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Torque converter

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Hello Americans!. I have a 1970 C10 with a 350 and 700R transmission. How much does a torque converter plays a role on acceleration from stop light to stop light? Don't know my gear ratio but thinking that the right converter may help by not spending a bunch of money on rear end work.
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· Rod...from a Chrysler?
10,182 Posts
Start by checking your gear ratio. Lots of YouTube for that.
What are you engine specs?
If it's real lumpy with power coming on at higher RPM's, a higher stall can help get that breadbox moving.

BTW, it will cost about the same to do the rear end work, as the cost of a GOOD convertor, so I would start there. Only after checking your gear ratio that is. (easy to do, only need to jack it up)

· Registered
1,855 Posts
Since you have a 4 speed automatic with a nice overdrive, I would suggest going with a 3.90 or 4.10 gear ratio first. That is if you have a 28 inch tall tire or shorter.
What size rear tire are you running?

A gear ratio change will really wake this up unless you already have a decent setup. But if you have a highway gear, and want any type of performance in the future, you should start out back first. Because whatever you do for power will always be bogged down if you have a highway gear out back.

Highway gear is a compromise people have to make when they have no overdrive in trans.

· Registered
16,303 Posts
The answer is in there places.

1. What are the cam specs?

2. What is the compression ratio?

3. What is final gearing? This includes the calculated integration of gear ratio and tire diameter.

At issue is the more radical the cam the torque and power curves both pivot about a point and change in amount. Generally the peaks move up the rpm range increasing as they go but reducing under the peak. Increasing the converter stall speed is done to chase this power to RPM movement But is mostly a drag racing thing where the loose converter allows the engine to rev into its upper RPM band while the vehicle is braked at a standstill while staging. On the street this also reduces the pull of high idle speeds these type cams need when at stops.

Increasing the compression ratio as the cam gets bigger helps restore the reduced bottom end torque.

Increasing the overall final gearing is also use to chase the RPM’s where the engine torque and power have gone to.

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