233 rwhp dyno sheet
07-08-2011, 01:38 AM
#176
If you're comparing two flywheels, you might have flywheel A that is 5kg and flywheel B that is 6kg, which one will spool quicker thus giving you a quicker acceleration over the stock components? not enough info! It's possible that the 6kg flywheel could have the majority of it's weight concentrated near the axis of rotation and the 5kg flywheel could have it's concentration of mass near the edges of the flywheel, and this could result in the heavier flywheel being better.
There is really only a very narrow range of radii on the flywheel where mass can be removed and your 6kg example will simply have more of it in the same spot where the 5kg unit has removed it.
The flywheel is only 225mm or so in diameter. Almost all of the "r" in the MOI formula sits over the r/.7 area. Even the PP falls in that same part of net "r"
Oh, it was funny alright, just not in the way it was "about" me.
That is why I quoted it. lol
07-08-2011, 10:23 AM
#177
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But the reality is that it can't, and that is the point.
There is really only a very narrow range of radii on the flywheel where mass can be removed and your 6kg example will simply have more of it in the same spot where the 5kg unit has removed it.
The flywheel is only 225mm or so in diameter. Almost all of the "r" in the MOI formula sits over the r/.7 area. Even the PP falls in that same part of net "r"
Oh, it was funny alright, just not in the way it was "about" me.
That is why I quoted it. lol
There is really only a very narrow range of radii on the flywheel where mass can be removed and your 6kg example will simply have more of it in the same spot where the 5kg unit has removed it.
The flywheel is only 225mm or so in diameter. Almost all of the "r" in the MOI formula sits over the r/.7 area. Even the PP falls in that same part of net "r"
Oh, it was funny alright, just not in the way it was "about" me.
That is why I quoted it. lol
07-08-2011, 11:26 AM
#178
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I've never actually seen the rx8 flywheel, yet. I was just talking in general about flywheels, but based on the lengths mazda has taken to squeeze every ounce of performance out of the car in other areas (intake, etc.) it makes sense that they would do the same for such an important component as the flywheel.
I think the RX-8 market could benefit by someone making one of these scooby doobies. It could still easily handle the power loads and should be OK for the street and track crowd. You may have to replace it a little more often but a clutch is a consumable like brake pads, tires, etc.
Here is a link which reveals the standard clutch sizes that people use in racing:
http://www.hrpworld.com/index.cfm?tp...ction=category
07-08-2011, 11:55 AM
#179
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Handle FI numbers? or are we talking only NA (as I know that's where you specialize)... because even if we have a 230whp FI rx8 vs a 230whp NA rx8 the torque numbers aren't the same...
07-08-2011, 12:00 PM
#180
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HP is a function of torque. If you have a 230whp NA and a 230whp FI where those peak numbers are at the same RPM, then the torque at that RPM is the same.
Agreed, in general, you will see a different torque curve for each.
If the FI peaks at 230 at a lower RPM, they will have more torque at their peak power RPM than the NA, and vise versa. IF the FI peak torque is higher, then it means that the torque is dropping off faster than the NA to have the same power.
07-08-2011, 12:15 PM
#181
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Yes I completely understand and didn't want to go into great depths.... moral of the story is with FI there will be more stress/wear and tear on the clutch.... and besides most FI people are hitting more than 230whp anyway.... I guess what I should have asked is up to what HP/Tq would Eric expect this welded assembly to withstand?
07-08-2011, 12:22 PM
#183
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I don't think that's where he was going..... he was more just questioning the depth of R&D that went into the Rx8 Flywheel
You guys sound like little school girls with all your bantering
except nowhere near as good looking
07-08-2011, 12:27 PM
#184
Most of that research and development went towards streetability anyway, performance assemblies are way different but would make a normal customer hate the car.
07-08-2011, 01:18 PM
#187
I don't know is a smaller single disk clutch assembly is practical on a street driven car. If you reduce the size of the clutch disk, you have to use a different friction material and a higher clamping force on that clutch disk. The lack of clutch slip and higher effort required to press the clutch, in traffic, would make this undesirable. This is the same reason some people prefer an automatic transmission over a manual.
07-08-2011, 01:29 PM
#188
I don't know is a smaller single disk clutch assembly is practical on a street driven car. If you reduce the size of the clutch disk, you have to use a different friction material and a higher clamping force on that clutch disk. The lack of clutch slip and higher effort required to press the clutch, in traffic, would make this undesirable. This is the same reason some people prefer an automatic transmission over a manual.
The big problem is that the rotary motor rotating assembly has very low MOI on its own (without the flywheel) and very low torque at idle, so keeping the motor moving at low RPMs gets more and more difficult as you reduce the MOI of the flywheel/clutch.
Here's the "tidbit" for you that like Eric's style of delivering such things:
"Why smaller? - Why not larger?"
No, there is a lot of good stuff here, if you read between the lines.
07-08-2011, 01:38 PM
#189
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Just curious, I've noticed an incredibly wide variation between 8s and the amount of pedal pressure needed on the OEM clutch. Mine being one of the hardest I've felt, and a friend having one of the lowest (felt like what a 100hp economy car would have). And plenty in between. Is the balancing point of the lever-arm so precise that manufacturing tolerances can make so big of a change?
07-08-2011, 05:25 PM
#190
Dunno. I've noticed a WIDE variance in pedal feel as well, even amongst totally stock setups.
Could be all kinds of interference and friction in the pedal and release bearings, wear at the contact points on the pressure plate or even worn friction material in the finger springs.
Could be all kinds of interference and friction in the pedal and release bearings, wear at the contact points on the pressure plate or even worn friction material in the finger springs.
07-08-2011, 06:35 PM
#191
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You'd be very surprised what those little clutches can take with careful selection and setup, but the problem is not many road/track guys want to spend 3k on a clutch setup that'll only shave tenths off here and there.
07-09-2011, 05:08 AM
#192
FWIW I was able to adapt a Tilton 7.25" inch twin disk rally clutch to a stock size lightened flywheel while still retaining the stock throw out bearing, fork etc. Works quite well. The clutch assembly runs about $900 and the flywheel I think was another $300 or $400 or so. I think this is very similar to what Erik Meyer used but the flywheel I used it not as extremely lightened and I retained the stock clutch release mechanisms. I actually do some rally racing with the car so I wanted it somewhat streetable as well - it has a fast engagement but once you get used to that it's quite streetable.
I worked with AASCO Performance in Anaheim, CA to get it built. They have the specs on file now and I'm sure they'd be happy to make one for anyone who asks.
I worked with AASCO Performance in Anaheim, CA to get it built. They have the specs on file now and I'm sure they'd be happy to make one for anyone who asks.
07-09-2011, 05:13 AM
#193
I think the RX-8 market could benefit by someone making one of these scooby doobies. It could still easily handle the power loads and should be OK for the street and track crowd. You may have to replace it a little more often but a clutch is a consumable like brake pads, tires, etc.
07-09-2011, 07:45 PM
#196
Ok, trying to sum up the original post to now, if I correctly have followed the key elements:
It's possible to have impressively high (for a NA Renesis) wheel horsepower and torque levels if the rest of the driveline has less parasitic drag than our stock drive line, therefore, in the quest for improvements, we ought not merely look at the engine; but the entire drive line.
Assuming that is the key take-away from the eight pages this discussion has so far amassed, are there any vendors offering more efficient but viable alternatives (clutch, transmission, differential, CV joints, etc)? Obviously, dropping in a Hewland 6 speed sequential transaxle is not a simple matter, although I am curious as to its feasibility, given the layout of the RX-8.
It's possible to have impressively high (for a NA Renesis) wheel horsepower and torque levels if the rest of the driveline has less parasitic drag than our stock drive line, therefore, in the quest for improvements, we ought not merely look at the engine; but the entire drive line.
Assuming that is the key take-away from the eight pages this discussion has so far amassed, are there any vendors offering more efficient but viable alternatives (clutch, transmission, differential, CV joints, etc)? Obviously, dropping in a Hewland 6 speed sequential transaxle is not a simple matter, although I am curious as to its feasibility, given the layout of the RX-8.
07-09-2011, 07:50 PM
#197
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There is only 1 item that I am aware of that fits your criteria longpath, the REmedy water pump. though it's marketed as a reliability mod (rightfully so) and not a power mod, it does not struggle to push the water around as much as the OEM one, and it's been shown to have a positive effect on whp dyno charts.
At least from the vendors serving the community as a whole. I'd expect that there is a vendor offering a more efficient part for every single part of the drivetrain if you include price ranges that most of us simply can not pay.
At least from the vendors serving the community as a whole. I'd expect that there is a vendor offering a more efficient part for every single part of the drivetrain if you include price ranges that most of us simply can not pay.
07-10-2011, 07:12 AM
#199
There is only 1 item that I am aware of that fits your criteria longpath, the REmedy water pump. though it's marketed as a reliability mod (rightfully so) and not a power mod, it does not struggle to push the water around as much as the OEM one, and it's been shown to have a positive effect on whp dyno charts.
At least from the vendors serving the community as a whole. I'd expect that there is a vendor offering a more efficient part for every single part of the drivetrain if you include price ranges that most of us simply can not pay.
At least from the vendors serving the community as a whole. I'd expect that there is a vendor offering a more efficient part for every single part of the drivetrain if you include price ranges that most of us simply can not pay.
07-10-2011, 08:09 AM
#200
I'm assuming I'd have to tear down my differential and transmission so I could send the parts out for coating. For CV joints, I doubt I could get it back together again if I took it apart. Are there companies that makes CV joints that have the kind of friction fighting coatings and treatments we have discussed?