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Article on R series engines in July TW

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  • 53k
    replied
    quote:Originally posted by jeryst

    But why did they offer a less performing engine when the trend was heading toward higher performing engines. Did the superchargers have so much trouble that Studebaker just wanted to eliminate them?
    FWIW, I think a little bit of the rationale was so Avanti owners could have an air conditioned high performance car (factory didn't do a/c on R-3s).



    Paul Johnson, Wild and Wonderful West Virginia. '64 Daytona Wagonaire, '64 Daytona convertible, '53 Commander Starliner, Museum R-4 engine, '62 Gravely Model L, '72 Gravely Model 430

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  • Thomas63R2
    replied
    Believe what you want about dyno figures - and beware that the dyno math correction factors have evolved over time. Other than Popular Hot Rodding magazine's "Engine Masters Challenge" we do not race dynos. The dragstrip is the ultimate dyno, just don't expect Ted Harbit results unless you are Ted Harbit! There are some fairly standard calculations factoring in the weight of the car and the trap speed mph to arrive at a power figure. For those who may wonder: excess wheel spin at launch obviously kills e.t., but usually has almost no effect on mph.

    Thomas

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  • rockne10
    replied
    I also believe dynoed HP will exceed advertised figures.
    "ALWAYS DELIVER MORE THAN YOU PROMISED."

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  • Dan White
    replied
    I believe that this allowed Studebakers to race in certain brackets that did not allow blown engines. Other makes also were using dual quads or three twos for high performance so this was a way to meet that challenge, although it really did not work out that way since so few actually sold. It is also interesting that this engine (R4) was really the first and only Studebaker engine to really make good use of the stout bottom end, which if I remember right was designed for (continuous not just blown) fairly high compression ratios back in the days of its development.

    Here is an interesting article on the only R4 factory Daytona made I believe.

    http://racingstudebakers.com/R4_page_2.htm

    Dan White
    64 R1 GT
    64 R2 GT

    Leave a comment:


  • jeryst
    replied
    But why did they offer a less performing engine when the trend was heading toward higher performing engines. Did the superchargers have so much trouble that Studebaker just wanted to eliminate them?

    Leave a comment:


  • 53k
    replied
    quote:Originally posted by jeryst

    As you go up the R-series, the engines become higher performance, until you get to the R4, which has much less HP than the R3. Why was that?
    Supercharging (R-3) boosts the horsepower considerably more than dual four-barrels (R-4). Both engines are basically the same except the R-4 had 12 to 1 compression and the two AFBs.

    Here are the specs for the two engines-




    Paul Johnson, Wild and Wonderful West Virginia. '64 Daytona Wagonaire, '64 Daytona convertible, '53 Commander Starliner, Museum R-4 engine, '62 Gravely Model L, '72 Gravely Model 430

    Leave a comment:


  • jeryst
    replied
    As you go up the R-series, the engines become higher performance, until you get to the R4, which has much less HP than the R3. Why was that?

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  • Thomas63R2
    replied
    HCN, I remember when you were having that engine rebuilt (even though technically it was a "new" engine) - I was glad that you wanted a realistic "stock" R3 engine build, rather than a modern tech knowledge max effort build. I remember that some people were disappointed with the final power. I was happy to see your results back up what Granatelli promised for power.

    Thomas

    Long time hot rodder
    Packrat junk collector
    '63 Avanti R2 4 speed

    Leave a comment:


  • HNCadet
    replied
    [quote]quote:Originally posted by Laemmle

    Where?...........at the flywheel or the rear end? makes a big difference.



    Originally posted by 53k

    FWIW, when Jon and Mike Myer finished going through the NOS R-3 I sold a couple years ago, they put it on a dyno. It produced 357 hp with the milder cam.
    At the flywheel........and with stock, non-ported R3 heads. With the Mondello porting, I believe the reported 400HP numbers are easily achievable.

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  • Laemmle
    replied
    Where?...........at the flywheel or the rear end? makes a big difference.



    quote:Originally posted by 53k

    FWIW, when Jon and Mike Myer finished going through the NOS R-3 I sold a couple years ago, they put it on a dyno. It produced 357 hp with the milder cam.



    Paul Johnson, Wild and Wonderful West Virginia. '64 Daytona Wagonaire, '64 Daytona convertible, '53 Commander Starliner, Museum R-4 engine, '62 Gravely Model L, '72 Gravely Model 430

    Leave a comment:


  • Thomas63R2
    replied
    The percentage of horsepower increase via supercharging is very related to the percentage of boost measured in atmoshperes of increased breathing via forced induction. There is some simple math to calculate the horsepower increase of a supercharger that will get you close to the technical engineer math: divide the observed manifold boost by 14.7 (one atmosphere), then add 1 and multiply this by the unboosted horsepower. For example an Avanti at 4.5 psi: 4.5/14.7 = .306 atmosphere boost, 1 + .306 = 1.306, then 1.306 x 225 horsepower = 293 horsepower ~ pretty close to the 289 or 290 horsepower figure most often quoted. The engineer math would factor in the horsepower drag of the supercharger at a certain boost level and othe inefficiencies.

    The lower the boost and performance level of the engine, the more accurate the simple math will be. On the other end of the scale I had built a BBC with a large D2-R ProCharger centrifugal supercharger. Naturally aspirated it was 481 horsepower. At the 16.9 psi achieved it theoretically would have been ~ 2.15 time the n/a power for 1,034 horsepower. The actual measured horsepower was 953. The 81 horsepower difference was the loss from mechanical friction, belts, etc., and heat energy loss from compressing air.

    Thomas

    Long time hot rodder
    Packrat junk collector
    '63 Avanti R2 4 speed

    Leave a comment:


  • BobPalma
    replied
    quote:Originally posted by monomaniac

    Paxton, in their literature of the day, used to print:
    the addition of a supercharger will add 40% horsepower
    to the rear wheels.
    There you have it, guys!

    'No sense paying all that money for an R2 and getting only 289 HP. According to Paxton, you could order a base 289 with 4-bbl carb, rated at 225 HP, add a Paxton Supercharger, and wind up with a 40% increase: 315 HP![:0]

    (Geeze, Art, I wonder why Studebaker didn't just do that to begin with and save all the development cost of the R-series engines, only to produce a puny 289 HP R2? [}] <GGG> ) BP

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  • monomaniac
    replied
    Paxton, in their literature of the day, used to print:
    the addition of a supercharger will add 40% horsepower
    to the rear wheels.

    Leave a comment:


  • 53k
    replied
    FWIW, when Jon and Mike Myer finished going through the NOS R-3 I sold a couple years ago, they put it on a dyno. It produced 357 hp with the milder cam.



    Paul Johnson, Wild and Wonderful West Virginia. '64 Daytona Wagonaire, '64 Daytona convertible, '53 Commander Starliner, Museum R-4 engine, '62 Gravely Model L, '72 Gravely Model 430

    Leave a comment:


  • studegary
    replied
    quote:Originally posted by jeryst

    In the co-operator, there is a very good explanation of the differences between the R-series engines, so I had a couple of questions.

    It says the the R-3 engine, with a supercharger and single 4-barrel carb put out 355 HP, but an R-4 with higher compression pistons, dual 4-barrels and no supercharger dropped to 280 HP. Does the removal of the supercharger really cause that much of a drop in HP in spite of the other performance modifications?

    How much HP does a supercharger add, with all other things being equal?

    How does a 57 GH engine compare to the R-series engines? Does it fall in there somewhere, or is it more of an R-0 engine from which the others were improved?
    I thought that an R3 was rated by Studebaker at 335 HP (not "355 HP").

    A general rule of thumb is that a good supercharger adds one-third to the horsepower.

    Other items already answered.

    Gary L.
    Wappinger, NY

    SDC member since 1968
    Studebaker enthusiast much longer

    Leave a comment:

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