7" Converters?

Transmission to Rear-end

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7" Converters?

Post by la360 » Sun Apr 01, 2007 8:20 am

When is a 7" converter preferred over an 8" unit?
I am building a 346 cube Mopar small block, that should make peak HP around the 9K mark. I was told by a friend who is helping me with the engine that I will be running a 7" converter, but have had others suggest 8" units.

When do 8" units become inefficient or unusable and a 7" unit had to be used?
Kinda new to this level of racing

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Post by Transman » Sun Apr 01, 2007 11:27 pm

7" for sure. Stall speed around 500 over the peak torque point/around 40 HP shy of peak HP. Stator tailored to the torque multiplication/efficiency needed and fin angle to set stall speed once the stator is selected.
Dealer for TCI, JW, BTE, Trans Specialties, Jesel, Impact, etc.

Maximum Race Engines

Post by Maximum Race Engines » Sun Apr 01, 2007 11:57 pm

Basically, with your set up of small inches, low torque, and very high rpm, I would go 7". I look at a few factors when haveing one built, and engine torque and rpm will tell me. The bigger inch, lower rpm, high torque engines tend to blow through smaller diameter converters, as they tend to slip more. Less torque, higher rpm can use the smaller diameter, lighter converter at those rpms without any issues. It is not just all about "stall" rpm or flash rpm.

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Post by Cammer » Tue Apr 03, 2007 9:59 am

You definitely need to consider the vehicle weight, driveline, tires, chassis, suspension, etc., when choosing a converter.

A good relationship and dialogue with your chosen converter manufacturer is critical to converter selection.

Vehicle classification and the manner in which you drive vehicle will have a bearing on converter selection.

IMO, just talking about choosing an 8" converter or a 7" converter, leaves too much out of the equation.

A Lion In Winter

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