Differential 3.9 vs 4.1
08-03-04, 12:18 PM
#27
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ok so which one is it? can I run 17 inch rims with thinner tires and keep the rolling diameter the same and not have the rear end gearing change or what.Because ive looked for aftermarket rims in 16 inch and theres very little available.Now 17 inch rims are a totally different story.I was thinking of either going with some gold gram light pros or some 5zigen fno1r-c's in hyper black 17x9's all around.
08-03-04, 12:44 PM
#28
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A proper plus-sizing will not change the gearing. Selecting a good quality light wheel with a light, grippy tire will not hurt your acceleration measurably. Low rpm/speed throttle response MAY be affected very slightly, that's about it. This is assuming you aren't putting cheap-*** 28 lb wheels on the car.
08-03-04, 02:29 PM
#29
Originally Posted by DamonB
Where exactly did you study your physics???
Well this is something I saw on a TV program (Sportscar Revolution).
They dynoed their project Acura in stock form then upgraded the wheels to a larger diameter. The overall diameter of the wheel & tire combo didn't change compared to stock but the car lost 5hp after they dynoed it again. Also I think the wheels were in fact lighter than the stock ones. I know it doesn't make much since at first but the explanation they gave made since after they explained what had happend. This is the way I visualized their explanation.
Take two egualy sized bicycle wheels(the spoke kind) and strap on weights(lets say 10lbs worth evenly distributed). On one wheel we'll place the weights close to the center of rotation and the other farthur away form the center of rotation. If both tires are rotated the wheel with the weight farthure outward will be slightly harder to get moving as compared to the wheel with more of the weight toward the center. Does that make since to anyone?
Another example: go to a playground and have someone spin you around on a merry-go-round. Place youself in the center and have someone push you around. As you are rotating, move towards to outer section and watch how fast the merry-go-round slows downs. In this situation nothing changed except the position of the weight. I'm pretty sure most of use can relate to this situation.
08-03-04, 02:35 PM
#30
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hmm.t von does have a valid point I guess.well considering the fact that im either stuck with the stock wheels or I can have a wide variety of wheels in 17 inch trim I guess 17's will have to do.I just hate to think that I might lose power because of aftermarket wheels.
08-03-04, 02:45 PM
#31
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5 hp may be noticeable on an RXS, but not an FD. That's assuming it really was a 5 hp loss. The Dynojet is inconsistent as hell, you could easily get a 10 hp difference between runs without changing anything.....
08-03-04, 02:50 PM
#32
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I guess youre right about that.Hmm decisions decisions.
I think my first real costly mod is going to be a auto to 5 speed swap.
After that ill worry about rims and bodykits.
I think my first real costly mod is going to be a auto to 5 speed swap.
After that ill worry about rims and bodykits.
09-09-04, 06:03 PM
#33
Originally Posted by speeddemon7
considering that our cars are governed at what is it 157 miles per hour I doubt anyone will miss the top speed that you cant even use anyways.That is if youre correct about having a top speed of 178 mph with 4.3 gears.
hmmm, i hit over 160 just fine :-)
http://64.158.28.140/MPEG/TwinVision...s_with_dad.mpg
09-11-04, 06:05 PM
#35
true :-)
i should look into different gearing, I still have some rpm left in 5th at the end of the straight at all the big tracks (BIR, RA, MAM, et) and it would be advantageous to shorten it up (right?) for better acceleration.
i should look into different gearing, I still have some rpm left in 5th at the end of the straight at all the big tracks (BIR, RA, MAM, et) and it would be advantageous to shorten it up (right?) for better acceleration.
Last edited by damian; 09-11-04 at 06:07 PM.
