Hi folks

Did my car come with a low stall or med stall torque converter.

motor 1974 olds 350

trans going into my car
1977 Buick TH350

witch converter ( daily driver. Not a hot rod driver)

thanks

 

Here's to hoping this thread gets a definitive answer.

I've wondered for quite some time as well as searched extensively. Performance of the 79 H/O was significantly improved once exhaust was opened up. Like on par with the original 442. So I would guess medium. Stock they shared performance with the 83/84 Hurst Olds which had a full 1 point numerically higher rear gear ratio, as well as a medium level performance torque converter. The 83/84 also had a more aggressive cam, was rated 10 more hp, had a better first gear ratio, and weighed about the same.

The extra 30 lb ft of torque for the 79s 350 did an absolutely remarkable job if the stall was base...

 

Unless someone has a parts book, or paperwork detailing exactly what was included with the package, who knows?

Id be willing to bet if the engine has factory performance parts, then the converter is different than the “civilian” parts. That doesn’t necessarily mean it’s unique, GM probably used a converter intended for a different application so it would have the characteristics they wanted.

Decades ago the hot setup was to use a Vega converter behind stout engines. Since the Vega was a lightweight, low power car, a converter designed for that application would obviously have much more stall speed than it normally would. Unfortunately, the converters didn’t hold up very well. Which quickly resulted in the performance converter industry.

 

I am also assuming these different year parts will all play nice

1974 olds 350 engine with a 1977 Buick th350
will I need to change anything to make this work.

 

Have not been able to locate specific stall speed as of yet. But the torque multiplication factor for the 79 H/O is more aggressive...

1979 305 Calais = 2.1
1979 350 H/O__= 2.25

1984 307 H/O__= 2.2

And below for the high compression 350s.

1969 350 Supreme = 2.2
1969 350 W31____ = 2.3

Thank you to the Automobile Catalog.

For those unfamiliar, the 2.3 times factor for the W31 means that torque is multiplied 2.3 times at stall.

So yes the 1979 H/Os torque converter is in the performance realm for Olds. And its factory performance backs it up. (Just for good measure the 1968 H/O = 2.3) However when power was down and weight went up (early malaise) Olds did their best to offset the negatives. Torque multiplication on the 4000 lb 1974 180 hp 350 CID Supreme was 2.5 (even though it had the same torque rating as the 79 H/O at 275 lb ft) But the 79 H/O is 550 lbs lighter. And now we know why the 79 H/O is as quick as any RWD Olds ever was after 1974, stock to stock.

P.S. the top of the line 1977 Regal Coupe came with an Olds 350 CID with same power ratings as a 1979 H/Os 350, a TH350 and the same 2.25 torque multiplication from its converter as your car originally did. But weighed 400 lbs more than your car.

 

I'll be finding all this out at Beech Bend when I put my bone stock 79 H/O on the qtr mile in the Fun Rockets class. I won't be doing a thing special to it, I'll just drive it there, run it, and drive it back. And NO burnouts. Can't wait to use the right side of that Dual Gate Shifter!

 

Starting from scratch
opened the transmission and there was a
hole I could put two fingers in.

looking for a good TH 350 folks

 

Normal. That’s an area that didn’t need any material, so HydraMatic didn’t set up the die to cast aluminum there.

If you think about it, all the lube oil that’s flung off the planetary gearsets has to have a way to drain back into the pan. That hole saves a little money in material cost, and is a convenient drain. Almost like the engineers knew what they were doing!!

 

I do hate the look of casting holes, though.

 

There was quite a bit of metal flakes in the pan not sure if I should take the gamble. That hole is ragged and ruff and next to the shifter

quess I need more convincing to move forward with this one.

 

Some metal flake is normal for a used transmission...

The hole is normal as both Matt and Koda attest to and is unsightly at the same time.

Here is a Reddit question and answer on same subject with pic. https://www.reddit.com/r/MechanicAdv...upposed_to_be/

Also with regards to your original question. Here below is a high performance converter chart. Stating both stall and multiplication factor.

Bottom three are stock/equivalent. And you can see how as stall increases so those multiplication. Apples and oranges but you can see how they go hand in hand in all out performance.

Love it ! Looking forward to your results. Please open a dedicated thread and post all pertinent info. So I can live vicariously through your experience.

If she does end up spinning off the line, no controlled burnout. But maybe a punch peel from the glue to just before the lights ? Has worked very well for me ...