Found this photo online. So basically, as long as this rod is pulled UP or removed completely, the shifter can just be pushed over to find reverse.





I wonder what the cons are of doing such a mod..

-- Joe

 

Before defeating reverse lockout, check the shifter mounting bracket.
The con is engaging reverse while moving forward

 

reverse doesnt have a synchro...you wont get it in while moving forward.....The worry is putting it in reverse and thinking your in first at a light.....You say you have a Hurst shifter maybe? I would put it in and see how it firts. YOu might be able to make the mounting plate out of a piece of stock

 

yes it wont go in but will make an incredible grinding noise which cannt be good at any speed.

 

But you will only do it once...LOL.

 

The Hurst Competition Plus shifter uses a rather stiff spring to keep you from engaging reverse accidentally.
The muncie shifter has no spring, that rod is all there is to keep you out of reverse.

Now it "probably" wouldn't actually go into reverse while you are shifting, but it could go in far enough to grind some gears a lot and chip a gear tooth.

 

The solution to a weak Muncie / Borg is the Autogear M23Z 4 speed. Its all the parts they made to improve the durability and strength of the original 4 speeds, assembled into a NEW transmission, for just over half the price of a TKX. I bought two of them from Jodys Transmission, ....one for the 77, one for the 69. Much better quality all around, stronger cases, better gears.

 

What are the 1st-4th gear ratios on your particular transmissions pictured? From what I've read, you can get them in a decent variety of gearset ratios. Wonder if they have a taller (numerically lower) 4th gear. Not too much, but something like a .90 would be nice. Spreading out the gear ratios a bit could be an idea so that 4th doesn't just become and overdrive....

 

I can find out exactly.....but I do know first gear is 2.99, second and third are then evenly spaced between, and fourth gear is factory stock 1:1...no overdrive. You read my posts before,....I have no need or desire for a fifth gear, and especially not a sixth gear. It is way more important to me to retain the original design, than cut up crossmembers, custom drivesharts, tunnel mods, etc, and end up with a modern transmission in my 69 Corvette. I love the original shifter, and the original transmission feel. I have a 2006 C6 Corvette....with six gears in a Tremec, and its similar to what the rage is on C3's.....NOT impressed. Its nothing special to me. It notchy, and feels no better than my Borg T-10 did. The Autogear M23 4 speed is a high quality and strong version of the Muncie / Borg Corvette transmission......for me....its the best choice. But....the mob won't agree....TKX TKX TKX TKX TKX blah blah blah.

 

a 4 speed cant have a fourth gear that is anything other than 1:1 because it is a straight shaft....you could flip the 3,4 lever and turn third into an overdrive though with a smaller gear so it would shift 1,2,4,3 but the pattern would be the same

 

Most of the pre 1980 ST10 had either 2 or 3 grooves on the input shaft. They came in 350 Vette and 455 TA. I have a 2 groove one that’s 2.43:1 1st gear. I think 3 groove is a little lower. Either will work good with a 3.70 rear gear.

 

As Corvette Passion said, if I want a stronger Muncie, this is what I would do.

https://www.motortrend.com/how-to/in...r-engineering/

 

How do you figure? The first online price I found was for a bare transmission ON SALE for $3149-. My TKX was $3300-. The only other REQUIRED items are a shortened driveshaft (which you can get done locally for $200-, or a case of beer if you know a guy), and a relocated transmission mount (which a handy guy with a welder could do for free). Everything else, clutch, flywheel, bellhousing, etc, is the same cost for either transmission, or just use what you have. The $6K price for the kit that gets thrown around is for a complete auto to manual conversion, with a new pedal set, hydraulic clutch, custom driveshaft, custom trans crossmember, new bellhousing , and work to move the shift lever over to the C3-offset standard. Still a great deal (I think), but optional.

So, if the OP were to assemble a TKX, TKO, or other junkyard Tremec kit himself, he could get a center-shifter, and solve the offset shifter issue.

But anyway, here's the spreadsheet with some transmissions. The first line is a stock 80 L48 4-speed, the rest are the OP's diff ratio. This assumes a 27" wheel/tire diameter. With a 3.70:1 diff, he likely has an M21 Muncie? There are other TKX and Tremec Magnum options, I chose the options that have the TKX mirror the 80 B&T ST10 (plus a bonus overdrive), and the Magnum mirror the M23Z (plus TWO bonus overdrives, and likely some tunnel modifications). PM me for the editable version if anyone wants to play with the numbers themselves.

 

When I priced everything I would need to put a TKX in my 69 manual Corvette, it was over $5000. I got quote from Silversport. The M23Z 4 speed was $2900. But the money is not the issue, but it is a factor in a decision.

I already stated my opinion, more importantly what I want in my car....which is what really matters to me. Seems like people in love with 5 speeds and up just don't understand anything else. Do what you want...and so will I. The term "better" is a matter of opinion...not a fact. Just like electric cooling fans and Borgeson steering.....but those that choose those just can't stand it unless everyone agrees with them. Not interested in bickering about it......the OP can make his choice.

 

ford did this with early 80's v8 mustangs. a friend had one i drove. he had snapped the direct drive synchro off of 3rd and had a 3 speed. 1st, 2nd and OD.

 

If you've been driving these things long enough, you'll know by feel whether you've put it in reverse or a forward gear. Reverse feels different because engaging it is gear on gear. Any forward gear is the interior splines on one of the sliding sleeves engaging the dog teeth just past the synchro cones. Much shorter engagement travel and you can feel it in the shifter.

 

I think I'm going to modify the factory shifter and try that for a bit. If I don't like it I'll try something else.

Thanks!

 

Thats the only advantage to being 5 ft 6 in, I fit nicely in a c-3 and I don't hit leg when shifting.