3.73's too much for a built engine?

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Bigstang1

Founding Member

Aug 28, 2002

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Massachusettes

Nov 4, 2004

#1

• Nov 4, 2004

• #1

Im sorry if this has been asked before but it seems that when ever i see a stang with a built motor (h/c/i) or a 351 they hardly ever run 3.73s with a 5 speed? Why is this? Is it because the motor has enough power not to need the extra gear? I am planning to get gears in the spring and was wondering what to go with if i will be building a motor eventually. i dont want to have to change them out again after i do up the motor. The car is street driven / daily driver in the summer. Any input would be great. thanks

 

N

Notched

New Member

Apr 1, 2004

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Nov 4, 2004

#2

• Nov 4, 2004

• #2

well im by no means a pro.. a built motor for a daily driver. 3.73 should be fine. saves you on gas and u still get some extra "get up and go" type deal. most people use 4.10's, or so i've heard just so it can go faster. dont take my word for it, im just going on what i've been told. it all depends i guess on where you wanna go with the car. eventually make it a strip car? street/strip? or just a daily driver.

 

281pony

Active Member

Aug 31, 2003

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46

Oly, WA

Nov 4, 2004

#3

• Nov 4, 2004

• #3

general rule of thumb is 3:55 or 3:73 for 5-speed, and 4:10 for auto.

some people use 3:55's in a manual like me, and some use 3:73. i got the car with 3:55's and have thought about going up to 3:73. you will want to keep 3:55 if your going to use a blower or possibly even an aggressive h/c/i car.

i do like 1800 rpm's at 80 with my 3:55's because of an extra low od, normally it would be around 2200ish, 3:73 would put you at 2400-2500 range. not sure if you drive on the freeway alot?

 

5spd GT

"the 5.0 owns all"

Founding Member

Aug 7, 2002

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Arkansas

Nov 4, 2004

#4

• Nov 4, 2004

• #4

Actually I would say with most of the h/c/i cars on here they have 373's or above...

I have 373's on my h/c/i car and I drive it every day...I would say it is right around the perfect gear for the car...

2000rpm at 60mph...

 

DMAN302

My mom says thanks for the pearl necklace.

Nov 8, 2003

2,120

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59

windsor, Canada

Nov 4, 2004

#5

• Nov 4, 2004

• #5

H/C/I cars tend to have the power up higher in the RPM range..like 2000-6000 so the higher gear like 3.73 gets you up there faster and keeps you in the high end of the powerband. IMO the higher gear is the only way to go on the street unless your running a blower or turbo where power and torque can be found lower in the band.

 

N8Miller

I need NOS....make it 2 of the big ones

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Jul 26, 2000

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Kingston, PA, USA

Nov 4, 2004

#6

• Nov 4, 2004

• #6

it all depends on the use.
rick91gt had 4.10s in his dads cobra that ran low 12s (+/- 125mph) with a blower. i think that im gonna keep the 4.10s in my car... it really likes them. If anything, ill invest in a taller tire to help ratio.

 

281pony

Active Member

Aug 31, 2003

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Oly, WA

Nov 4, 2004

#7

• Nov 4, 2004

• #7

yeah i forgot to add that in my last post.

my cam starts making power at 2200ish now, so thats the whole reason i was considering going up to a 3:73.

 

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SlowGT

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Jun 17, 1999

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Columbia Co, PA

Nov 4, 2004

#8

• Nov 4, 2004

• #8

88SC_GT said:

yeah i forgot to add that in my last post.

my cam starts making power at 2200ish now, so thats the whole reason i was considering going up to a 3:73.

Click to expand...

Centralia...which state?

 

281pony

Active Member

Aug 31, 2003

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Oly, WA

Nov 4, 2004

#9

• Nov 4, 2004

• #9

washington.

actually moved north about 20 miles of centralia now also.

 

Funanin

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Nov 26, 2001

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Horsham, Pennsylvania

Nov 4, 2004

#10

• Nov 4, 2004

• #10

If you want to put a blower on later then go with 3:55's. It will give u the little extra kick now that u will want until u get the blower, and once u get it, u will still have plenty of gear so u dont run out too fast like with 3:73, 3:90 or 4:10

 

S

SlowGT

Founding Member

Jun 17, 1999

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Columbia Co, PA

Nov 4, 2004

#11

• Nov 4, 2004

• #11

88SC_GT said:

washington.

actually moved north about 20 miles of centralia now also.

Click to expand...

we've got a Centralia ~20 miles from here, that's why I wondered

 

crazypete

All my crevices are greased.

Oct 22, 2004

930

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18

Arlington, MA

Nov 4, 2004

#12

• Nov 4, 2004

• #12

So what would be the point of decreasing returns?

I had originally intended to stay NA forever and with an automatic, the 4.56's are a good gear (maybe 4.30's if I had to go over again). But now I'm thinking that when I add more and more power, I will be limiting myself with gear. By the way, 4.56's are FUN. And I can drive around on the highway at 80 mph at 3k rpms for hours on end and it has PULL in overdrive and is always in its powerband. The highway cruising is the only reason I would have 4.30'ed it.

 

Hissing Cobra

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Jan 4, 2002

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Massachusetts

Nov 4, 2004

#13

• Nov 4, 2004

• #13

Yeah, I have the 4.30's in mine and I woudn't change a thing. It seems that N/A combo's love the 3.73's/4.10's/4.30's while the power added cars need less gearing (I would assume that the Turbo/blower/nitrous would make up the difference from lack of rpms.) As everyone knows, the N/A cars usually need higher rpms to get the power. For what it's worth, I shift mine at 6,800 rpm's. I'll be experimenting with a little higher shift next spring at the track.