Those running a T5

[Redstang69]

For all the guys running a T5 transmission, who has the 3.35 first gear and do you regret it over the 2.95?
The used pool to pick from is far far greater for the 3.35. On the flip side, all the new units are 2.95.
Hoping someone has some feedback
For more clarity, I'll have a 3.50 gear in rear and 17" wheels with 315/35R17 tires.

[Chopper]

Hello,

Do you have a specific rear end gearing you're planning on? What type of driving? Street/cruising? Track?

I have a T5 with the 2.95 1st gear and 3.55 rear gears, for street and cruising, I personally don't think I'd want a steeper first gear (350 HP 302 with an E303).

[Redstang69]

I'll be very similar to you Chopper, 351W .030 over and a cam, so no big HP numbers. Just street cruising and a 3.50 rear gear.

[mburger]

Originally, my Mk1 had a T5 out of the donor 1990 mustang. First gear was 3.35. In a cobra, it is useless running 3.50 gears in the rear. It’s like a truck gear lol. I rarely used it because you are practically red lining before getting halfway through the intersection. Here is a link to lmr.com which has the stock T5 specs by year if you are going the donor route. I have since replaced mine with a new upgraded T5 Z Spec from Mike Forte that will handle the torque of my 347 stroker.
I rarely tell anyone not to do something but as someone with experience running a T5 with 3.35 first and 3:55 rear gears, don’t do it.

https://lmr.com/products/mustang-t5-transmission-specs

[svassh]

Just swapped out my donor 90 Mustang T5 with 3.35 first gear for a new unit with 2.95 first gear. A noticeable improvement IMO. I have 3.27 rear end gears and even with those the 3.35 first gear ran out too fast.

[mburger]

svash, are you happy with fifth gear? My fifth gear is .63 and I need to be going at least 80 to use it without the feeling of a slight lugging in the engine. Dropping back into fourth puts me back at 3500 RPM and I don’t like that as a cruising rpm for sure. I find myself constantly going back-and-forth between fourth and fifth. Just curious about your experience as you’ve done the exact same thing I’ve just done.

[PG_Cobra]

My T5 is 3.35 1st gear with 0.83 5th gear, rear is 3.08. Really nice as a street car.
3.35 1st with 3.08 gives virtually the same overall ratio as 2.95 1st with a 3.55

[NC Cobra]

Mark - I’ve had the same experience with my car (302/T5/3:55). Around town its wonderful but on a freeway it just feels “out of sorts.”

[Jeff Kleiner]

I've built cars with both and all other things being equal I feel that the 2.95 first gear coupled with a 3.55 rear is pretty much ideal.

Jeff

[mburger]

I've built cars with both and all other things being equal I feel that the 2.95 first gear coupled with a 3.55 rear is pretty much ideal.

Jeff

Jeff,
Do you have any thoughts on an ideal fifth gear ratio? Again all else being equal.

[Jhinkemeyer]

Donor T5 with the 3.35 1st gear and 3.55 rear axle here.

Wish I had the $$ to go with something aftermarket with a 2.95. First gear is just annoying, can't even get down the driveway without making a **** ton of noise, or grabbing 2nd. Making a left hand turn, really requires you to shift before you are straightened out which can be annoying depending on circumstances.

Sometimes wonder if I should have left the 3.08 gears in the rear end lol.

[Blitzboy54]

Originally, my Mk1 had a T5 out of the donor 1990 mustang. First gear was 3.35. In a cobra, it is useless running 3.50 gears in the rear. It’s like a truck gear lol. I rarely used it because you are practically red lining before getting halfway through the intersection. Here is a link to lmr.com which has the stock T5 specs by year if you are going the donor route. I have since replaced mine with a new upgraded T5 Z Spec from Mike Forte that will handle the torque of my 347 stroker.
I rarely tell anyone not to do something but as someone with experience running a T5 with 3.35 first and 3:55 rear gears, don’t do it.

https://lmr.com/products/mustang-t5-transmission-specs

I wish I had read this a year ago. Same as you and I rarely if ever use first.

[FFR 3099]

I have a World Class T-5 with 2:95 first gear. I wouldn't recommend anything lower, you'll need to shift form 1-2 before you cross the intersection! The t-5 has a rather large gear spacing for 1-2 and a huge spacing from 4-5. I've tried a few different rear end ratios and I found 3:55 to be the best compromise for the top and bottom end, 1-2 gives a decent run-up and 4-5 allows me actually us 5th gear without lugging at lower road speeds.
:

[svassh]

svash, are you happy with fifth gear? My fifth gear is .63 and I need to be going at least 80 to use it without the feeling of a slight lugging in the engine. Dropping back into fourth puts me back at 3500 RPM and I don’t like that as a cruising rpm for sure. I find myself constantly going back-and-forth between fourth and fifth. Just curious about your experience as you’ve done the exact same thing I’ve just done.

I literally just got back from a AM drive and we have a farm road in and out of my subdivision the speed limit is 50mph. I was kind of marveling how well it runs in 5th gear at 50mph, 1300RPM with no lugging or issues just nice quiet cruise. Maybe its my Webers though they are pretty responsive.

The T5 I just installed a few weeks back: https://www.jegs.com/i/Ford-Performance/397/M-7003-Z/10002/-1

[Jeff Kleiner]

Jeff,
Do you have any thoughts on an ideal fifth gear ratio? Again all else being equal.

Mark,
It's all a mathematical exercise. Most engines that we use...barring a bone stock Mustang donor or a high strung stroker...seem to work well with an overall fifth gear reduction of somewhere in the neighborhood of 2.2 to 2.5.
Examples:
World class Mustang spec T-5 (.68 fifth) with a 3.55 rear=2.41:1
T-5z (.63 fifth) with a 3.55 rear=2.24:1

In contrast the W.C. T-5 with the typical Fox Mustang 2.73 rear axle ratio results in an overall fifth gear of 1.86:1---no wonder you really can't use fifth gear until 80mph+ with that combination!

On the other end I like to see a first gear overall of somewhere between 10:1 and 11:1
Examples:
World class Mustang spec T-5 (3.35 first) with a 3.55 rear=11.89:1 overall (most of us feel that this is too steep)
T-5z (2.95 first) with a 3.55 rear=10.47:1

Going back to that Fox Mustang comparison the W.C. T-5 with 3.35 first gear paired with the typical 2.73 rear end wound up being 9.69:1 which even in a 2,400 roadster is pretty soft.

Break out the calculators!

Jeff

[PG_Cobra]

Calculator out
3.35 1st with 3.08 rear = 10.32
0.83 5th with 3.08 rear = 2.56

[js65cobra]

I wish I had some of your guys ratios lol...

T5 WC, from `93, so the 3.35 ratio first gear....but... I have 4.10 rear. Sooo 13.735:1 (sad face)

I've been starting in 2nd sometimes to just ease the shifting amounts lol

Unfortunately didn't build the car back in 2001... but once the kids are out of daycare I hope to switch to the new T5 and probably look at switching out the rear gear as well.

[rich grsc]

I literally just got back from a AM drive and we have a farm road in and out of my subdivision the speed limit is 50mph. I was kind of marveling how well it runs in 5th gear at 50mph, 1300RPM with no lugging or issues just nice quiet cruise. Maybe its my Webers though they are pretty responsive.

The T5 I just installed a few weeks back: https://www.jegs.com/i/Ford-Performance/397/M-7003-Z/10002/-1
I run a 331 with Borla Stacks. I have the same driving experience with 3:55 rears, can drive all day in 5th around 13-1400rpms, no stumbles or lugging issues.

[mburger]

I literally just got back from a AM drive and we have a farm road in and out of my subdivision the speed limit is 50mph. I was kind of marveling how well it runs in 5th gear at 50mph, 1300RPM with no lugging or issues just nice quiet cruise. Maybe its my Webers though they are pretty responsive.

The T5 I just installed a few weeks back: https://www.jegs.com/i/Ford-Performance/397/M-7003-Z/10002/-1

I am running the same with slightly more torque capacity but Jegs likely rounded down?
Honestly, my only issue with the stock T5 was first gear. With about 85,000 miles on it it shifts like butter.

[mburger]

In contrast the W.C. T-5 with the typical Fox Mustang 2.73 rear axle ratio results in an overall fifth gear of 1.86:1---no wonder you really can't use fifth gear until 80mph+ with that combination!

Break out the calculators!

Jeff

My rear gears are 3:55. Henry noticed it as well in Texas. You feel like the 347 is happy at 3,500 and it is but not for cruising. Drop it into 5th and the RPMs drop ~1,400 down to ~2,000 with a bit of a lug until 2,500 hundred and she’s happy again. Including the Trooper with his instant on laser. Lol
One thing that I haven’t done and I simply haven’t had the time but is important, is to correctly set my “vacuum” advance at cruise. I also need to check the adjustment on my Wagner PCV valve to make sure it is switching circuits at the correct time going into cruise.

OR

I install Borla stacks and be done with it!:p

That’s excellent info Jeff thank you!

[FFR 3099]

Tremec has a good gear ratio calculator.

[rich grsc]

My rear gears are 3:55. Henry noticed it as well in Texas. You feel like the 347 is happy at 3,500 and it is but not for cruising. Drop it into 5th and the RPMs drop ~1,400 down to ~2,000 with a bit of a lug until 2,500 hundred and she’s happy again. Including the Trooper with his instant on laser. Lol
One thing that I haven’t done and I simply haven’t had the time but is important, is to correctly set my “vacuum” advance at cruise. I also need to check the adjustment on my Wagner PCV valve to make sure it is switching circuits at the correct time going into cruise.

OR

I install Borla stacks and be done with it!:p

That’s excellent info Jeff thank you!

Oh absolutely.. :o

[NC Cobra]

[QUOTE=mburger;496185]
One thing that I haven’t done and I simply haven’t had the time but is important, is to correctly set my “vacuum” advance at cruise. I also need to check the adjustment on my Wagner PCV valve to make sure it is switching circuits at the correct time going into cruise.


Hoping the group at large can share their knowledge with me on the comment Mark made above. I’ve done the math on my gearing and come out with a 2.33 ratio in 5th gear. (302 @ 320 hp / 315 torque - T5 @ .63 in 5th - 3:55 rear end ). According to conventional wisdom I should be fine but my experience in 5th gear has been much as Mark has described the engine seems to labor at about 1,200 @ 70 mph. I’ve had the carb re-jetted and tuned for my altitude; but I’ve not been happy with a lag when the secondaries open up and I’m beginning to think my two problems could be related based on Marks statement about vacuum advance. To be upfront, I have a basic knowledge of carbs (floats, idle etc) so if this seems to be a stupid question I apologize. Thanks in advance for any wisdom that can be imparted….

[Jeff Kleiner]

[QUOTE=mburger;496185]


Hoping the group at large can share their knowledge with me on the comment Mark made above. I’ve done the math on my gearing and come out with a 2.33 ratio in 5th gear. (302 @ 320 hp / 315 torque - T5 @ .63 in 5th - 3:55 rear end ). According to conventional wisdom I should be fine but my experience in 5th gear has been much as Mark has described the engine seems to labor at about 1,200 @ 70 mph. I’ve had the carb re-jetted and tuned for my altitude; but I’ve not been happy with a lag when the secondaries open up and I’m beginning to think my two problems could be related based on Marks statement about vacuum advance. To be upfront, I have a basic knowledge of carbs (floats, idle etc) so if this seems to be a stupid question I apologize. Thanks in advance for any wisdom that can be imparted….

That doesn't jive. If you have a 3.55 rear with a .63 fifth gear running the typical ~25.5" tall tire you should see around 2,000-2,100 RPM at 70 MPH, not 1,200 RPM. 1,200 RPM puts you around 45 MPH.

[rich grsc]

[QUOTE=NC Cobra;496283]

That doesn't jive. If you have a 3.55 rear with a .63 fifth gear running the typical ~25.5" tall tire you should see around 2,000-2,100 RPM at 70 MPH, not 1,200 RPM. 1,200 RPM puts you around 45 MPH.

Jeff, your math is spot on. 2100rpm gets me scooting along at 70mph

[mburger]

I posted a comment right below Jeff’s, but apparently it never posted but what I said was, yesterday I was out in the cobra and happened to verify that yes, at least in my car, 2000 RPMs gives me 70 mph in 5th.
I then addressed my earlier comments on vacuum advance.
In a nutshell, my slight lagging at cruise in 5th gear could be because I haven’t properly or completed my vacuum advance tuning as well as double checking my Wagner PCV valve set up.
I need to defer to you guys who have way more experience and knowledge than me to correct me if I’m off base. The last thing I want is to be posting inaccurate information.
I am expecting that with my vacuum advance and PCV valve properly set up, it likely would address the lagging I’m getting.

[GThompson]

I picked up a used ‘93 WC T5 (from a ‘93 Mustang Cobra, has a tapered roller bearing between the input & main shafts) years ago from Mark Ames that needed a new input shaft and, while rebuilding it and doing the S10 mod, I found it has a Sebring 5th gear (0.80). My Daytona has 3.27 final drive. I’ve not driven it more than 2 autocrosses and 3 parade laps at Watkins Glen but does anyone have any experience with similar gearing?

[Jeff Kleiner]

I picked up a used ‘93 WC T5 (from a ‘93 Mustang Cobra, has a tapered roller bearing between the input & main shafts) years ago from Mark Ames that needed a new input shaft and, while rebuilding it and doing the S10 mod, I found it has a Sebring 5th gear (0.80). My Daytona has 3.27 final drive. I’ve not driven it more than 2 autocrosses and 3 parade laps at Watkins Glen but does anyone have any experience with similar gearing?

No experience with that combination. The math says that you will have a first gear overall of 10.9, fifth overall of 2.6 and will be running 2,400 at 70 mph and 2,800 at 80. Might be a little busy at interstate speeds but you should have plenty of “go” without having to downshift to 4th.

Jeff

[Derald Rice]

I picked up a used ‘93 WC T5 (from a ‘93 Mustang Cobra, has a tapered roller bearing between the input & main shafts) years ago from Mark Ames that needed a new input shaft and, while rebuilding it and doing the S10 mod, I found it has a Sebring 5th gear (0.80). My Daytona has 3.27 final drive. I’ve not driven it more than 2 autocrosses and 3 parade laps at Watkins Glen but does anyone have any experience with similar gearing?

I have that combinationin both a T5 and a TKO600.......rear gear is 3.55

Going from 4th to 5th is not as huge of a RPM drop,

Cruising is around 2500- 2600 mark, but with the webers, that is right where they are "happy".

With a single 4bbl, I would consider a taller rear gear.

[GThompson]

Cruising is around 2500- 2600 mark, but with the webers, that is right where they are "happy".

Well I guess it’s good that I have Webers. :)

Thank you!

[bobl]

The key is how do you drive the car? High speed cruising, acceleration, twisty roads, slow traffic(parades and stuff). Based on my driving I made an unconventional choice. I switched from 3.55 gears to 4.10 gears. I have a 2.95 first gear and .63 fifth, plus a 500 HP, 7000 rpm 347. That change made the car really easy to drive. Not necessarily faster but a lot more user friendly based on my driving. I don't cruise at high speed or take long trips. very seldom over 70. The majority is back roads probably averaging no more than 50 mph. So the lower gears put it right in the sweet spot. It can lug down to 1000 rpm in 4th gear so it actually reduces how often you need to shift. The best improvement is low speed driving in traffic, parking lots, parades, etc. I can ease the clutch out in first gear and not have to use the throttle at all and the idle speed is slow enough that you are not having to push the clutch in frequently to slow down. 70 mph cruise is 2300 rpm and easily stay in 5th gear down to 40 mph. So, again I suggest to look at the big picture of how you will be using your car.

[john42]

The best improvement is low speed driving in traffic, parking lots, parades, etc. I can ease the clutch out in first gear and not have to use the throttle at all and the idle speed is slow enough that you are not having to push the clutch in frequently to slow down. 70 mph cruise is 2300 rpm and easily stay in 5th gear down to 40 mph. So, again I suggest to look at the big picture of how you will be using your car.

I can ease the clutch out in 1st as well for a slow roll start in a parking lot. However, due to my cam it wants to do the lurchy lurch dance. :-)

[Redstang69]

Thanks for all the good and detailed responses guys. Glad some of you are running setups similar to mine and have had experience with both gear sets.
I assume it's not really worth it to change out the gear set from the 3.35 to a 2.95.
I read you have to change the whole cluster, not sure if the mating gears to the main cluster have to be changed too or not.

[mburger]

Where are you located? I just took a peek at your profile but didn’t see a location but I could’ve just missed it.

[Railroad]

Thanks for all the good and detailed responses guys. Glad some of you are running setups similar to mine and have had experience with both gear sets.
I assume it's not really worth it to change out the gear set from the 3.35 to a 2.95.
I read you have to change the whole cluster, not sure if the mating gears to the main cluster have to be changed too or not.

I would consider changing rear gears. I have found if using Ford brand gears it maintains a good tooth pattern and using the pinion bearing shim sets the right back lash.

[rich grsc]

I would consider changing rear gears. I have found if using Ford brand gears it maintains a good tooth pattern and using the pinion bearing shim sets the right back lash.
He already has 3:55 rear gears

[mburger]

Redstang, if you were anywhere in the Florida area I was going to toss another idea at you.
Also I’m not sure where you are in the build process or if you are still in the planning phase.

[Railroad]

He already has 3:55 rear gears

For some reason, I thought he had a 3.35 1st gear T5.

What ever, I seem to get more wrong than right at my age.

[rich grsc]

For some reason, I thought he had a 3.35 1st gear T5.

What ever, I seem to get more wrong than right at my age.
No, you're correct about the transmission ratio, but you suggested change the rear gear ratio. Or did I misunderstand and you meant the transmission gears?

[Railroad]

No, you're correct about the transmission ratio, but you suggested change the rear gear ratio. Or did I misunderstand and you meant the transmission gears?

I may be seeing this wrong.
He has 3.55 rear gears times his 3.35 1st gear T-5 equates to 11.9 drive ratio.
With 3.08 gears and his 3.35 1st gear T-5, ratio would be 10.32.

Thus my, probably wrong logic, would be put in set of 3.08 rear gears.
I am ignoring his OD ratios, which may be more relevant to his issue.

[rich grsc]

Which gear do you spend the most time in, 1st or 5th and which is more important? Changing the rear affects all the transmission ratios

[Redstang69]

I'm located in East Central Ohio, so a pretty long ways from Florida.
I'm currently in mid-build. Hopefully I don't get flamed but I'm building a hurricane, not a FFR. Their kit comes with a Ford 9" so the rear gear would be simple to change, but I'd rather not. My mustang has a 3.00:1 rear end gear paired with a toploader and I'm not a fan. I know it's not an apples to apples comparison but around here there are a lot of hills, so 1st gear is really tall in it and I did not want that in the Cobra, esp. with a carb.
I haven't purchased the T5 yet. Since a used factory 2.95 first is next to impossible to find, I thought I might be able to broaden my search and use a 3.35, but it sounds like I just need to buy a new 2.95 and be done with it.

[mburger]

We aren’t the flaming kind here. Sure, there are discussions with different ideas and such, but no flaming.
Live your life! ;)
I would steer you to Mike Forte for your transmission purchase. He is the expert on all things Ford and highly respected not just in the FFR world but well beyond.

[rich grsc]

We aren’t the flaming kind here. Sure, there are discussions with different ideas and such, but no flaming.
Live your life! ;)
I would steer you to Mike Forte for your transmission purchase. He is the expert on all things Ford and highly respected not just in the FFR world but well beyond.
I hope you aren't referring to me? I wasn't, just trying to understand if the gear change was referring to the rearend or the transmission.

[Jeff Kleiner]

I'm located in East Central Ohio, so a pretty long ways from Florida.
I'm currently in mid-build. Hopefully I don't get flamed but I'm building a hurricane, not a FFR. Their kit comes with a Ford 9" so the rear gear would be simple to change, but I'd rather not. My mustang has a 3.00:1 rear end gear paired with a toploader and I'm not a fan. I know it's not an apples to apples comparison but around here there are a lot of hills, so 1st gear is really tall in it and I did not want that in the Cobra, esp. with a carb.
I haven't purchased the T5 yet. Since a used factory 2.95 first is next to impossible to find, I thought I might be able to broaden my search and use a 3.35, but it sounds like I just need to buy a new 2.95 and be done with it.

The toploader has either a 2.78 1st (wide ratio version) or a 2.32 1st (close ratio). Those are both much taller than either the 2.95 or 3.35 first gear in a T-5. What gear is in the 9 inch you will be using in the Hurricane? That will tell you which version of T-5 will best suit your needs and desires.

Jeff

[Redstang69]

Thanks guys. I knew you weren't the flaming kind, I stalked these forums for a while before pulling the trigger on a kit. This is a great group of people with a ton of knowledge.
Jeff, I have a 3.50 in the 9".
I've read a lot about Forte on here and at hurricane, he's very well respected and I'm sure I will be calling on him at some point.

[mburger]

I hope you aren't referring to me? I wasn't, just trying to understand if the gear change was referring to the rearend or the transmission.

???
I certainly wasn’t referring to you or anyone else for that matter.
I was just trying to let someone that might be new here know that we aren’t the kind to flame or pile on and that if we sometimes disagree on a topic we are all civil. I didn’t even mean to reference this thread. Certainly wasn’t my intent anyway. :D

[Railroad]

???
I certainly wasn’t referring to you or anyone else for that matter.
I was just trying to let someone that might be new here know that we aren’t the kind to flame or pile on and that if we sometimes disagree on a topic we are all civil. I didn’t even mean to reference this thread. Certainly wasn’t my intent anyway. :D

Just don't let it happen again!!! LOL

[mburger]

just don't let it happen again!!! Lol

:d :d