Rare Bear Engine Rebuild

Discussion in 'Aviation' started by gumbyk, Jul 6, 2014.

  1. gumbyk

    gumbyk Well-Known Member

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  2. GregP

    GregP Well-Known Member

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    #2 GregP, Jul 6, 2014
    Last edited: Jul 10, 2014
    Thanks for the update! I hope Rod allows it to run Nitrous this year, so it can be competitve.

    Last time it WAS competitive, they ran Nitrous. They'd never confirm it, but the Nitrous truck always stopped by the pits shortly after the plane landed while Lyle owned and raced it. The exhaust also turned dirty brown in the last 2 - 3 laps ... so I have a STRONG suspicion they ran Nitrous Oxide ... or somethinhg delivered by a Nitrous Oxide truck.
     
  3. grampi

    grampi Member

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    It will need more than just No2 to be competitive with today's dominant Mustangs....even the fastest Rare Bear version ever wouldn't be able to run with the likes of Strega, Voodoo, Precious Metal, and Dago Red (when it was still in racing form)....team Rare Bear will need a miracle...
     
  4. vikingBerserker

    vikingBerserker Well-Known Member

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  5. GregP

    GregP Well-Known Member

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    #5 GregP, Jul 10, 2014
    Last edited: Jul 10, 2014
    Precious Metal looks very cool but has never gotten very close Rare Bear's speed.

    In 2013 Precious Metal ran 434.6 mph and Rare Bear, without NO2, ran 451.3 mph.

    The last time they were even close competitors was probably 1975, and the Bearcat that would become Rare Bear was still faster at that time.

    Dago Red will come back to life, but it seems to be happening very slowly with no estimated time for completion yet.
     
  6. gumbyk

    gumbyk Well-Known Member

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    Looking at the past results, Strega is the only P-51 to regularly beat Rare Bear.
     
  7. Koopernic

    Koopernic Active Member

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    The Grumman Bearcat was orginally built with the R-2800 while rare bear was upgraded to R-3350. Was the R-3350 supplied in a modular power egg that had reasonably chance of being interchanged with the R-2800. Perhaps Grumman designed to the bearcat to handle the Wright engine from the start.
     
  8. grampi

    grampi Member

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    Maybe regularly, but in recent years Rare Bear hasn't even been competitive, while the Mustangs just keep getting faster. Dago Red and Strega have both run over 500 MPH laps, with Dago holding the record at 507...something Rare Bear has never done. Voodoo and PM are also getting faster, I expect to see Voodoo running close to, or over 500 MPH this year as well....team Rare Bear is going to have to pull off some kind of miracle to run with these Mustangs...
     
  9. Koopernic

    Koopernic Active Member

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    Dago Red runs a boost of 75 psig or 150 inches of mercury. This is three times the Merlins authorised war time boost on 150PN. There is probably enough jet thrusting there to fly the aircraft quite fast without the propeller. I reckon there is at least 900lbs there.
     
  10. grampi

    grampi Member

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    There has also been talk of having to replace the current pace plane (a T-33) with something faster as it's pilot said he's really having to push the throttle hard to stay ahead of the pack, because the racers are getting to be so fast....
     
    • Dumb Dumb x 1
  11. GregP

    GregP Well-Known Member

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    The Bearcat was not designed for the R-3350 and Rare Bear is te only Bearcat to be so converted.

    I was there when Stevo Hinton ran a lap at 512+ mph, so 507 cannot be the lap record unless the course was changed from previous years before he ran that speed. Don't think so. I believe they changed it after the Jimmy Leeward crash in 2011 and Stevo's fast laps had been run on it.
     
  12. grampi

    grampi Member

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    Either way, the record is held by a Mustang...that would've been young Steve (Stevo) flying Strega....
     
  13. GregP

    GregP Well-Known Member

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    #13 GregP, Jul 12, 2014
    Last edited: Aug 18, 2014
    Just to set the record straight, no Mustang ever ran 150 inches for a full 8 laps. The racing engines based on the Merlin get geat-soaked and must be throtled back or they blow up in spectacular fashion. Unless someone is catching him, Stevo backs off every two laps or so. You can tell if you loo at the laps speeds during the final race.

    If he sets a fast lap of 515 and the average works out to 487, then obviously not all the laps were at full rattle.

    Rare Bear is the opposite, they start out slower and let everything get up in the green before opening it up in the last 4 laps. The exhaust used to get dirty brown in the last 2 laps, indicating Nitrous Oxide. So, if they manage to get more speed out of Rare Bear, it could get interesting. I know Rod Lewis isn't happy with the finishes since he acquired the plane. I think there is more speed in the airframe but it remains to be seen if there is enough to run in front again when the Mustangs don't break.

    I'd have to say the two favorites this year are Tiger Destefani and Stevo Hinton in no particualr order. Naturally, I'm pulling for Stevo, but Strega is every bit as fast. One thing going for Stevo and Voodoo this year is that I believe Stevo is building the engine himself. I think Stevo is the smoothest pilot out there. He makes very few if any altitude excusrions and flies a consistently smooth and steady line.

    Winning takes place in the off season when you prep the aircraft for the races. Stevo has been working on Voodoo since very soon after the last race, so I know it is well prepped. That takes nothing away from Tiger's efforts, but many of Team Strega's wins had a large dose of Stevo during race prep. Tiger certainly has people who know and can do it too, but Stevo's efforts sure gave Voodoo a dose of race-winning preparation.
     
  14. BKDYankee

    BKDYankee New Member

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    To the post that said that Grumman may have designed the F8F to accommodate the R-3350. Answer: NO . I have been to the Grumman Archives and gone through all the proposals and test reports from
    Pax River. There is no mention in any of the official documents of fitting a R-3350 to it. In 1945 -1946 the R-3350's in service were early BA series engines which did not put out the same HP as the later EA series engine which the Rare Bear
    engine is based upon. Early R-3350's as used by the B-29's, Connies etc were notoriously unreliable. The "-2" Bearcat had a -30W "E" Series engine which was essentially a "C" power section with a variable speed super charge set up and a "box" on top of the blower
    that was some sort of automatic engine control. Walt Ohlrich told me these "boxes" on the -30W were also prone to failure in a racing scenario (he went through a half dozen one year at Reno in the '70's) and it was just best to switch to the R-2800 CA or CB series which was really the ultimate refinement of the R-2800 with better cylinders, crank and PR-58E Carburetor. The Navy in 1946 to 49 was looking towards jets as the future of fighter development and not piston engined craft. To Greg: Yes, the Bear did use Nitrous in its fastest years. It would have been nice to put it on there along with the three bladed P3 prop but there is actually less time between Races as you would think. Additionally, our experience this year has been that later EA series 3350 parts are getting much harder to find in new old stock condition. Given the power settings desired, using old parts that are "good" may be ok for an airshow airplane but at the stresses of race power scenarios, it is not optimal. Nitrous with a fuel injection system would be the way to go to get the best hp but the prop issue is still there. More HP is useless unless you can convert it to thrust in an optimal fashion. It also depends on the politics of Reno which over the last two years have left many scratching their heads as to what to do. We are not NASCAR and Reno is the only venue. It is a hard decision to make to invest 100's of thousands to build a race engine and modify a race plane for a race that may not even occur. I am not certain what year it was but Skip Holm set the RACE SPEED record for an entire race I believe at 507 MPH. This was the average for the whole race not just one lap. Which is amazing since no one has a qualifying lap faster than 499. Skip once told me that he really thought that Dago Red was the fastest Mustang ever. I have heard Dago Red was tied up in legal woes and now is being converted back to stock as stock Mustangs are worth much more monetarily than racers. It should also be pointed out that I believe Tiger was involved with development of Dago Red with Frank Taylor back in the late 70's and Strega followed thereafter. Rare Bear in a straight line, at altitude can run well over 500. We did set a record of 528 over I believe a 3km run. We are over 500 in the straightaways on the race course but "g" forces in turns have kept us from having a race average of over 500 mph. BTW, the record that Skip made in Dago was only done ONCE to my knowledge and has not been done since.
     
  15. BKDYankee

    BKDYankee New Member

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    It should be pointed out that last year Voodoo was very close to "lunching" his engine as they did find considerable metal in it after the race, even with Strega trying to do a "Kentucky Derby" stretch run to catch him from behind as the only real threat.. It leads one to speculate what would have happened if Strega had a better post position and had been able to push Stevo real hard through the whole race. It is feasible, that neither could have finished without blowing an engine which could have lead to some
    interesting scenarios. Because of our fuel system and ignition issues our telemetry told us we were only making about 2700hp with RB in '13 and still able to average 450. Leads one to speculate that if we could get RB back
    up to the high 3000's in HP or more what could have be possible.
     
  16. grampi

    grampi Member

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    BKDYankee

    It's a shame Dago Red isn't still racing today...wasn't it using a "Mouse" motor when it ran 507 MPH in '03? I don't know why they don't build those motors anymore (I realize the person behind the mouse motors is now gone, or just doesn't build engines anymore), but I think reverse engineering could be done to build them again. Not only were those engines powerful, they were also reliable...something not many others have been able to do...about Rare Bear, do you know what version and/or HP rating the 3350 was when they set the time-to-climb record?
     
  17. GregP

    GregP Well-Known Member

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    #17 GregP, Aug 20, 2014
    Last edited: Aug 20, 2014
    Dwight Thorne died. The only plane I know currently running a true mouse motor is Strega. Voodoo's engine is close, but it doesn't have a Dwight Thorne racing cam set, so they have to turn a few extra RPM to make the same speed.

    The Dago Red guys may or may not have the parts anymore, When I worked for Joe Yancey, they brought over the engine block (just before it was sold) and had us look at it. The block was twisted 7° and we decked it and we also made a center rod cap since theirs was missing. Then they sold Dago Red and the new owners and the bank wanted the engine block back. We told the bank to go piss up a rope ... they could have it back when they paid for the services we had performed on it.

    The new owner showed up with the cops and we told him "good luck finding it!" Joe's shop at the time had over 130 engines in the hangars. He said, "you can have it back when you pay the bill." They looked around briefly and went away. It sat that way for 3 months and they finally came over with a check. We told him when the check cleared he could come back for the engine block and parts and they went away and came back 2 days later. Meanwhile we retrieved the parts and delivered them with some advice for them should they decide to run ir race it again based on what we saw inside. It needed to be line bored and we HAD the equipment to do it should they so desire.

    They took the block and left ... but if they try to run it again without line boring it, it'll self destruct unles SOMEONE does the job first. When the block twists 7° the main bearings get out of line by a small bit. Tht results in flexing the crankshaft on every revolution. I'm sure Joe Yancey can do it and probably so can Mike Nixon (we aren't sure) of Vintage V12's and maybe a few other people. I hope they get it flying again, but they seriously need to pay their bills before trying to go round up all the parts that are out for service / rebuild. People who work on these things don't do it for fun or for free.
     
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