Who's faster, Rare Bear or Precious Metal?

[gjs238]

Who's faster, Rare Bear or Precious Metal?

https://en.wikipedia.org/wiki/Precious_Metal_(aircraft)
https://en.wikipedia.org/wiki/Rare_Bear

 

[FLYBOYJ]

Rare Bear

 

[grampi]

They're actually probably pretty close, but I would also have to give the edge to Rare Bear, however, there are other Mustangs that are faster than Rare Bear...Voodoo and Strega are definitely faster, and Dago Red was the fastest unlimited ever.

 

[gjs238]

They're actually probably pretty close, but I would also have to give the edge to Rare Bear, however, there are other Mustangs that are faster than Rare Bear...Voodoo and Strega are definitely faster, and Dago Red was the fastest unlimited ever.

Interesting...Dago Red with a RR Merlin and 4-bladed Hamilton Standard is faster than Precious Metal with a RR Griffon and contra-rotating prop?

 

[drgondog]

yep

 

[FLYBOYJ]

Precious Metal is a neat aircraft if it stays glued together. No disrespect to the pilot or crew (I know Tom pretty well) but the aircraft has had it's issues over the years and even now has not shown in any way shape or form that it could remotely keep up with Rare Bear.

 

[Bad-Karma]

How did the F7f place in 2014? The website that has the results seems to be down or blocked at work.

 

[GregP]

La Patrona (F7F) finished first in Silver. He actually finished second, but the winner was bumped up into Gold, so he forfeited first place and raced in Gold.

According to Steve Hinton Jr, both Strega and Voodoo will make about 540 mph in a straight line. According to Stewart Dawson, Rare Bear will make about the same in a straight line.

I think a real straight and level race would be VERY close. Precious Metal isn't in that group as fas as speed goes.

Dago Red WAS ... but is not airworthy at this time. I've seen the inside of that engine while it was being repaired at Joe Yancey's shop and I seriously doubt it will be as strong as it was if and when it runs again. I'd have to see it fly and finish a race at competitive speeds to believe it would still be as fast as it used to be. The block was warped 7° and you would have to deck it to get it square again. Joe got the crankcase bore straight, I KNOW that much. I thought he decked it, too ... but the new owners might have stepped in before he got that done.

At one point, they showed up at the shop with a couple of Sherrifs Deputies and demanded the engine. Joe had started working on it for the previous owners and he told them all that when his work was paid for they could have the engine, and not a moment before that time. The two Deputies said they were going to take it right then and Joe said they were welcome to try ... provided they could find it first.

They looked around the shop and left. Joe laughed and said the bank had called and told him they were coming for it, and he moved the engine some 25 miles away where NOBODY would ever find it. About 2 months later, Lockwood showed up and wanted to pay 50 cents on the dollar. Joe said that he could wait until Lockwood could pay it all, and they'd NEVER locate the engine ever until then. Lockwood came back later with the money. Joe made a call and had the engine delivered to his shop within 2 hours time. It went away and I haven't heard about it since.

The new owners of Dago Red would have to tell you whether or not the engine was or will be reassembled as a racing engine. They COULD reassemble it more or less stock, or they could elect to go racing / set records with it. It is more FUN to set records and go racing, bit it DOES cost a lot of money. If they returned Dago Red to stock configuration, it would be worth more. Only the new owners know their intentions. It would take a lot to get Red back to stock, but it COULD be recouped from sale. If they elect to go racing, my bet would be they'll use another Merlin as the race mill and let the old one be the "get home" engine in a less-stressed lifestyle.

NOBODY flies to/from the races or flies around in anything like Strega or Voodoo using the race engine. They fly around on the "get home" engine and save the race engine for racing. Guys will fly the big radials around a bit at low speeds, but the super-tweaked Merlins don't really get slow-timed except during break-in after overhaul and again during the workup for Reno.

With the compression ratios in the race Merlins being so low, they don't really like to run at all except at higher boost. I think the plugs would foul if you ran them slowly for very long. Maybe not, but I have yet to see either Strega OR Voodoo fly to the race or home again on the race engine.

 

[Bad-Karma]

La Patrona (F7F) finished first in Silver. He actually finished second, but the winner was bumped up into Gold, so he forfeited first place and raced in Gold.

According to Steve Hinton Jr, both Strega and Voodoo will make about 540 mph in a straight line. According to Stewart Dawson, Rare Bear will make about the same in a straight line.

I think a real straight and level race would be VERY close. Precious Metal isn't in that group as fas as speed goes.

Dago Red WAS ... but is not airworthy at this time. I've seen the inside of that engine while it was being repaired at Joe Yancey's shop and I seriously doubt it will be as strong as it was if and when it runs again. I'd have to see it fly and finish a race at competitive speeds to believe it would still be as fast as it used to be. The block was warped 7° and you would have to deck it to get it square again. Joe got the crankcase bore straight, I KNOW that much. I thought he decked it, too ... but the new owners might have stepped in before he got that done.

At one point, they showed up at the shop with a couple of Sherrifs Deputies and demanded the engine. Joe had started working on it for the previous owners and he told them all that when his work was paid for they could have the engine, and not a moment before that time. The two Deputies said they were going to take it right then and Joe said they were welcome to try ... provided they could find it first.

They looked around the shop and left. Joe laughed and said the bank had called and told him they were coming for it, and he moved the engine some 25 miles away where NOBODY would ever find it. About 2 months later, Lockwood showed up and wanted to pay 50 cents on the dollar. Joe said that he could wait until Lockwood could pay it all, and they'd NEVER locate the engine ever until then. Lockwood came back later with the money. Joe made a call and had the engine delivered to his shop within 2 hours time. It went away and I haven't heard about it since.

The new owners of Dago Red would have to tell you whether or not the engine was or will be reassembled as a racing engine. They COULD reassemble it more or less stock, or they could elect to go racing / set records with it. It is more FUN to set records and go racing, bit it DOES cost a lot of money. If they returned Dago Red to stock configuration, it would be worth more. Only the new owners know their intentions. It would take a lot to get Red back to stock, but it COULD be recouped from sale. If they elect to go racing, my bet would be they'll use another Merlin as the race mill and let the old one be the "get home" engine in a less-stressed lifestyle.

NOBODY flies to/from the races or flies around in anything like Strega or Voodoo using the race engine. They fly around on the "get home" engine and save the race engine for racing. Guys will fly the big radials around a bit at low speeds, but the super-tweaked Merlins don't really get slow-timed except during break-in after overhaul and again during the workup for Reno.

With the compression ratios in the race Merlins being so low, they don't really like to run at all except at higher boost. I think the plugs would foul if you ran them slowly for very long. Maybe not, but I have yet to see either Strega OR Voodoo fly to the race or home again on the race engine.

Very interesting insight thank you. Any inside info as to what made dago red so fast? I'm sure a lot of that is proprietary information but figured maybe some general answers were out there.

I might try to visit the race this year and maybe double up with a visit to lake tahoe. Tickets seem to be so expensive from Charlotte though.

 

[grampi]

Very interesting insight thank you. Any inside info as to what made dago red so fast? I'm sure a lot of that is proprietary information but figured maybe some general answers were out there.

I might try to visit the race this year and maybe double up with a visit to lake tahoe. Tickets seem to be so expensive from Charlotte though.

It was the "Mouse" motors that made Dago so fast...unfortunately and sadly the builder of those engines has passed and as far as I know, he took his engine building secrets with him...I do believe there has been attempts to reverse engineer his engines, but I don't know if there's been any success in doing this...

 

[GregP]

The engine is the biggest factor as grampi said above. There are numerous small aerodynamic changes that help out, though,

One thing they did, and I THINK they were the first team to do so, was to take out all the side and down thrust in the engine mount and remove any aerodynamic corrections in the tail. That is the vertical tail on a P-51 is slightly canted to help with torque and everything on Dago Red is straight. They also profiled the wing (different airfoil with ... essentially .... Bondo).

Not suprisingly, Strega and Voodoo have these mods, too, along with the "standard mod" of installing a much smaller canopy. Taken together, all the power and modifications add up to some 120 mph faster than stock, with the aerodynamics owning about 20 - 25 mph or so, perhaps slightly more, of the gain; most of it is from the added power. The teams that run P-51-based racers KNOW how much is aero and how much is power because they mostly fly around on stock Merlin engines. All they really have to do to find out is run the stock engine in a stock airframe and make a full power run. Also, they can run the stock engine in the modified airframe and do a full power run. The the rest is horsepower. Both Strega and Voodoo have done both tests. The aerodynamics help and Voodoo is doing another mod right now. Stevo Hinton is working on some carbon fiber speed parts, but which parts they are stays with the team.

One of the geniuses of all Merlin mechanics was Dwight Thorne, and HIS engines were called "mouse motors" in honor of the Chevrolet "Rat motor" of hot-rodding fame. Dwight Thorne racing cams are a VERY hot commodity these days. Strega has one and so does Dago Red. Voodoo doesn't and has to turn a couple of hundred rpm faster to get equivalent power.

When I said that the existing Dago Red engine might not ever race again, I meant the block. The cams and rods most certainly WILL probably race again in a replica "mouse motor," probably built up by Mike Nixon of Vintage V-12's here in California. I say replica because Dwight Thorne passed away some years back, but his engines live on and are the most powerful Merlin-nased racing engines in the world.

They aren't really Merlins anymore after they get the full "mouse" treatment. They run Allison G-series rods and wrist pins, custom pistons, custom valves, Dwight Thorne camshafts, modern mags, transport heads, etc. The block is Merlin and the bearings are Merlin or even custom. The gears are mostly Merlin and that's about it. They run huge spray bars and have big ADI tanks. Some even featured boil-off oil coolers. Most of the racing propellers cannot ever be flown on stock airframes because they are shorter than the lower limit for airworthiness to delay the prop tips as much as possible from going supersonic at full rattle.

 

[gjs238]

Guess I expected more from the RR Griffon and contra-rotating prop (Precious Metal.)
But it seems there are other issues as well.

 

[GregP]

Precious Metal really doesn't look all that aerodynamicaly tweaked to me. Looks like a more or less stock P-51D with the Griffon and contra-props ... and not much else other than maybe the canopy canopy. I don't know if the wing is profiled or not. I have absolutely NO idea how much power it makes, but if there is anyone with some expertise in getting power from the Griffon, it is probably those guys ... they are RUNNING one, so they naturally get familiar with it. But familiar doesn't mean development. I suppose only THEY could tell us how much power it makes and I've never seen numbers from the team. We can estimate, but that's about it. They KNOW.

I've never seen any aerodynamic analysis of contra-prop verus regular prop on the same airframe and same power, so I can't tell you much about that at all. Maybe Bill can. I was never really all that interested in contra-props since almost NO fighters had them except a very few essentially unsuccessful designs had them.

All a contra-prop essentially does is help eliminate torque. Since all the race winners aren't having torque issues at takeoff by using only the power required to take off, the contra-prop really isn't needed and they'd probably be faster using a Griffon and 4 or 5 blade standard prop setup, modified for speed. I'd say that's the call of Mr. Thom Richard. They run a class team and are great guys, but the speed isn't there to be competitive in Unlimited Gold. It's sort of like Miss America ... a great team and a good, solid plane ... but not a Gold class front-runner.

I am still a fan of both. It's sort of like pulling for the Chicago Bears ...

 

[Bad-Karma]

The engine is the biggest factor as grampi said above. There are numerous small aerodynamic changes that help out, though,

One thing they did, and I THINK they were the first team to do so, was to take out all the side and down thrust in the engine mount and remove any aerodynamic corrections in the tail. That is the vertical tail on a P-51 is slightly canted to help with torque and everything on Dago Red is straight. They also profiled the wing (different airfoil with ... essentially .... Bondo).

Not suprisingly, Strega and Voodoo have these mods, too, along with the "standard mod" of installing a much smaller canopy. Taken together, all the power and modifications add up to some 120 mph faster than stock, with the aerodynamics owning about 20 - 25 mph or so, perhaps slightly more, of the gain; most of it is from the added power. The teams that run P-51-based racers KNOW how much is aero and how much is power because they mostly fly around on stock Merlin engines. All they really have to do to find out is run the stock engine in a stock airframe and make a full power run. Also, they can run the stock engine in the modified airframe and do a full power run. The the rest is horsepower. Both Strega and Voodoo have done both tests. The aerodynamics help and Voodoo is doing another mod right now. Stevo Hinton is working on some carbon fiber speed parts, but which parts they are stays with the team.

One of the geniuses of all Merlin mechanics was Dwight Thorne, and HIS engines were called "mouse motors" in honor of the Chevrolet "Rat motor" of hot-rodding fame. Dwight Thorne racing cams are a VERY hot commodity these days. Strega has one and so does Dago Red. Voodoo doesn't and has to turn a couple of hundred rpm faster to get equivalent power.

When I said that the existing Dago Red engine might not ever race again, I meant the block. The cams and rods most certainly WILL probably race again in a replica "mouse motor," probably built up by Mike Nixon of Vintage V-12's here in California. I say replica because Dwight Thorne passed away some years back, but his engines live on and are the most powerful Merlin-nased racing engines in the world.

They aren't really Merlins anymore after they get the full "mouse" treatment. They run Allison G-series rods and wrist pins, custom pistons, custom valves, Dwight Thorne camshafts, modern mags, transport heads, etc. The block is Merlin and the bearings are Merlin or even custom. The gears are mostly Merlin and that's about it. They run huge spray bars and have big ADI tanks. Some even featured boil-off oil coolers. Most of the racing propellers cannot ever be flown on stock airframes because they are shorter than the lower limit for airworthiness to delay the prop tips as much as possible from going supersonic at full rattle.

Precious Metal really doesn't look all that aerodynamicaly tweaked to me. Looks like a more or less stock P-51D with the Griffon and contra-props ... and not much else other than maybe the canopy canopy. I don't know if the wing is profiled or not. I have absolutely NO idea how much power it makes, but if there is anyone with some expertise in getting power from the Griffon, it is probably those guys ... they are RUNNING one, so they naturally get familiar with it. But familiar doesn't mean development. I suppose only THEY could tell us how much power it makes and I've never seen numbers from the team. We can estimate, but that's about it. They KNOW.

I've never seen any aerodynamic analysis of contra-prop verus regular prop on the same airframe and same power, so I can't tell you much about that at all. Maybe Bill can. I was never really all that interested in contra-props since almost NO fighters had them except a very few essentially unsuccessful designs had them.

All a contra-prop essentially does is help eliminate torque. Since all the race winners aren't having torque issues at takeoff by using only the power required to take off, the contra-prop really isn't needed and they'd probably be faster using a Griffon and 4 or 5 blade standard prop setup, modified for speed. I'd say that's the call of Mr. Thom Richard. They run a class team and are great guys, but the speed isn't there to be competitive in Unlimited Gold. It's sort of like Miss America ... a great team and a good, solid plane ... but not a Gold class front-runner.

I am still a fan of both. It's sort of like pulling for the Chicago Bears ...

Thank you very much for all of that information! As a muscle car guy I can really appreciate the work that goes into these engines. Not until recently did I fully appreciate how "Hot Rod" like fighter designers and mechanics were back then. I've always been interested in WWII aviation since listening to my Grandfather's stories of being a crew chief with the eighth as a kid but I find as time goes on I really get sucked in to all the little details and fall in love with WWII fighters all over again.

 

[GregP]

You are welcome, Karma.

It's sort of amazing to me. The kids these days think that the Japanese invented overhead cams and 4-valves per cylinder, and don't realize that the Allison V-1710 was designed in 1929 with these features. The Merlin was developed around that time (or slighty before or after) in the form of the R-engine,too. Just before the Germans took a world speed record, the British had "hot rodded" a Spitfire and were about to try it themselves. That Spitfire was a standard Mk I (K9834) that was aerodynamically modified and bumped up to 2,160 HP.

Here is a pic:

It featured a 4-bladed, fixed pitch propeller and was supposed to be fast at 420 mph or so, but not quite up to the new record of 469 mph set by the so-called Bf 109R ... which was really not related to the Bf 109 in any way whatsoever.

So hot-rodding was alive and well in the air just before WWII. Personally, I like the lines of the high-speed Spitfire a lot. It would be way cool to see a reproduction of it, but Spitfire Mk I airframes are so rare that nobody would consider modifying one these days and, as much as I'd like to see one, I wouldn't seriously consider doing it if I had a Spitfire Mk I personally. Still, it's fun to think of doing one.