The snooty died-in-the-tweed-wool sports car set may have looked down on the standard Powerglide in the ’53 Corvette as utterly unsuitable for the track, but maverick Texan Jim Hall had the last laugh ten years later. His groundbreaking series of Chaparral road racing cars bristled with innovations, especially in aerodynamics. The Chaparral 2, which initially had a Colotti Type 376 4-speed, got a two-speed torque converter semi-automatic transaxle in 1964. It is said in numerous sources that it was “Powerglide-derived” or used certain Powerglide parts, almost certainly its torque converter.
“I’ve heard [Jim Hall] say that the big advantage of the automatic transmission is that it lets the Chaparral driver use his free hand to wave at the other drivers as he passes them!”
-Roger Penske, joking about Chaparral’s innovative automatic transmission
Not a lot of details are known about the exact specifics of this transaxle, except that Hall was very much plugged into GM’s skunk works and was the beneficiary of all sorts of goodies despite GM’s self-imposed ban on racing. The 2 had an aluminum 327 thanks to his benefactors, and undoubtedly plenty of help with that transaxle. It was shifted manually, but many references say that it was Powerglide-based and/or used PG parts. Even if it didn’t have a lot of genuine PG parts, the 2’s transaxle showed that a torque converter and two speeds were perfectly suitable for the fastest racing car in the land.
The powerglide came in real handy when he used a moveable wing. The wing was operated by a foot pedal.
I have used an original Chaparral 2 speed ‘auto’ since 2010 in my 2a replica for British hillclimbs . The box is as found and has had no overhaul work. The only standard component is the torque converter for which the stall speed is raised to 3200 rpm . There is a neutral and reverse but all gear engagement when stationery is with the engine off to save the dog clutches. Makes three point turns tedious. I don’t drive competitively but the two professional drivers who do find it makes no difference whether they start in 1st or 2nd. Only essential information is
not to hold it on the brakes for more than fifteen seconds- if it overheats drive disappears. Little appreciated fact : trans weighs 75lbs , Colotti Type 37 weighs about 180 lbs. Car is on Facebook.
Powerglide: the Rodney Dangerfield of transmissions.No respect it gets,even though the millions who drove them loved them. Rebuild a Powerglide? Never seen it once.
Seen it MANY times
I fried the PG in our ’65 Impala wagon with the 300hp 327. Teen abuse, offroad, mountain driving and a little towing. The good news was that the rebuilds were relatively cheap, unlike today’s 6, 8, 10! speed units.
Many drag racers ran Powerglides…sure they were beefed up but there had to be a sound foundation to start with.
Cars with more power than fraction don’t need more low gears. They can just spin the tires to keep the engine in the powerband. That’s why the Chaparral started with just two gears, then added more gears as tires became wider and grippier. The low rotating mass of the Powerglide is a significant advantage in drag racing
I have read that the transmission in the Chapparal (whether or not it was a Powerglide or a derivation from the same) did not have a neutral position. The cars had to be started in low gear with the driver’s foot firmly on the brake pedal. I don’t know this for an absolute fact but I do remember reading about it. I can’t imagine having any kind of transmission without neutral but who knows.
You are very close. They did as a matter of protocol generally start the cars with the transmission gear engaged. However, it did have a neutral “gear” for lack of a better term. Therefore, it was possible to start the cars in neutral. From the book “Chevrolet–Racing? Fourteen Years of Raucous Silence,” there was a dog within the transmission that engaged the gears, and engaging first gear from a neutral start was obviously more harmful to the transmission. It shifted in a manner analogous to a non-synchro transmission in that the driver had to lift slightly while carefully engaging another gear to minimize damage within the transmission. It’s also noted that it was Chevrolet that designed the Chaparral auto, and it was Chevy that maintained them. There’s a comment in the book that the transmissions from the cars driven by Hall invariably showed less wear and damage than those from cars driven by all other drivers.
Yeah, but you know those snobs of ’53 had a point. A Blue Flame at 5,500 revs might give you 68, but not for many drives, and besides, it’s still only 68.
In the real world, there’d be lots of tight corners in real driving( or club racing) where the multiplying effect of the converter is done and the motor is going to bog until speed winds up.
The answer would be to have bugger-all weight and then a racing engine – say, an aluminium V8 – that probably did 7,000 all day and was used mostly on open-sweeper circuit driving. Why, then a 2-speed automatic would be excellent, speed never really below 30, low topping out at 95…
Still, a most entertaining factoid, and the dry Penske comment is a joy.
Wonder if it won anything of note?
“The updated Chaparral 2 (with automatic transmission) won numerous events in the 1964 season of the United States Road Racing Championship (USRRC) including races in Pensacola (the 2’s first-ever victory), Laguna Seca, Watkins Glen and Mid-Ohio. The car continued to dominate race tracks the following year, beating the iconic Ford GT at the 12 Hours of Sebring.”
-www.windingroad.com
Ha! So it was quite the failure, then.
Actually, given that highly impressive record, I wonder why an auto was not then adopted across the board in this class.
Because this auto was designed by Chevrolet R&D. Penske and Hall had near exclusive access to Chevy R&D throughout the 60’s. This transmission was basically a Chevy pet project that started as a one speed, went to two then to three speeds. The tire technology, or lack of, when this first appeared was such that a single speed was sufficient to make full use of whatever traction was available In a light weight, V8 powered car. Gears were added as tire grip improved and power increased. Hall, being Chevy’s R&D partner and involved in this racing class, was the only team that could use this transmission. No other team had the wherewithal, money, engineering talent, time, materials to develop an auto on a timely basis that would withstand the rigors of racing. Hall had all of Chevy’s resources behind him.
39 races for the Chaparral 2 with “automatic” — 22 wins.
Has anyone been to the Chapparal exhibit at the Petroleum Museum in Midland TX?
https://petroleummuseum.org/chaparral-gallery-exhibits/
One of the cars is taken out for a drive every two months.
““I’ve heard [Jim Hall] say that the big advantage of the automatic transmission is that it lets the Chaparral driver use his free hand to wave at the other drivers as he passes them!””
It’s the “…as he passes them!” part that I find most interesting.
Wild Guess: “Powerglide” based, but not the RWD ‘glide. I bet the starting point was the version used in the Corvair, or the Tempest. The ’63 TempesTorque was optional behind the 326 Pontiac engine, and had the heavy-duty Powerglide gearset.
Later RWD Powerglides had the automatic shifting removed, they were sold as “Torque Drive” transmissions in the price-leader cars.