G M Turbo 400 owners can now have the advantages of a high-stall converter without suffering the consequences. By Leonard Emanuelson Building a dual-purpose street/strip machine amounts to a bunch of trade- offs. You can't have too much car- buretion or the car will have a giant flat spot. You can't use a real radical cam- shaft because it just won't live. These trade-offs continue right on down to the rear-end gear ratio, which can't be the optimum because the car just wouldn't be practical on the street. That brings us to the subject of torque converters. Ideally, you should use the highest stall-speed torque converter

t'sI almost too good to be true, but there is a torque converter that actually has two different stall speeds-It is called the variable-pitch torque converter and was used b y G M on their 400 Turbo Hydra-matic trans- missions from '65=67 for Buicks, Oldsmobiles and Cadillacs. Now this same available for the best quarter-mile system is available from performance. The higher the stall Kenne-Bell Performance speed, the more radical you can go on Products, the engine components. For street use you want just the opposite, the lowest car a tendency to creep forward. Then now offers both the converter and pacts stall speed converter available for the after the car has moved away from a needed to convert any 400 Turbo for utmost efficiency and lowest heat build- stop, it can be switched to the low stall use with the variable-pitch converter. up. Here we are again at opposite ends speed and reap the benefits of reduced Jim Bell of Kenne-Bell has taken the of the world trying to find the fine line converter slippage. variable-pitch converter a few steps that is the ideal compromise. farther. Actually there are two "VP" We aren't going to try to fool you by Without . getting into the theory of converters, a 13-inch-diameter model telling you there is an ideal compro- how a torue converter works, we will that was standard equipment in the mise, because. a compromise is just attempt to explain how a variable-pitch heavy cars and a smaller 11-inch model that, a compromise. However, there is a converter differs from a fixed stall that was standard equipment behind torque converter for the GM 400 Turbo speed converter. Inside a torque con- the smaller V 8 and V 6 engines. In. Hydra-matic transmission that gives verter there are blades and vanes that stock form the 13-inch converter has a some lattitude in each direction and fits determine the amount of stall speed by high stall speed of 2400 rpm and a low the bill for the average hot street ma- the angle at which they have been pre- stall speed of 1800 rpm. The 11-inch unit chine or street rod that occasionally sees set. The variable-pitch converter, as the has a high stall speed of 2800 rpm and the bracket races. It is a variable stall name implies, can vary the angle of the same low stall of 1800 rpm. The speed converter that has a very low stall these vanes and blades by a hydrauli- Kenne-Bell - VP" converter is available speed of 1800 rpm or, with the flip of the cally operated piston system for two in three different versions. They have switch, a 2600 rpm stall speed. This is different stall speeds. Kenne-Bell increased the stall speed by machining really a near-ideal situation, since an Performance Products_ has capitalized the stator piston (check photo) so the engine with a big cam can idle freely at, on the fact that GM phased out the blades close farther, giving a higher let's say, 1200 rpm without giving the variable-pitch converter in 1968 and stall speed. The modified 13-inch POPULAR HOT RODDING 17 The variable-pitch torque converter is available from Kenne-Bell in two different diameters (13- or 11-inch) and with three different stall speeds.

To convert any GM 400 Turbo Hydra- matic transmission for use with the variable-pitch converter has a high stall of 2600 rpm torque converter and the 11-inch now stalls at 3400 you will need this rp m. pump assembly and The third "VP" converter from drilled shaft along Kenne-Bell is a 13-inch unit modified with this special for RV vehicles or anyone desiring solenoid. Kenne-Bell mproved gas mileage. With this provides complete i instructions and particular converter the switch that also offers complete changes the blade angle is usually transmissions wired into the brake light switch, so already converted whenever the brake pedal is depressed for the "VP''and the converter goes into the high stall modified for high- position, permitting the engine to idle performance use. freely. converter 'is switched to high stall. engine with no hassle. For the real hot street/strip machine, As soon as the car has launched and Take it from us, this is one of the few the Kenne-Bell modified 11-inch "VP" engine rpm is up around 4500 rpm changes available to help make your hot converter is the hot setup. It is the same (almost instantly), then the converter street machine easier to live with on a converter that has been used on all the is switched to the low stall position. day-to-day basis. Jones & Benisck record-holding Buicks It really works great and is worth any- and one of Kenne-Bell's company where from a half-to a full second off the Stage 11 1970 Buicks that ran 10.40s, ET over a stock torque converter! 1 26 mph weighing in at 3600 pounds. Along with the variable-pitch torque With the popularity of the Chevy Turbo Yet the converter will act just like a converter and conversion kit for all 400 400 transmissions making these units stocker on the street. Turbos, Kenne-Bell offers complete scarce in the junkyards, Kenne-Bell Jim took us for a offers this low-cost adapter that will ride in a "VP"-equipped Buick and ex- transmissions already converted and mate any 400 Turbo trans to a Chevy plained the optimum driving technique. modified for high-performance use. engine. His cars are usually set up with the stall Due to the popularity of Chevy Turbo speed changeover switch mounted on 400s, Kenne-Bell also offers an adapter the gear shift lever. For takeoff, the kit that links any GM Turbo to a Chevy

Here is the variable-pitch stator assembly partially dis- assembled. The stator blades (arrow 1) can rotate when acted upon b y the stator piston (arrow 2). The blades are now in the closed (high stall speed) position. When the blades rotate open the stall speed goes to the low 1800 rpm) condition.

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