Gears

I have a 93 5.0 with 8# KB blower, tuned, runs great.

I was wondering about putting in gears, it has stock gears now.

Questions are what gear ratio is stock, and what gear ratio is good for the
extra torque, and is still usable at 80 MPH highway speeds?
I don't want to go too tall as it would be high in the RPM at high speed.
And is it worth the effort?

I use it as a daily driver around town, just need to get there a little
quicker.
About how much should it cost if I have a shop do it ?


Thanks in advance

Mike Coel wrote:
> I have a 93 5.0 with 8# KB blower, tuned, runs great.
>
> I was wondering about putting in gears, it has stock gears now.
>
> Questions are what gear ratio is stock, and what gear ratio is good for the
> extra torque, and is still usable at 80 MPH highway speeds?
> I don't want to go too tall as it would be high in the RPM at high speed.
> And is it worth the effort?

I have 3.55 gears in my '89 LX that has a KB blower. I wouldn't go any
steeper and, IMO, I recommend 3.08s or 3.27s. I factory ordered my car
and specified the 3.08 optional gears. I probably should have kept
them. If you have a manual tranny then you likely have 2.73s. If you
have an automatic then they are probably 3.27s or maybe 3.08s and I
would leave them alone.

> I use it as a daily driver around town, just need to get there a little
> quicker.
> About how much should it cost if I have a shop do it ?

A gear swap runs about $400 including parts and labor. Get is done by
someone that knows how to do it or you'll have nothing but trouble.
While your at it have them replace the clutch packs in the differential.
Yours are like worn down if you stock have the stock differential
clutches installed.

Mike Coel wrote:
> I have a 93 5.0 with 8# KB blower, tuned, runs
> great.
>
> I was wondering about putting in gears, it has
> stock gears now.
>
> Questions are what gear ratio is stock, and what
> gear ratio is good
> for the extra torque, and is still usable at 80
> MPH highway speeds?
> I don't want to go too tall as it would be high
> in the RPM at high
> speed. And is it worth the effort?
>
> I use it as a daily driver around town, just
> need to get there a
> little quicker.
> About how much should it cost if I have a shop
> do it ?
>
>
> Thanks in advance

--

Lower gears are usually a darn good idea. For
driving around town, you might find that you get
better gas mileage. Maybe.

Your highway speed depends on tire size. But with
a 25" tall tire and a .68 OD gear, your rpm at
80mph would look something like this (give or
take):

3.08 2150
3.55 2500
3.73 2650
4.10 2900

As for cost, the most cost effective way to do it
is to swap a new rear end housing with LSD center
section for $800. Add your axles and brakes and
your set. If you can handle a wrench, you can do
this yourself.

--------
..boB
2006 FXDI hot rod
2008 Mustang Coupe
2001 Dodge Dakota QC 5.9/4x4/3.92
1966 Mustang Coupe - Daily Driver
1965 FFR Cobra - 427W EFI, Damn Fast.

Michael Johnson > wrote in
:

> Mike Coel wrote:
>> I have a 93 5.0 with 8# KB blower, tuned, runs great.
>>
>> I was wondering about putting in gears, it has stock gears now.
>>
>> Questions are what gear ratio is stock, and what gear ratio is good
>> for the extra torque, and is still usable at 80 MPH highway speeds?
>> I don't want to go too tall as it would be high in the RPM at high
>> speed. And is it worth the effort?
>
> I have 3.55 gears in my '89 LX that has a KB blower. I wouldn't go
> any steeper and, IMO, I recommend 3.08s or 3.27s. I factory ordered
> my car and specified the 3.08 optional gears. I probably should have
> kept them. If you have a manual tranny then you likely have 2.73s.
> If you have an automatic then they are probably 3.27s or maybe 3.08s
> and I would leave them alone.

My '93 AOD came with 2.73s from the factory; I went up to 3.73s with an
Auburn and it's perfect IMO. That said, I don't have a blower. The car
can run 80mph all day long with no problem. Mileage is between 15 and
20 depending on how I drive.

As Michael has suggested, 3.55s are probably as numerically high as
you'd want to go (especially if you have a stick), given the extra
torque courtesy of the KB.


>> I use it as a daily driver around town, just need to get there a
>> little quicker.
>> About how much should it cost if I have a shop do it ?
>
> A gear swap runs about $400 including parts and labor. Get is done by
> someone that knows how to do it or you'll have nothing but trouble.
> While your at it have them replace the clutch packs in the
> differential.
> Yours are like worn down if you stock have the stock differential
> clutches installed.

My Auburn is coming up on 10 years now, and it's been perfect. I doubt
I could say the same for a rebuilt OEM rear.

Joe wrote:
> Michael Johnson > wrote in
> :
>
>> Mike Coel wrote:
>>> I have a 93 5.0 with 8# KB blower, tuned, runs great.
>>>
>>> I was wondering about putting in gears, it has stock gears now.
>>>
>>> Questions are what gear ratio is stock, and what gear ratio is good
>>> for the extra torque, and is still usable at 80 MPH highway speeds?
>>> I don't want to go too tall as it would be high in the RPM at high
>>> speed. And is it worth the effort?
>> I have 3.55 gears in my '89 LX that has a KB blower. I wouldn't go
>> any steeper and, IMO, I recommend 3.08s or 3.27s. I factory ordered
>> my car and specified the 3.08 optional gears. I probably should have
>> kept them. If you have a manual tranny then you likely have 2.73s.
>> If you have an automatic then they are probably 3.27s or maybe 3.08s
>> and I would leave them alone.
>
> My '93 AOD came with 2.73s from the factory; I went up to 3.73s with an
> Auburn and it's perfect IMO. That said, I don't have a blower. The car
> can run 80mph all day long with no problem. Mileage is between 15 and
> 20 depending on how I drive.
>
> As Michael has suggested, 3.55s are probably as numerically high as
> you'd want to go (especially if you have a stick), given the extra
> torque courtesy of the KB.

You hit the point I failed to make. With a KB blower the low end torque
is so great the higher (numerically) gears are not needed and will cause
massive wheel spin on launching. The 3.55s are really too much for my
taste but not not bad enough to warrant changing them.

>>> I use it as a daily driver around town, just need to get there a
>>> little quicker.
>>> About how much should it cost if I have a shop do it ?
>> A gear swap runs about $400 including parts and labor. Get is done by
>> someone that knows how to do it or you'll have nothing but trouble.
>> While your at it have them replace the clutch packs in the
>> differential.
>> Yours are like worn down if you stock have the stock differential
>> clutches installed.
>
> My Auburn is coming up on 10 years now, and it's been perfect. I doubt
> I could say the same for a rebuilt OEM rear.

The clutches in the OEM differentials do wear over time. New clutch
packs are cheap and with the rear end apart it is a good time to replace
them. I really like the Torsen differentials as they adjust to give
more torque to the wheel with the most traction. It makes them great
for carving corners and going in a straight line. They are a little
pricey though.

On Fri, 7 Mar 2008 22:54:56 -0600, "Mike Coel" >
wrote:

>I have a 93 5.0 with 8# KB blower, tuned, runs great.
>
>I was wondering about putting in gears, it has stock gears now.
>
>Questions are what gear ratio is stock, and what gear ratio is good for the
>extra torque, and is still usable at 80 MPH highway speeds?
>I don't want to go too tall as it would be high in the RPM at high speed.
>And is it worth the effort?
>
>I use it as a daily driver around town, just need to get there a little
>quicker.
>About how much should it cost if I have a shop do it ?
>
>
>Thanks in advance
>
If it's a daily driver used around town, you're not likely to get
there any quicker. In fact, if you try, it may take you considerably
longer while the traffic cop writes out the ticket. And it's quite
possible it's going to cost you more for the change on top of the fine
and insurance increase :0) Happy Motoring.