I have no intention of modifying my crossmember since the car is a low mileage 3x2s car and I might want to restore it back to stock someday, so I'm interested in hearing if anybody's been able to install the ROD 6 in their C3 without any frame surgery. I know the Richmond 5 will bolt in with just mods to the stamped trans mount (a $25 repop throw away), but the 6 looks pretty tight.

I spoke with a tech at Richmond today. He didn't wind up being incredibly helpful but he did suggest that some folks have installed the 6-speed without problems. Supposedly the 5-speed requires the trans mounting location be moved rearward 2 1/4" from stock. That seems workable. The 6-speed requires that it be moved rearward 3 3/4" from stock. The standard muncie mount is 14.2" from the bellhousing flange, while the 5-speed is 16.5" and the 6-speed is 18.0". I did some crude measuring on my 69 convertible and the ROD 6 looks to be awfully tight. Also, has anyone had any luck modifying the mid-exhaust bracket to fit?

The OD would sure be nice but not at the expense of carving up the frame. I'm sure I could manage with the R5 and 3.08s if I needed to.

Any comments or experiences?


[Modified by 69L71, 11:36 AM 2/5/2002]

 

You have to cut the frame to put the 6 speed in... unless you have a removable automatic trans crossmember.... which you don't. even then there probably would be some modifications.

Maybe some of the peoplle with ROD's will speak up with their experience. The above is from the BBFH article in Vette Magazine(long time ago)

 

69L71,

Based on the article in the following link, it seems that the trans COULD be installed in the car with the engine OUT.
http://www.idavette.net/hib/bbfh16.htm

Scroll down and read under the "Fabulous Fab work" section

"The Richmond fits the tunnel of a 1971 and will probably fit most other Mid-Years or Sharks with little trouble, however, its length precludes installation with the engine in the car unless the center crossmember is removable."


It would be alot of work to install it but if originality is the main focus, it may work. Some exhaust modifications would have to be done along with cutting some fiberglass around the area where the shifter comes up.

Bob

:cheers:

 

Thanks for the link Bob. I remember that write up from some time ago. It does suggest that installation might be possible with the engine out. That should be OK for me because I plan to install the whole drivetrain with the body off!

I measured the distance from the bellhousing flange to the crossmember on my convertible again (different car but same frame) and the distance is 19". Like I said, Richmond quotes the rear mount centerline being 18" back from the flange. Depending on the thickness of the mount boss (Richmond doesn't have it on their drawing) it should be doable, but damn is it close!

Can anyone measure the longitudinal thickness of the mount boss and let me know what it is?

 

Your welcome. I would also say that the mounting area where the trans mount sits would have to be modified, but not the crossmember. The only other problem that could come up are the adjustment of the shifter rods. The clearances were tight between the crossmember (I made mind removable) and the shifter rods (at the rear of the trans on the driver side where the rods bolt up to the lower shifter assembly).

Bob

 

I can't comment on the shifter rods and adjustment, but I'm slowly being convinced that the trans will fit with no modifications to the crossmember.

The stock Muncie installation has the stamped steel mount bracket the drops just barely lower than the top of the cross member, but obviously it's several inches forward. The stock rubber isolator monts about the bracket, raising the trans considerably higher than the crossmember. Maintaining the same mounting height it looks like a piece of angle iron, boxed to fit up with the two existing crossmember trans mount holes, will suffice as a replacement trans mount bracket. The rear mount rubber isolator would again be sandwiched between this new mount and the transmission. Even if the 19 inch dimension was a little tight (with the trans boss width), the trans mount sits above the crossmember so there shouldn't be any interference.



I can see that this would be a nasty installation (probably impossible) with the engine in place, but with the engine out (or in my case with the body off) it shouldn't be too bad at all.

I assume from Hib's article that the speedo cable and everything hooks up OK. Is that right?

Now to decide....

Note: If the above picture does not display Right Click the picture box and select show picture



[Modified by 69L71, 8:07 PM 2/5/2002]

 

Yes, sir. The speedo bolts up very nicely using the 4 speed's retainer clip. I would recommend using one of those 90 degree adapters like I did (from Mid-America for $45). In order to hook up the backup lights you will have to cut the wiring from your original set up but that would be easy to bring back to stock. The backup lights are very easy to wire in.

Bob :cool:

 

Just do the swap so I can test drive it and decided if I'm gonna do it will ya???? :D :cheers: :p:

 

Yeah right Mike.

But do you really think you'd be happy with that whimpy 350 after feeling a snorting solid lifter, rect port 427?

 

69L71,

I put the ROD 6 speed in without modifying the crossmember. I was as militant as you about modifying my original frame; however...

A small block Vette is easy to pull the engine and tranny out quickly if it doesn't have a lot of options. I felt that I could do the same thing with the BB. Once I got the L88 all nestled in, I realized there is not as much room to maneuver as was the case with the small block. I really regretted not modifying my crossmember when the body was off.

But, it can be done and the results are incredibly satisfying!! I had to fabricate my own rear trans mount and further shorten the mounting bracket, very similar to the design you posted. Also, I greatly enlarged the shifter hole on the transmission tunnel which helped a lot!. I formed a cover out of aluminum and pop riveted it into place re-establishing the same basic opening as the original. Since I covered the entire interior in Dynamat Xtreme, no one will ever notice.

I notched and welded the Longs shifter lever to move the **** back 2". If you use a leather later C3 shifter boot, virtually all of the Longs name on the shifter is covered up. I am making an adapter to fit the original black chrome **** in place of the cheap plastic one from Longs. The **** is the only cheap thing about the shifter or the trans. Everything else appears to be of exceptional quality and design.

I did have a shortened drive shaft made, bought a Corvette Turbo 400 yoke and had it shortened, and that was about it.

Of everything I have done to the car, the ROD 6 speed was the best improvement I made!

Chuck



[Modified by Chuck Harmon, 7:58 PM 2/5/2002]

 

:cry

:D

 

Be careful to get the geometry right. The R.O.D. mount MUST SIT 1" LOWER than the stock mount. Otherwise, the shifter will be too high and far forward, and the tunnel will need modification.

:chevy :chevy

 

Glad you're happy with the ROD 6, Chuck. Your car sounds a lot like mine although it seems yours is still a bit wilder. Its good to see that someone is so happy with a similar car. I was a little concerned that a 2100 RPM 70 MPH cruise might be a little low for those big rectangular ports. I'd still have to assume that a short runner, solid lifter, rect. port 427 is having port velocity problems at those revs. The 5-speed is still an option for that reason. A 3.08 rear gives ~2800 RPM at 70MPH. That's not screaming but it might be enough for the engine to start breathing... My 71 454/365 4-speed car sure loved 3000 PRM at 70MPH and it wasn't teeth rattling at all.

Thanks for the tip MV. That 1 inch does eat into some of the space for sure. I was assuming about a 1" isolator mount (same as my muncie has now), based on the standard mounting height. If it does indeed need to be dropped a little, the new/revised mount bracket can be made a little lower. That would bring the trans mounting boss closer to the crossmember, but as long as the height was maintained above the crossmember that shouldn't matter.

Speaking of height and clearance, what the hell is up with the Long Shifter? Why the BIG mounting bracket? Where does that sucker fit?




[Modified by 69L71, 1:11 PM 2/6/2002]

 

That pictures in your last post (69L71) looks like a Richmond Five speed set up since there are only 3 shifter rods (the six has 4 shifter rods). I don't know what all that metal is......

The shifter unit will fit up into the pass compartment slightly when you cut some of the fiberglass around it. I have some pictures that I will email you of what it looks like around the shifter area. I also traded that tall chrome Long shifter for a black one that is 1" shorter and more ergonomically feasible. I contacted Long, they shipped the new shifter after I gave them my credit card # and then credited my account once they received the other one back.

Bob

 

69L71,

I also have 3.08 gears and use the stronger .82 overdrive as recommended by Richmond for big torque motors. 75 and 80 mph cruising with traffic on highways is not unusual out here and the 6th gear makes it very nice as long as i keep the plugs clean with occasional high rpm power bursts (Italian tuneup).

Chuck

 

69L71,

I am running the same ratios as Chuck Harmon except sixth is a .62 to one (38% overdrive). With the 3.08's, I run 1700 at 70. I will see how my 454 runs with this setup. If it lags, I will go with 3.36's and boost up the final drive ratio from 1.91 (with 3.08's) to a 2.09 final drive ratio(with 3.36's).

My mouse motor L-48 can actually pull uphill on the freeway in sixth at 70-80 MPH (1700-1900rpm's). I was impressed with that, so I feel that the 3.08's will probably be fine in sixth with the 454. We'll see.

If you go to Chuck's website and listen to him drive the car, you will hear alot of wheel spin in the audio. Remember, this is with a 2.77 first gear and 3.08's in the back (8.53 to one FDR). I can't imagine the traction problems he would have with 3.55's or lower with that motor!!

Bob :cool:

 

Bob,

My gears are:

3.27
2.13
1.57
1.23
1.00
0.82

3.08 rear end, 2.53 overall gearing

Chuck


[Modified by Chuck Harmon, 12:44 PM 2/8/2002]

 

I hadn't really considered ratios yet. I'm sure I'll have a nice long conversation with Richmond when the time comes. I'd always done my basic figuring on the base 3.27, 2.13, 1.57, 1.24, 1.00, .76 gearset. While a 435 HP 427 with a more modern cam profile and headers is a good 500HP motor its not like it's gonna match the torque output of the 600 lbft 502s and 540s some of our friends on this board are running. If I were to drop down to the .82 OD I might just consider the 5-speed again. Torque shouldn't be a problem with a 1:1 ratio. Then I could conceivably drop down to a 2.73 rear (if I could find one with a posi) and have a 8.93 1st gear FD (very close to my stock 4.11 with an M21) and a 2.73 FD in 5th. That would save me some cash and space under the car. The ROD 6 with the standard gearset would give a 10.07 1st gear FD (we're talking the same as 4.56s here) and a 2.43 OD FD. Its hard to say if I'd even be able to harness the extra wheel torque of the 10:1 ratio. It might just wind up being tire smoke. not that there's anything wrong with that....

Bob, thanks for the pics. They were pretty helpful. I really loved the one of the trans sitting up on your reworked mount/crossmember. It looks an awful lot like my sketch above! :D

Still alot to think about. I'm awaiting the fabrication of my new collapsible body jig. Once its done I'm pulling the body back off and sending it out for paint. That's when I'll have to S*** or get off the pot. There is a part of me that thinks I shouldn't spend the bucks (~$3500) on a new rear and a trans of a car that will be a weekend toy. So what if it revs like a buzzsaw....? But I've also been very spoiled by modern OD cars. My 96 LT4 has a FD of 1.72 in 6th! Its not even turning 1900 RPM at 80 MPH! I know I won't make my '69 a total hotrod, but it will have a few tasteful mods with an otherwise restored appearance.

Its great hearing your experiences with these drivetrains. Its really cool that the total re-engineering required is the rework or replacement of the stock trans bracket, a new trans yoke, and some fiberglass trimming around the shifter opening. That's about as bolt-in as you can get (with the motor out, of course). Pretty decent engineering job by the guys at Richmond.

 

Chuck,

OH!!! So you are running 10.07 to one FDR. No wonder you have all that wheelspin!! Thanks for the correction on the first gear (3.27). I have the 2.77.... I wonder if I should go with a 3.36 rear now and bring the FDR in first to 9.31????:confused: :confused:

It would also bring sixth up to 2.09 to one...:confused: :confused:

Bob :crazy: :crazy: :crazy: :crazy: :crazy:


[Modified by Bob Turner, 9:52 PM 2/6/2002]

 

69L71,

If you have 3.08's, the 160+ top end is in the bank with the Richmond 5 speed. The first 5 gears are the same. I spent a great deal of time searching out a set of 2.73. Came close several times, i.e. "...had a set sitting on the shelf for years, just sold last week." Used ones were shot. I was ready to go with the 5 speed with 3.08's when the ROD 6 speed was brought to my attention about 10 years ago (yes, my project has been going on for longer than even this indicates!) I couldn't resist. I finally was able to have the best of both worlds. I liked the .82 with the 3.08's because it gave me the LeMans gearing which actually enabled the Heinz car to go over 200mph in about 1971 in his stock bodied 68 and detuned L88.

You won't justify the cost of the over drive through gas savings unless you live with the car on the road; but, the extra nice Longs shifter and the backup light switch that comes with it greatly offset the approximately $1000 extra for the trans. I can get wheel spin simply by flooring it in any of the 1st 3 gears. I haven't tried 4th at its torque peak yet of around 102mph like one of our anonymous moderators has (But you know who you are :D); but, it wouldn't surprise me in the least if that would toast the tires too.

The 22% gear reduction from 5th to 6th really makes for relaxed cruising with an engine I don't think anyone would ever have thought of as a cruising motor. The MSD 6AL helps a lot with the ability to do this. If the factory spec L88 is content, I would think that the L71 should be too.

Chuck