Optimum gearing ideas

[Young Ed]

  On 12/12/2015 at 3:09 PM, Jeff Balazs said:

John thank you again for your input. I went back through your build thread. Really first class stuff. I will have to look more at doing something like this. I would like to retain my rear axle but maybe there is a close ratio non OD version of this transmission that would do the trick for me.

In order to be truly useful as a fully functional daily driver it needs to be able to accelerate up hills within the flow of traffic. If it had a 5 speed without the granny gear and 5th gear that was at 1 to1 it would in effect be quite similar to what you have built.

 

Jeff

Footnote; Looks like a T5 is not going to be an option as they are all OD from what I am seeing. That isn't going to work with my 3.55 rear axle.

 

Jeff did you see any of the models that are OD but its not as much of a ratio? The one I'm using is .73 but I think they have some that are ~.9

I must say I'm following this with great interest because my project 47 is a 218 with a T5 and I'm not sure if the rear end I bought is a 3.55 or 3.7.

[Jeff Balazs]

Hi Ed;

That could make a pretty big difference in your application. I am pretty certain having a 3.55 rear axle and an OD ratio 5th gear is not going to be of any use to me. I have just enough power now to have a tiny bit of acceleration uphill now in 4th at 1 to 1. That is if I am moving at a decent clip to begin with.....like say 45Mph.

 

Here is another thing ...I am not sure how much difference the fluid drive in my truck makes in this situation. I kind of think there is a bit of an increase in the "flywheel effect" that may offset any power loss. You can feel a slight bit of cushioning effect at tmes but in general it is hard to tell it from a standard clutch arrangement. It may actually help some in this over geared set up I have. It is really hard to say. Once up to say 55 Mph the 3.55 feels pretty decent but I just haven't had much time to really test this. Hopefully after the first of the year I will get some time to test it out during a low traffic period. Up til now all of my driving has been during peak traffic hours.

 

Jeff

[Frank Elder]

How about shaving your fly wheel for a little more pep? Greg reports good results from this procedure.

[Don Coatney]

  On 12/12/2015 at 9:40 PM, Frank Elder said:

How about shaving your fly wheel for a little more pep? Greg reports good results from this procedure.

I am not sure if that would have a positive or negative effect with fluid drive.

[Frank Elder]

See, I need reminding since I got got rid of mine....never have I been happier with a modification.

[Young Ed]

  On 12/12/2015 at 9:03 PM, Jeff Balazs said:

Hi Ed;

That could make a pretty big difference in your application. I am pretty certain having a 3.55 rear axle and an OD ratio 5th gear is not going to be of any use to me. I have just enough power now to have a tiny bit of acceleration uphill now in 4th at 1 to 1. That is if I am moving at a decent clip to begin with.....like say 45Mph.

 

Here is another thing ...I am not sure how much difference the fluid drive in my truck makes in this situation. I kind of think there is a bit of an increase in the "flywheel effect" that may offset any power loss. You can feel a slight bit of cushioning effect at tmes but in general it is hard to tell it from a standard clutch arrangement. It may actually help some in this over geared set up I have. It is really hard to say. Once up to say 55 Mph the 3.55 feels pretty decent but I just haven't had much time to really test this. Hopefully after the first of the year I will get some time to test it out during a low traffic period. Up til now all of my driving has been during peak traffic hours.

 

Jeff

 

Well I just dug out my notes and per the seller I've got the 3.55 too.

[Jeff Balazs]

  On 12/12/2015 at 11:12 PM, Young Ed said:

Well I just dug out my notes and per the seller I've got the 3.55 too.

Well..........might be a tad too tall then. My tires have a diameter of around 29"......any chance you are running something a bit smaller? That might help a little. Your truck may be lighter than my 3/4 ton too and that would help. Another thing that could help is if you don't have much in the way of grades to deal with. Mine goes pretty good on flat ground. Problem is there are lots of fairly steep hills here. One of the nearby toll roads has a long steep grade that is actually pretty tough in a fairly modern truck. I have not been in a hurry to try it in the old beast.

 

Jeff

[DJ194950]

Jeff, no Big ideas for you, but would not be a complete rear end of the the same donor truck be cheaper than a rebuild of your rear gears  to try say a 3.7 or 3.9 ratio even if you have to cut/replace the spring mounts/.etc.?

 

Love my R-10 Mopar OD in my 50 4 dr.!

 

Too much changes for you, but my rebuilt 230 flattie w/ 3.9 rear gears runs great in town and freeways speeds, accelerates great for an old car.

 

No disc brakes but sure could use them!

 

Should not weight less than your truck?

 

 

 

 

4 sp. w/ OD  with at least 2-5 syncho'ed -with the right ratio rear gears.. I think you would love!??  Run 4th. or 3rd. up hills!

 

Best,

 

DJ

[Jeff Balazs]

  On 12/13/2015 at 2:34 AM, DJ194950 said:

Jeff, no Big ideas for you, but would not be a complete rear end of the the same donor truck be cheaper than a rebuild of your rear gears  to try say a 3.7 or 3.9 ratio even if you have to cut/replace the spring mounts/.etc.?

 

Love my R-10 Mopar OD in my 50 4 dr.!

 

Too much changes for you, but my rebuilt 230 flattie w/ 3.9 rear gears runs great in town and freeways speeds, accelerates great for an old car.

 

No disc brakes but sure could use them!

 

Should not weight less than your truck?

 

 

 

 

4 sp. w/ OD  with at least 2-5 syncho'ed -with the right ratio rear gears.. I think you would love!??  Run 4th. or 3rd. up hills!

 

Best,

 

DJ

It could be cheaper to do it that way. I would hate to disturb the braking system though as it is pretty much dialed in. I am really not sure what to do. Any of these transmission swaps are a fairly big job what with the FD and the parking brake etc....

I keep hoping to find a fix that is less involved than these we have been discussing. I would like to talk with a old time transmission specialist. There has to be someone around here that has done all sorts of swaps and maybe has another approach or solution. It certainly wouldn't hurt me to ask around.

 

Jeff

[Young Ed]

  On 12/13/2015 at 1:55 AM, Jeff Balazs said:

Well..........might be a tad too tall then. My tires have a diameter of around 29"......any chance you are running something a bit smaller? That might help a little. Your truck may be lighter than my 3/4 ton too and that would help. Another thing that could help is if you don't have much in the way of grades to deal with. Mine goes pretty good on flat ground. Problem is there are lots of fairly steep hills here. One of the nearby toll roads has a long steep grade that is actually pretty tough in a fairly modern truck. I have not been in a hurry to try it in the old beast.

 

Jeff

Are you running 15s or 16s? I plan on 15s. Don't have any purchased yet so I can't say what the diameter is. The neighborhood is nothing but hills but once you get further from home its not too bad.

[Don Coatney]

Perhaps a simple tire size change might help.

 

29" tires with a 3.55/1 rear gear at 2500RPM's equates to 61MPH

 

with 27" tires same everything else you would be going 57 MPH

 

going a step further with 29" tires with a 3.73/1 rear gear at 2500 RPM's equates to 58MPH

 

with 27"s tires same everything else you would be going 54MPH

[Jeff Balazs]

Ed;

I am running stock B-3-C wheels which are 15" with a 5 x 5 bolt pattern. I had several broken lug studs to begin with which are 9/16". There was nothing available to replace these in 9/16" so I used 5/8" studs all around. When I decided to fit disc brakes this resulted in a lot of extra work. It is one of the reasons I want to keep the rear axle I already have.

 

The tire and tire profile I chose was based on experience I had with other trucks. The Goodyear Wranglers have a very nice ride quality and are readily available. One thing I was concerned about from the beginning was getting a good ride. I knew this was going to be a daily driver so this would be quite important. If you go to a lower profile tire you can't expect it to help smooth things out as much. It just doesn't work that way. I chose a 3/4 ton with the 116" WB for the same reason. Pickups with a longer WB are generally a bit smoother riding than the same basic truck with a short WB. This is especially noticeable on longer trips.

 

Jeff

Having the cake and eating it too often poses challenges. I didn't choose the easiest path down the road. Having a fluid drive as an example adds another layer to the difficulties involved with making mods. But I can't start over so I just have to figure out a way to make most of what I already have to work the best that it can.

Edited December 13, 2015 by Jeff Balazs

[bluebanshee]

I'm running an S10 t5 with 28" (255 55 17) tires with either 3.73 or 3.55 rear end. The tag on my t5 was missing so I dont know the ratio but suspect it is .86 5th gear. I feel like I could pull a bit taller gears on the highways but probably shouldn't be go that fast anyway. It was some work the way I did mine but after putting on over a thousand miles from 4 lane highways to country roads it suits my needs perfectly. My 0-60 time is 18 seconds and could probably squeeze another second out of it.

 

 

 

 

[55 Fargo]

  On 12/14/2015 at 2:56 AM, bluebanshee said:

I'm running an S10 t5 with 28" (255 55 17) tires with either 3.73 or 3.55 rear end. The tag on my t5 was missing so I dont know the ratio but suspect it is .86 5th gear. I feel like I could pull a bit taller gears on the highways but probably shouldn't be go that fast anyway. It was some work the way I did mine but after putting on over a thousand miles from 4 lane highways to country roads it suits my needs perfectly. My 0-60 time is 18 seconds and could probably squeeze another second out of it.

Well it's better than my 0 to 60 , mine is terrible, even with 3.23 gears I have, it should be better than that.

Anybody else running above 3.55 gears that can attest to there 0 to 60 speed in there truck, with a stock or slightly hopped up engine..

[Young Ed]

  On 12/13/2015 at 1:51 PM, Jeff Balazs said:

Ed;

I am running stock B-3-C wheels which are 15" with a 5 x 5 bolt pattern. I had several broken lug studs to begin with which are 9/16". There was nothing available to replace these in 9/16" so I used 5/8" studs all around. When I decided to fit disc brakes this resulted in a lot of extra work. It is one of the reasons I want to keep the rear axle I already have.

 

The tire and tire profile I chose was based on experience I had with other trucks. The Goodyear Wranglers have a very nice ride quality and are readily available. One thing I was concerned about from the beginning was getting a good ride. I knew this was going to be a daily driver so this would be quite important. If you go to a lower profile tire you can't expect it to help smooth things out as much. It just doesn't work that way. I chose a 3/4 ton with the 116" WB for the same reason. Pickups with a longer WB are generally a bit smoother riding than the same basic truck with a short WB. This is especially noticeable on longer trips.

 

Jeff

Having the cake and eating it too often poses challenges. I didn't choose the easiest path down the road. Having a fluid drive as an example adds another layer to the difficulties involved with making mods. But I can't start over so I just have to figure out a way to make most of what I already have to work the best that it can.

 

What size tires are you running? I haven't gotten near close enough to buying tires. I don't even have wheels yet.....

I've got very little into this rear so far so I wouldn't feel too bad if I had to dump it and get a 3.73.

 

Not quite the same vehicle but my 48 plymouth with a stock 218, a 3.73 rear end, overdrive and I believe 215 75 15s. That car will still pull quite nicely uphill.

[1953 Farm Truck]

  On 12/12/2015 at 3:09 PM, Jeff Balazs said:

John thank you again for your input. I went back through your build thread. Really first class stuff. I will have to look more at doing something like this. I would like to retain my rear axle but maybe there is a close ratio non OD version of this transmission that would do the trick for me.

In order to be truly useful as a fully functional daily driver it needs to be able to accelerate up hills within the flow of traffic. If it had a 5 speed without the granny gear and 5th gear that was at 1 to1 it would in effect be quite similar to what you have built.

 

Jeff

Footnote; Looks like a T5 is not going to be an option as they are all OD from what I am seeing. That isn't going to work with my 3.55 rear axle.

I admire you for commuting in your truck.  If the T5 gear ratios for 1st, 2nd, and 3rd are suitable for your purposes, you would not have to shift into 5th (OD).  You could drive at freeway speeds in 4th gear which should be 1:1.  Just a thought.    

[Jeff Balazs]

  On 12/14/2015 at 3:59 AM, 1953 Farm Truck said:

I admire you for commuting in your truck.  If the T5 gear ratios for 1st, 2nd, and 3rd are suitable for your purposes, you would not have to shift into 5th (OD).  You could drive at freeway speeds in 4th gear which should be 1:1.  Just a thought.    

That is an option I suppose. Not certain if 5th would ever see much use though with the 3.55 I have. Perhaps to keeps revs down on long downhill sections ?

 

Jeff

[Jeff Balazs]

  On 12/14/2015 at 3:32 AM, Young Ed said:

What size tires are you running? I haven't gotten near close enough to buying tires. I don't even have wheels yet.....

I've got very little into this rear so far so I wouldn't feel too bad if I had to dump it and get a 3.73.

 

Not quite the same vehicle but my 48 plymouth with a stock 218, a 3.73 rear end, overdrive and I believe 215 75 15s. That car will still pull quite nicely uphill.

235 75 15s

Sounds like you may need to look at that based on what John has done with his truck. I do know my truck is pretty heavy compared to others here. I guess that is what happens when you add a ton of insulation and soundproofing. I am going to live with it that way though because compared to Fred's truck and some others I have heard running at speed it is almost silent.

Jeff

[55 Fargo]

Yes, noise, my truck needs door and side window weatherstripping/rubber badly. Most of what you hear is wind noise.

I like some engine noise, but if I want a real silent ride, I drive my Hemi Ram.

[Jeff Balazs]

  On 12/14/2015 at 2:47 PM, Fargos-Go-Far said:

Yes, noise, my truck needs door and side window weatherstripping/rubber badly. Most of what you hear is wind noise.

I like some engine noise, but if I want a real silent ride, I drive my Hemi Ram.

Well since this one is all I got I just figured it ought to be nice in that department. I still have a bit of a wind leak on the passenger door opening. I guess when my truck go T-boned years ago that opening got a little deformed. It still needs a little bit of work. Can't hear with the driver window down which is most of the time but I do hear with it up. Nothing major though. I will put it next to anyone's truck in this dept. For an old truck it is really quiet.

 

Jeff

[Young Ed]

  On 12/14/2015 at 1:13 PM, Jeff Balazs said:

235 75 15s

Sounds like you may need to look at that based on what John has done with his truck. I do know my truck is pretty heavy compared to others here. I guess that is what happens when you add a ton of insulation and soundproofing. I am going to live with it that way though because compared to Fred's truck and some others I have heard running at speed it is almost silent.

Jeff

I was thinking I'd go 225s on this one. I also think a pilot house is heavier than a job rated truck. Plus you've got that extra weight in that fluid drive setup and the 4 spd.

[Jeff Balazs]

Ed;

Yes I went with 235 because that was the largest that would fit the wheels I have. I didn't want it to look anemic either.

I was a bit surprised by the weight but I also have a heavy step bumper, the wood cross bed box and a good assortment of tools and spares aboard. It all adds up and I figure it is best to deal with the reality of it all.

 

I suppose I could go with a T5 and if the final ratio is too high for it swap the gearing in the rear axle. I don't think I will do anything before I try to get a bit of a boost out of the engine. I have never been completely happy with the carburation as it is.......and a few more ponies might help me decide what really needs to be done. I can commute with it the way it is for now. Progress will depend on available time and funds.......neither of which are in abundance at the present time.

 

Jeff

[Young Ed]

  On 12/15/2015 at 3:11 PM, Jeff Balazs said:

Ed;

Yes I went with 235 because that was the largest that would fit the wheels I have. I didn't want it to look anemic either.

I was a bit surprised by the weight but I also have a heavy step bumper, the wood cross bed box and a good assortment of tools and spares aboard. It all adds up and I figure it is best to deal with the reality of it all.

 

I suppose I could go with a T5 and if the final ratio is too high for it swap the gearing in the rear axle. I don't think I will do anything before I try to get a bit of a boost out of the engine. I have never been completely happy with the carburation as it is.......and a few more ponies might help me decide what really needs to be done. I can commute with it the way it is for now. Progress will depend on available time and funds.......neither of which are in abundance at the present time.

 

Jeff

 

Ha my truck I'm just getting going on was given to me over 10 years ago.

The one area you probably save a little vs mine is the bed cross members. My 47 will use 4 hardwood 2x4s. Thats gotta add some over those steel cross members.

[55 Fargo]

It is recognized, that Chrysler Flathead 6s, are at max torque at fairly low RPM, what 1200 -1600 RPMs.

Now having said this, I do not shift from gear to gar at this rpm, when going for maximum acceleration, more like 2500-3000 rpm.

Being that max torque is developed at a much lower RPM, and the fast these long stroke engines in a stock form are not high revvers.

It would make sense to find a gear spread , to keep this type of engine in it's power/torque curve.

There would be considerations such as weight, tire size, differential gear ratio, trans gear spread and ratios, engine HP.

These basic around 100 hp, need to be in there power band or just ahead of it in any gear, correct?

While we want to attain greater highway speeds with taller gears, we end up sacrificing power to get to these speeds.

I do find with my truck, it's basic 100 hp engine 3.23 gears P235 75 15 tires, 3200 lbs of weight, that after 2nd gear no problem, in power band, to 3rd gear, but 3rd to 4th, below power curve.

I am not sure my assumptions are correct, or if it is going downhill............LOL

[John-T-53]

  On 12/12/2015 at 3:09 PM, Jeff Balazs said:

John thank you again for your input. I went back through your build thread. Really first class stuff. I will have to look more at doing something like this. I would like to retain my rear axle but maybe there is a close ratio non OD version of this transmission that would do the trick for me.

In order to be truly useful as a fully functional daily driver it needs to be able to accelerate up hills within the flow of traffic. If it had a 5 speed without the granny gear and 5th gear that was at 1 to1 it would in effect be quite similar to what you have built.

 

Jeff

Footnote; Looks like a T5 is not going to be an option as they are all OD from what I am seeing. That isn't going to work with my 3.55 rear axle.

 

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.

Edited December 15, 2015 by John-T-53