Powerglide transmission performance

[kencombs]

The 53 standard shift car had babbit rods and a plain 235 engine. The 53 powerglide cars had insert rods and a special camshaft that gave it a few more ponies under the hood to make up for the hydraulic slippage of the powerglide at times.

53 standard shift cars still had a 216. The 235 increase helped overcome the hp loss due running the internal pump that provided pressure for band and clutch application as well as torque convert inefficiency/slippage

 

[kencombs]

Might be true, but isn't reflected in any manuals, factory, Motors, or Hollander Interchange and I've never seen a 53 PG without a 60psi pressure guage. I spent the 60s working on cars in my Dad's salvage/shop part time.

Kencombs, My friend who is Chevy guy says not all 53 PG cars had full pressure oiling. Transition year I guess.

 

[kencombs]

I have heard a lot about the "Babbit" Chevy 6 cylinder eCngines in the 50- 60's era when I was growing up. My understanding of a babbit engine rod is that you have the material of the rod and then a tin coating (the babbit) which is what contacts the crankshaft. Is the design without "inserts" like Fords and others had? Was that the beef...when you wore through the tin coating you had a knocker needing new rods where the inserts could be replaced for a fraction of the cost of new rods?

The real beef with Chevy babbit beaters was the lack of pressure lube to rod journals They rely dippers on the rod big end to gather oil from trays in the oil pan or from oil sprayed by tubes/jets facing the dippers. Worked fine at low speeds and loads, but as higher driving speed became normal they were just not adequate. As I mentioned in an earlier post, my first 'good' car was purchased when the owner threw a rod while on a road trip the length of 66hwy. Made it from Chicago to near Tulsa on the 'new' pavement at the 65mph limit and above.

Also, the machining wasn't as precise as later inserts. Each rod cap had to be shimmed to set the oil clearance. At ring job time you could remove shims to restore the clearance as needed.
Relining at rebuild time was and is expensive compared to new inserts.



che

 

[A . M. Aitkins]

I'm not really looking to get the performance of a modern vehicle. But I do want to be able to comfortably keep up with my local speed limits. Most of the roads I drive on are 45-55 mph and the highways run about 65 mph. I usually don't travel much farther than 30mi.

 

[Keith True]

I'm not comfortable pushing that antique car at 65 for that long.Mine were fine at 55,for long 20 or 30 mile stretches,but 65 is a bit much to ask out of it.I would run mine at 65 for a couple miles at a time sometimes,but only to connect up with another road.I have had antique cars since I got my license in 1972,and I know to keep the antique cars on the antique roads,and use the modern roads for the modern cars.I learned long ago to pick the road that fits the car. Those cars are nice cruisers,but still not up to the abilities of a later 50's car.It's like driving a square peg into a round hole,you can do it with a big enough hammer,but things will get destroyed.Lots of good suggestions here on how to spend your money,but nobody asked how much do you want to spend.

 

[olddavid]

If it has the full pressure oiling which I thought all 235s had (may be mistaken) it should do fine. I had experience with 235s in a'59 Carryall and a '61 half ton pickup. I never worried about doing the speed limit. They could handle it.
Edit: My bad. The early 235s weren't full pressure.

 

[A . M. Aitkins]

I'm not comfortable pushing that antique car at 65 for that long.Mine were fine at 55,for long 20 or 30 mile stretches,but 65 is a bit much to ask out of it.I would run mine at 65 for a couple miles at a time sometimes,but only to connect up with another road.I have had antique cars since I got my license in 1972,and I know to keep the antique cars on the antique roads,and use the modern roads for the modern cars.I learned long ago to pick the road that fits the car. Those cars are nice cruisers,but still not up to the abilities of a later 50's car.It's like driving a square peg into a round hole,you can do it with a big enough hammer,but things will get destroyed.Lots of good suggestions here on how to spend your money,but nobody asked how much do you want to spend.

I'm ok with avoiding highways but I want to be able to make 55 mph comfortably. With all of you guys input I feel the 235 and power glide should be adequate for my needs.

Money isn't really an issue but I would prefer to keep the OE engine and transmission.

I spend about 60 percent of my driving time going 45mph and 40 percent going 55mph

 

[Watthour]

As has been mentioned a couple times, the biggest concern is appropriate cooling. An add-on cooler could be needed to keep the trans temperatures reasonable. Going to an oil-cooled version (ST-300/PG300 as they were called) might be better than an old style air-cooled.

How the trans mates to the engine, axle, and vehicle will be addressed by the proper selection of torque converter. A light sedan with a 3.73 axle will need a lot lower stall speed converter to take advantage of all two ranges of the trans. A heavier sedan with 2.56 gears (I've seen them also) will require a higher stall speed to keep the trans from constantly down-shifting, and that extra slip is going to require a lot greater oil cooling capacity.
FWIW, back in the day as I was working my way through school as a weekend mechanic, a place I worked had a contract with USPS for servicing their local carrier delivery cars. USPS had leased about a billion (it seemed) '74 Nova 2-door sedans (no coupes) and they all came with no radio, no AC, a 230 CID six, and air-cooled Powerglide. It was shocking to realize that they were still building 230" inlines since the "standard" 250" six had been out for years. It was also shocking to see that the air-cooled trans was still sold, but in an aluminum case.

 

[kencombs]

I'm ok with avoiding highways but I want to be able to make 55 mph comfortably. With all of you guys input I feel the 235 and power glide should be adequate for my needs.

Money isn't really an issue but I would prefer to keep the OE engine and transmission.

I spend about 60 percent of my driving time going 45mph and 30 percent going 55mph

With that new info, I'll rescind by earlier recommendation. A stock rebuild will be fine for those needs. That's the way most were driven when they were new or just used cars. The issues I mentioned on arise when trying to keep up with today's interstate level traffic or expecting to drag stop light to stop light with newer cars.

 

[Keith True]

Now that you've narrowed down what you want to do with it,I thinl you'll be fine.Tinker it up,put it on the road,and see if you even like driving the car.You might discover you like it,and you might find out you like looking at the car in your barn better than driving it.Doing modifications before you even drove it and gave it a chance is kind of a solution looking for a problem.That problem may not even exist.If you like the way it drives,but it is too doggy for you,then it can get a small V8,better trans,and a different rear end.Modifying a running driving car seems to go easier than tearing into a non running project that you might not even like.I once bought a 55 with a tired 235 and a 3 speed with overdrive.I bought it to put a V8 in with a 4 speed.Eight years later when I sold it I was still driving it with that tired 235.

 

[Texasmark]

The real beef with Chevy babbit beaters was the lack of pressure lube to rod journals They rely dippers on the rod big end to gather oil from trays in the oil pan or from oil sprayed by tubes/jets facing the dippers. Worked fine at low speeds and loads, but as higher driving speed became normal they were just not adequate. As I mentioned in an earlier post, my first 'good' car was purchased when the owner threw a rod while on a road trip the length of 66hwy. Made it from Chicago to near Tulsa on the 'new' pavement at the 65mph limit and above.

Also, the machining wasn't as precise as later inserts. Each rod cap had to be shimmed to set the oil clearance. At ring job time you could remove shims to restore the clearance as needed.
Relining at rebuild time was and is expensive compared to new inserts.



che

Thanks...have been wondering since my teen years.....but it apparently wasn't priority one or I would have researched it earlier.