thats a great site Derek thanks for the link. As far as the gear ratio calculators go, mine is quite comprehensive and combines many of the others into one. Im always trying to improve it and would be interested in your input. Its here http://ackermana.com/gearhead
an old time carb tuner/racer told me in order to achieve the best mileage one must try to run the engine at the rpm where the vacuum is the greatest. that makes a lot of sense to me.
I know an insurance defense attorney in Miami. He tells me that there is a scam a minute for car crashes in Florida. The most popular one is to cut a car/truck off and slam on the brakes to purposely get hit in the rear. Then sue for the rear end collision. The insurance companies have to spend big bucks to defend these cases , even if they win and don't have to pay off.
The Roadmaster pings on 91 octane 10%ethanol. And anything else with less octane. I found some 87octane non-ethanol and I mix it 5 to 1 with 112octane leaded racing fuel. That gives me about 93 octane. But, because it's not pinging now, I'm opening up the four barrels and driving it like I stole it. The mileage has dropped to about 8mpg . But, I'm having a blast!
what do they sue for? to get their car fixed? for whiplash? or are they hoping for a road side settlement of cash?
All of the above. They weed a lot of them out. But that costs money. And the victim's car still needs fixing
Q: i wonder how many of these scammers get killed when the mark doesnt stop and plows right into them? A: not enough.
Slightly off topic but imagine what a little 63 Skylark would get with a direct injected 215 with overdrive lockup trans. I knew someone with one with a 4 speed that was getting easy 25mpg hwy back in the 70s.....and he wasn't that easy on it.
Aside from a drop in highway RPM's, would my stock '71 GS 350/TH350 benefit from a 200R swap? I don't do any racing, but the car sure is sluggish, especially off the line. What would be a good rear end ratio for this mod, 3.42 or 3.73? Thanks
You probably have a 2 series gear now?, with just changing to one of the mentioned gears would give you much more off the line getup and go. If the plans are still to go with a 200R4 then you want to match it with the 3.42:1 or numerically higher gear so you can shift in O/D at around 45 mph. A numerically lower gear will either shift later than 45 mph or will lug the engine down. GL Derek
There are other more common reasons for a car being sluggish off the line. Have you looked at the tune? What is your current rear gear? A GS350 should have at least a 3.08.
Car runs decent. Springtime project is to convert to HEI (daves small body hei) and employ your 'power tune' method. I currently have the stock points set up timed at ~10*. Pretty sure I presently have 3.08's in there now. It sounds like swapping to an OD trans is a nice way to gain a little torque/power, while still keeping the original matching #'s 350, no? Thanks
Your initial timing tells me nothing. It is more important to know what the total timing is, and to get the mechanical advance all in by 2500 RPM. That will make a huge difference.
Same '72 with 350 and 430 would get about the same. Slight edge to 350. 455 in a '70 squeaked 22mpg driving slow on a roadtrip. There was an issue so I kept it to 50-55 which managed to help avoid overheating. Still ran warm which I think helped economy. Otherwise, I think all my old Buicks (3) would get about 14-15 hwy. Disclaimer: other than 22mpg everything else is subject to memory fade. It has been decades.
Our '72 Cutlass with the THM-350, a 350 4bbl (Quadrajet) 200 hp emission motor, and a 2.73 axle would consistently get 20-21 mpg on the highway at 65 mph. I had to battle with GM to get that axle - we rarely buy a car "off the floor". With piston engines, swept volume must be considered in fuel economy calculations. As a 455 has 1.3 times the swept volume of a 350, it should, all other factors being equal, get about 76% of the fuel economy of the 350. Fortunately, the bigger engine has more torque and can pull a taller gear ratio. I believe that GM offered a 2:63 or something close to that. This would improve fuel economy a little bit.
how much taller gear? more than 1.3 times taller? otherwise it would be no advantage right? that would be a 2.36 to equal a 3.08 with the 350 to offset the greater displacement. no?
I think it would. I have a 70 Stage 1 that went from a turbo 400 to a 200-4R. I had and still have 3.73 rear gear. The 200-4R will give you a lower first gear so you can get up and go faster and give you a higher top gear to get better mileage. Depending on tires, I'd suggest no less than a 3.42 rear end. You could get by with as much as a 4.11 rear end with taller tires. My motor turns about 1000 RPM per 30MPH (2000=61MPH, 3000=92, 6000=185 ) with 3.73 and 275/60-15 radials. Like Larry said, a good tune and curve once you get the HEI conversion should wake it up a fair bit. Also, make sure your choke is fully open when warmed up and that the quad lockout is not stuck. Then, with the motor off, have someone in the car mash the pedal to the floor while you check to see that the carb is also fully opened.
in a stock 70 455 in a wildcat 2.78 rear from Greenbay Wi. to Tennessee at 65 mph i averaged 19.7 mpg of course this was before the ethanol was added to the fuel after the ethanol my mileage dropped to 15 now the new 462 gets 12 on the highway at 75 just saying jake
