.0]

I read something late last night about the 15 TA having different 5th and 6th gear transmission ratios than the other Vipers. Any truth to that? My Gen 4 had a real tall 6th gear that was unusuable under 80 mph and I hope they did not go back anywhere near that on the 15.

[Blue T/A 2.0]

Never mind. I looked it back up. The 15 GT and GTS models have a higher 6th gear for better mileage and less noise at highway speeds. It appears that the TA is unchanged as far as I can tell.

[Ryanr206]

If this is the case would putting a taller rear gear in now make more sense?

[Nine Ball]

If this is the case would putting a taller rear gear in now make more sense?

Depends on the purpose. By taller, I think you mean shorter? Moving numerically up to a 3.73 or 4.10?

Drag racing? Yes. It would make the car easier to launch from a stop.

Road racing? No. I don't see any benefit there. The car can do around 140 at the top of 4th, which is good for most tracks as-is. It would suck to have to grab 5th all the time.

[mblgjr]

It really just sucks they changed it back to being a useless overdrive

[Nine Ball]

It really just sucks they changed it back to being a useless overdrive

It is just on the GT and GTS models, the "highway cruisers". It won't suck actually, the car still has the 3.55 rear gear. I'd rather have that lower 6th OD gear, the current cars are at high rpm when we cruise around 80 mph.

[ViperGeorge]

It really just sucks they changed it back to being a useless overdrive

Disagree. Out west where the roads are long and the speed limits high a lower revving 6th gear is a plus. Cruising at 85-95 or higher in my 14 GTS with the Gen 5 6th gear gets old real quick. Too much noise and it sucks gas like there's no tomorrow. My Gen 4s are great to drive on the long runs our club makes. With the Gen 5 we're always looking for the next gas station.

[Junkie]

I wish my car had the different 6th and closer 5th. Who does 6th gear pulls?!?! 5th goes to 210+

[mblgjr]

Im over here in the Southeast; so we hit hills/mountains running interstate speeds; so its nice not to have to drop to 5th.

Ive been in vettes and g3 cars with the .50 6th; just personally despise it. ;)

I understand being out west/flat Texas and having a use for it.

[ViperGeorge]

Im over here in the Southeast; so we hit hills/mountains running interstate speeds; so its nice not to have to drop to 5th.

Ive been in vettes and g3 cars with the .50 6th; just personally despise it. ;)

I understand being out west/flat Texas and having a use for it.

Personally I'd rather downshift occasionally if I can run lower revs the rest of the time. Plus it saves gas and wear and tear on the engine. I also wonder whether it will reduce the gas guzzler tax.

[mblgjr]

I also wonder whether it will reduce the gas guzzler tax.

fractionally maybe. But not all

[Steve M]

fractionally maybe. But not all

I'd guess the same thing since not all '15 Vipers will have the revised 6th gear...then again, I'm not sure how the gas guzzler tax is imposed.

[Voice of Reason]

I don't think prior gen owners fully appreciate what cruising at 80-85 in a Gen V is like. Cruising rpms are just too high. You hear us talk about wanting a 0.5 6th gear ratio and your frame of reference is your 3.07 rear end. The 3.55 doesn't need the 0.63 6th gear, a 0.5 will get around just fine and still not bog down.

[mblgjr]

Prior gen engines weren't quite as happy to rev as the G5 engine really.

G5 GTS here; but I dont really cruise above 80 very often and ny sweet spot for long term cruising has been 75/76 for the most part.

Everyone has their preference. Glad the TA maintains the gearing.

[viper_eddie]

If you're cruising at 80-90 MPH in 6th gear in a Gen V, what rpms do you get? My Gen IV gets about 1500-1700 at those speeds. Trying to understand how big of a difference it is.

[Voice of Reason]

80-90 mph is roughly 2200-2500 rpm based on calculators I found online using tire height, gear ratio, and final drive.

[ViperGeorge]

80-90 mph is roughly 2200-2500 rpm based on calculators I found online using tire height, gear ratio, and final drive.

You are exactly right at 80MPH the Gen 5 is turning around 900 more RPMs. That's a lot. As stated its not just the 6th gear in the tranny, the rear end ratios in the Gen 5 are numerically higher than the Gen 4.

[J TNT]

Gen3/4 .50 6th gear with 3.55 is great. Imo

[swexlin]

It really just sucks they changed it back to being a useless overdrive

This, I love 6th in my Gen 5, over my Gen 3. It is now usable on my normal roads around where I live. Only time I will miss it is out to Carlisle on the PA Turnpike - where I got 23 mpg at 70 in the Gen 3.

Much better ratios in the Gen 5, combined with the 3:55 rear.

[Zybane]

Oh that sucks, so my TA2.0 will have the old 6th gear with high RPM cruising? You don't use the 6th gear on a road track, why wouldn't they put the newer 6th gear ratio in the TA to get the 20MPG? Any references to the TA confirmed having the old 6th gear?

[mblgjr]

Per an old thread around here the TA/TA2.0 maintains the "race car gearing" in the trans.

I believe Ralph had stated the G5 would achieve 200 in 6th originally; vs. 5th.

In 4500mi and multiple 12hr freeway stints; I've gotten 18-20 consistently. It's not like we're getting bad mpg now.

[theviper]

I think I already know the answer to this, but any way to change the gear ratios in the 2013/2014's?

[mblgjr]

I think I already know the answer to this, but any way to change the gear ratios in the 2013/2014's?

yes you can change the 5/6 in the trans but its kinda $$

Rear diff gears are no problem as normal.

[Jack B]

I do not believe there are ANY trans gears available at this point in time.



yes you can change the 5/6 in the trans but its kinda $$

Rear diff gears are no problem as normal.

[EZ 2B Green]

I think I already know the answer to this, but any way to change the gear ratios in the 2013/2014's?

I had my 5th/6th on a Gen IV changed a few years ago and I didn't find it too expensive. I think it was around $1300. Shipping the transmission (to/from) ~$300, Gears ~$500 Carbon fiber syncros ~$100 and the rest labor/gear oil. The process is pretty much the same on a Gen V. I would do it again without hesitation.

Final Drive on a stock Gen IV is 1.535. This is a little too tall for normal use. With the 0.63 6th, the final drive is 1.9341. This is much more useable and it gets me 20.5 MPG fully loaded (2 people and full trunk) on long runs with the top down. A Gen V with a 0.5 6th, gives you a final drive of 1.775 which is right in between the two final drives above. This would be my preference for a Gen V and it would bump it up over the 20 MPG threshold on the highway.

BTW: the MPG numbers quoted are with E10 fuel. I can feel the power difference and the car gets significantly better MPGs with 100% gasoline.

[Bruce H.]

The car can do around 140 at the top of 4th, which is good for most tracks as-is. It would suck to have to grab 5th all the time.

Maybe smaller tracks, but you'll be well above 140 mph and grabbing 5th on all the major tracks I've driven including Road America, Mid-Ohio, Watkin's Glen, VIR, Mosport, Mont Tremblant and Road Atlanta. Not sure what you've got down there but I only know 2 tracks within a days drive up here that I wouldn't need 5th on, and one is Ralph's personal go-cart track around his yard :)

[SilveRT8]

Getting over 140 at Mont Tremblant is seriously Hauling Ass !
Way to go !

[Bruce H.]

Getting over 140 at Mont Tremblant is seriously Hauling Ass !
Way to go !

Yeah, it feels rather quick as well! When I come on to the straight I just get over to the right quickly so I can crest the left kink with the car pointed straight and foot to the floor. Soon after you need 5th or coast before throwing out the anchor for the tight right at the end.

[SilveRT8]

Yeah, it feels rather quick as well! When I come on to the straight I just get over to the right quickly so I can crest the left kink with the car pointed straight and foot to the floor. Soon after you need 5th or coast before throwing out the anchor for the tight right at the end.

Thanks for the tip, I realize when I come to the straight that I'm letting the car go to the left towards the flagman a bit too much, making a long bend before the hill. I'll try your way next spring.