And he passed away at 97 years old on March 4, 2025, he was still working in his shop at age 95+, the man is a legend!!..
A search says a team of 10 people worked on the car.
My 66 Fleetwood could. That ■■■■ thing wouldn’t fit in my garage.
Wasn’t that GTO a Prfodified 421 supplier to Car and Driver by Royal Pontiac as a stock 389"
Yes, that is why owners of those old GTOs could never match the acceleration times that appeared in the magazine.
I was just wondering what a strong 8 speed transmission would do for a good muscle car
Keep the engine in it’s “power band” range much better… The RPMS would be much tighter between gear changes…
I would love to put an 8 speed auto behind my fun car engine, over it’s 3 speed auto…
Example for Mopars:
"Here is where the engineers let it all hang out with a total of eight speeds forward. This ZF-designed transmission built by Chrysler takes the multi-speed gearbox up to the next level. The advantage of adding ratios between low gear and the final overdrive is to reduce the rpm drop between ratios. With more forward speeds, engine rpm remains within a narrow optimized power range for maximum acceleration. The definition of an engine’s power band is that rpm spread between peak torque and peak horsepower. As an example, the 2021 Dodge Chaarger SRT Hellcat Widebody Redeye is rated at 707 lb-ft of torque at 4,500 rpm and 797 horsepower at 6,300 rpm. This means the power band is between 4,500 and 6,300 rpm for an excellent 1,800 rpm spread. Often this power band is much narrower at 1,400 to 1,500 rpm.
Let’s take a look at just one example of rpm drop from 6,300 at the top of Second gear and its shift into Third gear with the 8LHP90 transmission. This represents a 32.9 percent ratio drop from 3.14:1 to 2.10:1. This means that the engine rpm will theoretically drop from 6,300 to 4,227 rpm which is just slightly below peak torque. This is one small reason why this car is so quick because the engine does not have to struggle with a huge rpm drop below peak torque.
As a comparison, an A727 will drop 43 percent from First to Second – a 2,800-rpm drop. This will push the rpm well below peak torque (as low as 3,500 – not taking into account converter slippage) and the engine will struggle (and take more time) to grunt back up into the power band that starts at 4,500 rpm.
The net gain here is the eight-speed narrows that engine speed drop at each shift. Just the addition of these gears will improve e.t. by perhaps as much as two tenths of a second versus a typical three-speed automatic. Plus, the 8HP70 /8HP90 include a pair of overdrive 0.84:1 and 0.67:1 ratios. The rear axle in these cars is 3.07:1 but when the transmission shifts into 8th gear, that effectively drops the final drive ratio down to an astounding 2.05:1 which puts cruise rpm on the highway at 70 mph just under 1,700 rpm. Yet the overall first gear ratio of this Hellcat combination is more aggressive than a 727 trans with a 5.13:1 rear gear! That’s one reason why these big heavy Mopars can launch so hard. They are applying serious leverage to the launch."
My transmission is a A999 (based on the A904) with 1st gear 2.45:1 ratio, 2nd gear 1.45:1, 3rd 1.00:1… If/when I build my next trans for my fun car, I might go with a newer low gear set and run 1st gear 2.74:1, 2nd gear 1.54:1, 3rd 1.00:1 gear…
By comparison the (basic) ZF8HP70 trans runs: 1st 4.69, 2nd 3.13, 3rd 2.10, 4th 1.66, 5th 1.28, 6th 1.00, 7thand 8th are both OD…
The stronger 8HP90/95 trans runs 1st 4.71, 2nd 3.14, 3rd 2.10, 4th 1.67, 5th 1.29, 6th 1.00, 7th and 8th are both OD…
So with the HP90/95 1st gear 4.71:1 and my 3.91:1 rear gear that yields an 8.62:1 effective 1st gear ratio, but with my current 1st gear 2.45:1 and rear 3.91:1, I am only getting a 6.36:1 effective gear ratio, that is like dropping from a 4.88:1 to a 2.62:1 rear gear ratio, that is huge!!!
Ratios should be correct (mostly) but all these numbers are making my head hurt… lol
Thanks. I didn’t know the history and am glad too. I assumed he hired competent professionals anyway, making it a flippant comment.
The older cars, made before people figured out how to make them weigh less, which made them more efficient and handle better, often in response to increasing fuel prices.
And then they made them heavier again… Current cars are 6% heavier than they were in 1975.
I’ve posted this before. My wifes 2007 Lexus (3.0l V6) was heavier, larger then my 1972 Chevy Vega.(2.3l I4). But the Lexus had better handling, faster, far more reliable, and significantly better gas mileage then the Vega.
Thanks. I didn’t know this. I didn’t read the article. Are they comparing identical categories? I understand people are buying larger cars now.
They aren’t comparable cars, are they? Bigger engine, more room for passengers and cargo.
That’s the point isn’t it? The 07 Lexus being a much bigger vehicle is getting significantly better gas mileage than the Vega. What about that don’t you understand. The Lexus was easily getting 33mpg, Other vehicles of the same era that was the same size as the Lexus you’d be lucky to get 15mpg and no where near the performance and luxury as the Lexus.