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R-3350 racers with a slow nose case?

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  • R-3350 racers with a slow nose case?

    Remind me. Which racers used the R-3350 EA-2 slow nose gear reduction case?

    Rare Bear
    September Fury
    Critical Mass
    Riff Raff

    Were there any others? Cornell's racer was going to have one but that went to Sept Fury. I'm pretty sure Mr. Awesome does not have one.

    Thanks,
    Bill Pearce

    Old Machine Press
    Blue Thunder Air Racing (in memoriam)

  • #2
    Re: R-3350 racers with a slow nose case?

    Riff Raff never used the slow speed nose case we got from Matt Jackson in the early 2000s. We ran a stock motor every year we raced. Owner Mike Keenum never pulled the trigger on building a race engine and eventually traded the case to Jeff Abbott for some engine work. Not sure what Jeff did with it from there. My guess is its in the Rare Bear inventory now.
    Ray

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    • #3
      Re: R-3350 racers with a slow nose case?

      Thank you for the info and corrections!
      Bill Pearce

      Old Machine Press
      Blue Thunder Air Racing (in memoriam)

      Comment


      • #4
        Re: R-3350 racers with a slow nose case?

        Originally posted by RiffRaffRay View Post
        Riff Raff never used the slow speed nose case we got from Matt Jackson in the early 2000s. We ran a stock motor every year we raced. Owner Mike Keenum never pulled the trigger on building a race engine and eventually traded the case to Jeff Abbott for some engine work. Not sure what Jeff did with it from there. My guess is its in the Rare Bear inventory now.
        Ray

        I believe Stew Dawson had one. Don't know if Rod ended up with it or not. Jeff Abbott used to be his engine man, I believe.

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        • #5
          Re: R-3350 racers with a slow nose case?

          Originally posted by toldjaso View Post
          I believe Stew Dawson had one. Don't know if Rod ended up with it or not. Jeff Abbott used to be his engine man, I believe.
          Any chance that the Neptune fire bombers that have just been retired had a slow nosecase? Or was that just in a certain model of the Constellations?

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          • #6
            Re: R-3350 racers with a slow nose case?

            Originally posted by dec View Post
            Any chance that the Neptune fire bombers that have just been retired had a slow nosecase? Or was that just in a certain model of the Constellations?
            I always heard that 16 aircraft (Super Connies?) were built with the slow-turning nosecases to fly over the polar icecap. I don't know of any others. I think most military aircraft had a spare set of engines as part of the contract, but not sure how many of these were ever produced.

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            • #7
              Re: R-3350 racers with a slow nose case?

              As far as I know, the slow nose case was used in the R-3350-988TC18EA-2 engine. Only 283 of these engines were built. The only application for these engines were the 44 L-1649 Starliners. The EA-2 has a .355 reduction, and other TC engines had a .4375 reduction.

              B-29 and B-32 engines did have a .35 reduction, but these were the early engines (A and B) that had some issues. Late/post war engines were the C-series, and almost all had a .4375 reduction. The nose cases are not interchangeable between A/B and later engines. Fifi had its engines switched over to the later C engines in 2010, and Doc also uses C engines. Well, both B-29s use components of various C-series engines to make their own hybrid engine. The TC engines are D and E series.
              Bill Pearce

              Old Machine Press
              Blue Thunder Air Racing (in memoriam)

              Comment


              • #8
                Re: R-3350 racers with a slow nose case?

                I believe Rod owns all of the complete slow nose cases with the exception of the ones that Lufthansa has for their Super Connie restoration.

                Comment


                • #9
                  Re: R-3350 racers with a slow nose case?

                  Originally posted by Race5 View Post
                  I believe Rod owns all of the complete slow nose cases with the exception of the ones that Lufthansa has for their Super Connie restoration.
                  And some of those (Rod's) are not very cherry
                  Last edited by toldjaso; 11-01-2017, 03:54 PM.

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                  • #10
                    Re: R-3350 racers with a slow nose case?

                    Where did the ones from the other 2 surviving Super Connie's go?
                    Reno from '99 to '22

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                    • #11
                      Re: R-3350 racers with a slow nose case?

                      Just curious. If you put the R-3350 EA-2 slow nose gear reduction case on a relatively stock Sea Fury such as Sawbones, how much would the Reno lap speeds increase? Sawbones seems to be stuck around 420 mph in qualifying. Would the slow nose case get them significantly faster without any other air frame mods?

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                      • #12
                        Re: R-3350 racers with a slow nose case?

                        Originally posted by Ken Adkins View Post
                        Just curious. If you put the R-3350 EA-2 slow nose gear reduction case on a relatively stock Sea Fury such as Sawbones, how much would the Reno lap speeds increase? Sawbones seems to be stuck around 420 mph in qualifying. Would the slow nose case get them significantly faster without any other air frame mods?
                        My take on it is that an aircraft may not gain any speed with just adding a slow nose case. If the engine is built, then the standard .4375 gear reduction becomes a limiting factor, and that is when switching to a slow nose case can make "faster" happen. A stock R-3350 probably would not benefit from the lower reduction.

                        It is all about keeping the propeller tips below supersonic. Let’s say that the perfect speed for the prop is 1,200 rpm. At that propeller speed, an engine with a .4375 reduction would run at 2,743 rpm, around max for a stock R-3350. But, if you have modified your R-3350 to make more power and you wanted to turn the engine faster, you are limited by the gear reduction because you must keep the prop at or below 1,200 rpm. Switching to a slow nose case with a .355 reduction allows you to keep the prop at 1,200 rpm, but the engine will now run at 3,380 rpm (23% higher rpm). An engine speed of 3,380 rpm is probably too fast for an unmodified R-3350, but that rpm may be ideal for one that is hand-built by people who know what they are doing.

                        As RiffRaffRay was saying, Keenum acquired a .355 slow nose case but never used it on Race 99 because they never had a full-on race engine. The .4375 reduction was working fine for the power they had and the engine rpm they were running (this last sentence is me hypothesizing).
                        Bill Pearce

                        Old Machine Press
                        Blue Thunder Air Racing (in memoriam)

                        Comment


                        • #13
                          Re: R-3350 racers with a slow nose case?

                          Bill,
                          You are correct, on a stock motor the slow speed nose case won't help. We had tuned our motor to run what the Wright 3350 manual had specified as METO power. Alot of work was done with the carb jets and fuel flow as well as ADI settings. The most speed we gained was from drag reduction i.e. exhaust pipe angles, custom canopy and windscreen, gear door adjusments, wing and fuselage profiling. Kerch was a huge help with this. He sent me an engineering study done by Hawker in the late 40's. They were trying to break the world speed record for a prop plane and were looking at airframe modifications. It showed each mod and the amount of speed that was gained. We went from 376 in 1998 to 446 in 2009 using 2 stock motors from Aircraft Cylinder. Our crew cheif Jim Skinner did the best he could with the plane considering Mike also used the airplane for airshows and cross country flights.
                          Ray

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                          • #14
                            Re: R-3350 racers with a slow nose case?

                            Originally posted by W J Pearce View Post
                            My take on it is that an aircraft may not gain any speed with just adding a slow nose case. If the engine is built, then the standard .4375 gear reduction becomes a limiting factor, and that is when switching to a slow nose case can make "faster" happen. A stock R-3350 probably would not benefit from the lower reduction.

                            It is all about keeping the propeller tips below supersonic. Let’s say that the perfect speed for the prop is 1,200 rpm. At that propeller speed, an engine with a .4375 reduction would run at 2,743 rpm, around max for a stock R-3350. But, if you have modified your R-3350 to make more power and you wanted to turn the engine faster, you are limited by the gear reduction because you must keep the prop at or below 1,200 rpm. Switching to a slow nose case with a .355 reduction allows you to keep the prop at 1,200 rpm, but the engine will now run at 3,380 rpm (23% higher rpm). An engine speed of 3,380 rpm is probably too fast for an unmodified R-3350, but that rpm may be ideal for one that is hand-built by people who know what they are doing.

                            As RiffRaffRay was saying, Keenum acquired a .355 slow nose case but never used it on Race 99 because they never had a full-on race engine. The .4375 reduction was working fine for the power they had and the engine rpm they were running (this last sentence is me hypothesizing).

                            At 3200 RPM, the cooling fins on the top of the forged aluminum cylinder heads on the R-3350 get distorted and warped out of shape. I always took this as a sign that the head was about to be breached.
                            As I recall, Curtiss Wright also said to scrap the whole engine if it hit this RPM or more. The big radials do not like high RPM!
                            And yes, it is a Hemi.
                            Last edited by toldjaso; 11-02-2017, 06:29 PM.

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                            • #15
                              Re: R-3350 racers with a slow nose case?

                              Thanks for the info!
                              Bill Pearce

                              Old Machine Press
                              Blue Thunder Air Racing (in memoriam)

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