3.73's driving performance

91BLOWNSC

Registered User
I was just wondering how the 3.73's will perform on say a 45mph downshift. I ask because with my current 3.27's I beleive it downshifts to the top of second and pulls very well for a bit before she goes into 3rd. With 3.73's, I asumme it will still shift to the top of second, but won't hold it as long. Will the car be slower from a roll as a result, or will the 3.73's put me farth up in RPM's in 3rd to make it faster. Im a little confused. Thanks guys!
 
The differince between the 3.27 and 3.73s is about 14%. You can look at it two ways...at the same MPH your engine will be revving 14% higher or at the same RPM your car will be moving 14% slower.

So for the example you listed about hitting the throttle at 45 mph, it should now do the same thing at 38.7 mph. IMO, The 3.73s are one of the best mods you can do on an AOD equipped SC.

David
 
i just put a 3.73 in my 91 auto. few months ago.it's great.alot quicker.car used to change to od at 45 mph now it changes at 35 mph.0-100 alot faster.dunno past 100 cuz i don't really go above that.no reason to.improved gas mileage alil too.
 
good question...

good question sc boobie :) i didn't think that there were any gears greater than 3.73 put in these stock..... make the car kick harder when you get on the gas....but mpg will suffer, since the car's goin slower at any given rpm.

dr feesh
 
3.73 from the factory

In 1990 I order an XR-7 with the 3.73 option and auto trans.

Mileage was 19 around town, 22 highway

It did shift in OD at 45

120 mph was 3400 rpm

The car was all stock. Unfortunately it died at 239,503 mile.

Maybe this helps
 
everybody knows with a gear in ur car u get better around town gas mileage cuz it's not as hard on the car taking off from lights and so on.but ur highway gas mileage will suffer alil cuz ur turning more rpms on interstate.but around town u don't have to hit the gas as hard to get up to around town speeds.so therefor u get better gas mileage read up on gears if u don't believe me.and yes i cruise in od at 35.i never change gears,even when i'm racing with anyone.i have beat a few mustang 5 speeds leaving it in od off the line.and that was before the gear.haven't really raced much since gear.i did beat a about 2000 mustang gt on the roll from about 25 mph.pulled him by about 1 1/2 car lengths on roll.then we raced from a light and i had bald tires on the back and he spun and i spun like hell.my front bumper was at his back bumper.then i finally hooked up and i stayed right there at his back bumper till i let off at about 75-80 mph.same day i went and bought 4 brand new bfgoodrich g forces 245/50/16.still looking for that guy again.but anyways i think the aod shifts fine when u leave it in od and race.plus it's not as hard on it too(has 190,000 miles on it)
 
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You're right SHO taurus because for best fuel mileage you need your gear matched to you torque peak of the engine, go to far either way and mileage suffers.
Does'nt matter what RPM you are turning at what speed if the engine is put in a strain from the gear.
 
ty mike 38sc...all 4 mustang 5.0's that i have owned,i've had 3.73 put in them.i really believe that is one of the best performance upgrades you can do for not big bucks.it's like night and day when u do it.i'm wanting a lightning soon.been doing alot of reading on them they all come with 3.73 from factory also.like the sounds and looks of the 2005 lightning.gonna have 500+ hp and over 500 tq. and 6 speed manual.here is a article on specs and pic of 2005 lightning.same engine that is in the new ford gt. http://www.trucktrend.com/features/tech/112_0309_amv8_dvr/ click on the pic of that engine and make it bigger.god it looks sweet.
 
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Yeah I'm a member of the SVTOA and we got pics and specs of the 05 Lightning back last Feb. and it looks good. But I'm not too sure how well the IRS is gonna work out in the truck, since the majority of the concensus around here say the IRS is holding back the SC in 1/4 mile times. I geuss were gonna see if that excuse will continue to fly or not when the Lightning reapears.

Edit: My SVT Contour came with 4.09 gears in it and its a hoot to drive.
 
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even the 02'to present lightning are sweet too.99-01 were 20 hp less but still nice trucks.i see online all the time how they do about $600 worth of mods to them and they run mid 12's all day long.not bad for a truck that outruns vette's and other sports cars,for just $600.i've test drove some 02' and they are super quick stock.can't wait to own one with some mods.
 
Yeah Lightnings are nice trucks but I'm just not a truck person. I'm trying but so far the only thing I like about them is that I can haul something that I dont normaly haul around but about every 8 years or so, other than that I dont like anything about them.LOL!!!!!:) But hey to each there own, trucks are very popular theres no denying it.

Geuss what.....Someone tried to steal a brand new Cobra with Mystic paint on it(only 2000 made) and drove it out the front windows of the dealership here. Once they shot out of the front of the building they started going down about 20' of concrete steps to get to the lot. They set the inertia switch off and the car was stuck on the steps.......of course the car was a total loss.
Apparentaly they had just watched gone in 60 seconds or something because it looked like something from the movie.
 
i just sold my mustang and i'm about thru with them.everybody and their mother has one.great cars but i just like to be alil different.that is why i bought the SHO and sc,cuz not to many of them.my 95 sho is a 5 speed.which is the last year of the 5 speeds and last year of the v6 sho.96 they went to that sucky v8 and only automatics.95 5 speeds they only made 2036 of them.and in 95 they were bug free.everybody says they are best year to get.i just want a lightning cuz it's different and not everybody has one.and not everybody knows what they are.it's funny when u beat someone and they pull up to the next light and is like what is that and what does that have in it.(SHO)i love beating 5.0's and ricers in it then at next light they are like what is that?they haven't a clue of what a sho is and they ask is that a 5.0?i'm like no just a lil v6 made by yamaha.and they are like u got a yamaha engine in that?how much did it cost u to put that in?and i didn't know yamaha made engines for cars...lol what tards.really like the looks of the young kids in the 5.0's @ next light they are all staring at the emblems and stuff.you don't know how many people tell me i have a 5.0 in it.i'm like does it sound like a 5.0?to me it sounds kinda like a motorcycle.i haven't changed the mufflers on the sho and sc cuz i hear everybody say how there sounds like a ricer after they do it.and i'm so anti ricer.i think they are the biggest tards and they believe that crap in the movies too much.god don't get me started on them.big coffee can mufflers and goofy 10' wings like that makes the car any faster.i just lmao everytime i see one and they just think they are so kool.lol.hey mike did yamaha make the 4 cyl for the svt contour?that is what u said u had right?i've heard they did but i didn't know.
 
The SVT Contour has a 2.5L V6 with DOHC's rated at 205 HP and its 5 speed. I call it the go kart! LOL!!!! Fun little car to drive.
I know what your saying about everybody having Mustangs, but there is an upside to that as well. Parts of ALL kinds are plentifull and the same cant be said for all cars.;) But then again for some people thats not too much of a problem either.
 
but did yamaha work with the svt guys designing that coutour engine?i've also heard the same thing about the 03 cobra engine that yamaha worked with ford designing that motor too.dunno... :confused:
 
Sorry sho taurus, never meant to imply I thought you were crazy!
:rolleyes:

So 3.73 gears will not reduce gas mileage- cool. How do they affect highway driving? If your doing 75mph in OD, what is your rpm?

How do the 3.73 gears compare to 3.55's I wonder...
 
Ford kinda owns Mazda(A good prtion of it) so it goes both ways..From what I know its the head desighn of the SHO that Mazda helped in..Nothing about the 03 Cobra that Mazda could have helped with..Its basically the same motor as the year before ..A tad beefier..A tad redesighned with a SC on it...So dont go thinking YAMAHA is what makes a ford fast....hmmphh
 
Damon is right Yamaha has nothing to do with the Cobra motor.
The whole thing started when Ford contracted Porche to build the first Duratec V6 motor prototype. They built both 2.0L and a 2.5L prototype engines and did alot of testing on them. Ford then took the prototypes and all the R&D back and turned there engineers loose on it to polish it out and get it ready for production. That engine became the Duratec which is a modular V6 and SVT souped some up to put in the Contours.
But some time after the Duratec was in production Yamaha was approached to see what they could do with the basic design of the prototype Duratecs Hence the SHO version was born.
The 2 engines are cousins, they got the same genes but different daddy's.
Yamaha did have a small hand in the modular engine design that Ford uses today. Most of there involvement was with the block and the main cap assembly in those engines and thats about it.
 
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