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Gears ?

  • Thread starter Thread starter 03REDFIRE
  • Start date Start date Nov 2, 2005

03REDFIRE

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  • Nov 2, 2005
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Im thinking of going with the 390's simply because I cannot make up my mind between 373's and 410's so 390's is the best bet question is where can I get the correct speedo gear for the 390's ?
 

CManT1914

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There is no speedo gear for 3.90's, the closest one they make is for 3.55's.
 

03REDFIRE

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CManT1914 said:
There is no speedo gear for 3.90's, the closest one they make is for 3.55's.
Click to expand...

Ok so Im clear on this If I used the 373's I would have to use the 355's also?

Man the levels of Lameness on this is staggering
 

CManT1914

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03REDFIRE said:
Ok so Im clear on this If I used the 373's I would have to use the 355's also?

Man the levels of Lameness on this is staggering
Click to expand...

Yep, that's the way I'm doing it now. It gets you close enough anyway. With my oversized tires though, I'm dead on, verified by those radar signs. With stock size tires, you'll only be a few mph at 70, so maybe 5 if you go 3.90's.

EDIT: Oh, I should say your speedo will read slightly higher than you're actually going. So you don't have to worry about getting pulled over for going faster than you think.
 

03REDFIRE

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http://steeda.com/store/-catalog/speedometer.htm


I found gear recal for 373's I think here If I went with 390's would I be better off getting the 410's gear they have or the 373?

Nevermind looking at thier chart 373+410s are the same white gear
 

CManT1914

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03REDFIRE said:
http://steeda.com/store/-catalog/speedometer.htm


I found gear recal for 373's I think here If I went with 390's would I be better off getting the 410's gear they have or the 373?

Nevermind looking at thier chart 373+410s are the same white gear
Click to expand...

lol, yep. 3.55's, 3.73's, and 4.10's all use the same white gear.

There is a way to go into the tranny and swap out the internal gears, but that's a lot of work for something so small.
 

95COBRA241

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You could always by a speed-cal from Dallas Mustangs or BBK. Its a lot more money than a gear but its supposed to be very accurate. Don't know if its for a 3.90 gear though. Do a search.
 

CManT1914

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95COBRA241 said:
You could always by a speed-cal from Dallas Mustangs or BBK. Its a lot more money than a gear but its supposed to be very accurate. Don't know if its for a 3.90 gear though. Do a search.
Click to expand...

Do speedcals work on ours since our speedo is mechanically driven? I was under the impression they worked only on 99+.

FWIW, they do have a setting for 3.90's. I helped install one on my friend's Mach 1, and it had a list of setting for different gears nearly a mile long.
 

mo_dingo

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Aug 26, 2003
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Nov 2, 2005
#9
  • Nov 2, 2005
  • #9
CManT1914 said:
Do speedcals work on ours since our speedo is mechanically driven? I was under the impression they worked only on 99+.

FWIW, they do have a setting for 3.90's. I helped install one on my friend's Mach 1, and it had a list of setting for different gears nearly a mile long.
Click to expand...

Yes they work.
Scott
 

GRGT1994

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Speed Cals work on our cars. I am running one. And they correct for virtually any gear set (adjustable by dip switches).

BTW, don't sweat the difference between 3.73 and 4.10. For a street car they are essentially identical. That is, the difference between stock gears and either 3.73 or 4.10s are so fantastically huge that it is meaningless to swet the difference between 3.73 and 4.10. Said another way, there is no difference you will ever perceive between a 3.90 and either 3.73 or 4.10 (even if you drove cars identically equiped except for the gears - one right after the other). So just pick one and go with it.

Not only that, but you can't get FRPP gears in 3.90. And you WANT FRPP.

IMHO, go with the 3.73. That will give you plenty of zip, and be marginally (MARGINALLY) more fuel efficient and driveable).
 

CManT1914

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#11
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GRGT1994 said:
Not only that, but you can't get FRPP gears in 3.90. And you WANT FRPP.
Click to expand...

I'm gonna disagree here, only because I have Richmonds and have ZERO whine. A few other guys who have them also have no problems. It all depends on who installs the gears, more than who makes the gears. Just IMHO.

Oh yea, thanks Scott and Brad for clearing that up about the speedcal!
 

GRGT1994

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  • Nov 3, 2005
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I hear you on the Richmonds. But FRPP are a ton easier to install for a newbie. That's why I would say definitely go with them. But either will work if a quality shop is doing your install.

I still can't see why people hem and haw over 3.73/3.90/4.10. Unless you are dialing in a bracket racer, the difference is not worth the thought energy. Just go 3.73.
 

CManT1914

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#13
  • Nov 3, 2005
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Oh yea, I remember now hearing about how FRPP's were easier to install. Funny how ford parts work best with other ford parts, lol. I had a shop do my gears and SFC's, those are the only things on my car I wouldn't touch.
 
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