5 speed vs. overdrive

i have a 76 b that i am about to do some work on. and cant decide between a 5 speed or and overdrive trans. what are the ups and downs to both? anyone have an overdrive in there car? how easy is it to operate? i've herd they can be a headache if they start to have problems

Overdrives are kind of cool, but as far as reliability and function, a 5 speed is far superior.

I believe overdrives are at a premium in the states. I would guess a 5 speed would be cheaper.

I have a 5 speed (LT77) and prefer it, but I changed because the O/D was not up to the power I have. I think T5's are cheap in the US.

David

the 5 speed is about $700 more and requires recalibrating the spedo

how much power are you making?, im gettng ready to do a top end rebuild with a mild cam and 1 3/4 su's......

Overdrives are pretty tough as long as they've been looked after. It seems most of the issues are with the electrics (which are usually easy to fix). Even mechanically, they're repairable.

To operate, it's just a matter of flipping a switch. Lock-out switches prevent the o/drive from operating in reverse and 1st & 2nd. Later boxes lock-out 3rd gear as well. They're becoming a bit scarce but are out there. Prices may soon reflect this fact.

I've got a Nissan 280zx 5-speed in my GT. I like it. I used the Rivergate kit to install it. Others have used the Ford Sierra T9 'box and like them as well. The 'box sold through Moss is the Ford unit.

I went with the 280 'box as I couldn't find an o/drive close by and thought I'd go this route.

Have a look using the "search" button above for lots of info on this subject. With either the o/drive or the 5-speed, you'll love it.

yeah i have both readily available and both are rebuilt trans ........i realy dont want to devalue the car by putting in an expensive item like that, but i am looking for a better drive. i cant take the car at highway speeds when its sitting at 4 grand at 60mph

I have about 175BHP and my O/D box broke. 3rd Gear. I had overdrive on 3rd and 4th but if I had stopped it from working in 3rd, it might have not broken.

I was told that O/D boxes are pricey over there, but I could be wrong. V8 O/D boxes are hard to find, where as I thought a second hand 5 speed would be cheaper.

Mike Your engine will run all day long at 4K without problems

I have the Ford unit in my 66 and like it. but as written above, overdrives are pretty cool. You'll get good advice on the pros/cons of each approach if you call John Esposito at Quantumechanics in CT. He's the LBC gearbox expert in the States.

yeah that is actualy where i was going to get the trans from................those guys are the best around

There are a ton of threads on this, all accessible with a search. The short of it is...

Overdrive advantages:
6 forward gears
3rd OD is very useful in traffic and for climbing hills.
Change gears (two of them) with a switch, with your hands still on the steering wheel.
Adds value to the car.
Retains vintage feel of the car.
Bolts right in, no modifications.
Overall cheaper than 5-speed.

5-speed advantages:
Slightly lighter weight than an OD box.
A little less gear noise.
Some people prefer the gear spacing (OD boxes come with several ratios)
Less to go wrong (no electrical circuit except for reversing lamp)
Local garages can rebuild it although they probably won't take it out of the car for you.

My personal preference is for overdrives. 5-speeds are a great addition to an MGB, but you will lose some of that vintage feel if that's important to you (it is to me). Also, I wouldn't plan on recovering the cost of the 5-speed unless you find a buyer who really wants one and will pay extra for it.

Nothing cooler than shifting up and down with a switch in an old car! :)

DavidTetlow Wrote:

I've had both and prefer the 5 speed. If you had a stock 4 banger with the a working 4 speed tranny, I dont feel that adding overdrive-or adding a 5 speed is worth the money and effort. The four banger will hum/clatter along for a very long time at the slightly higher rpm's. If you're looking to get more power, then think about a change of the motor (v6 is a very reasonable way to go for many folks), and a change of transmission.
With a V8, I'm sure it's a cheaper and more reliable way to go (5 speed). For parts that don't show it and for someone not hung up on originality, it makes little sense to me to use something that's 40 years old and kind of rare, instead of one that's relatively new-5-10 years old-, widely available, with parts are easier to come by and really great spread of ratios.

scotabbott Wrote:

The engineer who rebuilt my Std box believed the V8 overdrive box was worse than the Std version. He said he never knew of one that had survived more than 15k miles without breaking. He believed that if you had a std box with O/D removed in 3rd you had the best solution. (FWIW)

I agree with Steve that if you have a standard B then the std box is a very reliable and the best way to go but if you want to get the best of both worlds, as I did, in that you want a beautiful looking classic car with a bit of extra go then you should go with the best engineering solution which would be the 5 speed, and not the old version I have, but a modern one. (I could not afford a modern box)

My personal recommendation is if you have a standard B then go with an O/D box (I believe non O/D is uncomfortable to tour with) and if you want a sportier, tighter car go with a modified suspension, brakes, diff and the 5 speed box.

Don’t forget its your car and if its right for you that is all that matters.

I like the coolness factor of the OD. It does make a big difference. I have friends with the Nissan 5 speed and they are happy with it. Your car, your choice.

We have a Rivergate conversion in ours and like it. Our friends have a big Healey with a stock od and that is very cool also. I might have gone with the od but at the time everything I could find, plus rebuilding it, came out to about the same amount of money and there just didn't seem to be any available at the time.

Joe

i think im going to go with the od unit...............................joe, is your car lowered or is it the angle of the shot that makes your car look like its on the ground? i like it!!!

O/D for me in the street car. Coolness factor.
5-speed (if they will allow it) in the racecar. Durability and flexibility ratio-wise.

mjamgb Wrote:

In fear of hijacking the thread...

I thought SCCA allowed a 5-speed to replace an OD gearbox? Perhaps that allowance was rescinded?

Doesn't matter 'cause the racecar is all on paper as yet so rules are for certain goin to change before I so much as turn a wrench.

Think that was SVRA. Premise was that the OD formed what was functionally a 5 speed, so equalize the playing field by permitting 5 speed

Hey Steve, there's nothing wrong with making a car engineered in the 60s a little better by adding a 5-speed tranny, a supercharger and maybe some other more reliable parts!

You know as well as I do that adding something like a 5speed and a SCer doesn;t really change an MGB all that much.

I don;t want a newer sports car, I already have one, I want my MGB to be able to cruise at over 100mph so that I don;t have to look at the huge Ford excursion grille in my rear view mirror.

I don;t want a miata, or anything else, I want a better MGB!

You do too!

I choose the T9 s-speed trans because when i bought mine I only paid $1800 for the whole kit and kaboodle, all new. A rebuilt OD from Moss was $2K at the time, Plus, I got to choose the gear set that I wanted, there's no calibration of the speedo, its a bolt in swap. and all it does is make the car more streetable, and better at high speeds, its not gonna change the "essence" of the MGB, otherwise I wouldna dunit!

I love this arguement, it comes up about once a month and its ALWAYS the same! Same people, same arguments!

hahahahahhaaha

B

Mike check this place out. This is where I bought my 5-speed at.
<http://atlantaimported.com/MGB%205%20speed%20transmission.asp>
I paid about HALF of that price, he may or may not offer a discount!

No argument here, a modern 5-speed is a better piece of engineering. It uses modern metals, hardening treatments, bearings and manufacturing methods. But that doesn't make it a better driving experience, it just makes it different.

Opinions fly every time this debate starts but if we stick to the facts, it's a very simple topic. If you want to get the full vintage M.G. experience, get an overdrive. If you want a modern feel in the shift lever, get the 5-speed. Both will give increased highway gearing. The rest is trade-offs between the two.

I just don't buy ODs aren't reliable. Been around Bs since the mid-70s and never had one go out. Just make sure it gets cycled some (not for trailer queens), clean out the filter once every couple of years. The silly things work well.

I suspect for a '76 the cheapest way to go is an OD once you factor in install cost.

For a MK 1, the OD verses 5 speed is an entirely different question. That crash box gear box is definitely an antique. I did the OD on my '65, but my wife won't drive the darn thing. She hates the non-syncro 1st. And finding the ODs at a cost price becomes an issue. I'd rather see a 5 speed in a MK 1 than a tunnel mod to cram in the 4 sycro gear box with OD.

That's where you and I differ, it DOES make it better.

I could barely get over 100mph with my regular 4spd. I'd be way up at 7 grand to get to 110.

I was tasked with deciding on an Od or a 5 speed. when I found out that I could choose my ratios, and I had all kinds of aftermarket goodies, and I'd save $200, it was a no brainer.

So, to ME, it IS BETTER, not just different.

B

I agree, overdrives are quite reliable. A 5-speed has fewer things to go wrong, but that doesn't make the OD unreliable.

My OD came out of a 77, went in the 73 six years ago, and has never given me a moments notice. I love it. I also put one in the GT. As Steve says, it's hard to beat 3 1/2 and 5th with the flick of a lever. At 100mph the car isn't even breathing hard.

Ya, Alonzo, you're right on. I actually retrofitted a 77 gearbox to my 67 back in 1985. Back then there was a lot of support for MGBs. There was a junkyard selling the conversion kit, along with a guaranteed used later 4 synchro box for about $200. I STILL have that same set-up, well until I ripped my car apart for the resto.

The later box and the early box are two entirely different animals.

When my early box went out, it did so in style! at about 35-40 mph, in the middle of an intersection I heard and most definitely FELT a huge bang and the whole car came skidding to a halt right in the middle of the intersection, the tranny completely tanked and frozen. Nothing had even hinted at a problem until that very moment.

2 bills and a weekend later I had a new 4 synchro box in it.

But, now is a different day, and the idea of a modern 5 speed with loads of strength just seemed right at the time! Plus, the price was right.

NOW though, sheeesh, these things are over $3K for the very same conversion that I paid not a penny over $1800 in 2004, that's INSANE!

B

Kathy has been looking at the 5-speed for her LE. I, on the other hand, have been keeping an eye on an OD tranny on eBay. With the Rivergate conversion you need to have the 5-speed tranny on hand or the cost goes up. The OD I'm looking at on eBay is only $475, but damn the shipping is $295....of course it is coming from the UK. Personally I would prefer the OD to keep the car as original as possible.

Mike, I'll bet you still cant decide!
As you can see, opinions vary and they always will. I drove my '73 for 12 years without an OD. Ran the begeebeez out of it. All kinds of roads/highways/interstates. At the time, 4 speeds was enough even on long trips (D.C. to Chicago, Chicago to New Orleans, D.C. to Daytona etc.). I beat myself up with high speeds hours on end and didnt care. Then someone told me I should get an OD. Why, I asked. Because its quieter and saves gas on your long trips. COOL, said I. Installed my present OD in '86 and 22 yrs later have never had one speck of trouble with it! Well things have changed since then. I dont drive those long trips anymore but I would not part with my OD either. I probably use 3rd OD (my favorite gear) more now than I used to use 4th OD.
I've never been in a B with a 5 speed but I'm sure it works just fine. I dont know the final drive ratios either but for me, OD all the way. No kits, no extra parts, and it's true British too. Not trying to convince you one way or the other. Before you do decide, take a good look at your driving style and what you will accomplish with a cash outlay for either unit. Maybe you dont need one as someone already hinted. Put the money somewhere else.
My Grandfather always said (and I remember this like it was yesterday) When money starts to burn a hole in your pocket...put it in the other one!
RS

Mike Chalf,

I've never compared it to other B's but I've often thought that it sits low. I put new stock springs in the front when we restored it but the rear leafs looked fairly new so we reused them. Could be the tires as they are considerably shorter than what was on the car when we bought it which was a mixture of brands and maybe sizes.

Joe

For 38 years I have DRIVEN & worked on British cars only & have built Austin america AUTOs to M.G.B. G.T. V-8s & my first 74.5 V-8 has 496,689 miles on her tonight. I have worked on the O/Ds & with Rivergate & the 280Z 5sp. I can rebuild the 5sp in 3 hrs. & the O/D in 8hrs if I am lucky & after I find all the parts. The only way you can break the 5sp. is run it out of oil with the 1800cc B motor that puts all the H.P. it can make! What NO ONE HAS SAID is I had a rear oil seal go bad on a 80 B. Started on PULLING THE TRANS. ONLY at 9 am & was done & went to lunch at 12 THE SAME DAY!!!!!! I don't care how good the drugs are that you are going to take, you ain't going to get the job done that fast with a B trans! The 5sp. kit that rivergate & I sell are thought out very well & are no problem to install. I have a 73, 4cyl. B that I have pulled other Bs out of Fla. with a tow bar & this car I have put 125,000 miles on it & I am very happy with. I use to pull the O/D trans. out on the V-8 project & put a T-5 or rover 5sp. in and thin I would take the O/D trans. to a car show & sell it AS IS, thisway it would be far enough away were I would NEVER have to look at it! I am building a78 B for my sister & I have sold the O/D & have put the 5sp. in, there is NO WAY I will keep a O/D in a car that I am going to keep. P.S. I have 3 other Bs that have over 300,000 each + a trailer hitch!!!!!!!!!

Oh yeah? You didn't seem to think the OD was too bad when you drove mine :) And I never heard you say I should pull the OD and put a 5-speed in...

Steve S Wrote:

Same old discussion.

I run OD in the race car and the MGC (both dead reliable) and a T5 in the Jamaican, so have what many offering comments probably do not - experience with both options. FWIW I agree with Steve - I prefer the OD box, though the 5 speed is also an excellent option.

Personally I think one is crazy for not wanting a T9 5 speed :) :) Just kidding. :)

Steve S Wrote:

Ok, when anyone reads my first reply, please change "slightly" to "possibly 33 pounds".

Considering it's dead weight in the center of the car, at the lowest possible point, I still don't see it as a significant weight savings on a road car.

Drive without shoes on and you can save another 2 pounds. ;)

Steve S Wrote:

Don't forget to factor in the rebuild of the free transmission. Otherwise it's an unfair comparison. A used but good factory gearbox can even be easily be found for free. For a few hundred dollars you can convert it to overdrive with a conversion kit. Fitting a late model gearbox to an early B isn't that much work either. You only need to bulge the tunnel in the starter area, and lengthen the opening in the tunnel cover a bit.

As for weight and non-originality, I don't believe that more than 2% of the active users on this forum would ever push their car to such a limit that 25-30 pounds of weight difference on a car would be felt. Lighter is lighter, I agree. But weight is not the main factor in most decisions the average M.G. owner makes.

For example I notice you have wire wheels on your MGA. Minilites would be far lighter and stronger, yet you choose wires (as do most MGA owners). The reasoning of "it isn't M.G." is quite valid in this respect. Aesthetics and driving feel are major parts of why many of us drive these cars. The feel and sound of the gearbox as it clacks through the gates is part of that experience and must be considered into the equation when deciding whether or not to modernize.

A 5-speed is a better piece of engineering, but it isn't the right choice for everyone nor is the original box at all fragile. Humans aren't rational creatures, obviously, or we wouldn't drive M.G.s at all! :)

After having replaced six 3 sync transmisions, one of them an OD version that was rebuilt twice in less than 500 miles and now with a 4 sync that jumps out of gear on deceleration, I ain't buying the crap about the MG boxes being durable. If you drive them in a parade maybe. If you drive them like a sports car that you just stole, fugetaboutit.

Your mileage may differ.

I have to think there is a better way.

Pete

Speedracer Wrote:

NOHOME Wrote:

Steve S Wrote:

Actually, other than winding them out in each gear, I treat them like they are made of toilet paper. Don't even dream about shifting down on a track without a double clutch or heel and toe. The inability of the boxes to survive track days is what drove me to retire the GT as a track day car. The three sync units seem to have an affinity for wearing out the layshaft and/or layshaft bearings. Most don't actually break, just get noisy to the point of not wanting to drive the car without ear plugs. The OD version went in spectacular fashion both times; oiling down the rear tires at the end of the back straight is exciting! That event convinced me to do the conversion to the 4 sync. Once again, the 4 sync has not "broke" since can still drive it, just developed an anoying habit of jumping out of gear on deceleration. The actual gears inside look like they belong in a truck. Replacements are in the $50-$100 dollar range, so that is a good thing.

I have never had a broken transmission in any other car that I have owned, and they have always been manual shifts.

Never owned a truck, just two seater sports cars and now a protege. Guess I need to buy a rabbit's foot!

Pete