MikeH
Diamond Level Sponsor
I was thinking about that as I have the C4 that originally came on my 2.8. I also have the bellhousing that came on my T5. I want to look at that to see if it could be modded as well.
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What is really needed to adapt T-5 to 2.8 V-6?
- Thread starter mr.vman
- Start date
I was thinking about that as I have the C4 that originally came on my 2.8. I also have the bellhousing that came on my T5. I want to look at that to see if it could be modded as well.
MikeH
Diamond Level Sponsor
No the end of part 65 needs to be turned down to .590 to match the pilot bearing.
Part 60, the bearing retainer is what needs to be shortened to match the length of the retailer used on the 5.0 Mustang T5s.
I measured mine and it comes out to about 4.5" from the back (transmission side) of the large mounting flange (not the part that inserts into the tranny) to the end of the bearing tube.
More t-5 information
Reading throught a Ford Capri manual. The orginal Capri of the "70's" with the 2.8 V-6 had a rear axle ratio of; 3.22:1. The first gear ratio was, 3.65:1, of course with the four speed, fourth gear was direct, 1:1. The recommended T-5 first Gear for the conversion is around 3.35:1 with about a 4:1 rear axle (Alpine)? Is first gear a "stump puller granny"? I see that fith gear is a real overdrive. At 65 MPH and 75 MPH how many RPMs is the engine turning? I have the "SR-4" (Borg Warner I think), that came with the engine. This was out of the Mustang 11. Curious at to what ratio first gear the "SR-4" had, and what was the rear axle ratio of the Mustang 11 ? Would the so-called close ratio T-5 be a better choice because of first gear (less of a possible stump puller first gear)? With the close ratio T-5, RPM would be increased in 5 th gear over the conversion T-5 (more cruise RPM, less overdrive. This is why I am interested in the RPM's of the conversion T-5 at cruise speeds). No argument from me on any of this, just curious. I DO NOT WANT TO EXPERIMENT ON THIS! I am on this forum, because you have done this before. You have my attention on this, and I believe what you are writing. Once again thanks for the time and informatin.
Steve V.
Reading throught a Ford Capri manual. The orginal Capri of the "70's" with the 2.8 V-6 had a rear axle ratio of; 3.22:1. The first gear ratio was, 3.65:1, of course with the four speed, fourth gear was direct, 1:1. The recommended T-5 first Gear for the conversion is around 3.35:1 with about a 4:1 rear axle (Alpine)? Is first gear a "stump puller granny"? I see that fith gear is a real overdrive. At 65 MPH and 75 MPH how many RPMs is the engine turning? I have the "SR-4" (Borg Warner I think), that came with the engine. This was out of the Mustang 11. Curious at to what ratio first gear the "SR-4" had, and what was the rear axle ratio of the Mustang 11 ? Would the so-called close ratio T-5 be a better choice because of first gear (less of a possible stump puller first gear)? With the close ratio T-5, RPM would be increased in 5 th gear over the conversion T-5 (more cruise RPM, less overdrive. This is why I am interested in the RPM's of the conversion T-5 at cruise speeds). No argument from me on any of this, just curious. I DO NOT WANT TO EXPERIMENT ON THIS! I am on this forum, because you have done this before. You have my attention on this, and I believe what you are writing. Once again thanks for the time and informatin.
Steve V.
Barry
Diamond Level Sponsor
Steve,
Good questions, but the more important question is, what do you want your car to do best?
With a typical 5-speed OD 5th gear transmission, 1st through 4th (1.00:1) are the "go" gears and 5th gear is for cruising.
For drag racing, the RPM in 4th gear at the end of the quarter mile should be a few hundred RPM past peak power. Based on 6000 RPM / 90 MPH in the quarter mile, a rear axle ratio of 4.22 would be about right. With a 0.73 5th gear, 75 MPH would be about 3500 RPM.
For maximum speed, the RPM in 4th gear at maximum speed should be a few hundred RPM past peak power. Based on 6000 RPM / 120 MPH, a rear axle ratio of 3.22 would be about right. With a 0.73 5th gear, 75 MPH would be about 2600 RPM.
Everything else falls somewhere between those two performance extremes. Your car, your choice.
I think the 2.95 1st gear is "better" than the 3.35 for a V6 conversion, but the 2.95 1st gear T-5's are not available with the 7.85" input shaft.
Once YOU decide what YOU want YOUR car to do best, then YOU can use the information above to make YOUR choice.
Blanket statements about the "best" gearing are nonsense.
Barry
Alpine Bob
Donation Time
Barry,
Good to see you back on the Forum. How is your car coming along? Big show in Columbia in a couple of weeks, with a SOS before on Friday. Do you think you can make it?
Good to see you back on the Forum. How is your car coming along? Big show in Columbia in a couple of weeks, with a SOS before on Friday. Do you think you can make it?
Steve, for highway use, the 3.22 with a 5 speed is too much unless you are building an engine with a ton of torque (say a GM 3.4) or do not have much in the way of hills to contend with. I consider 3.55 the lowest you'd want to go for installations that use an overdrive 5th. Stump pulling lows are easier to live with than gutless 5th gears.
If your engine is larger than a 2.8, all I can say is "no comment".
Barry, using a 24" tire with 3.22 rear end and .73 5th, I get 2468 rpms at 75. Who has the defective calculator? I know I can't be wrong, maybe my calculator is junk.
Bill
If your engine is larger than a 2.8, all I can say is "no comment".
Barry, using a 24" tire with 3.22 rear end and .73 5th, I get 2468 rpms at 75. Who has the defective calculator? I know I can't be wrong, maybe my calculator is junk.
Bill
MikeH
Diamond Level Sponsor
That is my understanding. The bearing retainer for the 5.0 Mustang T5 is the correct length. And yes, the mounting flange needs to be turned down to fit the hole in the MII bellhousing.
http://www.jegs.com/i/JEGS/555/60110/10002/-1
Hi steve,
Bill is right. 3.22s are too high for good performance for the little 2.8 V6. The V6 Mutt II came with a set of 3.55s, which is the highest gear I recommend using. That gear is good all around, but not the best for autocrossing or drag racing. The 3.55s also are a bit too high for the overdrive, unless you want to cruise faster than 70 mph. The little 2.8 doesn´t have a lot of torque, so is lugging at 2,700/2,800 rpm, which is where it would be running with that gear.
The stock Alpine 3.89s or 4.22s, are a much better all around choice, because they work well in town and will cruise pretty relaxed in overdrive. The V6 runs better at 3,000 rpm. than at lower speeds. It gives better mileage too, at that rpm.
Jose
Bill is right. 3.22s are too high for good performance for the little 2.8 V6. The V6 Mutt II came with a set of 3.55s, which is the highest gear I recommend using. That gear is good all around, but not the best for autocrossing or drag racing. The 3.55s also are a bit too high for the overdrive, unless you want to cruise faster than 70 mph. The little 2.8 doesn´t have a lot of torque, so is lugging at 2,700/2,800 rpm, which is where it would be running with that gear.
The stock Alpine 3.89s or 4.22s, are a much better all around choice, because they work well in town and will cruise pretty relaxed in overdrive. The V6 runs better at 3,000 rpm. than at lower speeds. It gives better mileage too, at that rpm.
Jose
Barry
Diamond Level Sponsor
Bill,
Your calculations are not wrong, just a different assumption on tire size.
The Alpine came with 5.60 / 5.90 / 6.00-13 tires that were about 22.8" / 914 tire revolutions per mile and that is the number I used.
914 x 3.22 x 0.73 = 2155 engine revolutions per mile
= 2155 RPM @ 60 MPH
= 2685 RPM @ 75 MPH
= 2155 RPM @ 60 MPH
= 2685 RPM @ 75 MPH
A 24" tire would be about 850 tire revolutions per mile
850 x 3.22 x 0.73 = 1998 engine revolutions per mile
= 1998 RPM @ 60 MPH
= 2498 RPM @ 75 MPH
= 1998 RPM @ 60 MPH
= 2498 RPM @ 75 MPH
A difference of 30 RPM @ 75 MPH based on 24" tires is close enough for me.
I DID NOT RECOMMEND EITHER THE 3.22 OR 4.22 REAR AXLE RATIO. I said those were the extremes of the performance spectrum.
I say again, YOUR CAR, YOUR CHOICE. CHOOSE BASED ON WHAT YOU WANT YOUR CAR TO DO.
Barry
todd reid
Gold Level Sponsor
what is really needed...
Steve,
As an addendum to Barry's answer above, the other question is where does your engine make power? I think you will find that most of the popular mods discussed here (head work, big valves, cams, 4bbl carbs, etc) have the effect of pushing the power up the rpm band at the expense of low end torque. To overcome the lack of torque most people use a lower (numerically higher) rear.
My observation is that most T-5 installations involve some compromise - the ratios are so wide that it's easy to end up with either a stump puller first or a very tall 5th.
It's an equation with many variables, which is what makes it so interesting!
If possible drive a couple variations before comitting to one.
Steve,
As an addendum to Barry's answer above, the other question is where does your engine make power? I think you will find that most of the popular mods discussed here (head work, big valves, cams, 4bbl carbs, etc) have the effect of pushing the power up the rpm band at the expense of low end torque. To overcome the lack of torque most people use a lower (numerically higher) rear.
My observation is that most T-5 installations involve some compromise - the ratios are so wide that it's easy to end up with either a stump puller first or a very tall 5th.
It's an equation with many variables, which is what makes it so interesting!
If possible drive a couple variations before comitting to one.
Barry
Diamond Level Sponsor
Bill,
No change, I still plan on using 195/60-15 tires which are about 24".
I used the stock tire diameter because I thought it would apply to the most people. I should have included the tire info in my post, sorry about that.
Barry
Barry
Diamond Level Sponsor
Nick,
On the front, 15x6 wheels with an offset of +25 mm and a backspace of 4-1/2".
Still thinking about the back.
Barry
Looking at all the options on the T-5 swap. As I read through past posts, there is, or was an adapter, to install the shorter input shaft (V-8 T-5) into the 2.8. Is this adapter still available? If the adapter is available, where is it found, and any idea of price? Perhaps the adapter has "centering" problems in the pilot bushing/bearing hole? From what I have also read from past posts, the adapter needs longer metric flywheel bolts? I have started looking around for T-5's, not as inexpensive as I thought they would be. Prices are ranging from about, $450 plus shipping to $750+. These are for three star transmissions, what ever that means? The prices listed are for the "94" or newer T-5. I have also looked at the Summit cataloque at new t-5's. Once again, thanks for all the help and information.
Steve V.
Steve V.
I hope you don't mind me adding to this but, I would like to know if the 7.41" length input shaft is long enough to not need an adapter? If so is it possible to just swap out 4cyl cluster for a v8/v6 cluster??
http://www.tbtrans.com/t5_transmission.htm
http://www.therangerstation.com/tech_library/T5ID.htm
bob
http://www.tbtrans.com/t5_transmission.htm
http://www.therangerstation.com/tech_library/T5ID.htm
bob
Barry
Diamond Level Sponsor
Steve,
The "adapter" is needed if you use a V8 T-5 input shaft (7.18") with the V6 M-II bellhousing which needs a 7.85" input shaft.
The '94 and later Mustang T-5's have a 7.85" input shaft and the adapter is not needed.
The adapters were custom made and I have no idea where you would get one. Jose? Jim? The longer bolts are available.
Barry
Barry
Diamond Level Sponsor
Bob,
The 7.41" input shaft is 0.45" shorter than the correct length of 7.85". The very tip of the pilot bearing extension might reach the pilot bearing, but I would not take that approach. I have been in a car when the clutch assembly came apart and I don't want to repeat the experience.
Also, not sure if the splines for the clutch disc would be in the right location.
A T-5 input shaft is made to be used with the matching cluster gear, so a I-4 7.41" input shaft would only match up with I-4 clusters. Some of the V6 and V8 T-5's had the same 3.35 1st gear, so MAYBE those input shafts could be swapped.
Jim E
Donation Time
I do not know who can supply a pilot bearing adaptor. I do think it is posible the Ranger/Bronco II flywheel will work with the V8 T5 and no bearing adaptor. The reason I say this is the center of the R/BII flywheel sticks back toward the transmission about the same as the adaptor bolted to a MII F/W. At least it sure look near the same to me. This is the center part that has to be turned out to use the R/BII flywheel and a 3.8 T5. Guess the trick would be to know the input shaft length of the transmissions used behind the 2.8 and 2.9 in the R/BII applications.