Pontiac GTO 1970-71
The 1970 GTO was not available with hidden head lights they were replaced by four round head lamps outside of the grill although the car still retained the protruding hood ridge as well as the Endura (low impact speed – no damage) cover around the bumper, head lights, and grill. The GTO was made more stable with the addition of a rear sway bar which complemented the heavier front sway bar to reduce the lean and the under steer. A handling option made available in 1970 was “variable ratio steering” which reduced the turning radius by about 8% from lock-to-lock.
In 1970 the GTO economy engine was deleted, while the basic engine remained the same, while the Ram Air III and Ram Air IV power option were both sold but the latter was a special order. The new power option available was Pontiac’s 455 HO long stroke slightly different from the one offered in 1971-72 model years. This new engine was about the same power as the Ram series but it was less difficult to keep running smoothly at low speeds and it did not have the ropy idle associated with the Rams. A rare option made available in 1970, for a short time only, was “Vacuum Operated Exhaust” (VOE) activated with an under dash lever marked “exhaust” which reduced back pressure when accelerating; the result was the engine had a little more power but a lot more noise. The only engine with this option is the “YS” 400 CID 350 hp equipped with a four speed manual or the turbo-hydra-matic transmission; very rare with 233 units leaving the assembly room so equipped. Skyrocketing insurance rates applied to muscle cars in 1970 contributed to the downward spiral of sales but GTO was still the third bestselling car in its class.
In 1971 the GTO had a few changes in front; the head lamps were closer together, horizontal bumper bars added, with the duel hood scoops moved further forward towards the restyled wire mesh grill. This year the Ram engine series was not available. The basic option was the 400 CID V8 but with lower compression and lower horse power than previous years. The 400 engine is rated at a modest 300 hp (220 kW) at 4,800 rpm. All the engines had a more conservative compression ratio as G.M. was gearing up for the non-leaded fuels soon to come on line. The second engine available is the 455 CID V 8 with a four barrel carburetor which developed 325 hp (242 kW) at 4,400 rpm and was only available with the Turbo-Hydra-matic TH-400 transmission. The power engine option is the new 455 HO V 8 with a four barrel rated at 335 hp (250 kW) at 4,800 rpm. The standard rear end is an open ten bolt with posi-trac available as an option on the 400 engine but the 455 engine could have been ordered with a 12 bolt rear end with posi-trac as a second option. The 455 with a four speed could do 0-60 in 6.1 seconds and the quarter mile in 13.4 seconds reaching 102 mph (164 km/h). “The Judge” GTO was retired in February 1971.