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Discussion Starter #1
I just had shorter gears put into the rear end of my 63, and I had been noticing a high pitched whine at slow speeds and during deceleration. I wanted to blame the rear end but the sound was coming from too far forward in the driveline. Anyway, today I am driving down the PCH and its like my car went into neutral. No gear selection will move it, but it holds park, so I have ruled out the linkage. Being as I have a TH350, I don't suspect the pump either due to how it operates, and yes the fluid is good and full. My guess was either the output shaft or the impeller of the torque converter. After speaking with a shop, I am leaning toward the converter. The tranny is coming out today, and assuming the converter went, what steps should I take toward performance.

Here are some things to consider:
-not a daily driver.
-newer 350 crate engine (unsure of cam profile. Getting new top end soon though)
-TH350 trans.
-3.73 gears
-old converter was 2200 stall I think...
-I enjoy performance!!!


Anyone have any suggestions?
 

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I run 2800 stall area on my turbo 350. And with the 3:70 gears on the back it runs pretty nice. The gears keep it just off the converter when just cruising so im not constantly slipping but when I want to drive it hard it works well.


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Discussion Starter #6
Anyone else with any input? I'd love to get the most out of this purchase
 

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You say you are getting a new top end soon. I would say research exactly what you want then match the convertor to it. If the cam card says the power curve is 3000 to 6000 then a 3000 stall is the way to go. Remember a 3000 stall is what it will flash to under full throttle/load. You should still have good low rpm drive ability. And one good thing is your rpm will not drop down from park to gear.
 

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Discussion Starter #8
You say you are getting a new top end soon. I would say research exactly what you want then match the convertor to it. If the cam card says the power curve is 3000 to 6000 then a 3000 stall is the way to go. Remember a 3000 stall is what it will flash to under full throttle/load. You should still have good low rpm drive ability. And one good thing is your rpm will not drop down from park to gear.
You mentioned rpm dropping in park to gear. What causes that? In park, my car idles at 900 or so and in drive it isles near 700. I never even thought twice about it until this moment
 

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that's the stall of the converter. some cars with wilder cams need to idle higher to stay running. the stall of the converter allows a higher rpm of a slip. if you're idling in park & drive OK with the old converter and don't plan on major engine changes the stall is sounding OK as it is...

if they are building you a converter, talk to them about your complete package and they can tailor it for you... it's not necessary really to have a higher stall than required... it's not a dedicated race car, right?
 

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I just had shorter gears put into the rear end of my 63, and I had been noticing a high pitched whine at slow speeds and during deceleration. I wanted to blame the rear end but the sound was coming from too far forward in the driveline. Anyway, today I am driving down the PCH and its like my car went into neutral. No gear selection will move it, but it holds park, so I have ruled out the linkage. Being as I have a TH350, I don't suspect the pump either due to how it operates, and yes the fluid is good and full. My guess was either the output shaft or the impeller of the torque converter. After speaking with a shop, I am leaning toward the converter. The tranny is coming out today, and assuming the converter went, what steps should I take toward performance.

Here are some things to consider:
-not a daily driver.
-newer 350 crate engine (unsure of cam profile. Getting new top end soon though)
-TH350 trans.
-3.73 gears
-old converter was 2200 stall I think...
-I enjoy performance!!!


Anyone have any suggestions?
your stall should match your cam , compression ratio,rear gear, tranny ,rear tire size and weight of your car if you are getting a new top end I would consider that with a new converter. Look up some converter companies and they will have a form to fill out with info on your car to match the converter complete package
 

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Discussion Starter #11
that's the stall of the converter. some cars with wilder cams need to idle higher to stay running. the stall of the converter allows a higher rpm of a slip. if you're idling in park & drive OK with the old converter and don't plan on major engine changes the stall is sounding OK as it is...

if they are building you a converter, talk to them about your complete package and they can tailor it for you... it's not necessary really to have a higher stall than required... it's not a dedicated race car, right?
The car isn't a daily driver and will be used more for racing events in the future. I'm just confused about getting the converter suited for what the car is now or what it will be in the months to come.

This broken part has thrown a wrench into my planning.

For instance I have 76cc heads now with an 8.5:1 compression ratio but I'm two months I'll have 64cc heads and a 9.5:1 ratio. The gears will remain 3.73. The car will remain the usual weight, and the tires will stay 26" The cam is still being worked out but I could adjust my planning to accommodate a more performance oriented converter.
 

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Discussion Starter #12
It turns out, more damage was done than I had originally thought. The owner before me built the transmission all wrong. A C20 lockup converter from a post 81 car was in the transmission. This had apparently made contact with the pump due to its larger size and position. The whine I was hearing was the pump failing. In the aftermath of all of this burnt up my clutch packs which brings me to this current position.

I put in an order for a rebuilt TH350 with a stage 1 shift kit. ($399 with a two year/unlimited mile warranty). I also will be going with a 2400 stall converter from West Coast Converters here in Southern Cal. That was another $350. All in all, I would have liked to keep that money in my account for a litttle longer, but now I can have some piece of mind.

Let's hope that this will be the end of my driveline woes.
 
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