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3.73 or 3.90?

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  #1  
Old 04-07-2005 | 07:12 AM
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Speed Demon
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From: Austin, TX
Cool 3.73 or 3.90?

I wanted to know on an 02 GT 5-speed what gear ratio to go with. I do some highway driving everyday so i do not want 4.10's. I just need feedback to help me decide whether to go with 3.73's or 3.90's.
 
  #2  
Old 04-07-2005 | 07:39 AM
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Default go 390

i have a 98 gt with 390 gears and i love it. i went from 273 to 390 it was a big jump. i get 24mpg. on the highway cruising at 3000rpm at about 90mph.
i like them alot
 
  #3  
Old 04-07-2005 | 02:13 PM
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3.90's and a diablo predator and you're good to go!! Best upgrad I've done so far!! Big SOTP feel!!
 
  #4  
Old 04-07-2005 | 06:53 PM
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I have 3.73 gears now and they work well with My near stock engine. I likley will go to 4.10's when I get ported heads and cams so I can take better advantage of the improved top end power.
 
  #5  
Old 04-11-2005 | 02:01 AM
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don't waste time with either. Do 4.10's now, or do the later. Eventually you'll want them anyway. Some guys with mods are even running 4.30's and love em. 3.73's and 3.90's don't cut it.
 
  #6  
Old 04-11-2005 | 09:58 AM
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I had 3.73's and swapped them out for 4.30's. But I race alot at the track. Really depends on what your goals are.
 
  #7  
Old 04-16-2005 | 09:16 PM
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I will be discarding my 3.73 gears this week and installing 4.10 gears instead. I wish I didn't waste my money on the 3.73 gears (even though I can probably resell them) and wasted my money on having to buy another install kit and 3 more quarts of synthetic fluid and my 3 hours of labor for the install. If you are so dead against installing the 4.10 gears you should go with at least 3.90.
 
  #8  
Old 04-16-2005 | 10:48 PM
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What are the FACTS about the negative aspects of 4.10 gears. Just the facts please!
 
  #9  
Old 04-17-2005 | 10:19 AM
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Other than a little more frequent upshifting in city driving (wich means you don't have to downshift as often either) you may notice 1 mpg less on the hwy? Most people who purchase the 4.10 gears never regret purchasing them and some people don't notice any difference in their gas mileage. I have heard of people that can still get 24 mpg on hwy at 70 mph with a 5 speed and 4.10 gears,not bad considering the car is only rated at about 25 or 26 mpg on hwy with stock gearing.
 
  #10  
Old 04-18-2005 | 05:44 PM
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Default Gears For Blue Thunder

I Will Have A Set Of Used 3.73 Gears Available Cheap After They're Removed 4.19.05 If Interested. 50.00 Plus Shipping. The gears are ford motor company
 
  #11  
Old 04-18-2005 | 07:32 PM
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on my auto if i get 3.73 itll be like running 3.90s or 3.55s i know that with an auto it goes either up or down a gear. i cant remeber which anyone know?
 
  #12  
Old 04-18-2005 | 09:10 PM
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The Auto Runs Higher Rpms In Overdrive Than The Manuel Trans When In 5th Gear. My 01 Auto With 3.73 Still Only Ran 3000 Rpms At 87 Mph When In Overdrive On The Freeway,with 4.10 Gears At 3000 Rpms I Should Be At About 79-80 Mph Aprox In Over Drive.
 
  #13  
Old 04-18-2005 | 09:42 PM
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Will the engine, running at a constant higher RPM, burn out quicker? Or can it have any negative effect down the road?
 
  #14  
Old 04-18-2005 | 11:47 PM
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Also, those of you who have gears, how much was it to install them?
 
  #15  
Old 04-19-2005 | 07:14 AM
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Gears wont kill your engine, and my install was 200 bucks. Get them FIRST, before ANY other mods, you will love them the most. Of all the money I spent on my car, they made it the most fun. Kinda wish I had 4.10's though...
 
  #16  
Old 04-19-2005 | 02:40 PM
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The Auto Runs Higher Rpms In Overdrive Than The Manuel Trans When In 5th Gear. My 01 Auto With 3.73 Still Only Ran 3000 Rpms At 87 Mph When In Overdrive On The Freeway,with 4.10 Gears At 3000 Rpms I Should Be At About 79-80 Mph Aprox In Over Drive.
why the hell do you type every first letter capital?
 
  #17  
Old 04-20-2005 | 12:01 AM
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Not sure why it came out that way,I don't remember purposely doing such a thing.Perhaps my computer does this or Mustang Tuning's site does this after a edit?
 
  #18  
Old 04-20-2005 | 09:29 PM
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I went from the stock 3.27 to 4.10s and my average gas mileage went up. I live in delaware and there isnt a lot of highway driving. My miles per gallon went up 2.3 MPG!!!!
 
  #19  
Old 04-23-2005 | 07:26 AM
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The 4.10 gears have been in now for 5 days and I haven't noticed any diffrence in my fuel economy,although it hasn't been checked accurately. My car has a auto and it had 3.73 gears,runs a little more rpm than I like on the freeway,I'm sure it wouldn't be near as bad with a 5 speed. The 4.10 gears do accelerate much harder out of the hole,3.90 gears are a nice compromise.
 
  #20  
Old 04-23-2005 | 07:50 AM
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I personally think 3.90's are a nice choice, but to be honest, they are not much different from a 4.10's. Rarely do you hear anyone saying that they have too much gear. I had this debate for months. Initially, I ordered 3.73's and then sent them back to MT for 4.10's. Now that I have 4.10's, I wish I had 4.30's. But, I also spray, so 4.10's is as high as I should be. Probably, 3.73 would be a better choice for me spraying, but for the 2 times a year I race at the track, 4.10's are a good choice for me as 99% of the time I am n/a.

If your are staying n/a, I strongly recomend 4.10's.
 
  #21  
Old 04-23-2005 | 08:00 AM
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here is another thing to consider, if you run a power adder going with a big gear 4.10-4.56 that you will most likly be out of rpms in 4th gear if you use a 26" tall tire if you go 28" you might have enough but i dought it. me i wont go higher than 3.73 as i am spraying mine. even then i dont think i am gonna swap gears. 3.27's rule with spray and my nittos.
 
  #22  
Old 04-23-2005 | 08:20 AM
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I believe the 3.90 gears are a nice compromise,they fall right between the 3.73 and 4.10 ratio even though some may call it splitting hairs. I also only go to the track once or twice a year but I also drive 20 miles of freeway everday to work and the traffic flow in my area is going 75-80 mph. I don't care about fuel economy, I would just like to have the engine turn a few less rpms on the freeway. I have a advantage over most people in that I work in a auto svc dept and have full access to hoists and tools and can do gear installs myself. Other than the price of a the gears and some lube and crush sleeve and bearing (200.00) The cost is peanuts to achieve what I want. Different strokes for different folks
 
  #23  
Old 04-23-2005 | 08:35 AM
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The N.H.R.A. drag racing rules that are applied at the track I go to state that a convertable (wich I own) can not go any faster than 13.99 without having a roll bar installed. I don't want a roll bar. Last year I ran 14.4 with 3.73 gears and now have installed a prochamber,underdrive pullies,Accufab plenum and 75 mm throtle body and deeper gears. Although I haven't been to the strip yet,I believe I will be close to 14.0 flat now.
 
  #24  
Old 04-26-2005 | 06:10 PM
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Originally Posted by MT's#1Customer!
I personally think 3.90's are a nice choice, but to be honest, they are not much different from a 4.10's. Rarely do you hear anyone saying that they have too much gear. I had this debate for months. Initially, I ordered 3.73's and then sent them back to MT for 4.10's. Now that I have 4.10's, I wish I had 4.30's. But, I also spray, so 4.10's is as high as I should be. Probably, 3.73 would be a better choice for me spraying, but for the 2 times a year I race at the track, 4.10's are a good choice for me as 99% of the time I am n/a.

If your are staying n/a, I strongly recomend 4.10's.

Either way you are still good to 130 or 140 mph+ right?
 
  #25  
Old 04-26-2005 | 06:16 PM
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Not sure what the top speed is,I would guess it will do 125 or little more with 4.10 gears. I have never topped the car out with any of the gear combo's I've tryed.
 
  #26  
Old 04-28-2005 | 06:49 PM
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my cars hits 135 at about 4600 rmps in overdrive with 4.10s theres no way you could hit that unless mabye with a 5 speed
 
  #27  
Old 04-29-2005 | 07:23 AM
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Never Say There Is No Way.
 
  #28  
Old 04-30-2005 | 10:28 AM
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i have a 96 stan gt 5-speed so if i were to get 3.90 gears what would all the pros and cons be for these like gas mileage highway and city , riding type etc... thanks guys
 




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