Big block, Automatic OVERdrive and a way to do it cheaper...

[mopar_chuck]

Are you dead set on an auto? Or would you consider a 5 speed conversion from silver sport? I believe Dennis H has a thread on installing one in his car right now. In the end it would probably be more money but at the same time, a stick car is more desirable and therefore makes your charger worth more....

 

[Kern Dog]

Thanks. The value of the car is only important to those with intentions of selling, just like real estate, right?
I'm not that much of a fan of manual transmissions. I can drive them just fine but they just don't appeal as much to me.

 

[Kern Dog]

Are you dead set on an auto? Or would you consider a 5 speed conversion from silver sport? I believe Dennis H has a thread on installing one in his car right now. In the end it would probably be more money but at the same time, a stick car is more desirable and therefore makes your charger worth more....

Okay....Now call me CRAZY but I have been thinking about the manual transmission idea.
There are advantages with them. Usually they have less parasitic losses and greater efficiency as compared to a 727. They can be a lot more fun to drive. The gear ratio choices and overdrive ratios are pretty interesting.
Hmmm.....

 

[mopar_chuck]

Okay....Now call me CRAZY but I have been thinking about the manual transmission idea.
There are advantages with them. Usually they have less parasitic losses and greater efficiency as compared to a 727. They can be a lot more fun to drive. The gear ratio choices and overdrive ratios are pretty interesting.
Hmmm.....

It just seems like if you want overdrive, a stick is just a more practical, easier option. Plus you get the pleasure of listening to the engine wind while in control of rowing the gears.

 

[mopar_chuck]

I would do it to my RR in a heartbeat but the resto process isn’t cheap and the 727 is all rebuild and ready to go. It’s one of those mods I plan on doing “a few years after” it’s on the road

 

[Kern Dog]

I had a Duster that was a slant six auto that I converted to a 360 & 833 4 speed. I enjoyed the car for what it was....a recreational car, not a daily driver. I only owned that car in finished form a short while so I didn't get to know the dynamics of the car very well.
Its not that I lack the skill to drive manual transmission vehicles, I just didn't place serious thought on doing a conversion to the Charger. I like to corner and cruise, not drag race. I had a 4 speed in a Camaro for several years. I felt that I was a better driver in the Camaro when it had an automatic though peeling out was more fun with the 4 speed. It may have been a matter of the gear ratios and gear spacing in the Camaro. Cornering with the car, it sometimes felt like I was not in the right gear for corner entry or exit. The rpms either being too low or too high. That effects traction and to be honest, my confidence to drive. It can be annoying and nerve wracking if you feel you are spinning the engine to the point of turning an "internal" combustion engine to an external combustion one!
The new crop of 5 speeds seem to have a closer gear spacing than I thought. Nice!

 

[Kern Dog]

I just checked Google to see what the gear ratios were for the GM Saginaw 4 speed. Mine had a 3.11 first gear with a 3.42 diff gear.
1st) 3.11
2nd) 2.20
3rd) 1.47
4th) 1.0

This might explain why second gear was too low of a gear for cornering and 3rd seemed too tall.
What is the expected cost of a Silver Sport 5 speed swap?

 

[wyrmrider]

Saginaw looks about the same as a T-10 U
Had one from a Marlin in my AMC 6 Turbo big drop first to second

 

[Hey-O]

I just checked Google to see what the gear ratios were for the GM Saginaw 4 speed. Mine had a 3.11 first gear with a 3.42 diff gear.
1st) 3.11
2nd) 2.20
3rd) 1.47
4th) 1.0

This might explain why second gear was too low of a gear for cornering and 3rd seemed too tall.
What is the expected cost of a Silver Sport 5 speed swap?

Check the GV web site. There was a mopar in the ad that was a 4 speed with a GV behind it. It had a video of him running it through the gears.

 

[mopar_chuck]

I just checked Google to see what the gear ratios were for the GM Saginaw 4 speed. Mine had a 3.11 first gear with a 3.42 diff gear.
1st) 3.11
2nd) 2.20
3rd) 1.47
4th) 1.0

This might explain why second gear was too low of a gear for cornering and 3rd seemed too tall.
What is the expected cost of a Silver Sport 5 speed swap?

I’m no expert, but that sounds like a wide ratio transmission which would not be that great for a performance street car. I would assume that it would have had that “bulldog low” first gear as well. What a huge gap between first and second too. My Camaro with the super T10 was close ratio. It was fun on the street.

 

[wyrmrider]

A vet with the 2.20 low is fun on the street with the right gears - like 4.11s, or on the track with appropriate gears
the low ratios are also great on the street with tall gears
the overall low gear ratio works about the same and 4th can be more highway friendly

 

[Kern Dog]

I can see how a transmission with close spaced gears would work well with an engine with a narrow power band. If your engine is a gutless wonder until 5000 rpms, you would want a transmission where it would keep you in a narrow RPM spread to accelerate faster. Many stock engines made their power in a wider range, say 1500 rpm to just under 5000.
I've looked at the TKO 600 5 speed transmissions and notice that the wide ratio version has a 3.27 first gear with a .64 5th. The other one is something like a 2.97 1st and a .82 5th.

 

[andyf]

My '65 Coronet has a Doug Nash 5 speed in it and a Dana 60 with 3.23 gears out back. The gear ratios are just about perfect for a street driver that can quickly go triple digits whenever you want. However, I find that it is a hassle to drive a manual transmission in traffic these days. Getting stuck on the freeway in stop and go traffic is a pain, especially if the freeway has a slight upwards slope on it. Constantly riding the clutch and slipping it to get the car moving again gets old super fast. It is complete hell on a hot summer day......

 

[MStauff000]

Yes I do. However, I'm not done yet. The car had to get put on the back burner for family and house projects. I'm running the microsquirt trans controller and a us shift throttle position sensor on my edelbrock. I think the trans controller is around $400 with the harness. It is one of the cheapest available. Here is a link of what I have. https://www.forbbodiesonly.com/moparforum/threads/4l60e-to-a-big-block.48547/ I'm actually going to try and get the wiring finished next week while on vacation.

What do you do about shifter linkage? Im in early stages of planning this swap into a 70 Challenger and not sure how difficult it will be to connect to my console shifter?

 

[747mopar]

Here's the ratio's for my T56, love them but 6th is ridiculous. Perfect 5 speed gears with an extra gear souly for high speeds.

 

[Dennis H]

Related note, friend with a Passon 855 in a ‘Cuda says he went to a 410 rear from 373 so he can use 5th without exceeding speed limit.

 

[Kern Dog]

Is this a guy with a cowboy hat and a propensity to tear off radio antennas ?

 

[Kern Dog]

I've looked at the TKO 600 5 speed transmissions and notice that the wide ratio version has a 3.27 first gear with a .64 5th. The other one is something like a 2.97 1st and a .82 5th.

I just got a quote from the guys at Silver Sport. The Tremec 5 speed they listed has a 2.87 first gear and a .64 5th gear. That is surely considered a close ratio type. That puts my 3.55 axle to a 2.27 in overdrive. Too tall, maybe? First gear ratio 2.87 X 3.55 =10.18 to 1 as compared to a 727 2.45 X 3.55 of 8.69 to 1.
All the math is fun to me, speculating just how the car will respond to the different ratios. The new Challengers that use the Tremec 6 speeds use a deep axle gear...something like a 3.92. They have a double overdrive though and a .50 6th, right?
The price quote I got includes the pistol grip shift lever, a hydraulic clutch setup, everything needed for the swap and FREE shipping. $6584.
I expected it to run over $7000.

 

[Kern Dog]

The 2018 Challenger Scat Pack cars use a Tremec with a 2.97 1st gear, a .50 6th and a 3.90 diff.
I post this just as a comparison to how the modern cars are geared compared to our classics. It would appear that this SST trans being a modern design, coupled with a hydraulic clutch...should deliver smoother operation similar to a newer car.

 

[Dennis H]

The 2018 Challenger Scat Pack cars use a Tremec with a 2.97 1st gear, a .50 6th and a 3.90 diff.
I post this just as a comparison to how the modern cars are geared compared to our classics. It would appear that this SST trans being a modern design, coupled with a hydraulic clutch...should deliver smoother operation similar to a newer car.

For sweet spot, can your motor roll on easliy at 1k? My mild build does. Higher horsepower could lug under 1050 or so. I did not know top cruising rpm’s until job done. Got lucky.