What is it that makes it so hard to get big hp numbers?
08-01-2008, 01:31 PM
#26
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The renesis doesn't produce amazing torque at the crank, no, but it's torque curve is incredibly flat compared to most piston engines, and it revs higher as well. It's not quite the "electric motor" delivery Mazda makes it out to be, but it's damn good for an internal combustion engine. A 300 HP renesis (barring laggy turbo setups) will have more area under the torque curve than any other engine that produces a similar peak HP number. Then you just use proper gear ratios in your trans/diff to put the torque to the ground that you desire.
Peak HP is just a theoretical measure of the top speed of a given vehicle... it doesn't tell you how fast that car will get to that speed. It's pretty meaningless by itself... area under the torque curve (or HP curve if you prefer) is what matters.
Peak HP is just a theoretical measure of the top speed of a given vehicle... it doesn't tell you how fast that car will get to that speed. It's pretty meaningless by itself... area under the torque curve (or HP curve if you prefer) is what matters.
08-01-2008, 02:14 PM
#27
Well, once you're moving, the only real part of the torque curve that matters on an rx8 is above 6k. The redline on the MT is high enough that you never need to drive below 6k. I mean, it's nice in some turbo cars to just drop your foot in top gear and have a nice amount of acceleration, but it isn't entirely necessary. An evo isn't going to go to a track day and just do laps in 5th. Torque curve shapes are important in different ways depending on what you do. A track car wants high torque through whatever rpm band is in use. A drag car wants as much torque following the shift as it can get. Acceleration early in a gear is faster than acceleration later. You could make a case that by tuning a drag car for minimal HP (delining torque curve) is faster than maximum hp (increasing torque curve).
Then again, more torque at all RPMs is pretty sweet too.
Then again, more torque at all RPMs is pretty sweet too.
08-01-2008, 02:35 PM
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Well, once you're moving, the only real part of the torque curve that matters on an rx8 is above 6k. The redline on the MT is high enough that you never need to drive below 6k. I mean, it's nice in some turbo cars to just drop your foot in top gear and have a nice amount of acceleration, but it isn't entirely necessary. An evo isn't going to go to a track day and just do laps in 5th. Torque curve shapes are important in different ways depending on what you do. A track car wants high torque through whatever rpm band is in use. A drag car wants as much torque following the shift as it can get. Acceleration early in a gear is faster than acceleration later. You could make a case that by tuning a drag car for minimal HP (delining torque curve) is faster than maximum hp (increasing torque curve).
Then again, more torque at all RPMs is pretty sweet too.
Then again, more torque at all RPMs is pretty sweet too.
Do enough driving at fast tracks like Road America and you'll gladly give up power from 3-5.5 K in exchange for more headroom from 5.5K+.
08-01-2008, 03:18 PM
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08-01-2008, 04:59 PM
#33
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RE: MazdaManiac, I think I see what you mean showing the dyno, the high end of the hp/torque might be higher on the purple car, but the yellow car has a much flatter torque curve?
08-01-2008, 05:52 PM
#37
When you swinging out east, MM?
08-01-2008, 07:27 PM
#40
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Good info. So what is the desirable torque curve to have the best acceleration from 0-100 mph? How would you calculate getting the correct gear ratios to achieve the best torque to the ground for that?
08-01-2008, 07:29 PM
#41
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No, I don't.
Saying you have "X" amount of power is meaningless. It isn't another level, its just nut-swinging.
If you have two cars - exactly the same in every way and both making 300 ft/lbs of torque - but one makes 500 HP and a torque curve shaped like "^" and the other makes 300 HP, but has a torque curve shaped like "¯", which is the faster car?
I will take a car with half the power but twice the area under the torque curve any day of the week in any form of racing - even bracket drag racing.
Saying you have "X" amount of power is meaningless. It isn't another level, its just nut-swinging.
If you have two cars - exactly the same in every way and both making 300 ft/lbs of torque - but one makes 500 HP and a torque curve shaped like "^" and the other makes 300 HP, but has a torque curve shaped like "¯", which is the faster car?
I will take a car with half the power but twice the area under the torque curve any day of the week in any form of racing - even bracket drag racing.
Also in the long run the car with a the torque curve shaped like "¯" will with out a dought win but if its just a 1/4 mile i'll take the car with the torque curved shaped like "^", it's just a 1/4 mile most drag cars only go up to 4gear. thats just how i look at it....
Last edited by Rotore_787; 08-01-2008 at 07:36 PM.
08-01-2008, 08:08 PM
#42
Exactly Rotore, it's not just the raw power, its that I would really like to invest some time and money into my car and make it something special, but I see a lot of modded Rx8s that don't seem to get a lot of notice or attention in the tuner scene because they have low hp numbers. I mean, I don't give a rats *** what people think if I like it, but I do like torque/hp and was curious what was keeping 8s from showing higher numbers.
I would love to have a 20B swap because I think the 3 rotor engine is the best sounding engine I've ever heard... I mean, it sounds like it's trying to eat someone. *drool* That being said, I don't think that a 20B swap is doable for me atm just due to price of the swap. I would never go LSx with an Rx8 anyway, because I've had a Corvette and although it's a great engine it loses the characteristics of what an Rx8 is about to me.
I would love to have a 20B swap because I think the 3 rotor engine is the best sounding engine I've ever heard... I mean, it sounds like it's trying to eat someone. *drool* That being said, I don't think that a 20B swap is doable for me atm just due to price of the swap. I would never go LSx with an Rx8 anyway, because I've had a Corvette and although it's a great engine it loses the characteristics of what an Rx8 is about to me.
Even in an N/A 8, just keep the revs high and it will put a smile on your face every time. Especially when getting it sideways around turns...
I agree with everyone on the HP doesn't mean anything, its about the torque and the curve it produces. Alot of people I work with ask me how much HP I will get after I get the MM/BHR turbo kit. I tell them I'm looking for about 300 at the wheels and they seem disappointed. I try to explain the torque curve to them but they don't get it. People get so stuck in HP numbers and they think that's the only thing that matters. Very annoying. If they drove the car with the kind of numbers MM was putting down, I'm sure they would change their minds. That's fine though, I will have fun in my car and the ignorant people can just go buy their muscle cars and can be unhappy.
At least they will have 298342946198247useless RWHP that can only go in a straight line along with the useless "bragging rights" to go along with it. Boo. --Jonathan
08-01-2008, 08:24 PM
#43
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RX-8's don't get a lot of attention in the "tuner scene" because most people are ignorant and don't know squat about them. They hear rumors about different things like reliability, eats oil, low end power and automatically assume they suck when they don't know any facts about it.
Even in an N/A 8, just keep the revs high and it will put a smile on your face every time. Especially when getting it sideways around turns...
I agree with everyone on the HP doesn't mean anything, its about the torque and the curve it produces. Alot of people I work with ask me how much HP I will get after I get the MM/BHR turbo kit. I tell them I'm looking for about 300 at the wheels and they seem disappointed. I try to explain the torque curve to them but they don't get it. People get so stuck in HP numbers and they think that's the only thing that matters. Very annoying. If they drove the car with the kind of numbers MM was putting down, I'm sure they would change their minds. That's fine though, I will have fun in my car and the ignorant people can just go buy their muscle cars and can be unhappy. At least they will have 298342946198247useless RWHP that can only go in a straight line along with the useless "bragging rights" to go along with it. Boo.
--Jonathan
Even in an N/A 8, just keep the revs high and it will put a smile on your face every time. Especially when getting it sideways around turns...
I agree with everyone on the HP doesn't mean anything, its about the torque and the curve it produces. Alot of people I work with ask me how much HP I will get after I get the MM/BHR turbo kit. I tell them I'm looking for about 300 at the wheels and they seem disappointed. I try to explain the torque curve to them but they don't get it. People get so stuck in HP numbers and they think that's the only thing that matters. Very annoying. If they drove the car with the kind of numbers MM was putting down, I'm sure they would change their minds. That's fine though, I will have fun in my car and the ignorant people can just go buy their muscle cars and can be unhappy.
At least they will have 298342946198247useless RWHP that can only go in a straight line along with the useless "bragging rights" to go along with it. Boo. --Jonathan
08-01-2008, 08:28 PM
#45
08-01-2008, 08:37 PM
#46
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08-01-2008, 09:40 PM
#49
Drop it into 3rd
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