I know this sounds like a Cafe Society question, but actually is a question about the type of Firebird used in “The Rockford Files”.
Whenever Jim Rockford wants to get his car to go faster, he seems to pull down on his gear shift and send it all the way to the end of the column. However, it looks like an automatic transmission car. You never see him shift gears at any other time.
In every automatic transmission car, I’ve driven , if you pull the gearshift all the way to the bottom, you’re in the lowest gear.
So what was up with the transmission on mid-1970s Firebirds?
Where L1 was first gear and L2 was first and second.
An automatic tranny will automatically (duh) shift from first to second to third. By putting the car in L1, you force the transmission to stay in first gear. Great for getting up to a reasonable speed if you are towing a big weight or whatever.
However, if you manually shift the car from L1 to L2 to D, you select when the car shifts and can therefore get more rpms in a gear. Since cars have more acceleration in certain rpm ranges (more power) you can make the car go faster sooner.
Now, if you were cruising along at 55 mph and suddenly needed a burst of speed, would dropping the tranny into L1 or L2 help you? Imagine driving your stick on the highway and suddenly popping it into second gear. :eek:
As far as I know, that car had the tranny layout we are all familiar with.
Theys must be Hollywood gears.
Maximum power in the old GM tranny = STOMP the accelerator.
Now, maybe…just maybe you could get more rpms by downshifting and holding the shift off until true redline…HOWEVER, more rpms in a GM V8 of the day did not mean more speed. The GM tranny in question shifted just short of it’s redline (400rpms short maybe), but power drops off too much after it’s preset shift point to help.
Could be that he was shifting it as a manual, as Spritle suggests. I once owned a Ford Torino with a 429/C-6 automatic and if I wanted to jump off the line I’d shift manually from 1st to 2d to Drive (3d). The difference in response was marked.
It could be…actually, it is asssumed he is, and if so, it still wouldn’t make alot of sense as:
he was moving along at a good pace already
he moved the shifter down
he was driving a GM product
no gains would come from downshifting manually as the best method would be stomping the accelerator
no gains would come from holding the car in gear longer than the tranny would because acceleration would actually suffer because GM V8’s of that era had power drop off considerably up near the redline.
Fact is, if Rockford downshifted manually, and if that is what he is supposed to be doing with his automatic, then he is not helping the car accelerate anymore than if he just floored it. The most efficient way of making a GM V8 era powered car accelerate is flooring it. If he did downshift, he would have to time his full application of the accelerator just right to at least match the acceleration that would come from just flooring it…and if he floored it and took downshifted just perfectly, he would then have to shift at the optimum point for a GM V8 of that era, and that would be some RPMs fewer than redline.
So, Rockford might have been downshifting his automatic, while pressing the accelerator to the floor, to ultimately move faster, but even if he was doing that, he was actually hurting his total capacity to accelerate.
Also many GMs of that era had “kickdown” cables, which would give that quick lower gear burst, then snap back to the optimal gear. A cool thing to do in High School auto class was to shorten one specific spring found in the GM automatic transmissions so the car would “chirp” (burn rubber) in between each gear. Transmission life was cut in half or more by that, but we sure were cool. I knew guys that would do the shift into low gear to get initial power, but they soon realized that there was no way to match the efficency and timing of the kickdown cable. Maybe James didn’t figure it out.
I checked out that site and maybe I’m wrong, but I think Rockford had an earlier model than '78 in the begining of the series. I’m almost sure he drove one with round headlights for the first few seasons, which would have to be a '76 or earlier.
In fact, I remember a really early episode where his Firebird explodes and that was a goofy-looking '73 model (maybe they just used an old one to blow up).
