Borg Warner T10 vs Toploader

[CompClassics]

GM gear sets probably came from 409 or Corvette applications if they were used, the book below references gear sets sourced from Pontiacs. The book I have was printed in period (circa 1964) that was authored by Bill Carrol. There are gear ratios referenced in this book also.
I have an early cast iron T10 that belongs to a 20XX Cobra that I am restoring, maybe I'll pull the side cover and check the ratios.

[CompClassics]

I am not so certain a "M" gear set would have been available in a 1962 Cobra. "M" gearsets were developed later and became the standard gear set for GT350 Mustangs in both the aluminum (early) case and iron (late) case T10 transmissions.

As per the steciling, I have only seen int on the iron case transmissions, maybe I missed it somewhere? I have seen C3AE and some letter. stenciled on iron transmissions.

[Dan Case]

Originally Posted by CompClassics

As per the steciling, I have only seen int on the iron case transmissions, maybe I missed it somewhere? I have seen C3AE and some letter. stenciled on iron transmissions.

1+ Iron case Ford production T10s in Cobras had color codes and stenciled numbers. The aluminum T10 cases were complete bare.

[peterpjb]

for my clarification, toploader were never installed in 289 Cobras in the first place?

does that also mean they are not FIA legal?

and are T10 with iron case FIA legal?

[1795]

How would you compare the T10 to the Toploader regarding performance and longevity? From my understanding there are very few T10's out there and that they are rather expensive.

[jon@harrison.ne]

Based on my experience I think anyone considering using a T 10 that might need rebuilding, or any new internal parts, should first find a shop that you were pretty sure could do the job and had the parts to do it. When I built my slabside about 17 years ago I had the T 10 worked on four times before I found a fellow in the San Diego area that knew what he was doing and it finally was perfect. The first rebuild had the input shaft barely engaging the pilot bearing (wrong part obviously). The shop that did the work took it all apart and that problem was solved but a couple more were created- bad gear noise and wrong speedo drive gear. Had more work done at another shop and it was still bad. Third time was a charm. Seems like there was a shortage of good parts, especially matching gearsets, back then and I have a feeling that the situation is even worse now.

[Dan Case]

Originally Posted by 1795

How would you compare the T10 to the Toploader regarding performance and longevity? From my understanding there are very few T10's out there and that they are rather expensive.

Ford units are much more robust than the Borg-Warner ones. Ford units that have the same physical installation dimensions as the T10s used in Cobras are not real common anymore. Like most 1960s parts used parts dealers COULD HAVE saved, they are not something desired by 1965 and later Mustang owners so there was no big demand to save them from the scrap heap.

Genuine production aluminum case transmissions as Cobras used are quite expensive as cores that can be rebuilt. Old cases with new old stock internals are insanely costly as the vintage racers have used up most of the available spares since vintage racing started in the mid 1970s. I inquired about a set of M gears in new old stock condition. The place didn’t have an input but all the rest was priced at nearly $6,000 delivered. I didn’t buy what they had because I didn’t have an idea where I would find a new old stock input to complete the set. The spare ex-Cobra transmission I bought cost almost twice as much as the original ex-Cobra engine I bought for a spare also. There are more than a few broken units scattered around in various Cobra owner garages.

Before leaving availability of original Cobra correct aluminum cased T10s, if the original Cobra owner is picky and wants a transmission date correct for their car then their hunt for a ‘correct’ assembly just became enormously harder. Production assemblies had a date of assembly stamped into them.

Ford ‘top loader’ transmissions (not ones somebody cobbled up and you have to get the matching shifter and linkage system also) that ‘bolt in’ to an original Cobra are not cheap as compared to let’s say a Mustang model.

[Dan Case]

Originally Posted by peterpjb

for my clarification, toploader were never installed in 289 Cobras in the first place?

does that also mean they are not FIA legal?

and are T10 with iron case FIA legal?

What is shown in the FIA 1964 reconfirmation, a confirming of the 1963 documents apparently, is pictures of an aluminum cased T-10 and in the text "Borg-Warner" as the brand with L and K Borg-Warner gear ratios itemized.

All I know of is up to that last street cars and works racers were Borg-Warner transmissions. That is all you can view in the Ford archives too.

[CompClassics]

Aluminum T10L cases were reproduced as were the T10M cases, I am not certain if they are still available. T10L and T10M gear sets can be found but as you stated can get expensive. That being said you can always use GM or other manufacturer gearsets, some have more desirable ratios than the Ford specific gear ratios and have a custom clutch disc made, most performance clutch manufacturers offer this service. Updated internal parts are available for the early T10 transmissions to help overcome their week points like popping out of gear (one of the biggest issues). These parts come from the Super T10 which became widely popular in the 70s and 80s for performance applications. You need to locate a Galaxie T10B iron case and tail shaft as this will provide the correct, transmission length, shifter position and mounting. The shifter assemblies can sometimes be an issue to find a rebuildable unit but you can use an aftermarket (Hurst) assembly also. Another issue the factory shifter unit has is the cross pin is smaller on the T10 shifters vs the Top Loaders shifter assembly which uses a larger diameter cross pin, I have swapped out the shifter boxes from the Top Loader to my T10, since Ford made both shifter assemblies they used the same mounting bolt patterns on both. You can put together a Ford Top Loader transmission assembly to bolt in place of a factory T10 transmission too if you desire. The T10 shifting is much smoother than the Top Loader in my opinion.
you might want to check out Richmound Gear, they bought the Borg Warner T10 design and still produce the transmission mostly for racing applications. There are other companies that also produce racing transmissions that utilize the T10 architecture and use such materials as magnesium for the cases. The B Production 289 Kirkham Cobra that we are currently putting together in our shop utilizes one of these hybrid T10 transmissions.

[MAStuart]

Some people can brake anything. My 1965 mustang came with a iron T10 289 2 barrel carb . Added lots of power including nitrous. Lots of street use and dragstrip use on slicks. Never broke it. Bought a new Richmond gear 5 speed. Broke it the first pass. Box it came in said bullet proof transmission.

The 1963 galaxie T10 that comes behind a 390 had a shorter input shaft than one from a 289. A 390 tranny can be used with a longer pilot bearing.

Galaxie T10's are cheep if you look in the right places. I just saw a couple in the last month for $200 or less. Guys that specialize in trannys think they have gold bars in them. I am talking iron cases not light weight galaxie transmissions.

Here is an iron one.

[Dan Case]

Originally Posted by CompClassics

The T10 shifting is much smoother than the Top Loader in my opinion.

+1 My opinion also. When everything is meeting OEM specifications T10 shifting is extremely smooth. I had a 1965 GT350 and a 1966 GT350 with T10s, 1969 and a 1970 Boss 302 with Ford top loader, and a 1970 Boss 429 with an enormously heavy version of top loader. With all cars adjusted to OEM specifications I like the gear changing ease and feel in the T10s best.

[xb-60]

Interesting comments from Jon and Dan.
I considered (but only for a short time) using a T10 for my FIA replica build, but rejected that path early, deciding on the Toploader.
Rationale for going Toploader rather than T10 was….
1. In Australia, Toploaders are available (while not exactly plentiful), but T10 gearboxes are rare. If I had chosen to use a T10, I would almost certainly have had to import one from US.
2. One of the very few David Kee agents is virtually just around the corner from me. T10 experts – as logic would suggest - are even more rare here than T10’s.
3. I wanted a period correct gearbox and the research I did at the time suggested that the Toploader is a very robust gearbox. As well, they were of course consequently used (in modified form) behind the Cobra 427, and used as the basis for the GT40’s Kar Kraft gearbox.

As far as shift action goes, my rebuilt Toploader and Hurst shifter has an action that feels similar (from distant recollection) to the bolt action on a Lee Enfield 303. If the T10 is better, it must be very good.

Cheers,
Glen

[1795]

Glen,

Glad to hear that your top loader shifts well. Cannot wait to give mine a try. A T10 would put me out of budget and probably be hind schedule as well. If you have any video of you driving your cobra I would like to see and hear it.
Take care

Jim

[ALF]

Many thanks for this great information!

I got curios about the difference between the T10-B (mentioned by John) and the T10-H (I own) main cases. I found an interesting pdf on the internet which contains some information I’m not able to verify/confirm.


Ford T10s used two iron main case configurations and both main cases are 9 1/2 inches long. The early, narrow transmission mounting bolt pattern T10 B-1 case was used from 1960-64 with 221/260/289 engines that had 5 bolt blocks and the later T10 H-1 case with a dual mounting bolt pattern entered service in late 1964 for use with the 289 and later engines with a 6 bolt block
http://wasaac.org/techdocs/T10.pdf

[xb-60]

Originally Posted by 1795

.....Glad to hear that your top loader shifts well. Cannot wait to give mine a try. A T10 would put me out of budget and probably be hind schedule as well. If you have any video of you driving your cobra I would like to see and hear it

Jim,

My "shifting" up to this point is on the bench, but indicates a satisfying setup. A video is some time off yet, but looking forward to the time when I can provide one. Good luck with your transmission ....but it seems that you would need more luck and cash if you had gone the T10 route

Cheers,
Glen

[jon@harrison.ne]

I am a bit puzzled hearing that the T 10 would just barely take the torque of a 271 HP 289. I bought a 65 Mustang K code, with a toploader, new off the lot and that engine never seemed very torquey to me. I remember seeing a 62 Chevy Impala 409/409 right off the showroom floor at the strip and you could see daylight under the front wheels after the flag dropped. How in the heck did the T 10 take that kind of torque? The car came back week after week, and beat everything.

[CompClassics]

As ALF brought reference to;
The transition from the narrow bolt pattern to the wide bolt pattern. This transition happened to both the T10 and the Ford Top Loader. The wide pattern Top Loader usually included both narrow and wide bolt patterns. This transition happened at the same time that the 289 engine switched from being a 5-bolt (used on all manual shift 260/289 Cobras) to the 6-bolt configuration. The 6-bolt configuration 289 engine was used on 289 Cobras that were equipped with automatic transmissions.

[CompClassics]

T10 transmissions have been installed in nearly all the major auto manufactures most powerful big block powered manually shifted drag cars, 409s GM, 421 Pontiac, 406-427 Ford & Mercury. Yes, evolution within each manufacturer may have lead to each manufacturer developing their own transmissions or the development of improved transmissions but the simple fact remains, the T10 transmissions had been backing some of the most brutal engines built in some of the biggest cars built at the time.

[Dan Case]

Originally Posted by CompClassics

T10 transmissions have been installed in nearly all the major auto manufactures most powerful big block powered manually shifted drag cars, 409s GM, 421 Pontiac, 406-427 Ford & Mercury. Yes, evolution within each manufacturer may have lead to each manufacturer developing their own transmissions or the development of improved transmissions but the simple fact remains, the T10 transmissions had been backing some of the most brutal engines built in some of the biggest cars built at the time.

Very true but tire technology back then was very primitive as compared to now. The very best racing tires 1960-70 were not as good as the tires a typical entry level economy sedan gets now. My 2015 F150 truck has “better” tires than my 1970 Boss 302 and 429 Mustangs had. Relatively skinny relatively hard rubber compound tires of the 1960s didn’t “hook up” all that well and 1960s cars didn’t have computer controlled engine, traction, and handling management.
The people that I knew or knew of that drag raced Cobras before they got too valuable didn’t want to get traction too soon. If they hooked up too soon something was going to break including drive shafts, clutches, transmissions, half shafts, and rear hubs. The person I was most impressed with ran Cobras and 427 Cobras. He barely spun a tire as he left the line. He was very quick still but was easy on the original drive trains.

Original street Cobras weren’t engineered for super high torque engines and high traction wide tires. SAI increased the load capacity of all most everything that rotated in their race cars. Ted Halibrand and other suppliers provided higher strength and higher fatigue resistant parts to SAI that just anybody could not go buy at their dealer’s parts department. Even with upgraded parts T-10s were not as tough as some users. If you have read a lot of SAI racing history you will come across tales of some drivers being very rough on transmissions while others didn’t have any problems

[peterpjb]

did SAI change the racing T10-L from long tail shaft to short tail shaft due to problems with the power train or was it the other way round?