Bnuckols

Looking for some details or tricks needed two pull 2 speed transmission.

joe_padavano

I'm not sure what your question is, exactly. Are you asking about removing the trans? Swapping it? Or what? That two speed is a Super Turbine 300, called a Jetaway by Olds. Contrary to what many people think, it has nothing in common with a Powerglide.

Bnuckols

Sorry left out the most important info tricks for removing transmission and leaving engine in.
found a lot of help on here about going to a th350 no issues. Debating now on the Th350 our dropping more coins on a tremec A41 about 3k more.

joe_padavano

Ah, that makes more sense.

No big deal. Rent a trans jack. Once you get the crossmember out and the bellhousing bolts loose from the block, lower the trans jack. The engine will rock backward but will balance on the motor mounts. Just remove the distributor cap first to avoid breaking it on the firewall. If you get nervous, use a floor jack with a piece of wood under the oil pan sump.

Koda

Is the idea to leave the torque converter on the flexplate?

joe_padavano

Not unless you want an ATF shampoo...

That was not intended to list every nut and bolt necessary to pull the trans, just the tricks.

Bnuckols

That’s a question I haven’t thought about if I go to the Th350.
thoughts anyone?

joe_padavano

You can't leave the converter on the flexplate. You will not get the trans reinstalled. It's difficult enough to get the converter fully seated in the trans when the trans is on the ground. More to the point, your Jetaway has a switch pitch converter. The TH350 does not, so you cannot reuse it in the new trans.

Bnuckols

Thanks getting the help I need!
Would a 1600 to 2000 stall converter be a good fit for the Th350 in this set up ?

joe_padavano

Depends on engine, gears, and how you plan to use the car. Higher stall speed will usually help off the line, but at the expense of increased slippage and heat everywhere else. For a drag strip only car, it's easy to select the right converter. For a car that needs to operate over a wide range of RPMs and load cases on the street, it's more difficult. Personally, I'd err on the side of too low a stall speed than too high.

http://www.tcsproducts.com/media/1/T..._Converter.pdf

http://www.roadrunnerconverters.com/...nsmissions.htm

https://revmaxconverters.com/part-un...-stall-speeds/

Bnuckols

This is great information! not looking to make a drag car this is just a great classic cruiser unless the motor goes then all bets are off. Looking at the specs I don’t need to go over the 2000 mark that’s for sure.
Drive train just needs a little waking up! So between the trans and converter upgrade should make it More responsive and HAPPY 😃

thank you

jcdynamic88

just changing to a th350 will be a HUGE improvement.if the motor is stock i would leave the converter stock.

Bnuckols

Yea pretty much stock bought a kit from Mondello Performance intake manifold new dual pumper carb, and hei distributor, plugs and wires. They said it would ad 70 to 80 hp to the 320? I think the 850 cfm Holley May have been a little to much but it runs after dialing in.

Bnuckols

I’ve heard the bell housing bolts where a bitch to reach?

Fun71

I don't know if this year had a switch pitch converter, but aren't the switch pitch setups something like 1800/2400 RPM?
Anyway, I would not use a 1600 RPM converter; that would be really sluggish off the line. 1800 to 2000 would be my choice.

69CSHC

That sounds extremely optimistic to me... and i'm guessing you have barely felt much if any seat of your pants difference ?

However upgrading to a TH350 is gonna feel like you added 80 HP for sure. We are talking up to a 10 MPH gain in the 1/4 mile, and that is HUGE !

Motor Trend tested a 1967 Cutlass Supreme 320 HP Jetaway and 3.08 gear, It hit 78.5 MPH in the 1/4 mile. 0-60 took 11.22 seconds
Car Life tested a 1969 Malibu Chevelle 300 HP TH350 and 3.36 gear, It hit 87.6 MPH in the 1/4 mile. 0-60 took 7.8 seconds.

If you feel the Chevelle is apples and oranges I offer you my personal stats on my TH350 Stock Supreme with 2.78 gear. 89.59 MPH in the 1/4 and 0-60 in 7.2 seconds.

Your car has 10 more gross HP than my car stock to stock. Your base curb weight is 2 lbs lighter than my car. You have a better gear for performance than I have. (1967 Cutlass Supreme Convertible is 3.08 gear standard) All that means your car should be quicker than my car, and the only reason its not is because the Jetaway strangles your power. Keep in mind My trans is stock no shift kit and stock torque converter which is 1400-1600 stock stall.

Just swapping to a TH350 with my stock converter will be tremendous for you. If you still want more stall I was recommended a Saturday Night Special by TCI, stall is 1800-2000. Via a Summit Racing tech. He will ask you for your current set up, wants, and goals, In my case I go to track from time to time. Even if you don't I believe that converter may suit you well.


http://wildaboutcarsonline.com/membe...omparo_1-4.pdf

http://wildaboutcarsonline.com/membe..._Test_1-12.pdf

https://www.automobile-catalog.com/m...ible/1967.html

jmos4

Hi,

Here is a link to the 65gs site that list a few articles to add a shift kit to a st300, it does firm up the shift but all and all a th350 would be better update

http://65gs.com/board/index.php/topi...qd6miqo0d4uro5

Regards,

OLDSter Ralph

You'll be lucky to get one third that "70 to 80 HP". You might want to do some checking on where you got your stuff.

joe_padavano

"They" would be wrong. A 850 double pumper is waaaaay too much carb for an otherwise stock 330, and the DP is not what you want on a street cruiser. The stock Qjet likely would make more power and would certainly have better driveability on the street. Changing to an HEI does nothing for power vs. a properly maintained points system. Again, any perceived improvement would be due to replacing worn points and deteriorated wires with new parts.

It did. 1967 was the final year for the switch pitch. And yes, you are correct about the two stall speeds, however the 1.76:1 first gear in the Jetaway still pales in comparison to the 2.52:1 first in a TH350.

dukedkt442

Regarding the pulling of the transmission, I'd also add to get the car as high in the air as possible, or you won't be able to get the trans out on the trans jack (as in my case). I had to put a fulcrum on one end to rest some 8' 2x4s, slide under the trans, and then remove said fulcrum to safely lower the trans on the ground by myself. Getting it back into place was the reverse, and not too hard. I was limited with regards to how high I could get the car, so I had to get creative.

Coastie

Can't say anything about swapping, but mine has a th350 in it and I love it.

69CSHC

Hear hear !

I am going on my 6th year of ownership with my 69 I still have the point set that I bought the car with in 2014. It was fully tuned just before I bought it. Since then the plugs have been changed twice as well as the cap, rotor, and condenser. I have looked into changing the point set several times but my mechanic tells me don't bother. He says the points I bought to replace whats in there is garbage comparatively. And the original is still in great working order. We are talking 20,000 miles later.

The car is running better than ever as we speak. Absolutely killer, took it out the other day, from a 5-10 MPH roll give it 3/4 pedal down and the tire starts to SCREAM. 3900 lbs rolling on the street with rear wheels that are almost twice as wide as factory. Not to mention that I am seeing 13.5 MPG city highway combined.

My guess the previous owner purchased the best points money can buy. Gonna have to try to find a matching set, and eventually change them right ? I mean maybe it will run even better with a newer set...

Bnuckols

You guys make this site beautiful thanks for the advice and input. Will let you know how it turns out hopefully will make up my mind on the Th350 versus a 5 speed Tremec and have it done in the next month or so. If anyone has any input to the Tremec I’d appreciate it. Any way either will be my next step to a nice ride!

Fun71

I have posted many times over the years on several Olds boards about my experience with points vs HEI, and it matches your experience.

Back in the 80s while in school I worked at an auto parts store and a full service gas station that had ignition diagnostic equipment. I had high quality points, cap, rotor, coil, and wires and performed tuneups on my car weekly. At some point a friend gave me an Olds HEI distributor, which I set up with quality cap, rotor, coil, and wires. I saw absolutely no difference in performance between the two setups in regards to 0-60 acceleration time, MPG, driveability, etc.

So a well set up HEI distributor will not show any improvement over a well maintained points system.

Bnuckols

Thanks I’ll keep the old one and who knows one day may change it back. Car was a barn find with 33k on it. Sat for 37 years till I pull it out of the barn distributor is in great shape!
in fact I clean the points and set them and the car was running great when I pull it!

thanks for the input

Fun71

That's what I did, just in case the car's "next caretaker" wants to go back to the original factory equipment.