if i can go 100 mph now at 4 grand and motor is capable of 8 grand, i have a trans that is direct drive with no slippage and my tires are 28 inches tall now could i go 200 mph if i put 56 inch tall tires on it ?
No,because effectivly you are over gearing your engine and would not have enough power dependant on engine to push the gearing .As speed goes up so does drag caused by air passing over/through and around your vehicle.If you over gear this will affect the amount of revs your engine can cope with effectivly restricting your speed therefore the only real way to do this is to get your engine to rev higher with the same size tyres as in Drag cars.Also over gearing will decrease your acceleration.I'm sure others will put thier spin on this thread but it will amount to the same thing although the explaination will probably be more technical.........Mad Marq
yes, for all the same reasons marq stated. he assumed you do not have unlimited horse power and that you do have aerodynamic drag, whereas I believe quite the opposite. you obviously have a very large streamliner with a huge motor. your small wheel diameter is a major hindrence, also the brick under the throttle pedal, fix those two things and you should be able to flat out fly. good luck and write when you reach the foothills. Paul
"yes, for all the same reasons marq stated. he assumed you do not have unlimited horse power and that you do have aerodynamic drag, whereas I believe quite the opposite. you obviously have a very large streamliner with a huge motor. your small wheel diameter is a major hindrence, also the brick under the throttle pedal, fix those two things and you should be able to flat out fly. good luck and write when you reach the foothills. Paul " Bah, HA HA HA .... ROTFLMAO!
Paul, I needed something to jump start my day, its been draging until I read your post. Thanks, at least now if nothing goes right I'll have a smile on my face. Frank
then you need to become a super hero,buy a brightly coloured body stocking wear your underpants on the outside and hey presto! you look a complete twat!.........Lmao Mad Marq
yea i know but if i was to try it without a car i think i need to work out first then go nude covered with rainx.
You need to get that AOL thingy the OCC boys are pushing. Rumor has it, you can go to back in time...
I have AOL and seeing those commercials makes me wonder if it doesn't work better on a vehicle than the internet. Flatrat
[ QUOTE ] if i can go 100 mph now at 4 grand and motor is capable of 8 grand, i have a trans that is direct drive with no slippage and my tires are 28 inches tall now could i go 200 mph if i put 56 inch tall tires on it ? [/ QUOTE ] The way you phrased your question - and disregarding aerodynamic drag - you'd end up at 400 mph at 8 grand with the 56" tires. If you want to go 200, spin the engine up to 8 grand. Assuming the engine has the horsepower, the car has traction and the drag isn't too much - and it probably would be - you'd make it. Even with 28" tires. Drag squares as speed doubles. So here's a question for you. Car with standard trans, one to one ratio in high gear, 30" tires does 50 mph at 2 grand. Does it go 100 mph at 4 grand?
This is a trick question i know and im not going to fall for it. But since you asked i have thought about it and conclude that under normal circumstances you would think you go that fast but i think it depends on the vehicle. drag does play a roll and friction of all the moving parts absorbs some of the horsepower so you would deduce then that you could not double your speed by a ratio increase in rpms. one factor though is that the older the car is and you try to go that fast its possible that as parts fall off that old hulk you loose weight and thereby less weight drag and that could make up for the loss of power from rotational frictions and air drag.all this is speculation as many years ago i lost my speed calculator i think i got from isky or someone so im lost in the actual theorizing of all these aspects. it just seemed to reason that everyone spends all their money on engine parts when a simple thing as bigger tires could be the hot ticket. dazed and confused. i just thought of something if you cut the driveshaft in half and replace the back portion with a tube twice the diameter as the front half would the rear then spin twice as fast as the front portion thereby acting as a overdrive causing the vehicle to go faster ? headache time !
[ QUOTE ] if you cut the driveshaft in half and replace the back portion with a tube twice the diameter as the front half would the rear then spin twice as fast as the front portion [/ QUOTE ] No on driveshaft RPM. Yes on driveshaft SFM. (Surface Feet per Minute.) I forgot to add the 100 mph car above was on a cement highway with no tire or drivetrain slippage. Regardless, the answer is the car would go faster MPH wise because centrifugal force increases the diameter of the tires at speed. You're right that altering rear tire diameters is a good way to bring the final drive ratio right where you want it. If you want to compare tire size changes with diff ratio changes, figure everything as a percentage. IE: a 3.50 diff is about 5% slower RPM-wise than a 3.70 diff. Measure the loaded diameter of the tire to get the percentage change there.
i know your on to something here ! id like to change the subject for a second . bonneville el mirage tires ? for drag racing you go wide for traction, salt and dirt you go narrow for wind resistance and less drag ? at what ratio of speed, horse power, weight ect do you use to determine when your getting too narrow for traction and safety so you don't spin out. do you just try out different tires while watching the tach for fluctuations or is there a formula so you don't waste time testing?
I'm not really the right guy to ask that question of. I was aiming a car at Bonneville and the dry lakes, but it's ending up on the street instead. I have noticed that some cars - in the roadster class - are running wider drive tires than I thought they would. The big problem at the top end venues is traction. Solved by most by simply adding weight. I think there's a balance to be maintained though. The lakes are a bit of a drag race, so weight could be a disadvantage. As a small example, El Mirage has 1.3 miles for accelleration, the traps which are 66' or 132' and .8 mile to get stopped.
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