Close



Results 1 to 13 of 13
  1. #1

    Default Who has a T5Z with 3.73 gears

    I am now debating on getting a T5Z partly because the car came with 3.73 gears which I like. but first gear is pretty useless right now.

    So, who has a 2.95 first gear with 3.73's and how do you like it? It will pick up 5 mph in first gear 41.7 vs 36.7 @ 6k.
    and in 5th gear 65 mph @ 2k vs 60 mph @2k in 5th which is nice as well.

    Was it a worthy switch?

  2. #2

    Default

    I have a plain old stock original 1984 T5 which is a 2.95 as all the 1983-84 T5s were and a 3:73 8.8 out of a '92 LX (EDIT...I PUT the 3:73 in it myself. It's a FRPP gear set and I also bought it new). It seems very well matched and I do like it a lot. It does not drone or seem unwieldy whatsoever on the highway. From the first drive, I was happy I did not do a 3:55. Seems like it should have come that way. It sounds faster if I can say I have a T5Z though, LOL.
    Last edited by homer302; 01-04-2019 at 07:48 PM.

  3. #3

    Default

    Thanks Does the 83 trans have the .63 overdrive too?

  4. #4
    Moderator wraithracing's Avatar
    Join Date
    Jun 2010
    Location
    Grand Junction, CO/RR TX
    Posts
    14,206

    Default

    Quote Originally Posted by toddf View Post
    Thanks Does the 83 trans have the .63 overdrive too?
    If my memory is correct, I believe the 83/84 T5 5th gear is 0.72 Overdrive.

    I believe all the 85-93 T5 5th gears are 0.68 Overdrive.
    ​Trey

    "I Don't build it hoping for your approval! I built it because it meets mine!"

    "I've spent most of my money on Mustangs, racing, and women... the rest I just wasted."

    Mustangs Past: Too many to remember!
    Current Mustangs:
    1969 Mach 1
    1979 Pace Car now 5.0/5 speed
    1982 GT Stalled RestoModification
    1984 SVO Still Waiting Restoration
    1986 GT Under going Wide Body Conversion Currently

    Current Capris:
    1981 Capri Roller
    1981 Capri Black Magic Roller Basket Case
    1982 Capri RS 5.0/4spd T-top Full Restoration Stalled in TX
    1984 Capri RS T-top Roller
    1983-84 Gloy Racing Trans Am/IMSA Body Parts

  5. #5
    FEP Senior Member
    Join Date
    May 2016
    Location
    Lake City Pa 16423
    Posts
    510

    Default

    As long as you don't want to take it to the track, that set up is fine. If you want to drag race it, the 2.95 will kill your 60 foot times and most likely bog off of the starting line. It is pretty worthless at the track.

  6. #6

    Default

    Quote Originally Posted by dynodon64 View Post
    As long as you don't want to take it to the track, that set up is fine. If you want to drag race it, the 2.95 will kill your 60 foot times and most likely bog off of the starting line. It is pretty worthless at the track.
    Not trying to argue because I have no facts to back anything up. I just am interested in continuing the conversation. Every article I have ever read in a magazine says drag racers do the exact opposite. They pull a 3:35 out and change the ratio to a 2.95. The rear gear ratio will determine what happens on the starting line. If you are talking a car with a stock rear gear, I wouldn't take that to the track anyway if I was interested in fast times. The Ford Performance 6-speed they sell for $3,200 just for the transmission has a 2.97 first gear just for one example.

  7. #7

    Default

    A t5 with 3.27 gears is the same ratio as a 2.95 with3.73.
    With over 400 hp bogging won’t be an issue

  8. #8
    FEP Super Member mmb617's Avatar
    Join Date
    May 2005
    Location
    Altoona, PA
    Posts
    4,249

    Default

    Quote Originally Posted by toddf View Post
    With over 400 hp bogging won’t be an issue
    No, it won't.

    I always thought I would be better off with the 2.95 first gear when I was racing as first gear was too short with the 3.35 and my 3.73 rear gear. I certainly wouldn't worry about bog as I usually launched at no more than 3900 to control tire spin. Any potential bog could be cured with more launch rpm.

    I will say that T5's aren't particularly fond of being behind 400 hp if you run it hard though. It got to the point that I think I could rebuild one in my sleep.
    408/T5/3.73's

    We're not fast racers, we're more what's known as half fast racers.

  9. #9
    FEP Super Member erratic50's Avatar
    Join Date
    Dec 2016
    Location
    Nebraska
    Posts
    4,575

    Default

    I don’t have 3.73’s but have been around them.

    Quick ratio math:
    3.35 * 3.73 = 12.4955
    2.95 * 3.73 = 11.0035

    As mentioned — same ratio as a 3.27 with a 3.35

    That all being said I’ve observed that the rate that you release the clutch at and the launch RPM have tremendous influence on 60’ also. Simple rev it up and dump it gives too little time for any weight transfer and the result can often be ..... well .... a smoke show.

    Hotrod and Car Craft and even Muscle Mustangs and Fast Fords used to provide a formula for selecting the ratio. Weight balance front/rear, flywheel weight, vehicle weight, engine torque @launch RPM, horsepower @ launch RPM, etc.

    Street/strip is a MUCH different game than only strip. Strip only has you throwing in light flywheels and choosing launch RPM as peak torque point or slightly above, etc.

    I can’t fibd their formula now. What I remember is at around 400 HP and 400 ft lbs in a 3000 lb car with frontal weight bias, the launch ratio range often well tolerated is suggested as not more than 12:1 and not less than 10.5.

    It’s all averages stuff.... but you probably need to either add power or run a steeper rear gear with a 2.95. Around 3.90.

    Also the question is what ET and MPH are you after and what’s the RPM range of the motor?

    For a car that can run high 9’s you need to break 130 mph and at 1:1 (drive on auto, 4th on stick). Involving an OD is too much of % drop. No 1/4 blasts with 5th if you like your Z.

    Unless im missing something things sorta point to a short tire with a 3.73 and a 2.95 or a moderate tire with a 3.90 or a tall tire with a 4.10.

    Seems like 2.95 with a 3.90 rear gear is the ticket at 400/40. Give a good window

    Gear simulators are a lot better than the work of a bad gear swap.

    With a very broad torque curve and RPM range comes things like targeting 1 shift only or two shifts only too. No “right” answer if you can get something to run the numbers consistently.

    If you can spin the tire and you can bog the motor clutch application becomes the variable and a good 60’ is possible. But clutches are a wearable that changes as it wears so they make things less predictable when relied upon heavily

    3.90 and 2.95 is what I plan to do to my 86GT.

    Think of 5th in a Z as 6th in a trans that has no 5th— it is a long ways from 1:1

  10. #10
    FEP Senior Member
    Join Date
    May 2016
    Location
    Lake City Pa 16423
    Posts
    510

    Default

    If your running street tires at the track, it doesn't matter what gears you use, it's a mute point with my comment earlier. If you run slicks and a 2.95 first gear and any gear below a 4.10, you will have a problem with your 60 foot times as well as a potential problem of bogging. That's also running a 26 inch tall slick. @
    and 28 inch slicks will make it even worst. I use to run 3.27 first gear, 3.73 rear gears and 28 inch M/T slicks and pull 1.4 60 foot times at a launch of 6k rpm, and go through the traps @132mph in the mid 10's with 3400 pound car. Anyone I ever saw run a 2.95 first gear could not pull a 60 time to save their life. They bought the 2.95 because it could handle more torque, but they then would switch back because it would not get off the starting line.
    Last edited by dynodon64; 01-07-2019 at 05:16 PM. Reason: missed typed

  11. #11

    Default

    Holy Snikies! You had to have well north of 600 HP to get a 132 MPH speed. That thing must've been a beast for sure. Like most mods, it matters what your intentions for the car are and whether you want to drive it on the street etc. You're not daily driving a pushrod 5.0 with 600+ HP very far but it would make a @#$ of a race car.

  12. #12

    Default

    Quote Originally Posted by toddf View Post
    I am now debating on getting a T5Z partly because the car came with 3.73 gears which I like. but first gear is pretty useless right now.
    Talk about useless, I run a 3.35/4.10 combo with 255/50/16 tires. It screws with people when you stab it about 5 MPH and it lights up like on ice...LOL
    84 Cougar, 90 HO with 700DP, Edelbrock RPM intake, 1.7 RRs, shorty's and SS exh, T-5, KC clutch, Hurst pro billet, line loc, 8.8, 4.10s, suspension mods....blah, blah,blah.

    71 Comet, 289, Liberty TL, 9", 6.00s, 11.9x @ 112.... blah, blah, blah.

  13. #13
    FEP Senior Member
    Join Date
    May 2016
    Location
    Lake City Pa 16423
    Posts
    510

    Default

    My car had over 800 hp at the crank and put down 700 at the wheels on a Dynojet. It was a 347 with a Vortech Ys trim pushing 18 psi of boost. The car was stripped down and sold as parts. 94 model.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •