4 to 5 speed.
Thread Starter
Instructor
Joined: May 2011
Posts: 197
Likes: 4
From: Rochester New York
4 to 5 speed.
I want to swap out the 4 speed on my (78 Silver Anniversary) daily driver in favor of one of the new 5 speed units out there. I have read conflicting stuff (as usual on the net) about gearing and the degree of difficulty and costing. I need to do my clutch this year so this is the time. If you have done this swap, what were your pros and cons. What is the 'real world' value of the original functioning 4 speed unit that I will sell to help defray the costs.
Gearing? Clutch recommendations?
PS
Before the purists jump me, per usual, please understand that this car is my tinker toy and enjoy wrenching on it as much as I do driving it. And the more I hack on it, the more YOUR original one is worth. LOL!
Gearing? Clutch recommendations?
PS
Before the purists jump me, per usual, please understand that this car is my tinker toy and enjoy wrenching on it as much as I do driving it. And the more I hack on it, the more YOUR original one is worth. LOL!
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
Most of the 5 speed OD units have a rather high 5 gear, ie 0.6 something. That's fine if you have around a rear in the mid to high 3 range, but mine had a 3.08 rear. I went with the Richmond 6 speed with a 0.76 OD because of this. Also uses all the original parts, bell, clutch, driveshaft, etc.
Thread Starter
Instructor
Joined: May 2011
Posts: 197
Likes: 4
From: Rochester New York
Most of the 5 speed OD units have a rather high 5 gear, ie 0.6 something. That's fine if you have around a rear in the mid to high 3 range, but mine had a 3.08 rear. I went with the Richmond 6 speed with a 0.76 OD because of this. Also uses all the original parts, bell, clutch, driveshaft, etc.
Last edited by ThePabst; Apr 11, 2013 at 09:40 AM.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Youll fall in love with that extra gear!
Have a 6 spd and to do it over again a 5 would be just fine.
With a 4.11 gear I can still barely use 6th (.050 OD) unless Im breaking the speed limits. Guess if you have a small cam you could use it at a lower speed but it doesnt really pull it well just cruises.
Have a 6 spd and to do it over again a 5 would be just fine.
With a 4.11 gear I can still barely use 6th (.050 OD) unless Im breaking the speed limits. Guess if you have a small cam you could use it at a lower speed but it doesnt really pull it well just cruises.
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
I swaped the trans when I did my 6.0 LS motor swap, so the motor was out. Also, if you have the non removable crossmember, cut it. I left mine intact. It will be cut when I need a new clutch.
What's your current rear? What motor are you running?
What's your current rear? What motor are you running?
How did the swap go with the Richmond? Did you go with pulling the motor or did you do it the traditional way. The 6 speed has caught my eye but it looks like that extra gear will set me back an additional 1K or so. My car is SCREAMING for another gear at 65-70. We are also well over 4 bucks a gallon for hi-oc where I live.
Thread Starter
Instructor
Joined: May 2011
Posts: 197
Likes: 4
From: Rochester New York
Youll fall in love with that extra gear!
Have a 6 spd and to do it over again a 5 would be just fine.
With a 4.11 gear I can still barely use 6th (.050 OD) unless Im breaking the speed limits. Guess if you have a small cam you could use it at a lower speed but it doesnt really pull it well just cruises.
Have a 6 spd and to do it over again a 5 would be just fine.
With a 4.11 gear I can still barely use 6th (.050 OD) unless Im breaking the speed limits. Guess if you have a small cam you could use it at a lower speed but it doesnt really pull it well just cruises.
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Le Mans Master
Joined: Feb 2011
Posts: 5,943
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From: Southern NH
How did the swap go with the Richmond? Did you go with pulling the motor or did you do it the traditional way. The 6 speed has caught my eye but it looks like that extra gear will set me back an additional 1K or so. My car is SCREAMING for another gear at 65-70. We are also well over 4 bucks a gallon for hi-oc where I live.
Thread Starter
Instructor
Joined: May 2011
Posts: 197
Likes: 4
From: Rochester New York
Since this is this years focus I'll research all the gearing issues before I pull the trigger. That will happen as soon as the ground hardens enough to get her out of the barn.
I own a machine shop and am also a welder so fabing up a new cross member is not a problem. Do you have a resource for procedure and pictures of a cut cross member and successful replacement? I'll copy it.
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
Not sure if the close ratio was very common in 78. Guessing it's more a matter of low rear end, weak small block. I think in 78 the T10 ratio was either 2.43 or 2.64, not much difference.
78 can be between 3.08 to 3.70. You're going to want to know that before you decide on a trans and gear ratios. Btw, the TKO varients typically offer 2 ratios. The richmond has about a half dozen to chose from.
Also figure in your cam. Big cams with lots of overlap make high rpm hp, but generally lose low end torque. Too low overdrive + rear end (numerically) + a big cam may make driving miserable and the OD gear useless.
Do a seach here on removable crossmember. There are a couple different threads and methods to do it.
78 can be between 3.08 to 3.70. You're going to want to know that before you decide on a trans and gear ratios. Btw, the TKO varients typically offer 2 ratios. The richmond has about a half dozen to chose from.
Also figure in your cam. Big cams with lots of overlap make high rpm hp, but generally lose low end torque. Too low overdrive + rear end (numerically) + a big cam may make driving miserable and the OD gear useless.
Do a seach here on removable crossmember. There are a couple different threads and methods to do it.
Last edited by Garys 68; Apr 11, 2013 at 10:43 AM.
Melting Slicks
Joined: Jul 2006
Posts: 2,291
Likes: 492
From: Salmon Arm, BC
[QUOTE= (Looks like the Exxon Valdese sank inside in the bell housing.) [/QUOTE]
LOL...I just spewed my coffee all over my keyboard....
I did the TKO600 conversion a couple of years ago, and it makes the car a whole new experience to drive. I went with the .64 overdrive, and that combined with my 3.36 rear gear gives 1800RPM @ 60 MPH IIRC.
There is another option of .82 OD which would be better with a 3.08 gear ratio. I don't think a 6 speed is needed in these cars, as the engines produce a pretty good torque band and pull through a good RPM range....Your thoughts may differ, and thats OK.
Do it and you'll love it!
LOL...I just spewed my coffee all over my keyboard....
I did the TKO600 conversion a couple of years ago, and it makes the car a whole new experience to drive. I went with the .64 overdrive, and that combined with my 3.36 rear gear gives 1800RPM @ 60 MPH IIRC.
There is another option of .82 OD which would be better with a 3.08 gear ratio. I don't think a 6 speed is needed in these cars, as the engines produce a pretty good torque band and pull through a good RPM range....Your thoughts may differ, and thats OK.
Do it and you'll love it!
Last edited by OMF; Apr 11, 2013 at 10:52 AM.
Thread Starter
Instructor
Joined: May 2011
Posts: 197
Likes: 4
From: Rochester New York
Not sure if the close ratio was very common in 78. Guessing it's more a matter of low rear end, weak small block. I think in 78 the T10 ratio was either 2.43 or 2.64, not much difference.
78 can be between 3.08 to 3.70. You're going to want to know that before you decide on a trans and gear ratios. Btw, the TKO varients typically offer 2 ratios. The richmond has about a half dozen to chose from.
Also figure in your cam. Big cams with lots of overlap make high rpm hp, but generally lose low end torque. Too low overdrive + rear end (numerically) + a big cam may make driving miserable and the OD gear useless.
Do a seach here on removable crossmember. There are a couple different threads and methods to do it.
78 can be between 3.08 to 3.70. You're going to want to know that before you decide on a trans and gear ratios. Btw, the TKO varients typically offer 2 ratios. The richmond has about a half dozen to chose from.
Also figure in your cam. Big cams with lots of overlap make high rpm hp, but generally lose low end torque. Too low overdrive + rear end (numerically) + a big cam may make driving miserable and the OD gear useless.
Do a seach here on removable crossmember. There are a couple different threads and methods to do it.
Last edited by ThePabst; Apr 11, 2013 at 11:26 AM.
Thread Starter
Instructor
Joined: May 2011
Posts: 197
Likes: 4
From: Rochester New York
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
Richmond offers both 5 and 6 speed OD trans. They both come in the same external case with a shifter included. But the 6 speed is generally cheaper. I got mine from SDparts, they had the best price.
Richmond also sells a 5 speed non-OD trans for around $2k, but it doesn't come with a $500 shifter. The 6 speed was the best deal for the money. About $3200 now. You can add the $100 67 hurst shifter handle if you want it to look original. You also might need an $80 output yoke. Everything else is reused from the original 4 speed.
https://sdparts.com/details/richmond-gear/rg7021626aa
Richmond also sells a 5 speed non-OD trans for around $2k, but it doesn't come with a $500 shifter. The 6 speed was the best deal for the money. About $3200 now. You can add the $100 67 hurst shifter handle if you want it to look original. You also might need an $80 output yoke. Everything else is reused from the original 4 speed.
https://sdparts.com/details/richmond-gear/rg7021626aa
Thread Starter
Instructor
Joined: May 2011
Posts: 197
Likes: 4
From: Rochester New York
I seldom go much faster that 75 these days, my back roading (in dear country) is to tight to go that fast safely, and the straighter parts of my commute is laced with troupers and speed enforcement; (It's how NYS finances all the hand-outs and gun confiscation.)
Racer
Joined: Apr 1999
Posts: 422
Likes: 3
From: Oxford MI
I just installed the TKO 500 in mine with a 3.08 rear gear and it is great. I bought the Keisler kit which made the swap relatively simple, just bolt it all together. I'm running a small block 400 with 11 inch clutch. I used a comp extreme energy cam and have no issues with accelerating in 5th gear from low rpm. 1800 rpm at 70 mph is fantastic in this car.
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
I was day-dreaming about this the other day. I think I'd prefer a R5 if I could find a low enough gearset to go with. I've already got the TKO600 w/ 3.55 gears, though, so maybe for the next car.