3:73 vs 4:10 gears????

Pulled my motor, rebuild in progress, the remaining decision, rear end gears....

I read an article that stated with a 5 speed and 4:10's my motor should run at about 2200 RPM's at 65 MPH... if this # is correct, that's seems ok for street use, a bit high, but not bad (and the launch should be awesome, if I can get the traction, currently running 50's on the rear)

my question for the guys running, 4:10's or 3:73's.. is this RPM # correct??? or should I opt for the 3:73's....

Input please.....

thx in advance...

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Black, 84 GT, ground effects, shorty headers, dual exh., rear spoiler from a 87, just getting started...

[Rick 91GT]

Go with the 4:10's if you plan on staying NA, if a blower is in the near future get 3:73's. The 4:10's will be fine on the street and with a 5spd, I only turn around 1700-1800 in 5th gear with my 3:73's at 65-70mph. I am going with 4:30 gears which will suit my combo, run around 2300-2400 at 65mph I think around 6300 through the traps.

Good Luck on the new combo

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Check Out My Site 91GT,Holley SysteMAX II Kit-Heads 2.02" x 1.60" port matched to a 1262,Anderson N-61,24#,76mm C&L,Full MAC exhaust 1-5/8" Long tubes,2-1/2" O.R H-Pipe,2 1/2" cat back, No A/C or PS or emissions, 12" K&N Filter,RNH PERFORMANCE Ram Air,Ron Davis Radiator,Full Suspension,S&W 8pt "X" brace,JAZ seats,3:73's,Welds..etc,4:30's and 31 splines coming very soon!

thx Rick, I was hopin the article was correct....

[Rick 91GT]

Forgot to tell you those were with 26" tall tires, a low profile tire will make it run like it has taller gears (EXAMPLE- 3:73s feel like 4:10's with 24" tires) a taller tires calms the taller gears down.

[GreeceLightning]

Are you guys serious? My rear end gearing is 4.08 stock on my 240sx, and I thought that your Mustang's must've been using a different scale, because a Mustang stock is 2.8x or something I believe. At 70mph in 5th gear, I'm at 3k rpm. I'm fine with that, it's not a problem. So it sounds like 4.10 would be good (streetable) in a Mustang? And what effect would a blower create? Thanks.

[red82gt]

Remember, a 240 sx has half as much torque as a mustang, not to mention that the transmission ratios are different, basically its apples to oranges.

jerryIII, if I didn't do a lot of highway driving I'd probably have 410's or 430's with my combo.

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GT-40 heads (ported, polished, + milled), B303 cam, 1.7rr's, JE pistons, Offy intake, Carter AFB 625cfm carb, Flowtech 1 5/8" shortys, Flowtech X-pipe, MAC Flowpath exhaust, MAC pulleys, 373's, subframes, Eibachs+Tokicos, B&M ripper, FMS Clutch, Zoom Quadrant+cable, 17" CSA Ultra rims, 235/45ZR17 Yokohama AVS S4's, MSD 6A ignition+coil, FMS 9mm wires, Carbed, Naturally Aspirated, and Nasty!

Red, my drive is 35 miles one way, 50% highway, i was'nt sure 4:10's would work, but after the replies and some additional conversation with other Mustang people, i will be happy.... Just not sure what i'll do after i get used to the new gearing....

NOS perhaps????

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Black, 84 GT, ground effects, shorty headers, dual exh., rear spoiler from a 87, just getting started...

[red82gt]

You'll be happy with the 410's. Truth be told, I bought my 8.8 rear fitted with a torsen diff and Richmond 373's for a price I couildn't afford to pass up so that's why I have the 373's.

[K-9]

So far the general consensus I've seen is that autos do well with 4.10's and manuals do well with 3.73. Is this right?

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K-9
No 'Stang just yet, but looking.