Bangshift guys willing to teach newbies???

[Markymark]

Would you guys be willing to answer basic questions from newbies! I love the sport but don't know much about cars or racecars or how they work. My first question is about gears. 4.30 gears, what does the number mean??

[Markymark]

Question number two...what is a power glide?

[yellomalibu]

How to explain... we'll start with the easy one. A Power Glide is a 2 speed automatic transmission GM used for a while. That's it, just low gear and high gear. (yeah, it had Park, neutral, and reverse, too) The high gear is 1:1 ratio, meaning when the engine is turning 2000 rpms, so is the drive shaft that comes out the end of the transmission. (almost?) All transmissions that don't have "overdrive" have a 1:1 ratio high gear.

4.30 gear, actually means the the gear ratio in the rear end is 4.30:1 ratio. The drive shaft will rotate 4.30 times to get the tires to rotate 1 time.
Having a "lower gear ratio" (numerically higher) helps a vehicle accelerate faster. Having a "high gear ratio" (numerically lower) like a 2.73 lowers the cruise rpm, which typically helps gas mileage.
So if the car is being built as a street/strip car, there's a trade off or a sacrifice one must make between performance and fuel mileage - and one must decide which is more important.

[Monk]

Good post......great answer.

[DanStokes]

To answer your first question - that's a lot of what we do here. Folks run into something they haven't seen before and ask others if they have input and usually someone does and the ideas start flying. NO ONE has all the answers (at least, all the CORRECT answers) and we all learn from each other. We were all rookies at one time.

My wife is a violin teacher and a darn good one. She reminds her students that no one is born knowing this stuff. We all learn and the wise among us (like most of the folks on this forum) pass it along. Hopefully, when I'm dead and gone my little tidbits of info will make someone else's life a little easier.

Ask Away!

On the Powerglide question - Yellowmalibu's answer was spot-on but we could carry it a bit further. Powerglides are very strong and can be made bulletproof with aftermarket parts. As drag racing has matured it has been learned that two gears are generally enough (depends on the complete package) - low gear to get the car rolling and high (the 1:1 ratio) to get the car thru the traps. Strip performance is hurt when power is not being applied during shifting however fast the shift so fewer shifts = better drag strip performance. With the toughness possible with a Powerglide it has become one of the primary choices for this type of performance application.

Dan

[milner351]

The only stupid questions are those that remain un-asked.

[Markymark]

Very awesome, I appreciate the explanation. Makes sense!

[Barry Donovan]

To further the powerglide, it has a great purpose.
an aircooled vw broke a world record in a dragster chassis with one.. a very long time ago.

short stroke/self balance/turbined (boosted) little engines are right in heaven with them. A rebuilder can dial those into any curve.

the most recent use I saw with an amazing outcome for modern day is a subaru ej series in a brat.

going real heavy with them was odd back then when they were new, and still an odd thing to do today.

its kinda like a 250cfm monojet carb on 4.1 liters...it will never make sense, as factory built it, but can find a happier place in lighter weight, less cfm.

[Scott Liggett]

The powerglide transmission was chevrolet's first automatic transmission that came out in 1954. It's case was originally was made of cast iron then switched to aluminum sometime in the mid '60's. Its gear ratios are 1.76:1, 1:1. The TH350 three speed automatic that became available in 1967 had 2.76:1, 1.76:1. 1:1 ratios.

While its true many drag racers use the powerglide trans. Those race transmissions dont use any of the factory parts that GM made. In the high horsepower cars use an aftermarket outer case too. The factory versions werent designed for high horsepower. Its why GM never put one behind a big block V8.

[AFFORDILLAC]

The combination of all your guyz posts really rounded that one out...jus like DS said.

[squirrel]

The powerglide transmission was chevrolet's first automatic transmission that came out in 1954. It's case was originally was made of cast iron then switched to aluminum sometime in the mid '60's. Its gear ratios are 1.76:1, 1:1. The TH350 three speed automatic that became available in 1967

Close

PG started in 1950 model Chevys, the aluminum version was introduced with the larger engines and in the Chevy II in 1962, although the 235 and 283 still used the cast iron version that year only. The TH350 came along in 1969 models, the TH400 was first used in Chevys in 1965.

And then there was the hugely unsuccessful Turboglide introduced in 1957 and last used in 61. It had an aluminum case.

[TheSilverBuick]

Good answers to your specific questions. I highly recommend picking up a factory service manual to what ever car the power glide and 4.30 gears are in and read the thing cover to cover. It'll tell you a lot about various systems of a car and the troubleshooting sections will tell you what happens when various things are out of wack. They usually cover multiple engines and transmissions as well as have good pictures and diagrams too.

[DanStokes]

I had forgotten about the Turboglide. That WAS a looser, wasn't it!

The Dynaflow was Buick's automatic for many years. It was VERY smooth and operated with variable vanes - sort or precursor to the modern CVT transmissions. It was VERY smooth which was a Buick requirement but not a great performance trans nor would it stay in one piece behind a lot of power. Went away in 1964, IIRC.

One more common auto trans you may hear guys talk about - the Chrysler/MOPAR A727. Tough as nails but like all things mechanical had it's gremlins, too. Started with a cast iron case and later went aluminum. There was also a smaller Chrysler A904 and again a pretty good piece but designed for lower torque engines.

I'll let the Ford guys talk about the C6 and C4 Ford autos.

Dan

[BangShiftChad]

Markymark,

Welcome to BangShift. We have, without question, THE BEST CAR GUYS ON THE INTERNET. As one of the two owners of this joint I can tell you that we know all these guys and there are no questions we won't answer. In fact, if you have a giant list of questions feel free to pile them on or start a new thread for particular subject matter. Like engine questions, transmission questions, suspension questions, etc.

We are all more than happy to help, anytime. Do you have a car you are working on yet? Or just learning something about the hobby before you buy one?

Let us know.

[Bob Holmes]

I'm 52 and I'm still learning. These guys surprise me everyday.