Changing Gears

[Mother]

I also run M/T's. But I have 700 HP plus in a 460 BB. The torque kicks in at 680# at 1450 rpm. My finals are 3.55's. I have a TKO 600 close ratio. I have to be light footed on the loud peddle coming off idle. A gentle squeeze, and a shift into second and I quit. I know what my unit performs like. I have nothing to prove.

[mpanten]

Originally Posted by itstock

Greg Schroeder does it on a prepped track with ET STREETS. Have you tried driving around on aired up ET streets...on the street with no heat? They suck. There is NO traction with them. Heated and aired down, great. Otherwise, no. And don't even attempt any turning on them.

We are not saying the car will be "undriveable'. We ARE saying that any gas given in first gear is a waste. You are really sitting here telling me that with 450rwtq (and it's funny to think that 450rwtq isn't even that much), in your go kart of a car, you can come off idle on the street (or from a roll in 1st), nail it, and not spin?

I just, well, I really just don't know what to say or how to even respond to you. Congrats I guess. It's really an amazing accomplishment.

I keep my tires aired up and they do not suck. You clearly have no experience with the Mickey Thompson tires. They actually handle pretty good with air in them. Sorry your first gear is a waste but I assure you mine is not. Yes I can come off idle and from a slow roll in first, nail the gas and not spin. The front end feels like its about to come off the ground but it does not spin.

If you dont believe me your welcome to take it for a spin and I will show you the miracle that we call first gear.

[SPF1061]

Originally Posted by mpanten

I keep my tires aired up and they do not suck. You clearly have no experience with the Mickey Thompson tires. They actually handle pretty good with air in them. Sorry your first gear is a waste but I assure you mine is not. Yes I can come off idle and from a slow roll in first, nail the gas and not spin. The front end feels like its about to come off the ground but it does not spin.

If you dont believe me your welcome to take it for a spin and I will show you the miracle that we call first gear.

I also have a miracle called first gear, but mine thrives on a 3.27 rear axle ratio. I absolutely do not disbelieve you, but I do find it completely contrary to my experience. I wonder what engine you are running? Is it possible that you are running a peaky motor? I have run the M/Ts on my car and can smoke them at will in low gear above 2000/2500 rpm with a fully engaged clutch. I am quite jealous of the incredible traction you are achieving and want some for myself!

[mpanten]

[quote=SPF1061;1233688]I also have a miracle called first gear, but mine thrives on a 3.27 rear axle ratio. I absolutely do not disbelieve you, but I do find it completely contrary to my experience. I wonder what engine you are running? Is it possible that you are running a peaky motor? I have run the M/Ts on my car and can smoke them at will in low gear above 2000/2500 rpm with a fully engaged clutch. I am quite jealous of the incredible traction you are achieving and want some for myself![/QUOTE

my motor is aluminum stroket 427 windsor. 420-475 rwhp depending on the dyno. Its definately not a low end big block torque monster but I dont think its that out of the ordinary though. Power comes in about 2k and really hits at 3500 through 6500. I switched from a 3.27 to 3.37 and honestly it was not as big of change as I thought it would be. I wish I would have went 3.90 to 4.10.

[itstock]

[quote=mpanten;1233691]

Originally Posted by SPF1061

I also have a miracle called first gear, but mine thrives on a 3.27 rear axle ratio. I absolutely do not disbelieve you, but I do find it completely contrary to my experience. I wonder what engine you are running? Is it possible that you are running a peaky motor? I have run the M/Ts on my car and can smoke them at will in low gear above 2000/2500 rpm with a fully engaged clutch. I am quite jealous of the incredible traction you are achieving and want some for myself![/QUOTE

my motor is aluminum stroket 427 windsor. 420-475 rwhp depending on the dyno. Its definately not a low end big block torque monster but I dont think its that out of the ordinary though. Power comes in about 2k and really hits at 3500 through 6500. I switched from a 3.27 to 3.37 and honestly it was not as big of change as I thought it would be. I wish I would have went 3.90 to 4.10.

Wait, you don't even have 4.10's?????

I don't even know what you are arguing...

[AL427SBF]

Lots of burn outs from London, OH. Ford Shelby Cobra show
Lots of burn outs from London, OH. Ford Shelby Cobra show - YouTube


If I were a gamblin' man, and had to pick the neighborhood of the rearend (3.27 or 4.10), I'd pin the tail on the donkey like this ...


Car #1 - 3.27
Car #2 - 3.27
Car #3 - 4.10
Car #4 - 4.10
Car #5 - 3.27 (coupe)
Car #6 - 3.27
Car #7 - 4.10
... and so on


Personally, I would rather meter the clutch a little until she hooks up for a catapult launch vs. shifting into 2nd after 30', but that's just me

[itstock]

Originally Posted by mpanten

I keep my tires aired up and they do not suck. You clearly have no experience with the Mickey Thompson tires. They actually handle pretty good with air in them. Sorry your first gear is a waste but I assure you mine is not. Yes I can come off idle and from a slow roll in first, nail the gas and not spin. The front end feels like its about to come off the ground but it does not spin.

If you dont believe me your welcome to take it for a spin and I will show you the miracle that we call first gear.

I actually have quite a bit of experience with the mickeys, both the streets and the street radials.

Aired down a little with drag radials the car should hook up from a roll with 3.55s or higher. 4.10s no, unless they are heated up a lot (talking specifically for our sbf 427s). Off idle punching, it's going t spin.

Anyway, that got off tangent quick. I added my 2 cents and hopefully future readers use an ounce of common sense to figure out what is being discussed (specifically the definition of "useless" when referring to 450rwtq with 4.10s on the street, in first gear).

[joyridin']

I had 4.56 rear gears in my car with T56. First gear was useless, but 6th gear (.54) was great.

I now have switched to 3.73, so we will see what happens this Summer.

I would go with 4.10's without a problem.

[D-CEL]

Lets see, I posted this pic on 5-15-2005,

And this one was posted on 7-19-2102.

The only thing that hasn’t changed is the tire. This is my second set of M/Ts (325-50-15) in near 25k miles. I drive my car a lot and hard for a street car. Lots of canyon, lots sprinting so I am fairly familiar with them. The tire, gear and motor combo just plain work.
Yes they can be snapped loose in first gear if you want to. But they heat up fast and will hook second gear hard, with not a wiggle in third.
As I recall Greg used to run ET Street Radials (like me) not ET Streets with his best times on 275s
I have run ET Street on other cars, but not on a car I expected to turn a corner.

[roadrod2000]

rgnbull1227, It looks like I have a very similar set up to what you will have with the 4.10 ratio, so here goes,
My car has a 4.27 ratio rear with a world class T-5 trans, the engine is a 289 HiPo with iron heads, dual quads and a pretty wild cam, I don't know the HP or Torque but would guess HP at someware between 350 and 400 and torque on the lower end of things. I had concerns with the 4.27s during the (rebuild) of my car, but figured that the high rpm 289 would take care of that.
The gear ratio chart that you supplied looks almost identical to mine because his transmission apears to be a slightly wider ratio making the overall first gear for you accually lower than mine (I'm at 12.596 compound)
I'll sum it up for comparison reasons going off the info on the chart
Your 1st gear -lower than mine
Your 2nd gear- slightly lower than mine
Your 3rd gear- slightly higher than mine
Your 4th gear- slightly higher than mine
Your 5th gear- slightly lower than mine
Here is what I experience driving the car around town; From a stop I always use first gear but could easily start out in second, I don’t wind it out in first so the shift to second is done before I’m halfway through an intersection, of the few times that I have nailed it in first I’m at the rev limiter (7000 rpm) before I even have time to shift. Driving around town with speeds at 45-50 I am in 4th gear with the engine at 2500-2800 rpm (a nice sound at this speed but a little high for just cruising to the coffee shop) the jump to 5th drops my rpm at 50 to 1755 ( a little low for my engine to remain happy) so for me around town I would be happier with the 3rd 4th and 5th that you will end up with but not the 1st or 2nd.
On the freeway at 65 to 70 I’m at 2280-2450 which is not bad with my engine.
Bottom line is that if I change things (and I might) I would want to end up with higher ratios in 1st through 4th and keep 5th about the same but even with the low ratio that I have the car is capable of going much faster than I will probably ever drive it.
Hope this helps

[rgnbull1227]

Originally Posted by roadrod2000

rgnbull1227, It looks like I have a very similar set up to what you will have with the 4.10 ratio, so here goes,
My car has a 4.27 ratio rear with a world class T-5 trans, the engine is a 289 HiPo with iron heads, dual quads and a pretty wild cam, I don't know the HP or Torque but would guess HP at someware between 350 and 400 and torque on the lower end of things. I had concerns with the 4.27s during the (rebuild) of my car, but figured that the high rpm 289 would take care of that.
The gear ratio chart that you supplied looks almost identical to mine because his transmission apears to be a slightly wider ratio making the overall first gear for you accually lower than mine (I'm at 12.596 compound)
I'll sum it up for comparison reasons going off the info on the chart
Your 1st gear -lower than mine
Your 2nd gear- slightly lower than mine
Your 3rd gear- slightly higher than mine
Your 4th gear- slightly higher than mine
Your 5th gear- slightly lower than mine
Here is what I experience driving the car around town; From a stop I always use first gear but could easily start out in second, I don’t wind it out in first so the shift to second is done before I’m halfway through an intersection, of the few times that I have nailed it in first I’m at the rev limiter (7000 rpm) before I even have time to shift. Driving around town with speeds at 45-50 I am in 4th gear with the engine at 2500-2800 rpm (a nice sound at this speed but a little high for just cruising to the coffee shop) the jump to 5th drops my rpm at 50 to 1755 ( a little low for my engine to remain happy) so for me around town I would be happier with the 3rd 4th and 5th that you will end up with but not the 1st or 2nd.
On the freeway at 65 to 70 I’m at 2280-2450 which is not bad with my engine.
Bottom line is that if I change things (and I might) I would want to end up with higher ratios in 1st through 4th and keep 5th about the same but even with the low ratio that I have the car is capable of going much faster than I will probably ever drive it.
Hope this helps

Thanks Rod. What rear did you have previously to the 4.27?

[vector1]

if you look at the hp curve i would think the rpm drop on the upshift could be taken into account also. i like the spacing of 3,4,5 on a tko with .82 od, 4.10 would put these gears to use.

[roadrod2000]

Originally Posted by rgnbull1227

Thanks Rod. What rear did you have previously to the 4.27?

This is the only set I have used in the car, When I bought the car it was partially dismantled and some what of a basket case, it came to me with two rear end assemblies, the other one I have is a 3.54, when I did the calculations (same chart you used) I figured I was better off with the 4.27

[JBCOBRA]

D-Cel
Your car turned out Bad @ss!!!
Really Sweet

[D-CEL]

Thanks JB

The rebuild has re-lit the fire, Im getting all my new motor pieces out so I can get the crazy thing assembled finally. Maybe by the end of the year Ill have a new monster In it! lol

Jason

[rgnbull1227]

Opinions if these would be the correct gears for a 4.10 swap? Would this work for the rear in my car?
http://www.jcwhitney.com/motive-gear...lterid=d1836j1

[rgnbull1227]

Nevermind wrong gears. seems like these are the 3.91, but no 4.10's yet.

3.91 gto gears

[twin turbo]

D-cel, to be fair, part of the reason your tires work so well for you (besides being sticky and wide), is that they are 28" tall, which significantly changes the true ratio. I have 275/17 drag radials (25.7" tall), which are pretty common, and there is no chance in hell I would hook with 4.10's. Cheers.

[Dwight]

I'm car number 4 in the video, yellow Cobra with Alabama tag. I have 3:55 gears with 26" tires and a small block with a lot of low end torque. TKO 600 with the 2.97 1st gear. I sold my TKO with a 3.27 because first gear was useless.

There is no way I could use 4:10 gears in my Cobra. NO WAY

Dwight

(AL427SBF post)
Lots of burn outs from London, OH. Ford Shelby Cobra show
Lots of burn outs from London, OH. Ford Shelby Cobra show - YouTube


If I were a gamblin' man, and had to pick the neighborhood of the rearend (3.27 or 4.10), I'd pin the tail on the donkey like this ...


Car #1 - 3.27
Car #2 - 3.27
Car #3 - 4.10
Car #4 - 4.10
Car #5 - 3.27 (coupe)
Car #6 - 3.27
Car #7 - 4.10
... and so on


Personally, I would rather meter the clutch a little until she hooks up for a catapult launch vs. shifting into 2nd after 30', but that's just me

[Dwight]

I have 350 ft lbs of torque at 2200 rpms. Torque spins tires, not hp. My motor make all it's hp & tq before 5500 rpms. That makes for a great street motor. I can cruise in 5th (.68) at 1500 rpms and not have a trailer hitch jerk. Hiway speed 70 to 80 I'm about 2000 rpms.

Dwight

see ya in Ohio in June