Looking to put some very serious power in front of this gear box
What is it rated at?
Is there any mods like shot peening or nitriding that can be done to make it stronger like bigger input shafts diff gears etc
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Some have run sick horsepower thru the ZF transaxle with good luck, but it's expensive to fix or replace. Yes, there are upgrades as I understand it. What horsepower level are you thinking? I would call Lloyd at RBT Trans or Dennis Quella at Pantera Performance.
800HP min to about 1200HP
What is the difference from the 4 pin box to the 7 pin?
What is the difference from the 4 pin box to the 7 pin?
-1 =4 pin -2= 7 pin. It refers to the amount of bolts holding the bellhousing to the main case.
I think 750hp is about the practical limit for the ZF trans. It mostly depends on how abusive you to it.
Ron
I think 750hp is about the practical limit for the ZF trans. It mostly depends on how abusive you to it.
Ron
What other transmissions fit in this car?
I have seen the Audi box and its dimensions appear to be right
I have seen the Audi box and its dimensions appear to be right
From my point of view every aspect of the Pantera points to a sensible limit of about 500 bhp as a GT car (i.e. on street tires). 500 bhp was a lot of horsepower in the late sixties when the Pantera was designed, especially in the world of road racing and endurance racing. I don't know if there was a "goal" when the car was built, but certainly if they felt the car could stand up to 500 bhp the designers would have felt it was "state-of-the-art" in that time period (for instance, the 351C was designed as a 515 bhp @ 7000 rpm race motor). If an owner is going beyond 500 bhp they should plan on making substantial alterations.
What I have heard over and over again from people who have raced the Pantera is "The Pantera is a GT, not a race car". In other words the Pantera requires a lot of re-engineering to turn it into a competitive race car. If an owner is using the car in racing conditions they should plan on making substantial alterations too.
Lloyd Butfoy will guarantee his rebuilt ZF's to 550 ft/lbs of torque, he doesn't use a horsepower figure. I have heard of ZFs bolted to Big Block (500 cubic inch) crate engines spitting gears through the cases. If I remember properly, fourth gear needs direct lubrication at elevated horsepower. I think Ron nailed it pretty good, about 700 bhp is the limit I am aware of people reliably using the ZF in racing conditions. The ZF needs the gear oil circulated through a heat exchanger too when racing it.
But the transmission is only one aspect. Even if you replace the gearbox, there are other areas of the car that will need to be re-engineered. I can think of two at the moment:
The foot print of the Pantera radiator is good to about 500 to 550 horsepower according to Evans Cooling. Going above 500 bhp in a racing application means gutting the front of the car to fit a larger radiator.
The monocoque chassis structure needs reinforcement anytime you slip racing tires on the car, or when you increase the motors output. the rear suspension & engine substructure twists significantly, and the A pillars will try to detach themselves from the front fender/firewall. Up to 500 bhp the street cars do fairly well with the chassis braces sold by the Pantera vendors. Guys racing their Panteras with more than 500 bhp usually make substantial alterations to the chassis, such as installation of tube sub-structures, or tying the whole chassis together via an elaborate roll cage, etc.
-G
What I have heard over and over again from people who have raced the Pantera is "The Pantera is a GT, not a race car". In other words the Pantera requires a lot of re-engineering to turn it into a competitive race car. If an owner is using the car in racing conditions they should plan on making substantial alterations too.
Lloyd Butfoy will guarantee his rebuilt ZF's to 550 ft/lbs of torque, he doesn't use a horsepower figure. I have heard of ZFs bolted to Big Block (500 cubic inch) crate engines spitting gears through the cases. If I remember properly, fourth gear needs direct lubrication at elevated horsepower. I think Ron nailed it pretty good, about 700 bhp is the limit I am aware of people reliably using the ZF in racing conditions. The ZF needs the gear oil circulated through a heat exchanger too when racing it.
But the transmission is only one aspect. Even if you replace the gearbox, there are other areas of the car that will need to be re-engineered. I can think of two at the moment:
The foot print of the Pantera radiator is good to about 500 to 550 horsepower according to Evans Cooling. Going above 500 bhp in a racing application means gutting the front of the car to fit a larger radiator.
The monocoque chassis structure needs reinforcement anytime you slip racing tires on the car, or when you increase the motors output. the rear suspension & engine substructure twists significantly, and the A pillars will try to detach themselves from the front fender/firewall. Up to 500 bhp the street cars do fairly well with the chassis braces sold by the Pantera vendors. Guys racing their Panteras with more than 500 bhp usually make substantial alterations to the chassis, such as installation of tube sub-structures, or tying the whole chassis together via an elaborate roll cage, etc.
-G
Thanks for the detailed info
Many of things i had planned already
It will have a cage and re enforced rails where the engine mounts
Thicker radiator and additional oil cooler for the engine and gear box are also planned
I can see I may need to look at another box for this application as there is no point trying to make it stronger if its just not going to handle it
Many of things i had planned already
It will have a cage and re enforced rails where the engine mounts
Thicker radiator and additional oil cooler for the engine and gear box are also planned
I can see I may need to look at another box for this application as there is no point trying to make it stronger if its just not going to handle it
You'll be making major modifications to support the power you want.
There's a guy in Australia who went to a sequential transaxle. Major modifications are necessary to fit this style in the car, and it's significantly bigger/heavier. There are sequential transaxles that are capable of handling what you want from places like Mendeola, etc. The sequential kind of transaxles typically have dog-tooth synchronizers that are meant for racing and don't last very long according to Lloyd B. (RBT Trans). Most boxes from Audis or Porsches aren't that much better than the ZF in my personal opinion.
There's a guy in Australia who went to a sequential transaxle. Major modifications are necessary to fit this style in the car, and it's significantly bigger/heavier. There are sequential transaxles that are capable of handling what you want from places like Mendeola, etc. The sequential kind of transaxles typically have dog-tooth synchronizers that are meant for racing and don't last very long according to Lloyd B. (RBT Trans). Most boxes from Audis or Porsches aren't that much better than the ZF in my personal opinion.
quote:Originally posted by Malow:
800HP min to about 1200HP
What is the difference from the 4 pin box to the 7 pin?
The only box that has much of a reputation for tolerating these power levels is the Ricardo as used in the Ford GT. There are lots of examples of twin turbo conversion GTs and they can put down some big numbers. The Ricardo is much bigger and heavier by comaprison to the ZF and requires major structural mods to a Pantera to accomodate. If you search the site I believe you will find some info as one of the members was having one fitted his car by one of the West Coast vendors.
IMO, this is not a productive endeavor. If you want to be able to say you have a TT 1200 HP Pantera, you can certainly succeed; bring your wallet. However, you will never succeed in getting that power to the ground in a Pantera and after you install a Ricardo and all the overhead it takes to properly support a twin turbo set up you will have a very heavy car that is very rear biased in weight distribution. I don't mean to be a kill-joy but better to confront these facts now than having the realization after all the effort.
About the only use for such a Pantera is Texas mile or maybe open road racing though I still think lighter is better on the latter.
K
I sense a drag racing application... which is after all immense popular in Australia 
Ron has the power level about right for a ZF. L Butfoy can do a few things to help if you really need it; one owner famous as a brutal shifter in his 750 bhp race-Pantera regularly sheared teeth off gears during shifts, so RBT had some made from a much stronger type of steel. We probably don't want to know the cost... (He still breaks them). The later ZF cases used in the supercharged BMW M-1 are a good addition as they reinforce the differential and use heavier shafts, bigger bearings and other such upgrades that cannot (without massive rework) be installed in a 'std' ZF.
Another owner who does not bang-shift his car, successfully ran over 750 bhp thru a standard gearset and gearbox (except for the time when he flew a looong distance going over a bump at 220 mph and didn't shut off. Snapped the clutch input shaft like spaghetti on landing). Surprising how much driving style changes the requirements. Personally, 1200 hp in a Pantera is something I'd only watch. From a safe distance....
Another owner who does not bang-shift his car, successfully ran over 750 bhp thru a standard gearset and gearbox (except for the time when he flew a looong distance going over a bump at 220 mph and didn't shut off. Snapped the clutch input shaft like spaghetti on landing). Surprising how much driving style changes the requirements. Personally, 1200 hp in a Pantera is something I'd only watch. From a safe distance....
quote:Originally posted by Malow:
800HP min to about 1200HP
Here’s an example of a very well executed TT sbf with a Ricardo in a SPF GT40 replica. It’s been wrecked and will be for sale for a very long time at the asking price. The second link is a good read for anyone considering such a build in a Pantera.
Blaine Carmena (aka Pantera Turbo) has a very well done TT Pantera that he built with open road racing in mind. He uses a large air-air interccoler for sustained operation at boost. His build is definitely worth inquiry.
http://cgi.ebay.com/ebaymotors...&hash=item45fe454ce9
http://www.gt40s.com/forum/sup...ay-parts-spares.html
Best,
K
I am currently running in excess of 800HP and 800ft/lbs of torque at the tire on my car. I have pushed it to peak hp and torque in 5th gear with full traction and have had no issues. I have also drag raced launching fairly aggressively with with big sticky tires and have yet to break anything. Im not saying it will do this forever but I have had no issues yet.
quote:Originally posted by PanteraTurbo:
I am currently running in excess of 800HP and 800ft/lbs of torque at the tire on my car. I have pushed it to peak hp and torque in 5th gear with full traction and have had no issues. I have also drag raced launching fairly aggressively with with big sticky tires and have yet to break anything. Im not saying it will do this forever but I have had no issues yet.
What is your 1/4 mile time and trap speed?
I think of it this way. First, I let others blow it up, then let them decide, gee, I guess that was too much.
The Ford GT40 first had a Collati. It was still a Lola GT at that point until Ford bought the rights to the car.
You can research if you like but those cars all had DNF's in the early days due to transmission failures.
In the development of the car the race teams switched over to the ZF to handle the power of the 289 under race conditions.
On a good day, they could coax 400hp out of that 289, Webers, 180 degree bundle of snake headers and all.
In the continuing development of the car, the 427 was the next step in it's evolution.
By that time, Phil Remington was the engineer in charge for Ford. He is mentioned most often in association with Shelby but Ford had basically split the Mark I, 289's to Shelby and the 427's to Hoolman-Moody. No matter who is responsible for what now.
The ZF behind the 427 was inadequate. The 427 race engine with the aluminum heads, i.e., the "lightweight 427 was limited to a compression ration of no more then 10:1 and about 500hp and 550 ft-lbs of torque for durability reasons with the thin aluminum heads.
The 427 "lightweight" engine is an entirely different beast then the iron head versions. The aluminum heads are very thin and won't take more the 10:1 compression.
Remington designed and entirely different transaxle for it using the internals of the Ford "top loader" transmission to handle the power. It is a four speed.
The transaxle has an entirely different designation. Don't ask me, look it up if you are curious.
Where anyone today is saying the ZF today will handle 700 hp is beyond me?
What was is what is. It is a small block transmission and the 351c fits into that description.
500hp-ish is the expected capacity. If you look at the Gp4 factory race Panteras that is about what those engines were. No supercharges, no strokers, no nitrous. Webers yes, but in fact they are pretty much torque killers throughout much of the rpm range...except for one very, very narrow band when all Hell breaks loose with them.
Maybe today technology can make pigs fly but if you are running 1000hp in front of this thing the betting pool is open as to when and how far it is going to blow up.
Winston Churhill once said, "those that refuse to learn from history are doomed to repeat it".
Well said if you ask me. Gentlemen, care to place your bets?
The Ford GT40 first had a Collati. It was still a Lola GT at that point until Ford bought the rights to the car.
You can research if you like but those cars all had DNF's in the early days due to transmission failures.
In the development of the car the race teams switched over to the ZF to handle the power of the 289 under race conditions.
On a good day, they could coax 400hp out of that 289, Webers, 180 degree bundle of snake headers and all.
In the continuing development of the car, the 427 was the next step in it's evolution.
By that time, Phil Remington was the engineer in charge for Ford. He is mentioned most often in association with Shelby but Ford had basically split the Mark I, 289's to Shelby and the 427's to Hoolman-Moody. No matter who is responsible for what now.
The ZF behind the 427 was inadequate. The 427 race engine with the aluminum heads, i.e., the "lightweight 427 was limited to a compression ration of no more then 10:1 and about 500hp and 550 ft-lbs of torque for durability reasons with the thin aluminum heads.
The 427 "lightweight" engine is an entirely different beast then the iron head versions. The aluminum heads are very thin and won't take more the 10:1 compression.
Remington designed and entirely different transaxle for it using the internals of the Ford "top loader" transmission to handle the power. It is a four speed.
The transaxle has an entirely different designation. Don't ask me, look it up if you are curious.
Where anyone today is saying the ZF today will handle 700 hp is beyond me?
What was is what is. It is a small block transmission and the 351c fits into that description.
500hp-ish is the expected capacity. If you look at the Gp4 factory race Panteras that is about what those engines were. No supercharges, no strokers, no nitrous. Webers yes, but in fact they are pretty much torque killers throughout much of the rpm range...except for one very, very narrow band when all Hell breaks loose with them.
Maybe today technology can make pigs fly but if you are running 1000hp in front of this thing the betting pool is open as to when and how far it is going to blow up.
Winston Churhill once said, "those that refuse to learn from history are doomed to repeat it".
Well said if you ask me. Gentlemen, care to place your bets?
Sorry- you cannot compare 62-67 GT-40 ZFs with the later units used in passenger cars. Early ZFs used in GT-40s and a few Mangustas were physically smaller; the aluminum cases alone weigh 15 lbs less than the ones used 'upside-down' in Panteras. Two more bolts were added in the clutch area and one more in a slightly larger bolt circle on enlarged bellhousings. Early racing ZFs used aluminum side-plates which in an enduro-racing situation heated, expanded and relaxed differential side bearing preloads leading to "ZF trans failure". All Panteras and most Mangustas got ductile-iron side plates. I run a pair of the original racing aluminum side plates on the street (for a 12 lb weight loss) and they work fine in a street application.
I instrumented our ZF: it took over an hour of running on Nevada desert highways at way over the 70 MPH limit to get the ZF to barely 180F. Gt-40s and GR-4 Panteras needed tranny coolers and aux. pumps to allow the system to survive (300F) in 3 to 6 hr race conditions. And my setup is with a 'street' ZF using heat-producing clutches in the LSD; GT-40s used a one-way LSD similar to a Detroit Locker that heated the lube much less but was noisier & wore much faster.
There were at least a dozen high-powered BBC street conversions built in the '80s by Bonneville's Mike Cook; at least one is still running around So-Cal. Within the last dozen years, quite a few BBF conversions have been done by the Byars Bros; one street car has a 545 cube assembly with no ZF problems. He's run the Nevada Mile two years so far, trying to break 180 from a standing start after driving there from Nor-Cal and back. He's getting close. Several others have a 514s. One drove to 'Vegas from LA a few years ago and ran an open track event, then drove home- all with zero problems.
I could go on.... but experience shows that a 5DS-25/2 ZF WILL handle about 750 bhp ON THE STREET. It may NOT survive pro enduro racing although several real-racers currently run the 3hr-long Classic LeMans each year and one was clocked repeatedly at 195+ on the Mulsanne straight. Incidently, a Ricardo won't work in a Pantera unless you feel up to rebuilding the entire rear clip. The 210-lb, 1000-horse-rated Ricardo trans is 3" too wide to fit between the Pantera's frame rails, where the rear suspension attaches. I know of 1.0 Pantera running such a thing (with a Ford GT engine) and the installer said he never wanted to do another. A late Porsche turbo transaxle probably makes more sense than a Ricardo.
I instrumented our ZF: it took over an hour of running on Nevada desert highways at way over the 70 MPH limit to get the ZF to barely 180F. Gt-40s and GR-4 Panteras needed tranny coolers and aux. pumps to allow the system to survive (300F) in 3 to 6 hr race conditions. And my setup is with a 'street' ZF using heat-producing clutches in the LSD; GT-40s used a one-way LSD similar to a Detroit Locker that heated the lube much less but was noisier & wore much faster.
There were at least a dozen high-powered BBC street conversions built in the '80s by Bonneville's Mike Cook; at least one is still running around So-Cal. Within the last dozen years, quite a few BBF conversions have been done by the Byars Bros; one street car has a 545 cube assembly with no ZF problems. He's run the Nevada Mile two years so far, trying to break 180 from a standing start after driving there from Nor-Cal and back. He's getting close. Several others have a 514s. One drove to 'Vegas from LA a few years ago and ran an open track event, then drove home- all with zero problems.
I could go on.... but experience shows that a 5DS-25/2 ZF WILL handle about 750 bhp ON THE STREET. It may NOT survive pro enduro racing although several real-racers currently run the 3hr-long Classic LeMans each year and one was clocked repeatedly at 195+ on the Mulsanne straight. Incidently, a Ricardo won't work in a Pantera unless you feel up to rebuilding the entire rear clip. The 210-lb, 1000-horse-rated Ricardo trans is 3" too wide to fit between the Pantera's frame rails, where the rear suspension attaches. I know of 1.0 Pantera running such a thing (with a Ford GT engine) and the installer said he never wanted to do another. A late Porsche turbo transaxle probably makes more sense than a Ricardo.
... so, the ZF-1s used in the early panteras have the same smaller and lighter, but also weaker bellhousing/case combo as the GT-40s/mangustas??
quote:Originally posted by Push1267:
... so, the ZF-1s used in the early panteras have the same smaller and lighter, but also weaker bellhousing/case combo as the GT-40s/mangustas??
Yes. 4 bolts vs 7 bolts on a -2 .
Ron
This is all good to hear but I personally have never been so lucky.
I'm thinking of Rod Stewart singing, "some guys have all the luck, some guys have all the pain".
Of course the trick to success in racing, and we are talking about racing combinations here, is to run right to the ragged edge.
I truly wonder exactly how many of these ZF's are box stock?
Still comforting to know. I won't hesitate to hit it with my 250hp cheater nitrous system then? Well maybe not. I don't want to reinvent the clutch for this thing. But that's just me.
I'm thinking of Rod Stewart singing, "some guys have all the luck, some guys have all the pain".
Of course the trick to success in racing, and we are talking about racing combinations here, is to run right to the ragged edge.
I truly wonder exactly how many of these ZF's are box stock?
Still comforting to know. I won't hesitate to hit it with my 250hp cheater nitrous system then? Well maybe not. I don't want to reinvent the clutch for this thing. But that's just me.
Box-stock ZFs? Well, I'd guess that most are, since new spare parts (except for the 3 oil seals and side bearings) are almost non-existent and very complicated to install. There are no adjustments except thru selective parts selection and (scarce) steel shims. The only real variation might be switching ratios in the ring/pinion or possibly the 5th gear-pair for mileage or speed improvements, and those require total disassembly with specialized tools.
100% of new stock parts since the late '80s have come from Lloyd Butfoy of RBT whose father bought the name, manufacturing rights & all spares for the 5DS-25/2 transaxle from ZF. So either you buy salvaged parts or non-stock pieces from a number of vendors, or new parts, and all new parts will have come from RBT.
Incidently, even the gaskets are critical since their thickness controls backlash and preload, as well as whether they retain lube inside. I don't advise skimping on ANYTHING in this precision $7000 assembly! Lloyd is sometimes difficult to reach but is extremely knowlegable in all aspect of this transaxle; it's all he does since he was a kid. He's willing to talk but is extremely busy, so free advice and brain-picking is hard for us to do.
100% of new stock parts since the late '80s have come from Lloyd Butfoy of RBT whose father bought the name, manufacturing rights & all spares for the 5DS-25/2 transaxle from ZF. So either you buy salvaged parts or non-stock pieces from a number of vendors, or new parts, and all new parts will have come from RBT.
Incidently, even the gaskets are critical since their thickness controls backlash and preload, as well as whether they retain lube inside. I don't advise skimping on ANYTHING in this precision $7000 assembly! Lloyd is sometimes difficult to reach but is extremely knowlegable in all aspect of this transaxle; it's all he does since he was a kid. He's willing to talk but is extremely busy, so free advice and brain-picking is hard for us to do.
quote:... so, the ZF-1s used in early panteras have the same smaller and lighter, but also weaker bellhousing/case combo as the GT-40s/mangustas??
Yes- not all, but possibly your #1267 pushbutton. RBT refers to these transitional transaxles used in a few pushbutton Panteras as "dash- 1-1/2" assemblies, since they use a later Pantera 'dash-2' differential case in the upside-down configuration a Pantera chassis needs, with a flipped-over 'dash-1' Mangusta gearbox in the middle and a Pantera end-cap. A few still have the low 4.50:1 Mangusta gearing in the ring/pinion, in place of the 4.22:1 ring/pinion like later Panteras. This produces shattering acceleration but only 135 mph at 5500 rpms. Most US Panteras were changed by Ford under warranty and the fragile transitional ZFs scrapped.
Check the number of bolts holding the bellhousing onto your engine, and whether the bellhousing has two 'windows' or only one. Such 2-hole bellhousings were sand-cast so they're rough, while later units were die-cast and are smooth. Such early Pantera transmissions share the same problem as the Mangustas: an almost total lack of spare parts specific to this transmission, although Roland Jaeckel in Germany may still have a few parts. Please don't ever break anything!
quote:...I don't advise skimping on ANYTHING in this precision $7000 assembly! ...
Try $12k new, $7k minimum rebuilt for a ZF w/o a core. Yeah, they are painfully expensive.
How much abuse will the ZF stand?
Depends on two things: How much traction? How will it be driven?
If you run the car at Bonneville (VERY limited traction on the salt) the ZF will probably handle anything you can get in a Pantera.
Smokey burnouts at the dragstrip? Power shifting? I would guess 400-500hp will eventually break a transaxle.
If you can afford the service, then go for it!
Depends on two things: How much traction? How will it be driven?
If you run the car at Bonneville (VERY limited traction on the salt) the ZF will probably handle anything you can get in a Pantera.
Smokey burnouts at the dragstrip? Power shifting? I would guess 400-500hp will eventually break a transaxle.
If you can afford the service, then go for it!
That's right, Push-1267; you have one of those famous transitional ZFs. It's impossible to tell what parts are inside without total teardown, but the mainshaft on these ZFs was a little shorter and uses a steel extension for the pilot bushing. Later assemblies had a different length mainshaft & bellhousing, so a pilot extension was no longer needed. Changing a pilot bushing is a real exercise in these due to the design; I recently modified one for a Mangusta owner (same setup) so it's easier to R & R. Details in a PM if you're interested.
BTW- a tip to prevent potential breakage: leave out the bolts & cylindrical spacers that run at an angle from the bellhousing to the early side plates. These really don't do much bracing but do tend to loosen over time. Loose bolts have cracked one or both side plates in two, which leads to lubricant loss and much expense! A very few such sideplates were cast aluminum from the GT-40 program, but most were cast iron. They look identical but if they're magnetic, they're iron.
BTW- a tip to prevent potential breakage: leave out the bolts & cylindrical spacers that run at an angle from the bellhousing to the early side plates. These really don't do much bracing but do tend to loosen over time. Loose bolts have cracked one or both side plates in two, which leads to lubricant loss and much expense! A very few such sideplates were cast aluminum from the GT-40 program, but most were cast iron. They look identical but if they're magnetic, they're iron.
BTW, Push-1267; if you want to retain the 'stock' look in your engine bay, the right-angle fitting/dipstick on your transitional ZF will transfer directly to a dash-2 ZF and will still read correctly, as will the angle-bolted side plates (match the side-bearing shimming from whatever later model ZF you may locate). Sadly, the sand-cast bell housing won't fit unless you do some machine work on it to adapt it for the later, larger case dash-2 ZFs. But changing to a later box is definitely something that should be on your to-do list in the future. Call it insurance.