gears didn't do S**T!

da89cup · 07-24-2001, 09:10 PM

I went from 2.73s to 4.10s & didn't even lose a tenth. My trap speed was 96.97mph, & my best 60' time was 2.196

------------------
89 coupe, 351W, 351W heads, 30lb injectors, 190lph pump, 80 maf, 70 tb, ? cam, cobra upper, gt 40 lower(14.6at95mph)

SlowStang2 · 07-24-2001, 09:15 PM

Same here too. I went from 3.08s to 3.55s and I not only didnt go faster, I lost 1 tenth!!! Now I have been playing with shift points and launches and I have no improvement anywhere. (I only said that because that is what people will suggest)

------------------
94' Stang GT Convertible --Cobra upper&lower, Mac cold air w/K&N, BBK equal length shorties, BBK offroad H-pipe, American Thunder cat-back, BBK T/B 65mm, 24lb injectors, Pro-77mm MAM, pulleys, aluminum driveshaft, 3.55s 14.4@100. (Sad, i know. i have stock heads)

da89cup · 07-24-2001, 11:18 PM

With that mph, I think you should be in the 13s. What are your 60' times.

Red514LX · 07-24-2001, 11:46 PM

4.10s are definitely not the end-all for gears. I think the best way to pick a gear is to

(1) Get your car dynoed and tuned

(2) Talk with the tuner about optimum shift points based on the dyno curve

(3) Go to the track and experiment with launch/shift rpms. Also, note at what rpm you finish the 1/4

(4) Based on this information -- go to a speed shop and talk with a tech guy and you both decide which gear is the best for your car.

I think 302s do well with a 4.10 gear because it helps them get out of the hole quicker. With a 351W, you have more bottom end and midrange torque -- I think such a steep gear as a 4.10 is perhaps not as neccesary.

Don't worry about things as they are now, though. From looking at your combo, it seems to me like you have a very mild 351W. A gear swap isn't going to make a HUGE difference at this power level.

I want to let you know that I have a friend with a 351W and this guy runs low 10s -- all motor. I tell you this because I want you to know the potential of the engine you have in your coupe. Of course, his car is carburated, runs 118 octane fuel, has a monster cam, etc. etc. He does drive it to work and whatnot but I wouldn't want to drive it every day.

Save up some $$ though and go through the motor and do it right. Even with EFI, there's no reason not to run 118-125mph on motor with a semi-hot street/strip 351W using off the shelf parts.

Good Luck!!

------------------
Jeff Kane
1990 LX Mustang Coupe

429AL · 07-25-2001, 12:16 AM

96 OR 97 mph should be low 14`s. I went 13.91 @101 mph and i had aod and 3.73`s. that was in my 85

------------------
Stock 89 GT with 147000 miles,but not for long. Now with 3.73`s, soon 306 from 85 install.

LX NCH 50 · 07-25-2001, 12:18 AM

I have 3.73, mild engine work on my notch and ran a 13.7@101.5 2.5 60' time... My electric fan crapped out on me so I was running at 240 degrees, I bet I could have pulled a 13.4-5 if I was running under 200 degrees.

richie · 07-25-2001, 01:01 AM

I think lower gears are overrated unless you have the right suspension and tire upgrades.I am saving up for a 351 which I want to get at least 400hp out of .I have 3.73's that I hate and when I get my 351 I'm going to change them out for a higher gear.351's have so much torque that they don't need a lower gear.

wrathchild · 07-25-2001, 02:07 AM

Not saying you dont know how to drive but, its all in the way you drive your car. With new gears you almost have to learn how to drive your car again. I have just recently broke into the 13's. I didnt have the money to build my car so i was just trying different things everytime at the track and while i was i was also learning to drive it better. Started with 14.6's then got to 14.3's, then 14.1's and now 13.9's.

------------------
90 GT 150k on the motor never had the valve covers off, 1 5/8" headers, x-pipe, 2chamber flowmaster,fms aluminum ds, 3.55, best time on 245/45/17 2.08 60', 13.906 @ 98.98

smokedchevy · 07-25-2001, 02:30 AM

I'm assuming your running street tires. Whether you have 2:73s or 4:10's you're going to burn out the same anyway. If you were running slicks , I gurantee you'd see a major improvement. The 4:10's would launch a lot harder than the bogging 2:73's. I'm surprised you didn't run slower, 4:10's would make you lose traction even more. Get your tires to stick and you'll see why everyone loves 4:10 gears. I bet you'll break or come close to 13's with 26x10" slicks.

------------------
92 GT, 4:10 gears, centerforce clutch, 6# powerdyne blower, bbk h-pipe, flowmasters

Dark Knight · 07-25-2001, 03:20 PM

gears will not increase the MPH at the finish..only more HP will do that..
are you running a stick or an auto? either way, it takes practice..

------------------
84 convt,'95 302,AFR's, performer
3.55's, underdrives BBK shorties
stock cam, 1.7's
13.85@102.5
and a '68 stang that WAS nasty ;-)

BlackFly · 07-25-2001, 10:01 PM

you didnt mention whether your car is auto or stick , does your car not feel faster? it really should feel stronger, im not a big fan of quarter mile stuff, but if you are , driving is a real big part. traction is a huge part to getting down the track in a hurry. do you not have a ton of wheel spin now? like about a hundred feet?

90dpscoupe · 07-25-2001, 10:34 PM

Wrathchild, i agree with you, and i did the same 14.6 then worked my way down, do you have your swaybar off wrath?

well anyway this guy has to get the lauch down with new gears, but i ran 13.9 with a 2.0 60' the 1.9 was a missed shift run.

With 4.10 gears, i would have probaly spun all the way to 4th, but my friends 85 coupe launches wicked on some 4.10's and e.t. streets.

------------------
90 lx coupe: 175k miles, steeda water pump pully, hurst shifter, Mac cold air fenderwell, accel supercoil, ADS chip, aluminum D/S, Black magic fan, 3.27grs.
Best time: 13.9116(on 225/60/15 firehawks)
Best mph: 98.17
Best 60': 1.9607

next mods: subframes, mac h-pipe

da89cup · 07-26-2001, 01:18 AM

The car feels a lot stronger, but it's still slow on the quarter mile. I don't get it, if my 60' time is bad, the car pulls awesome on 2nd, 3rd, & 4th, so why the hell is it so slow, and I don't spin for a 100'. I spin on 1st but that's it, then on 2nd, the tires chirp & I'm gone.

------------------
89 coupe, 351W, 351W heads, 30lb injectors, 190lph pump, 80 maf, 70 tb, ? cam, cobra upper, gt 40 lower(14.6at95mph)

wrathchild · 07-26-2001, 01:39 AM

No i dont have it off now but, When i ran my first 14.1, i was unaware my swaybar to a-arm link was snapped in 2. Wondered where that clunking noise was coming from. I like to carve some corers also so having the swaybar off is kinda no go. My girlfriend also likes to drive my car and i would like it to return in one piece when she brings it back. I know it would help though. I am just gonna buy some ET streets. Gonna need em too. I am buying heads, intake, cam and all the good stuff next month.

------------------
90 GT 150k on the motor never had the valve covers off, 1 5/8" headers, x-pipe, 2chamber flowmaster,fms aluminum ds, 3.55, best time on 245/45/17 2.08 60', 13.906 @ 98.98

Unit 5302 · 07-26-2001, 01:56 AM

You know, I've heard the "gears don't add mph" for a while now.

I'd like an explanation for that. Given a set amount of distance how fast a car is travelling at the end will be directly related to it's acceleration while covering the distance. Take a 60ft time. Are you saying that with gears running a 1.8 60ft you'll be travelling the same speed as you would with 2.73's running a 2.2 60ft? That's not possible, unless the 2.73's are superior for accleration once the car is moving. If the 2.73's are superior for accelerating, all a person should do is figure out how to launch it.

Lower gears absolutely MUST add trap speed if they allow for better acceleration. They do add horsepower in a non direct fashion. They allow you to stay in your powerband, effectively increasing the average horsepower that you are accelerating with. Accelerating faster over a given distance means a higher velocity at the end of the set distance, in this case, the 1/4 mile.

[This message has been edited by Unit 5302 (edited 07-26-2001).]

shovelnose · 07-26-2001, 02:33 AM

I have to agree with Unit 5302. I ran 106 mph with 3.73 and 101 with 3.08 on street tires also .9 sec faster.

They were different cars, similar weight and the same drive train,

------------------
82 Mercury Capri 302.
Comp. Cams
Tremec 3550
3.73's
12.8@106 N/AKevin's Capri

Skyman · 07-26-2001, 03:05 AM

What needs to be addressed here is your motor combo not your gears. Everything is completely mis matched.

30lb injectors on a car trapping 95mph? Your making less hp than most stock 5.0's and your running 11lb's more of injectors.

Your TB is too big. Whats your compression? Whats your timing? Cam is unknown, I dont know how the cobra upper matches to a gt40lower. But your car is really screwed up. A coupe wtih a T-5 should trap about 96+mph bone stock.

Skyler

------------------
-1989 Saleen Mustang #406-
TFS TW Heads, E-303, Edelbrock intake, 70mm TB, 73mm MAF, 24lb injectors, 1 5/8 shorties, Off Road H, 3 Chamber flows, Jaz Race seats, Back seat removed, sub-frames, Roll Cage, and a 80 shot of N20.
12.54@107.4 Motor
1.69 60'

Unit 5302 · 07-26-2001, 06:24 PM

The Cobra, GT-40, and the Explorer all use the exact same GT-40 lower manifold. The only thing different is the upper, and as far as flow volume, they are almost identical.

You are running a combination very similar to the 1995 Cobra R. You should be deep into the 13's. I also agree your injectors being too big, but the 70mm T/B is okay since you are running a 351. What are the 351W heads off of? If they came off some crappy old 351 that is one of your problems.

Sell the Cobra/GT-40 setup, get a TFS manifold to replace it. Have the heads worked, or get some good aftermarket units. Add an aggressive cam combination.

If you are just trying to get by, change the cam so you know what's in it, and have the heads worked. The GT-40 setup on the Cobra R was restictive on that engine as well.

07-24-2001, 09:10 PM	#1
da89cup Registered Member Join Date: Feb 2001 Location: edmonton, alberta, canada Posts: 55	gears didn't do ST!** I went from 2.73s to 4.10s & didn't even lose a tenth. My trap speed was 96.97mph, & my best 60' time was 2.196 ------------------ 89 coupe, 351W, 351W heads, 30lb injectors, 190lph pump, 80 maf, 70 tb, ? cam, cobra upper, gt 40 lower(14.6at95mph)

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
gears?	Spyder1914	Small Ponies	4	01-08-2003 02:23 PM
Gears Gears Gears!!!!	COBRAon18s	Modular Madness	20	05-13-2002 04:44 PM
how can you tell what size gears you have?	Kamaro Killer	Windsor Power	7	04-03-2002 02:55 PM
Gears, need help!!!!	Edgar Negron	Windsor Power	3	05-27-2001 03:10 PM
Gears Gears Gears	Skyman	Windsor Power	6	03-11-2001 11:39 PM

07-24-2001, 09:15 PM	#2
SlowStang2 Registered Member Join Date: May 2001 Location: Stuart, FL, US Posts: 147	Same here too. I went from 3.08s to 3.55s and I not only didnt go faster, I lost 1 tenth!!! Now I have been playing with shift points and launches and I have no improvement anywhere. (I only said that because that is what people will suggest) ------------------ 94' Stang GT Convertible --Cobra upper&lower, Mac cold air w/K&N, BBK equal length shorties, BBK offroad H-pipe, American Thunder cat-back, BBK T/B 65mm, 24lb injectors, Pro-77mm MAM, pulleys, aluminum driveshaft, 3.55s 14.4@100. (Sad, i know. i have stock heads)

07-24-2001, 11:18 PM	#3
da89cup Registered Member Join Date: Feb 2001 Location: edmonton, alberta, canada Posts: 55	With that mph, I think you should be in the 13s. What are your 60' times.

07-24-2001, 11:46 PM	#4
Red514LX Registered Member Join Date: Mar 1999 Location: Detroit, MI Posts: 119	4.10s are definitely not the end-all for gears. I think the best way to pick a gear is to (1) Get your car dynoed and tuned (2) Talk with the tuner about optimum shift points based on the dyno curve (3) Go to the track and experiment with launch/shift rpms. Also, note at what rpm you finish the 1/4 (4) Based on this information -- go to a speed shop and talk with a tech guy and you both decide which gear is the best for your car. I think 302s do well with a 4.10 gear because it helps them get out of the hole quicker. With a 351W, you have more bottom end and midrange torque -- I think such a steep gear as a 4.10 is perhaps not as neccesary. Don't worry about things as they are now, though. From looking at your combo, it seems to me like you have a very mild 351W. A gear swap isn't going to make a HUGE difference at this power level. I want to let you know that I have a friend with a 351W and this guy runs low 10s -- all motor. I tell you this because I want you to know the potential of the engine you have in your coupe. Of course, his car is carburated, runs 118 octane fuel, has a monster cam, etc. etc. He does drive it to work and whatnot but I wouldn't want to drive it every day. Save up some $$ though and go through the motor and do it right. Even with EFI, there's no reason not to run 118-125mph on motor with a semi-hot street/strip 351W using off the shelf parts. Good Luck!! ------------------ Jeff Kane 1990 LX Mustang Coupe

07-25-2001, 12:16 AM	#5
429AL Registered Member Join Date: May 2001 Location: Tacoma,wa,usa Posts: 41	96 OR 97 mph should be low 14`s. I went 13.91 @101 mph and i had aod and 3.73`s. that was in my 85 ------------------ Stock 89 GT with 147000 miles,but not for long. Now with 3.73`s, soon 306 from 85 install.

07-25-2001, 12:18 AM	#6
LX NCH 50 Registered Member Join Date: Jul 2001 Location: Schaumburg, IL, USA Posts: 31	I have 3.73, mild engine work on my notch and ran a 13.7@101.5 2.5 60' time... My electric fan crapped out on me so I was running at 240 degrees, I bet I could have pulled a 13.4-5 if I was running under 200 degrees.

07-25-2001, 01:01 AM	#7
richie Registered Member Join Date: Apr 2001 Posts: 47	I think lower gears are overrated unless you have the right suspension and tire upgrades.I am saving up for a 351 which I want to get at least 400hp out of .I have 3.73's that I hate and when I get my 351 I'm going to change them out for a higher gear.351's have so much torque that they don't need a lower gear.

07-25-2001, 02:07 AM	#8
wrathchild Registered Member Join Date: Jul 2001 Location: altoona pa usa Posts: 49	Not saying you dont know how to drive but, its all in the way you drive your car. With new gears you almost have to learn how to drive your car again. I have just recently broke into the 13's. I didnt have the money to build my car so i was just trying different things everytime at the track and while i was i was also learning to drive it better. Started with 14.6's then got to 14.3's, then 14.1's and now 13.9's. ------------------ 90 GT 150k on the motor never had the valve covers off, 1 5/8" headers, x-pipe, 2chamber flowmaster,fms aluminum ds, 3.55, best time on 245/45/17 2.08 60', 13.906 @ 98.98

07-25-2001, 02:30 AM	#9
smokedchevy Registered Member Join Date: Jun 2000 Location: ventura,CA Posts: 438	I'm assuming your running street tires. Whether you have 2:73s or 4:10's you're going to burn out the same anyway. If you were running slicks , I gurantee you'd see a major improvement. The 4:10's would launch a lot harder than the bogging 2:73's. I'm surprised you didn't run slower, 4:10's would make you lose traction even more. Get your tires to stick and you'll see why everyone loves 4:10 gears. I bet you'll break or come close to 13's with 26x10" slicks. ------------------ 92 GT, 4:10 gears, centerforce clutch, 6# powerdyne blower, bbk h-pipe, flowmasters

07-25-2001, 03:20 PM	#10
Dark Knight Registered Member Join Date: Oct 1998 Location: Az Posts: 854	gears will not increase the MPH at the finish..only more HP will do that.. are you running a stick or an auto? either way, it takes practice.. ------------------ 84 convt,'95 302,AFR's, performer 3.55's, underdrives BBK shorties stock cam, 1.7's 13.85@102.5 and a '68 stang that WAS nasty ;-)

07-25-2001, 10:01 PM	#11
BlackFly Registered Member Join Date: Feb 2001 Location: winnipeg , manitoba , canada Posts: 83	you didnt mention whether your car is auto or stick , does your car not feel faster? it really should feel stronger, im not a big fan of quarter mile stuff, but if you are , driving is a real big part. traction is a huge part to getting down the track in a hurry. do you not have a ton of wheel spin now? like about a hundred feet?

07-25-2001, 10:34 PM	#12
90dpscoupe Registered Member Join Date: Jun 2000 Location: sanantonio, Tx, usa Posts: 1,407	Wrathchild, i agree with you, and i did the same 14.6 then worked my way down, do you have your swaybar off wrath? well anyway this guy has to get the lauch down with new gears, but i ran 13.9 with a 2.0 60' the 1.9 was a missed shift run. With 4.10 gears, i would have probaly spun all the way to 4th, but my friends 85 coupe launches wicked on some 4.10's and e.t. streets. ------------------ 90 lx coupe: 175k miles, steeda water pump pully, hurst shifter, Mac cold air fenderwell, accel supercoil, ADS chip, aluminum D/S, Black magic fan, 3.27grs. Best time: 13.9116(on 225/60/15 firehawks) Best mph: 98.17 Best 60': 1.9607 next mods: subframes, mac h-pipe

07-26-2001, 01:18 AM	#13
da89cup Registered Member Join Date: Feb 2001 Location: edmonton, alberta, canada Posts: 55	The car feels a lot stronger, but it's still slow on the quarter mile. I don't get it, if my 60' time is bad, the car pulls awesome on 2nd, 3rd, & 4th, so why the hell is it so slow, and I don't spin for a 100'. I spin on 1st but that's it, then on 2nd, the tires chirp & I'm gone. ------------------ 89 coupe, 351W, 351W heads, 30lb injectors, 190lph pump, 80 maf, 70 tb, ? cam, cobra upper, gt 40 lower(14.6at95mph)

07-26-2001, 01:39 AM	#14
wrathchild Registered Member Join Date: Jul 2001 Location: altoona pa usa Posts: 49	No i dont have it off now but, When i ran my first 14.1, i was unaware my swaybar to a-arm link was snapped in 2. Wondered where that clunking noise was coming from. I like to carve some corers also so having the swaybar off is kinda no go. My girlfriend also likes to drive my car and i would like it to return in one piece when she brings it back. I know it would help though. I am just gonna buy some ET streets. Gonna need em too. I am buying heads, intake, cam and all the good stuff next month. ------------------ 90 GT 150k on the motor never had the valve covers off, 1 5/8" headers, x-pipe, 2chamber flowmaster,fms aluminum ds, 3.55, best time on 245/45/17 2.08 60', 13.906 @ 98.98

07-26-2001, 01:56 AM	#15
Unit 5302 Registered Member Join Date: May 1999 Posts: 5,246	You know, I've heard the "gears don't add mph" for a while now. I'd like an explanation for that. Given a set amount of distance how fast a car is travelling at the end will be directly related to it's acceleration while covering the distance. Take a 60ft time. Are you saying that with gears running a 1.8 60ft you'll be travelling the same speed as you would with 2.73's running a 2.2 60ft? That's not possible, unless the 2.73's are superior for accleration once the car is moving. If the 2.73's are superior for accelerating, all a person should do is figure out how to launch it. Lower gears absolutely MUST add trap speed if they allow for better acceleration. They do add horsepower in a non direct fashion. They allow you to stay in your powerband, effectively increasing the average horsepower that you are accelerating with. Accelerating faster over a given distance means a higher velocity at the end of the set distance, in this case, the 1/4 mile. [This message has been edited by Unit 5302 (edited 07-26-2001).]

07-26-2001, 02:33 AM	#16
shovelnose Registered Member Join Date: Oct 2000 Location: Ontario, Canada Posts: 234	I have to agree with Unit 5302. I ran 106 mph with 3.73 and 101 with 3.08 on street tires also .9 sec faster. They were different cars, similar weight and the same drive train, ------------------ 82 Mercury Capri 302. Comp. Cams Tremec 3550 3.73's 12.8@106 N/AKevin's Capri

07-26-2001, 03:05 AM	#17
Skyman I need 110mph Trap Speed! Join Date: Feb 1999 Location: So, CA Posts: 4,315	What needs to be addressed here is your motor combo not your gears. Everything is completely mis matched. 30lb injectors on a car trapping 95mph? Your making less hp than most stock 5.0's and your running 11lb's more of injectors. Your TB is too big. Whats your compression? Whats your timing? Cam is unknown, I dont know how the cobra upper matches to a gt40lower. But your car is really screwed up. A coupe wtih a T-5 should trap about 96+mph bone stock. Skyler ------------------ -1989 Saleen Mustang #406- TFS TW Heads, E-303, Edelbrock intake, 70mm TB, 73mm MAF, 24lb injectors, 1 5/8 shorties, Off Road H, 3 Chamber flows, Jaz Race seats, Back seat removed, sub-frames, Roll Cage, and a 80 shot of N20. 12.54@107.4 Motor 1.69 60'

07-26-2001, 06:24 PM	#18
Unit 5302 Registered Member Join Date: May 1999 Posts: 5,246	The Cobra, GT-40, and the Explorer all use the exact same GT-40 lower manifold. The only thing different is the upper, and as far as flow volume, they are almost identical. You are running a combination very similar to the 1995 Cobra R. You should be deep into the 13's. I also agree your injectors being too big, but the 70mm T/B is okay since you are running a 351. What are the 351W heads off of? If they came off some crappy old 351 that is one of your problems. Sell the Cobra/GT-40 setup, get a TFS manifold to replace it. Have the heads worked, or get some good aftermarket units. Add an aggressive cam combination. If you are just trying to get by, change the cam so you know what's in it, and have the heads worked. The GT-40 setup on the Cobra R was restictive on that engine as well.