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4:30 auto?

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Old Jan 16, 2008 | 10:31 PM
  #1  
Thief_of_Hearts's Avatar
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Default 4:30 auto?

what do you all think about 4:30s auto with torque converter,intake/tune for daily driving?
with the OD on will it still be hovering about 25-2600 rpm on the freeway??

I want something that will really scoot while being NA before getting forced induction,I'll change it back to stock gears or even 4:10s later on.

I want the most acceleration while being mainly very basic bolt ons,not trying to hit 12s or anything but just a real quick daily driver,stock tires and all.I am used to mostly mid-top end punch with my stage 2 srt(45-160) I want something real quick from a dead stop and won't mind if it slows down some around 120 or so..
Old Jan 16, 2008 | 10:40 PM
  #2  
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Default RE: 4:30 auto?

Well, your idle will probably significantly move up. Do you mind having like 3-4 less mpg? I think it would be cool, but you probably will be breaking the tires loose a lot.
Old Jan 16, 2008 | 11:04 PM
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Default RE: 4:30 auto?

4:10s sound like they would launch pretty hard but I want something that will launch out the hole like a bat outta hell.I don't mind upping the suspension some,the rear end and some stickier tires if it translates to greater traction and power to the ground off the line..
Old Jan 16, 2008 | 11:13 PM
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Default RE: 4:30 auto?

Thats what I have currently and I still drive mine to work once in a while (30+miles each way) and wherever else i feel like going in it. 2600rpms at 70mph and still get 17 mpg average...ands thats me driving like a squirrel.
in the heat of the summer 90+degrees+humid i ran 12.70's on the stock pirelli's and that was in full street trim..stock seats full exhaust spare tire etc.
the converter is definitely the thing that wakes up the autos. the gears do help but i didn't notice much difference at the track changing from 3.73's to 4.30's (maybe a tenth drop). if the car is a DD and you want to be able to set the cruise on 80mph and not kill the engine then stick with 3.73's or 3.90's.
3.73's at 80-85mph was 2600rpms

Old Jan 16, 2008 | 11:34 PM
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Default RE: 4:30 auto?

noice..so you don't reccommend even 4:10s for daily driving??
Old Jan 17, 2008 | 10:59 AM
  #6  
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Default RE: 4:30 auto?

I lost exactly 1mpg when I put on 4.10s (from 3.31). Why would he lose 3-4mpg with 4.30's?

I also daily drove with 4.10's flawlessly.
Old Jan 17, 2008 | 01:56 PM
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Default RE: 4:30 auto?

Just wondering this but do you even own an S197 yet? My suggestion would be to getyour car, own it, drive it and then decide on what gears you want.
It seems you post a lot of stuff with speculation and your plan for this car seems to be all over the place from what I have read you post on this forum.
Some of thepotential issues with 4.30 and automatic trannies would be higher RPMs at highway speeds, lower gas milage, a very very short first gear and increased trap speeds in 4th gear if you run at the track. If these are not issues for you then maybe that is a good gear ratio for you. I can tell you from experience that is a lot of gear for a daily driver. I have run 4.33 gears in a few of my GM muscle cars back in the seventies and it was too much gear for me back then.

I also daily drove with 4.10's flawlessly.
What kind of flaws are you referring to?


[/quote]
Old Jan 17, 2008 | 02:17 PM
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Default RE: 4:30 auto?


ORIGINAL: spyder7724

Thats what I have currently and I still drive mine to work once in a while (30+miles each way) and wherever else i feel like going in it. 2600rpms at 70mph and still get 17 mpg average...ands thats me driving like a squirrel.
in the heat of the summer 90+degrees+humid i ran 12.70's on the stock pirelli's and that was in full street trim..stock seats full exhaust spare tire etc.
the converter is definitely the thing that wakes up the autos. the gears do help but i didn't notice much difference at the track changing from 3.73's to 4.30's (maybe a tenth drop). if the car is a DD and you want to be able to set the cruise on 80mph and not kill the engine then stick with 3.73's or 3.90's.
3.73's at 80-85mph was 2600rpms

+1 - the stall in your converter is going to be the biggest factor...
Old Jan 17, 2008 | 07:53 PM
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Default RE: 4:30 auto?

I think the reason for that is that the transmission has a super low first gear (for an auto) like 3.25 or something so even with 3.31 or 3.55 gears it's equivelant to the older mustangs (2.74? low gear) having a set of 4.10's or 4.30's.
what i noticed with the swap from 3.31 to 3.73 was 3 tenths and 2-3 mph
then swap from 3.73 to 4.30's it dropped another tenth but gained about 4-5 mph cause it allowed the trans to lock up the converter in high gear before going through the finish line.
a good converter with a really good tune will change your car and really make it fun to drive.
unless you are going to race a lot i wouldn't advise going with the 4.30's.
Old Jan 17, 2008 | 08:55 PM
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Default RE: 4:30 auto?

ORIGINAL: zkiller

Just wondering this but do you even own an S197 yet? My suggestion would be to getyour car, own it, drive it and then decide on what gears you want.
It seems you post a lot of stuff with speculation and your plan for this car seems to be all over the place from what I have read you post on this forum.
Some of thepotential issues with 4.30 and automatic trannies would be higher RPMs at highway speeds, lower gas milage, a very very short first gear and increased trap speeds in 4th gear if you run at the track. If these are not issues for you then maybe that is a good gear ratio for you. I can tell you from experience that is a lot of gear for a daily driver. I have run 4.33 gears in a few of my GM muscle cars back in the seventies and it was too much gear for me back then.

I also daily drove with 4.10's flawlessly.
What kind of flaws are you referring to?

[/quote]

nope don't have the car yet..waiting for the snow to clear up.By then I will have plenty of money to mod..just want do real basic bolt ons,gears,torque converter and a tune.Not trying to break any personal records with the car but do want a decently quick daily driver.I just want something that will snap the tires loose and take off like a bat outta hell! so used to mid-top end with FWD turbo that I want something thats actually fast from a deadstop.



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