Optimum gearing ideas

[Young Ed]

For comparison these are the ratios of the one I have to install

 

1st=3.76:1, 2nd=2.18:1, 3rd=1.42:1, 4th=1:1, and 5th=0.72:1. This is the same as the second option you posted for 1-4 and a little more OD.

 

And from what I can tell this is the ratio of the stock 3spd

1^st – 3.3 to 1;   2^nd – 1.78 to 1;   3^rd – 1.00 to 1.    

 

Jeff this is what I have for the 4spds but I am not sure if that carried over into the pilot house models.

Gear ratios:    1^st – 6.40 to 1;    2^nd – 3.09 to 1;   3^rd – 1.69 to 1;   4^th – 1.00 to 1.    

[Jeff Balazs]

 

Jeff, thanks. As you want to do I retained my rear end because I couldn't handle two projects at once. I now have about 15,000 miles on my transmission, all it has needed was an oil change and a new engine.

 

I talked to the guy that built my T5 (Earl Johnson) and asked him about ratios. The following gear sets would be ideal for your truck with the 3.55 differential:

 

3.76, 2.37, 1.49, 1.00, 0.86

 

3.76, 2.18, 1.42, 1.00, 0.81

 

This would give you full range on every gear. Nothing would be a "granny" gear or anything hardly used. The top set would give you slightly more torque, the bottom slightly better for highway driving.

 

He confirmed that a T5 could be built with those gear sets. Spline count TBD and you could chose between a "non world class" or "world class" version of the T5.

 

 John Thank you very much. You are all right .....no matter what Tim say's about you.

That first set looks very close to what I was thinking would be optimum. Will have to give this some more consideration. Again thank you.

 

Jeff

[Jeff Balazs]

For comparison these are the ratios of the one I have to install

 

1st=3.76:1, 2nd=2.18:1, 3rd=1.42:1, 4th=1:1, and 5th=0.72:1. This is the same as the second option you posted for 1-4 and a little more OD.

 

And from what I can tell this is the ratio of the stock 3spd

1^st – 3.3 to 1;   2^nd – 1.78 to 1;   3^rd – 1.00 to 1.    

 

Jeff this is what I have for the 4spds but I am not sure if that carried over into the pilot house models.

Gear ratios:    1^st – 6.40 to 1;    2^nd – 3.09 to 1;   3^rd – 1.69 to 1;   4^th – 1.00 to 1.    

Ed;

Yes those are the correct ratios for the 4 speed with 3.09 being just a bit tall taking off on hills. With these 3 top ratios to work with I generally run 2nd up to 15 to 20 mph....3rd to about 40 mph and then go to 4th. It is ok on flat pavement and very good downhill). But on hills that jump from 3rd to 4th is a bugger if the traffic is lagging back. Going uphill at sustained speeds over 50-55 is not horrible but drop below that or worse get behind a poke and I am then in a no mans land without the right ratio gear to work with.

 

Jeff

[Frank Elder]

http://www.allpar.com/mopar/transmissions/four-speed-manual.html

[TrampSteer]

... I almost always use 2nd gear for takeoff.

 

 

My Uncle John (Potato Farmer from central Wisconsin) only used first and third when we were out peddling door to door.

 

He said he was saving 2nd for retirement.

[pflaming]

Jeff, in actuality, there is no optimum gearing, there is only ideal gearing for each owners needs. A gear combo that is ideal in Southern California would be of little use in the gold country or the hilly curvy roads in New England.

I have an extra 230 engine with its factory OD and I amm strongly considering to put that in my truck, for me that would be iideal for driving to a lot of nearby fishing lakes in the nearby mountains. But then I grew up with OD's and two speed differentials so I know how to up and down shift an OD. With the OD I could pull a light boat or a small camper up the hill with ease, not so easy with a straight 3 on the tree.

I wish you well in your personal quest.

[55 Fargo]

So here is a ?, at what RPM, do you think your flattie, and it's gearing in your truck/car, is happiest, best fuel MPG, and highest vacuum reading s are at 60-65 mph?

I know as you know, these longstroke engines, are at there highest torque, at RPMs, not far from idle, much like a diesel, but what RPM is optimal, at hghway speeds in any of your opinion. I find mine happiest @ 2500-2800 rpm...

[Plymouthy Adams]

I get my best economy at 0 rpms......and it never sounds loud, busy or in any manner straining...

[Jeff Balazs]

Jeff, in actuality, there is no optimum gearing, there is only ideal gearing for each owners needs. A gear combo that is ideal in Southern California would be of little use in the gold country or the hilly curvy roads in New England.

I have an extra 230 engine with its factory OD and I amm strongly considering to put that in my truck, for me that would be iideal for driving to a lot of nearby fishing lakes in the nearby mountains. But then I grew up with OD's and two speed differentials so I know how to up and down shift an OD. With the OD I could pull a light boat or a small camper up the hill with ease, not so easy with a straight 3 on the tree.

I wish you well in your personal quest.

Paul;

I am not certain how to respond to this. What I am looking for is a set of ratios that allows me to get the most out of this truck.  If and when I find the right set up it should be able to handle almost every type of driving situation save perhaps dragging logs down a dirt path.  Simply put It is a matter of having the correct set of ratios available to keep the revs within the power band at a full range of speeds. You have that at your disposal and you can handle just about anything you will ever need to.

 

When these trucks were built I am certain they were more than adequate for the conditions they were intended for. Very few of us still live in that world. I know I don't. What I am trying to do here is take the best from 65 year old technology and make it work in todays world and do it well on a daily basis.

There is no way to do that with the stock gearing and ratios available. It has to be the biggest reason the stock restorations don't get a lot of road time.

John has found a combination that works well for him so I know I can do something similar and get the results I want.

 

Your assessment of what works well in SoCal might be useless in other areas......is in my opinion very shortsighted. We have hills and twisty roads.....and there is a 5000' mountain just a few miles from where I live. There is a grade there that you would be lucky to climb in second gear.....and the speed limit and prevailing traffic is 65 MPH. We also have traffic that is relentless and isn't exactly tolerant of slow pokes. I would say if it works well here it should be able to handle most anything.

 

Jeff

[pflaming]

In my opinion, to come close to your goal, you need more gear choices. Now an OD behind a three speed does some of that. If it is possible an OD behind a four speed and a 2:23 deferential so 1st gear is not a granny gear give you even more gear choices. Now, add a two speed rear differential and you double all your gears.

One more suggestion, have smaller diameter tires on the front and two pairs for the rear, choose the pair best suited for the task of the day! I see two choices, either drive your truck or drive yourself crazy. JMHO

[55 Fargo]

Jeff, the biggest issue, is that "fluid drive" slug, and of course the weight factor, with your 100 hp engine, that has miles on her too.

Going with a dry clutch, 3.73 rearend, and trans of your preference, may be your answer, and could help you out a lot. 

I can appreciate you trying to overcome your driving environment, thats got to be nerve racking, and by the sounds of things ain't getting better.

I suppose, if you were only using this truck to go get Ice Creams on Sundays, it would be okay. 

Using it as a daily driver, it has to be up to the task, for your safety sake.

There are others on this board, and on the HAMB who drive there old Chrysler flatties in the LA area, and in So Cal, how are they doing it? Or better what are they doing?

I know you will figure out what is best for you and your truck, and wish you well, look forward to your "plan of attack"......Fred

[Don Coatney]

In my opinion, to come close to your goal, you need more gear choices. Now an OD behind a three speed does some of that. If it is possible an OD behind a four speed and a 2:23 deferential so 1st gear is not a granny gear give you even more gear choices. Now, add a two speed rear differential and you double all your gears.

One more suggestion, have smaller diameter tires on the front and two pairs for the rear, choose the pair best suited for the task of the day! I see two choices, either drive your truck or drive yourself crazy. JMHO

PP I think you are attempting to respond to an issue that is well above your pay grade. Adding a four speed with over drive and using a 2.23/1 differential would make even make my long block Desoto engine falter in top gear on a flat road. I have sent you links to speed calculators in the past. Suggest you re-visit these calculators and get a better understanding of the relationship between engine torque and horsepower as it relates to vehicle speed.

[Plymouthy Adams]

besides that 3 or 4 speed is still 1.1 before OD

[Frank Elder]

I think you are really one of the good guys on here Jeff, but what I get from this thread is you aren't really ready to undo the work already done in order to make this swap happen.......maybe you are being a tad too picky.....that's your right of course, but there is never going to be the ideal driving situation....you need to adapt or be left behind so to speak..lol. I wish you the best of luck in your endeavor.

[pflaming]

My post was in jest, I thought the ideas were so out of the box that that would be noticeable, evidently not so. Tim has counseled me to not do as I did because the ideas set forth in any forum should be correct otherwise the forum loses it's integrity and he is correct, dead on. My apologies for my remarks.

That having been said, I like the choices available via an OD behind a three speed. Just a personal preference.

[Jeff Balazs]

Frank;

Thank you. One thing is certain.....I don't want to tear into this until I have a well thought out plan that I have a high degree of confidence in.

It will go as it is until I have a plan and the money and time to implement it.

It was my hope that in the course of this discussion others would benefit as well as myself. Sharing and knowing what our options are and dealing with some of the drawbacks is what discussion is all about. I think there has been some very good stuff brought up here.

I just wish some of it was simpler to prove out and implement.

 

Jeff

[John-T-53]

My post was in jest, I thought the ideas were so out of the box that that would be noticeable, evidently not so. Tim has counseled me to not do as I did because the ideas set forth in any forum should be correct otherwise the forum loses it's integrity and he is correct, dead on. My apologies for my remarks.

That having been said, I like the choices available via an OD behind a three speed. Just a personal preference.

 

Sarcasm detectors were not operational. I was gonna say you'd need to be an octopus to do all the shifting you talked about in your previous post, plus enlist a couple of trunk monkeys to jump out of the bed and change the rear wheels, roadside!

 

On the subject of OD's, Gear Vendors has another option if you want to drop the coin, but after looking into it, I deemed it not the best solution for our trucks. They offer a "divorced mount" unit which is the option for trannys where they don't make a bolt-on unit. Cost: $3000 and up. And No, this was not an intentional innuendo....

[Plymouthy Adams]

^{3000.00 for the GV OD is just waaaaaaaaaaaaaaaaaaaaaaaaaay out of the ball park IMHO..if modifying is your option then option the modification in a much better manner...many other better later model trannies available without the initial cost of the GV unit given both will entail similar work to install I believe sustainability will be greater also with a retrofit verse the GV...}

 

^{changed font size...sorry...just thought I had changed my screen size as I was looking for some detail in a couple drawings..}

Edited December 17, 2015 by Plymouthy Adams

[Don Coatney]

^{3000.00 for the GV OD is just waaaaaaaaaaaaaaaaaaaaaaaaaay out of the ball park IMHO..if modifying is your option then option the modification in a much better manner...many other better later model trannies available without the initial cost of the GV unit given both will entail similar work to install I believe sustainability will be greater also with a retrofit verse the GV...}

Tim, when you replied you inadvertently highlighted a font change button. Made your font so small I had to get triple magnifiers. I have done this before but learned to check and make sure no boxes are highlighted before responding. Wish GTK could fix this 

[John-T-53]

3000.00 for the GV OD is just waaaaaaaaaaaaaaaaaaaaaaaaaay out of the ball park IMHO..if modifying is your option then option the modification in a much better manner...many other better later model trannies available without the initial cost of the GV unit given both will entail similar work to install I believe sustainability will be greater also with a retrofit verse the GV...

 

Exactly. They do make a nice bolt-in OD for the Torqueflite, but then again it's the initial cost that's way outta line.

Edited December 16, 2015 by John-T-53

[Frank Elder]

Frank;

Thank you. One thing is certain.....I don't want to tear into this until I have a well thought out plan that I have a high degree of confidence in.

It will go as it is until I have a plan and the money and time to implement it.

It was my hope that in the course of this discussion others would benefit as well as myself. Sharing and knowing what our options are and dealing with some of the drawbacks is what discussion is all about. I think there has been some very good stuff brought up here.

I just wish some of it was simpler to prove out and implement.

 

Jeff

Thought out and planned out beats torn out........I posted the car 4spd link to show you some different ratios are out there, lets face it I doubt you'll ever be heavy hauling.

[Jeff Balazs]

Frank;

Well any way you look at it (so far) a transmission swap on this FD truck is going to be a lot of work. What I am really not certain of is if the results would actually be worth it versus say putting in a small block V8 and a modern automatic. If you add up all the costs including speed parts and an eventual engine rebuild it is probably more cost effective to go with the latter. This option goes against my grain but I have to face reality and I do want to be able to travel some long distances with this truck.

 

One thing that may help me make this decision is that my youngest daughter Kathleen has been accepted into the doctorate program at NAU in Flagstaff. If she ends up going there which now seems very likely then I am pretty certain I can persuade Momma to relocate to that area. I really like that region so this could be a huge win-win as far as we are concerned. But it is mountainous and towns are a fair piece apart. At that point reality kicks in and a significant power increase is no longer a what if. We should know more by the end of January. Kathleen has been nominated for a Presidential endowment and if that happens she will be there for at least 6 years...and.maybe longer. And it seems they really....really want her there. We are all very excited.

 

Jeff

[wallytoo]

sounds like good news - hope it works out.

 

hey, if you move there, even though it's hilly, maybe the pace/impatience is lower, and you could get away with what you have?

[pflaming]

If I lived in Flagstaff i would first off make certain I had a Flagstaff heater / AC. Second, I would not spend one dollar on the engine until I had driven the truck for one year. Remember, they built the roads in Flagstaff with such trucks. I would not hesitate for a moment to drive my truck to Flagstaff and look that country over very thoroughly, there is a LOT of beauty there. Finally, congratulations to your family and especially your daughter, because that kind of award is truly the result of a great family!

[Jeff Balazs]

Paul;

Thank you for the kind words. She has really worked hard and is very passionate about her work. We are very happy that she is getting this opportunity.

 

As far as optimizing this truck goes I will just say that I believe given the "right" set of gear ratios the truck would be fairly good in pretty much any situation.

 

Jeff