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1954 Oldsmobile drag race, whole car lifts?


trimacar

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So, latest issue Old Cars Weekly, question about the old days, when a drag raced 54 Olds 88 would, upon acceleration, rise from rear, or all together, rather than typical front end raising (understandable since rear axle was center of rotation).

Why would such an Olds do differently? Is suspension that different?

Inquiring minds want to know!

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I believe 1950 Olds had a coil spring rear suspension with 2 control arms. Torque reaction would make the rear of the car rise on acceleration, along with the normal front rise. In other words the whole car rose on the suspension.

Some leaf spring cars were modified to do this but I don't think any had the right parts from the factory.

1954 Olds, so far as I know, had conventional leaf spring rear suspension.

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So, latest issue Old Cars Weekly, question about the old days, when a drag raced 54 Olds 88 would, upon acceleration, rise from rear, or all together, rather than typical front end raising (understandable since rear axle was center of rotation).

Why would such an Olds do differently? Is suspension that different?

Inquiring minds want to know!

1950 Olds:135 bhp, 303.7 cu. in. Rocket OHV V-8 engine, two-barrel carburetor, Hydra-Matic transmission, independent front suspension with unequal length A-arms, coil springs, and anti-roll bar, live rear axle with coil springs and trailing arms, and four-wheel hydraulic drum brakes. Wheelbase: 122 in.

The rear control arms are very long for this rear coil sprung car.

014-3.jpg

1954 Oldsmobile:The new low-profile bodies demanded a redesigned frame. The basic shape was retained, with nearly straight side-members and a hefty X-bracing plus five lateral cross members. And the rear suspension was reworked. Improved universal joints were adapted along with a new type coil front spring and a new rear spring and shock absorber location. The leaf springs, which had a slight toe-in in the earlier design, were now laid parallel with the wheels, and were moved even closer to the wheels for improved stability.

The two suspensions are different animals, I know a couple of guys that raced those cars (49-50 models) when they were new or nearly new. Their observation was that the coil spring cars lifted straight up ( all four corners ) under hard acceleration. Look how long the lower control arms are in the picture, and notice there are no upper control arms or links as we say, which causes the differential to twist or rotate down.

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Guest buickkuhn

In the multiple race cars that my dad and I have messed with . This is the type of scale we used . for the center of gravity on a car . You can actually make a 15 second 1/4 mile car that yanks the tires off the ground a foot / or you can make a 9 second 1/4 mile car plant the rear and squat just lifting the front to full extension . Learned all the geometry in school and this was one time I had to use it . http://www.how-to-build-hotrods.com/tuning-4-link.html

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Wow, two great articles, thanks. I now have comprehensive understanding....I was never a drag racer so didn't know the math behind the physics behind the acceleration!

Yes, Thank You.

In racing anything, you can have all the horsepower in the world; but if you can't get that horsepower to the track, you can't do anything.

In my previous sentence, I used horsepower; but I prefer to use torque. Now this opens another huge learning curve. Yes horsepower counts; but the torque will pull you through. Check that out; it is very interesting for gear-heads.

Keep the Rubber Side Down,

intimeold

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I've had the HP vs. torque discussion many times with new car salesman, stating their super-door 6 has more HP than my 2001 454 V-8, tow vehicle. Well, maybe on paper, but let's talk torque....which they don't understand.

Best statement I've heard on that subject: you buy horsepower, but you drive torque.....

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I've had the HP vs. torque discussion many times with new car salesman, stating their super-door 6 has more HP than my 2001 454 V-8, tow vehicle. Well, maybe on paper, but let's talk torque....which they don't understand.

Best statement I've heard on that subject: you buy horsepower, but you drive torque.....

I like that quote

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I've had the HP vs. torque discussion many times with new car salesman, stating their super-door 6 has more HP than my 2001 454 V-8, tow vehicle. Well, maybe on paper, but let's talk torque....which they don't understand.

Best statement I've heard on that subject: you buy horsepower, but you drive torque.....

You don't drive torque, but torque is what drives you...or your car

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The old Mopar racers did indeed lift the ass end. The springs were designed to plant the tire which in turn would lift the rear of the car some. Torque was mentioned. TQ is multipled by the convertor, 1st gear ratio, rear axle ratio divided by 2, and then multiplied by the tire diameter. If you look at the tech article posted, the blue 70s Cutlass. Do we think that maybe 400 lb/ft could do that? If we let 400 lbs drop on a 1 foot bar attached to the car, would it lift and twist it like that? No way. Once the TQ reaches the tire (on launch) it's somewhere around 3500 lb/ft. TQ is measured, HP is calculated. It's all just as simple as it is complicated. The Mopar race leafs included a 1/2 leaf in the right rear spring at the front for some applications. The "truck arm" style of rear suspension included long trailing arms that located the axle and pivoted far forward of the normal leaf spring rear designs. Home brewed truck arms can be found under old "gasser" class cars in order to plant the rear tire with as much leverage as possible. Today the same forces can be applied with "arms" as short as 20". It takes 4 aligned to take advantage of an imaginary "instant center" that's above or below and in front of or behind the vehicle's CG. If this gives you the idea that I really like drag racing, well, you'r right. :cool:

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