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Motors gas guzzling coupes

Discussion in 'General' started by VCS2600, 15 May 2005.

  1. VCS2600

    VCS2600 What's a Dremel?

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    Big, big coupes. Feel the power, be bold! Efficiency? Meh, time to guzzle! :D

    1973 Grand Am
    [​IMG]

    1975 455 HO Grand Prix SJ

    77' Can Am W72 400
    [​IMG]
     
  2. jaguarking11

    jaguarking11 Peterbilt-strong

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    100hp/litre is a good judjing point for a sport car but the larger blocks have truble breathing to produce 100hp/litre. Like the 350 can deliver over 600hp/litre if forced induction is applied but the heads and the pure size of the motor impedes proper breathing to produce 100hp/litre. And the v-shape of the motor itself dosent allow mutch headroom. I supose you could run two diferent intake manifols and have the motor have two separate intake points. or even better 8 separate intake points like older race cars with independent carbs.

    But forced induction is not always as drastic as people think. On a larger motor forced induction can be put on with a totaly stock motor and still get good results as long as you dont put more than 10-15psi depending on the motor.

    Btw are there any naturaly aspirated diesels that run at or over 100hp per litre naturaly aspirated? I havent seen any but im shure somewere there had to be one or maybe even a production model.
     
  3. VCS2600

    VCS2600 What's a Dremel?

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  4. penski

    penski BodMod

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    Question: is it only American V-engines which use a single central carb or throttle body? It's a very, very rare practice in Europe. Even the Rover (old buick design) V8 used twin SUs (one manifold/carb per bank) for the majority of it's production life....

    Common practice here is one throttle body for a normal 4 pot, 2 for a sports 4pot 1 per bank on a v6, 2 per bank on a v8 and a bajillion on av12.

    *n
     
  5. Dad

    Dad You talkin to me?

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    As far as I know, that's true, but only in theory. I'm not sure about throttle bodies, but carbs have multiple barrels. For instance, a single carb will have at least 1 barrel for each bank of cylindars. So if it's a stock V-6, the carb will be called a 2-barrel carb. On high-performance cars, the carb will have 4-barrels or 1 for each pair of cylindars on a V-8. On inline engines, most likely the carb will only have a single large barrel. There are also manafolds where you can add multiple carbs so each cylindar has it's own barrel.

    Actually, if you look at a carberator off of a pure European car and compare it with an American carb, you'll see that the Euro carb is much smaller. This is because the American carb has multiple barrels. ;)

    www.edelbrock.com has in my opinion the best performance carbs anywhere and has a lot of information on their website about this stuff.
     
    Last edited: 8 Jun 2005
  6. dagamore

    dagamore What's a Dremel?

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    I also dont like the 100hp/1l rule as a sports car.

    I used to own (it died a painful death that involved 155mph a curve a wet road a big oak tree and 6 months in a wheel chair) 1972 Merc Cougar GT that I put in a 427 FE Side oilier, that made somewhere in the neighbor hood of ~600HP at the wheel. Now you might say how do I say ~600 simple the dyno I went to topped out at 550 HP and it went past that, and if you did the Weight/ 1/4 mile time math for (i.e. HP=weightx(velocity/234)^3) ~617=3010lb(with driver)x(138/234^3)I came out with a best HP of 617Hp. but even at 617hp with a 7l block that gives me only 88.1 HP/1l. and every one that ever drove/road in that car said/felt that it had way too much power. I loved that car. Nothing like a NA big block that idles at 485rpm to eat up Camaros and Vets even though I have more then 1000lbs of curb eight on them! and no my Cougar was not just a straight line car, it could turn left and right it even had a reveres gear on it.
     
  7. penski

    penski BodMod

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    Throttle bodies + EFi > Carbs

    I know that you guys tend to go for multi-barrel carbs but isn't that a terribly inefficient way of going about things? You'll get varying inlet tracts and (as a result), lower power than you could...

    *n
     
  8. Dad

    Dad You talkin to me?

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    Nah, not really. If you look at the multiple barrel manafolds, with the exception of a high-rise manafold, you'll see that each barrel pair is seperated and independent of each other. This way there is only a single linkage between the throttle/butterfly and the throttle cable/accelerator pedal.
     
  9. jaguarking11

    jaguarking11 Peterbilt-strong

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    Well in the older days they used to make some large intake manifolds that used huge 2inch or more wood spacers between the carb and intake for heat purposes and they used to develop about 100hp/L that way. Like I said v engines here have truble breathing, but I think its also down to restriction from polution standards.

    EDIT: I looked at the edelbrock list and I have to say those parts are good but not gr8. When it comes to intakes I agree with british designs. an intake per cylinder is optimal.

    Oh and btw around here carb=cheep hp.
     
  10. Dad

    Dad You talkin to me?

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    I have to respectfully disagree with that. I think any benefit gained is off-set with mechanical problems with that many more parts that need to work togeather. Imagine having to tune 8 single-barrel carbs to work exactly the same and consistantly!
     
  11. Froggy

    Froggy What's a Dremel?

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    n00b question for you brits: Are new cars still for sale in the UK that use a carb? just wondering because in the US, the last production car with a carb was some Subaru and i think it was 91 that they finaly switched it to fuel injection.
    Remember that changes to cars tend to happen on a world wide scale. Your cars are alot safer now then they were years ago because of the constantly changing saftey requirements here in the US. For example, in parts of euroupe, there is a new law requireing that there be at least 4" of clearance between the hood and anything hard, like the engine. Over the next few years it will cause cars elsewhere in the world to have the clearance, even tho its not required in those areas.
     
  12. VCS2600

    VCS2600 What's a Dremel?

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    1971 SS 454 Chevelle, 1 x 4bbl 7.4 liter V8! :naughty:

    [​IMG]
     
  13. Froggy

    Froggy What's a Dremel?

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    :jawdrop: :drool:
     
  14. :: Phat ::

    :: Phat :: Oooh shakalaka!

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    I think Europe's main gripe with American car's is the tendancy just to throw a big engine in there cos it was easy, not only this, but Americans are now used to these huge engines (what different do most of you know?)

    EU is just in a major gripe because our fuel costs are stupidly high compared to the US.

    Oh, and btw, My M Roadster has 3.2 pumping out 321+BHP (Its all down to the twin variable timing chains.)
     
  15. Dad

    Dad You talkin to me?

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    It's not because it's easy. I've said this a thousand times before, and I'll say it again: Larger displacement engines produce more torque than smaller displacement engines. It's not all about horsepower in the states, that's one thing that I really don't think you all in the UK understand. Yes, horsepower is a big part of it, but just as big a part is throw you back in your seat torque. Ever see a "real" American muscle car? When it's not in gear and you romp on the gas to rev the engine, there's so much torque that the whole car pitches back and forth.
     
  16. VCS2600

    VCS2600 What's a Dremel?

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    You need the torque of a larger engine to cope with a large, heavy car and also with automatic transmission. Notice how BMW have replaced their 3.5 & 4.4 V8s with 4.0 & 4.8 in the latest 7 series, the previous engines were too small for such a big and heavy automatic car.

    The Chevelle's twin, 1972 GTO 455 HO (7.5 liter)

    [​IMG]
     
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