Viper tranny owners, what gear are you using?

[stangbear427]

Who said anything about trapping out at 95mph and only using 2 gears. I was simply trying to make you see how soft that gearing senerio is.

...and to use your little set up.. viper + 2.73's in second gear would do 95 mph at 6040rpms and 55 mph at 3500 rpms.. I can only wonder what you'd use the last 3-4 gears for?

OK, everything looks the same as it did when I quoted it this morning, except the "3-4 gears". I said what did in response to "what you'd use the last 4 gears for?" I must have somehow missed the 3 while I was rushing this morning, at least now you know what I was thinking when I posted it. My friends LT1 is useless in 6th gear, just as much as the 5th in a stock stang with a T5. That car barely has highway torque in 5th, it never needed a T56- except perhaps in GM's looking ahead assuming we would change the rear gears anyway.

If your trying to prove "I was wrong" then perhaps i was. I've already admitted it's "my guess", "IMO" and so forth. Fact is you can run all the #'s you want. things will vary on clutch set ups, hp ratings, Hp of the car, how close the HP is to capablities of the clutch and drive train, Condition of the clutch set up, amount of stick on the track, and so on.. but bottom line if you run the numbers a 2nd gear start is not needed neither on the street nor on the track. and a Dodge Viper is a dog with stock gearing as would be a Mustang with 2:73/3:08's and a viper tranny..

OK, agreed. I wouldn't say I was trying to prove you wrong, per say. The only reason I went into the discussion at all was in response to your first response to me:

with my car and the power i had there is no way you could launch in 2nd gear with 3.73's

Now, "launch" was a bad word for me to use, because taking off like grandma is seldom reffered to as a launch. However, what I was addressing was the concern of forced87GT that 1st gear with 4.10's would be too short- which was an observation of my own everytime I drove or rode in a stang with 4.10's (note: none of them had a T56), 1st gear was useless. Taking off in 2nd was far easier, smoother, and didn't exhibit any problems. Maybe with the pathetic stock HP under the hood (although my wife's bone stocker takes of in second with ease), but never on an even mildly modified engine. I have no trouble taking off in 2nd, or even 3rd in my GT with 3.73's. Now, while it isn't remotely ideal, I have also launched in 2nd on the clock, and by only launching 2000 rpm's higher than in 1st was able to run within half a second of the times set launching in first. My TKO may have a lower 2nd gear ratio than a Viper T56, but not so much that another 140HP wouldn't more than make up for it. If it falls on it's face, the clutch isn't up to it or the R's are too low. But I wasn't meaning track talk, just daily drivability concerns about a 1st gear that's too short. If it isn't too short after all, fantastic. Of all of us, you would know. You've opened up something else even more disturbing now though- how could anyone consider a car that in 1992 would do 0-60 in four and a half seconds and run the quarter high 12's at 113mph in stock trim to be a dog? The slowest year I know of for the GTS was '96, and they were going 0-60 in 4.1 and the quarter in 12.4 @118mph on factory rubber- I can only wonder what that car would've done with slicks. If you think this car is a dog, I would love to ride in yours sometime... you aren't very easily impressed.

 

[gp001]

The chart I printed is from a program I wrote when I was deciding which tranny and which tranny gearset to use in my car. I found it easier to print up the charts of different trannys, tranny gear sets, and rear end ratios to see what I wanted to do. If you are interested the formulas are

mph = (rpm x tire diam) / (tranny gear ratio x rear ratio x 336)

Ex. mph in 3rd gear (Viper T-56) using a 245/45-17 and 4.10 rear gear
mph = (3500 x 25.6811) / (1.3 x 4.10 x 336)
mph = 50.19

RPM = (mph x tranny gear ratio x rear ratio x 336) / tire diam

 

[ponyboy19]

Now, while it isn't remotely ideal, I have also launched in 2nd on the clock, and by only launching 2000 rpm's higher than in 1st was able to run within half a second of the times set launching in first. :

.5 seconds in the quarter mile is a ton.. all you will see with a .5 second difference will be someones rear bumper in front of you.

My TKO may have a lower 2nd gear ratio than a Viper T56, but not so much that another 140HP wouldn't more than make up for it. If it falls on it's face, the clutch isn't up to it or the R's are too low. :

With a t5 and 3.73's with the 1.99 second gear and 461 rwhp I could set a blaze of smoke from the tires for a good distance but when the tires grabbed it would obviously lower the rpms down then work through the power band.. but with that senerio by the time they hooked the car was moving pretty good and would stay a bit higher in the rpms. Make no mistake about it she'd be very fast but not ideal. Had I put slicks on the car the rpms would have dropped right off the bat and the car would not have the forward motion like on a street tire burn out. My guess is it would have dropped below ideal power making rpms. Hence the reason why you lost .5 seconds when you did this at the track.. You have to remember with a centerfugal blower, boost and hp is dirrectly linked to rpms. the more rpms the more boost ='s more power, and you really need 35-4000 rpms to start cranking out boost and you want to keep it in that range when you shift to the next gear. so even on my 540 fwhp mustang if you were to launch in second and IF it fell on it's face it would have to work back through the rpms and started building boost again. you simply don't make huge power under 3000 with these blowers regardless of your peak power #'s. for example my car at 3000 rpms was only making about 200 rwhp compared to it's peak #'s. It's not like you have 550 hp at every rpm level and it can motor it's way through anything. you have to be in a certain rpms range and if you launch it in 2nd and the rpms drop to low then so does boost, as well as horsepower. That's why i say it wouldn't surprise me if it hooked it would bog with slicks and second gear.

But I agree you could start out in 2nd on the street with little trouble but like I already pointed out it's not nessesary to do so. viper, 2.66 x 4.10 = 10.906 vs t5 3.35 x 3.55 = 11.8925. So the viper with 4.10's will still give you a longer 1st then a t5 with 3.55 gears

My guess is even a viper with 450 hp and 3.08's launching on slicks in 1st will have a decent drop in rpms, difference is they have a ton of displacement, and more displacement means low end torque, and they make their power N/A which is much different then a little 302 with a centifugal blower making the same power or even more but relying on rpms and boost to do so. I think you may be over anticipating what 500+ hp really feels and acts like when made by a small displacement small block and a centerfugal blower and forgetting where the power band is on these setups.

how could anyone consider a car that in 1992 would do 0-60 in four and a half seconds and run the quarter high 12's at 113mph in stock trim to be a dog? The slowest year I know of for the GTS was '96, and they were going 0-60 in 4.1 and the quarter in 12.4 @118mph on factory rubber- I can only wonder what that car would've done with slicks. If you think this car is a dog, I would love to ride in yours sometime... you aren't very easily impressed.

I'll trust your #'s are correct as i'm not gong to take the time to verify them, but yes I wasn't overly impressed with the seat of the pants feel of the 450 hp V10 viper I was riding in.. was it a nice car, heck yeah, was it quick, you bet, but all i could think of is I expected more seat of the pants feel when the driver matted the gas in, I believe 2nd or 3rd. must have been second because it was taken to about 57-6000 rpms if i was seeing and remembering correctly. All i could think is "damn this thing would be sweet with a set of gears. there is a lot of untapped performance left to be had from a stock viper and all it would take is a nice set of gears.

that's my way of thinking and my opinion.. if you still disagree then let's agree to disagree and let this thing die as we pretty much destroyed the true identity of this thread with all of this. For that forced87GT I apologize.

 

[stangbear427]

.5 seconds in the quarter mile is a ton.. all you will see with a .5 second difference will be someones rear bumper a good distance in front of you.

...Hence the reason why you lost .5 seconds when you did this at the track.. You have to remember with a centerfugal blower, boost and hp is dirrectly linked to rpms.
...the more rpms the more boost ='s more power, and you really need 35-4000 rpms to start cranking out boost and you want to keep it in that range when you shift to the next gear. so even on my 540 fwhp mustang if you were to launch in second and IF it fell on it's face it would have to work back through the rpms and started building boost again. you simply don't make huge power under 3000 with these blowers regardless of your peak power #'s.


that's my way of thinking and my opinion.. if you still disagree then let's agree to disagree and let this thing die as we pretty much destroyed the true identity of this thread with all of this. For that forced87GT I apologize.

OK, first of all, I didn't do it at the track- because numbers run at the track mean very little to me. I bracket race in what we at the shop call the UDSD class. Unsanctioned Daily Street Duty. Anything I have run I've run with a G-Tech, which is unforgiving and pessimistic at best. When someone pulls their times out of the glove box, I'd rather they just leave them there- lets just run 'em and see who's fastest in the real world. The only time I care about the quarter is when the next stoplight is exactly 1320' away. Beyond that, the numbers are usefull in discussions like this, but pretty meaninless in my streetcar. Aside from my torque arm and drag spec LCA's, my GT isn't really even set up for it- it's hung, sprung and crossweighted for corners. Going deeper into your post, I see some of the apples and oranges we were trying to reconcile: I run naturally aspirated- and while my intake and cam don't start pulling real hard until 2500-3000 either- it's not the same as fighting to maintain boost. In this, I understand where you're coming from. I guess I was assuming that a 408 would have more low end grunt without boost than you claim to have- but I suppose that depends on the rest of your combo.
We may have gotten sidetracked, but I think there is a lot of usefull information here regarding driving with these transmissions and gear ratios which is what this thread is about. As of right now, it has 431 views and only 42 posts. I think it's more interesting then you give us credit for. If forced87GT is pissed, sorry dude. Hope you found out what you wanted to know- I think you did over 30 posts ago, and your thread lives on. Let us know how you like the 4.10's!

 

[forced87GT]

We may have gotten sidetracked, but I think there is a lot of usefull information here regarding driving with these transmissions and gear ratios which is what this thread is about. As of right now, it has 431 views and only 42 posts. I think it's more interesting then you give us credit for. If forced87GT is pissed, sorry dude. Hope you found out what you wanted to know- I think you did over 30 posts ago, and your thread lives on. Let us know how you like the 4.10's!

Never ever pissed!
I learned a great deal from you guys. Thats why I asked this question and others.
Don't be sorry for anything.
I come here every day to read what everyone has to say about different topic's. Some people who post don't even get an answer. Sooo ---
thanks to all who took the time to read and give their opinion's.
I for one, greatly appreciate them all.
Thanks

 

[ponyboy19]

I understand where you're coming from. I guess I was assuming that a 408 would have more low end grunt without boost than you claim to have- but I suppose that depends on the rest of your combo.

A 408 probably will have more low end grunt then I claim to have, but that's because all my experiences and claims with the Viper T56 is behind a modded and supercharged 302, not a 408. my combo that will consist of a 408 is still in the works and not yet completed.

 

[stangbear427]

A 408 probably will have more low end grunt then I claim to have, but that's because all my experiences and claims with the Viper T56 is behind a modded and supercharged 302, not a 408. my combo that will consist of a 408 is still in the works and not yet completed.

...the fog is lifting... For some reason I was under the impression the 408 was the one you had problems with, and you were getting it redone by Bennet or something. Sheesh. I've spent more of this thread out in left field... now everything you have been saying about your experience sounds right. I can agree to disagree, sometimes it seems like that's pretty much all I do in here but it isn't my intention. I just love this stuff, I live for it. I don't want to sound condescending or contrary, I'll just talk about this stuff all day to anyone who doesn't walk away. I was like that in highschool over a decade ago, and all that's changed since then is how much I've done with my performance infatuation. I agree with more of what you've said than you probably think. Thanks for not just putting me on your ignore list and dropping it. I think.

forced87GT Ditto. Good luck!

 

[ponyboy19]

: I agree with more of what you've said than you probably think. Thanks for not just putting me on your ignore list and dropping it. I think. :

You were close.. but i didn't have anything better to do