speedometer gear

SN95 5.0 · 03-10-2001, 04:22 PM

I am going to be converting my 94 stang to 3.73s. I already bought the gear and pinion, but what do I make the speedometer accurate? Is it only one gear that needs to be switched for the speedometer? Thanks for your help. BTW, this is in a 5-speed car.

StreetStang37 · 03-10-2001, 09:24 PM

Is it the same in a '93. I'd like to know too.

------------------
1993 Mustang GT - March Ram Air & Pullies, K&N, C&L 73mm MAF, Super Competition Hooker Headers, 2 1/2 in. mandrel bent cat back, High Flow H-Pipe, Pro 5.0 Shifter, 16* Timing Advance

Unit 5302 · 03-10-2001, 10:34 PM

From what I remember the speedo gear for the standard T-5 is the "black" 20 tooth gear. Part number C1DZ-17271-A.

Correct me if I'm wrong?

I just used the search function to look up a related topic posted in Feb.

DemonGT · 03-10-2001, 10:58 PM

at MustangUnlimited for 3.73's the transmission gear is yellow part # F2674 and the speedometer gear is red part # F1302

transmission gear 7 teeth
speedometer gear 21 teeth

------------------
'91 GT,91K,T-5,air silencer removed,racing clutch(previous owner put in so dont know what kind),K&N air filter,Aiwa deck,power acoustic amp,2 12" pianeers,UPDATE: Just got my Mac long tube headers and Cat-back

Future Mods:3.73's,Pro 5.0,Shifter knob,FMS 9mm wires

cleanLX · 03-12-2001, 06:41 PM

DemonGT nailed it, unfortunatly your tranny has an 8 tooth gear. If you are not going to change the tranny gear, you need a 24 tooth speedo gear, which unfortunatly is not in existance, so you have to settle for a 23 tooth speedo gear that you can get from your Jeep dealership. Your speedo will be approx. 4% high with this combo.

Fox Body · 03-12-2001, 07:20 PM

Okay. Since we're on this topic....
The Mustang I'm driving has been converted from V6 to V8 (351W, yeah baby!!). Got 3.55s in an 8.8" and C4. Any body know what speedo gear I'll need. Thank you thank you.

P.S. I didn't know you need one for both tranny and speedo.(?) Will I need one for both?

-------------------------------
'79 Mustang Coup
4" Cowl
Weld wheels (15x6;15x8)
Stock 5.8L
C4 w/ shift kit
1.5" MAC full length headers
Holley 750 CFM
Edelbrock intake
2.5" Off road H-pipe, 2-chamber Flowmasters
8.8" Rear end w/ 3.55 gears (Now that's more like it!!)

Front: 225/60/15 Rear: 255/60/15 Eagle GT II
14 x 4” K&N air filter (getting the Xtreme setup soon)

"Red, thou art my companion. Hasten now your quickened metamorphosis to Green that I may conquer all who dare abide there beside me. May they be left thither behind burnt black." ---Fox Body

03-12-2001, 10:01 PM

can some one take me through the steps to install the speedo gear on a 95 mustang gt
with an aode tranny i already installed 3.55
gears and have bought the correct speedo gear
i just dont know how to put it in

DemonGT · 03-12-2001, 10:15 PM

when i get my 3.73's do i need the trany gear and speedo gear? or just the speedogear

------------------
'91 GT,91K,T-5,air silencer removed,racing clutch(previous owner put in so dont know what kind),K&N air filter,Aiwa deck,power acoustic amp,2 12" pianeers,UPDATE: Just got my Mac long tube headers and Cat-back

Future Mods:3.73's,Pro 5.0,Shifter knob,FMS 9mm wires

SN95 5.0 · 03-15-2001, 12:07 AM

Quote:

Originally posted by cleanLX:
DemonGT nailed it, unfortunatly your tranny has an 8 tooth gear. If you are not going to change the tranny gear, you need a 24 tooth speedo gear, which unfortunatly is not in existance, so you have to settle for a 23 tooth speedo gear that you can get from your Jeep dealership. Your speedo will be approx. 4% high with this combo.

So the speedo gear is the only gear that needs to be changed? The tranny gear doesn't need to be swapped? Is this correct?

Greg

stangbang · 03-15-2001, 07:20 PM

Check out www.hanlonmotorsports.com
They have a web page that will calculate the driven and drive speedo gears that you need based on what size rear tires and ring&pinion gears you have.

cleanLX · 03-15-2001, 07:46 PM

the 4% calc. is assuming 245/50r16's out back. (my situation) which are 25.7", which is 0.1" smaller than 225/55r16's according to bfgoodrich's site info. for me it was not worth the hassel (not real mecanically inclined) of swapping out the tranny gear for the 4%. Never took the time to figure it out, but I'm betting the 7 tooth tranny with the 21 tooth speedo is not much closer than 4% given the diff. in tire sizes.
there is a formula in the FoMoCo wish book to figure all this stuff out. I can post it when i get home.
Bye for now...

cleanLX · 03-15-2001, 07:57 PM

intrestingly enough, the link above does not use the 23 tooth gear in any of the calcs, and the 23 tooth gear IS a closer match than the 7 tooth tranny 21 tooth speedo combination given the 245/50r16's. They must not use the 23 tooth because it is not offered by ford or something?

[This message has been edited by cleanLX (edited 03-15-2001).]

SN95 5.0 · 03-22-2001, 10:59 PM

so all i need is a 23-tooth speedo gear and no tranny gear needs to be changed. I would feel a whole lot more confident about this if a few people could confirm this to be correct.

Thanks guys.

Green92LX · 03-23-2001, 12:00 PM

Why a jeep dealer??? Is there a part number you can supply??? I'll order the sucker today!!! Also, how can the 23 tooth work with 8 tooth tranny gear...won't it jump around???

I am extremely interested because my car has had 3.73's since before I owned it, and the car is showing a hell of a lot more miles than it w=actually has on it.

I've gotten used to it, but its still something that erks me every now and then

------------------
1992 LX:V-1 S-Trim ,Edelbrock 6037 Heads,Cobra Intake,E-303,1.6 Rollers,65MM Holley TB, 75 MM Pro M Mass Air, 190 LPH FP,24 lb injectors,MSD 6A and BTM,BBK equal length shorties,offroad h-pipe,Mac Flowpath Mufflers,Pro 5.0, 3.73's,Motorsport "C" springs,welded subframe connectors,Ponies w/ 225/50 Nitto NT 450's on front,255/50 BFG Drags out back,93 Cobra Spoiler
Daily driver 89 Coupe:BBK shorties,offroad,flowturds with dumps,soon to be cyber green

Jeff Chambers · 03-23-2001, 02:28 PM

You can order the 23-tooth gear from Mustangs Unlimited. I've got the part number along with a javascript calculator on my website under the Tech Articles section. Check it out. It'll let you change the combinations, vary tire size and so on then return an error percentage for what you've selected.

------------------
Jeff Chambers
Trophy Stock #3
11.86 Seconds / 113.8 MPH
Chambers Racing Team

Green92LX · 03-23-2001, 02:42 PM

20 Bucks for the damn thing!!!!!!!!!!!!

------------------
1992 LX:V-1 S-Trim ,Edelbrock 6037 Heads,Cobra Intake,E-303,1.6 Rollers,65MM Holley TB, 75 MM Pro M Mass Air, 190 LPH FP,24 lb injectors,MSD 6A and BTM,BBK equal length shorties,offroad h-pipe,Mac Flowpath Mufflers,Pro 5.0, 3.73's,Motorsport "C" springs,welded subframe connectors,Ponies w/ 225/50 Nitto NT 450's on front,255/50 BFG Drags out back,93 Cobra Spoiler
Daily driver 89 Coupe:BBK shorties,offroad,flowturds with dumps,soon to be cyber green

Green92LX · 03-23-2001, 02:47 PM

Also, how many teeth should the factory gear have? I ordered it, so I hope it works...but my question still remains: How does a 23 tooth gear mesh with an 8 tooth?

------------------
1992 LX:V-1 S-Trim ,Edelbrock 6037 Heads,Cobra Intake,E-303,1.6 Rollers,65MM Holley TB, 75 MM Pro M Mass Air, 190 LPH FP,24 lb injectors,MSD 6A and BTM,BBK equal length shorties,offroad h-pipe,Mac Flowpath Mufflers,Pro 5.0, 3.73's,Motorsport "C" springs,welded subframe connectors,Ponies w/ 225/50 Nitto NT 450's on front,255/50 BFG Drags out back,93 Cobra Spoiler
Daily driver 89 Coupe:BBK shorties,offroad,flowturds with dumps,soon to be cyber green

Green92LX · 03-23-2001, 02:56 PM

And of course I kept reading AFTER I ordered it and it says the 23-tooth is short lived???

Does this mean I'm gonna have nice chunks of plastic floating around in my tranny?

------------------
1992 LX:V-1 S-Trim ,Edelbrock 6037 Heads,Cobra Intake,E-303,1.6 Rollers,65MM Holley TB, 75 MM Pro M Mass Air, 190 LPH FP,24 lb injectors,MSD 6A and BTM,BBK equal length shorties,offroad h-pipe,Mac Flowpath Mufflers,Pro 5.0, 3.73's,Motorsport "C" springs,welded subframe connectors,Ponies w/ 225/50 Nitto NT 450's on front,255/50 BFG Drags out back,93 Cobra Spoiler
Daily driver 89 Coupe:BBK shorties,offroad,flowturds with dumps,soon to be cyber green

Green92LX · 03-23-2001, 03:44 PM

OK...I chickened out and canceled the order

I just sat here and did some # crunching, and I figured out if I disconnect my speedo for the season, then I should be up to par on miles...

I'm just not to key on putting something in my car that I know will self-destruct

------------------
1992 LX:V-1 S-Trim ,Edelbrock 6037 Heads,Cobra Intake,E-303,1.6 Rollers,65MM Holley TB, 75 MM Pro M Mass Air, 190 LPH FP,24 lb injectors,MSD 6A and BTM,BBK equal length shorties,offroad h-pipe,Mac Flowpath Mufflers,Pro 5.0, 3.73's,Motorsport "C" springs,welded subframe connectors,Ponies w/ 225/50 Nitto NT 450's on front,255/50 BFG Drags out back,93 Cobra Spoiler
Daily driver 89 Coupe:BBK shorties,offroad,flowturds with dumps,soon to be cyber green

SN95 5.0 · 03-23-2001, 08:05 PM

I have an 8-tooth stock tranny drive gear, right? what is the stock speedo gear?

[This message has been edited by SN95 5.0 (edited 03-23-2001).]

03-10-2001, 04:22 PM	#1
SN95 5.0 Registered Member Join Date: Nov 2000 Location: Pelican Rapids, Minnesota Posts: 31	speedometer gear I am going to be converting my 94 stang to 3.73s. I already bought the gear and pinion, but what do I make the speedometer accurate? Is it only one gear that needs to be switched for the speedometer? Thanks for your help. BTW, this is in a 5-speed car.

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03-10-2001, 09:24 PM	#2
StreetStang37 Registered Member Join Date: Dec 2000 Location: San Jose, California USA Posts: 275	Is it the same in a '93. I'd like to know too. ------------------ 1993 Mustang GT - March Ram Air & Pullies, K&N, C&L 73mm MAF, Super Competition Hooker Headers, 2 1/2 in. mandrel bent cat back, High Flow H-Pipe, Pro 5.0 Shifter, 16* Timing Advance

03-10-2001, 10:34 PM	#3
Unit 5302 Registered Member Join Date: May 1999 Posts: 5,246	From what I remember the speedo gear for the standard T-5 is the "black" 20 tooth gear. Part number C1DZ-17271-A. Correct me if I'm wrong? I just used the search function to look up a related topic posted in Feb.

03-10-2001, 10:58 PM	#4
DemonGT Registered Member Join Date: Aug 2000 Location: Wisconsin Posts: 879	at MustangUnlimited for 3.73's the transmission gear is yellow part # F2674 and the speedometer gear is red part # F1302 transmission gear 7 teeth speedometer gear 21 teeth ------------------ '91 GT,91K,T-5,air silencer removed,racing clutch(previous owner put in so dont know what kind),K&N air filter,Aiwa deck,power acoustic amp,2 12" pianeers,UPDATE: Just got my Mac long tube headers and Cat-back Future Mods:3.73's,Pro 5.0,Shifter knob,FMS 9mm wires

03-12-2001, 06:41 PM	#5
cleanLX Registered Member Join Date: Aug 2000 Location: Phoenix Az. by way of fredericton, NB Canada Posts: 73	DemonGT nailed it, unfortunatly your tranny has an 8 tooth gear. If you are not going to change the tranny gear, you need a 24 tooth speedo gear, which unfortunatly is not in existance, so you have to settle for a 23 tooth speedo gear that you can get from your Jeep dealership. Your speedo will be approx. 4% high with this combo.

03-12-2001, 07:20 PM	#6
Fox Body Mustang Maniac Join Date: Sep 2000 Location: GA, U.S.A Posts: 2,266	Okay. Since we're on this topic.... The Mustang I'm driving has been converted from V6 to V8 (351W, yeah baby!!). Got 3.55s in an 8.8" and C4. Any body know what speedo gear I'll need. Thank you thank you. P.S. I didn't know you need one for both tranny and speedo.(?) Will I need one for both? ------------------------------- '79 Mustang Coup 4" Cowl Weld wheels (15x6;15x8) Stock 5.8L C4 w/ shift kit 1.5" MAC full length headers Holley 750 CFM Edelbrock intake 2.5" Off road H-pipe, 2-chamber Flowmasters 8.8" Rear end w/ 3.55 gears (Now that's more like it!!) Front: 225/60/15 Rear: 255/60/15 Eagle GT II 14 x 4” K&N air filter (getting the Xtreme setup soon) "Red, thou art my companion. Hasten now your quickened metamorphosis to Green that I may conquer all who dare abide there beside me. May they be left thither behind burnt black." ---Fox Body

03-12-2001, 10:01 PM	#7
nate andrus Guest Posts: n/a	can some one take me through the steps to install the speedo gear on a 95 mustang gt with an aode tranny i already installed 3.55 gears and have bought the correct speedo gear i just dont know how to put it in

03-12-2001, 10:15 PM	#8
DemonGT Registered Member Join Date: Aug 2000 Location: Wisconsin Posts: 879	when i get my 3.73's do i need the trany gear and speedo gear? or just the speedogear ------------------ '91 GT,91K,T-5,air silencer removed,racing clutch(previous owner put in so dont know what kind),K&N air filter,Aiwa deck,power acoustic amp,2 12" pianeers,UPDATE: Just got my Mac long tube headers and Cat-back Future Mods:3.73's,Pro 5.0,Shifter knob,FMS 9mm wires

03-15-2001, 07:20 PM	#10
stangbang Registered Member Join Date: Oct 1999 Location: brunswick,ohio Posts: 135	Check out www.hanlonmotorsports.com They have a web page that will calculate the driven and drive speedo gears that you need based on what size rear tires and ring&pinion gears you have.

03-15-2001, 07:46 PM	#11
cleanLX Registered Member Join Date: Aug 2000 Location: Phoenix Az. by way of fredericton, NB Canada Posts: 73	the 4% calc. is assuming 245/50r16's out back. (my situation) which are 25.7", which is 0.1" smaller than 225/55r16's according to bfgoodrich's site info. for me it was not worth the hassel (not real mecanically inclined) of swapping out the tranny gear for the 4%. Never took the time to figure it out, but I'm betting the 7 tooth tranny with the 21 tooth speedo is not much closer than 4% given the diff. in tire sizes. there is a formula in the FoMoCo wish book to figure all this stuff out. I can post it when i get home. Bye for now...

03-15-2001, 07:57 PM	#12
cleanLX Registered Member Join Date: Aug 2000 Location: Phoenix Az. by way of fredericton, NB Canada Posts: 73	intrestingly enough, the link above does not use the 23 tooth gear in any of the calcs, and the 23 tooth gear IS a closer match than the 7 tooth tranny 21 tooth speedo combination given the 245/50r16's. They must not use the 23 tooth because it is not offered by ford or something? [This message has been edited by cleanLX (edited 03-15-2001).]

03-22-2001, 10:59 PM	#13
SN95 5.0 Registered Member Join Date: Nov 2000 Location: Pelican Rapids, Minnesota Posts: 31	so all i need is a 23-tooth speedo gear and no tranny gear needs to be changed. I would feel a whole lot more confident about this if a few people could confirm this to be correct. Thanks guys.

03-23-2001, 12:00 PM	#14
Green92LX Registered Member Join Date: Jun 1999 Location: North Haven,CT Posts: 336	Why a jeep dealer??? Is there a part number you can supply??? I'll order the sucker today!!! Also, how can the 23 tooth work with 8 tooth tranny gear...won't it jump around??? I am extremely interested because my car has had 3.73's since before I owned it, and the car is showing a hell of a lot more miles than it w=actually has on it. I've gotten used to it, but its still something that erks me every now and then ------------------ 1992 LX:V-1 S-Trim ,Edelbrock 6037 Heads,Cobra Intake,E-303,1.6 Rollers,65MM Holley TB, 75 MM Pro M Mass Air, 190 LPH FP,24 lb injectors,MSD 6A and BTM,BBK equal length shorties,offroad h-pipe,Mac Flowpath Mufflers,Pro 5.0, 3.73's,Motorsport "C" springs,welded subframe connectors,Ponies w/ 225/50 Nitto NT 450's on front,255/50 BFG Drags out back,93 Cobra Spoiler Daily driver 89 Coupe:BBK shorties,offroad,flowturds with dumps,soon to be cyber green

03-23-2001, 02:28 PM	#15
Jeff Chambers Moderator Join Date: Aug 2000 Location: Milan, OH Posts: 2,699	You can order the 23-tooth gear from Mustangs Unlimited. I've got the part number along with a javascript calculator on my website under the Tech Articles section. Check it out. It'll let you change the combinations, vary tire size and so on then return an error percentage for what you've selected. ------------------ Jeff Chambers Trophy Stock #3 11.86 Seconds / 113.8 MPH Chambers Racing Team

03-23-2001, 02:42 PM	#16
Green92LX Registered Member Join Date: Jun 1999 Location: North Haven,CT Posts: 336	20 Bucks for the damn thing!!!!!!!!!!!! ------------------ 1992 LX:V-1 S-Trim ,Edelbrock 6037 Heads,Cobra Intake,E-303,1.6 Rollers,65MM Holley TB, 75 MM Pro M Mass Air, 190 LPH FP,24 lb injectors,MSD 6A and BTM,BBK equal length shorties,offroad h-pipe,Mac Flowpath Mufflers,Pro 5.0, 3.73's,Motorsport "C" springs,welded subframe connectors,Ponies w/ 225/50 Nitto NT 450's on front,255/50 BFG Drags out back,93 Cobra Spoiler Daily driver 89 Coupe:BBK shorties,offroad,flowturds with dumps,soon to be cyber green

03-23-2001, 02:47 PM	#17
Green92LX Registered Member Join Date: Jun 1999 Location: North Haven,CT Posts: 336	Also, how many teeth should the factory gear have? I ordered it, so I hope it works...but my question still remains: How does a 23 tooth gear mesh with an 8 tooth? ------------------ 1992 LX:V-1 S-Trim ,Edelbrock 6037 Heads,Cobra Intake,E-303,1.6 Rollers,65MM Holley TB, 75 MM Pro M Mass Air, 190 LPH FP,24 lb injectors,MSD 6A and BTM,BBK equal length shorties,offroad h-pipe,Mac Flowpath Mufflers,Pro 5.0, 3.73's,Motorsport "C" springs,welded subframe connectors,Ponies w/ 225/50 Nitto NT 450's on front,255/50 BFG Drags out back,93 Cobra Spoiler Daily driver 89 Coupe:BBK shorties,offroad,flowturds with dumps,soon to be cyber green

03-23-2001, 02:56 PM	#18
Green92LX Registered Member Join Date: Jun 1999 Location: North Haven,CT Posts: 336	And of course I kept reading AFTER I ordered it and it says the 23-tooth is short lived??? Does this mean I'm gonna have nice chunks of plastic floating around in my tranny? ------------------ 1992 LX:V-1 S-Trim ,Edelbrock 6037 Heads,Cobra Intake,E-303,1.6 Rollers,65MM Holley TB, 75 MM Pro M Mass Air, 190 LPH FP,24 lb injectors,MSD 6A and BTM,BBK equal length shorties,offroad h-pipe,Mac Flowpath Mufflers,Pro 5.0, 3.73's,Motorsport "C" springs,welded subframe connectors,Ponies w/ 225/50 Nitto NT 450's on front,255/50 BFG Drags out back,93 Cobra Spoiler Daily driver 89 Coupe:BBK shorties,offroad,flowturds with dumps,soon to be cyber green

03-23-2001, 03:44 PM	#19
Green92LX Registered Member Join Date: Jun 1999 Location: North Haven,CT Posts: 336	OK...I chickened out and canceled the order I just sat here and did some # crunching, and I figured out if I disconnect my speedo for the season, then I should be up to par on miles... I'm just not to key on putting something in my car that I know will self-destruct ------------------ 1992 LX:V-1 S-Trim ,Edelbrock 6037 Heads,Cobra Intake,E-303,1.6 Rollers,65MM Holley TB, 75 MM Pro M Mass Air, 190 LPH FP,24 lb injectors,MSD 6A and BTM,BBK equal length shorties,offroad h-pipe,Mac Flowpath Mufflers,Pro 5.0, 3.73's,Motorsport "C" springs,welded subframe connectors,Ponies w/ 225/50 Nitto NT 450's on front,255/50 BFG Drags out back,93 Cobra Spoiler Daily driver 89 Coupe:BBK shorties,offroad,flowturds with dumps,soon to be cyber green

03-23-2001, 08:05 PM	#20
SN95 5.0 Registered Member Join Date: Nov 2000 Location: Pelican Rapids, Minnesota Posts: 31	I have an 8-tooth stock tranny drive gear, right? what is the stock speedo gear? [This message has been edited by SN95 5.0 (edited 03-23-2001).]