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What are some ways to bring up the redline?

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Old Jan 20, 2007 | 02:50 AM
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What are some ways to bring up the redline?

What are some ways to raise the incredible redline of the fd? (Besides going n/a an 20B)

I heard lightweight (carbon) driveshafts work but they aren't a big difference to stock so I don't want to just throw away 950$. Would flywheel or adding light weight rotors workat all? Do you guys have any other methods besides these?
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Old Jan 20, 2007 | 05:26 AM
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im not sure on this but i think that once you go any higher above the already hig redline then youd just start loosing power... not hure tho, some one confirm...
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Old Jan 20, 2007 | 06:38 AM
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Hardend stationary gears, clearenced rotors, 3 window bearings, lightend rotors, dry-sump, electric water pump, dowell pinning, light flywheel and driveshaft, 2 peice E-shaft. These will all make your motor able to rev higher, but its more your ports if your NA, or your turbo if your not, that matters most. Who cares if you can rev to 10k, if you stop making power at 8?
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Old Jan 20, 2007 | 06:40 AM
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I think the most important thing is having it all balanced perfectly
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Old Jan 20, 2007 | 06:41 AM
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Your car is turbocharged. The flow characteristics mean that higher revs are at lower output, and therefore this exercise is not worth the effort.

Talk to the NA guys if you really want to raise the redline. You'll need better balancing in all rotating components, and I think they also change the bearing clearances, bearing types, etc.

Dave
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Old Jan 20, 2007 | 08:48 AM
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The biggie for high RPM use is harmonics - past 8500 RPM, tension bolts can come loose and a motor that isn't balanced well can shake itself apart.

The other biggie is the accessories - water pumps and alternators aren't designed to be spun that fast. You need to change pullies on them, maybe to something even more underdriven than the commonly available ones.

Everyone has a good point - the motor has to be set up around a higher redline. Most times past 8000 RPM the motor is just losing power. Bigger ports help that out, as does a properly-sized turbo.

In general, it's OK to accidentally get into the red - I've had my TII to 10,000 on accident before, no big deal. Building for a high RPM is moreso for prolonged high-RPM use on a race track where you will be at that RPM for half hour/hour track sessions.

If you just want cool points with your friends, get a high RPM tach and say the engine will do it . This is one place where the rotary does well - many piston engines grenade themselves if you go far past redline. Rotaries don't care if you go there on accident. I've known 1st gen guys that have run the tach all the way back around to the zero mark!

Dale
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Old Jan 20, 2007 | 09:21 AM
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Originally Posted by Fd3s4e
What are some ways to raise the incredible redline of the fd? (Besides going n/a an 20B)

I heard lightweight (carbon) driveshafts work but they aren't a big difference to stock so I don't want to just throw away 950$. Would flywheel or adding light weight rotors workat all? Do you guys have any other methods besides these?
Most of the lightweight stuff (flywheels, driveshafts, etc.) do not really raise the redline. They get you to it quicker by reducing the rotating mass of the engine and driveline, the same way reducing the car's weight allows you to accelerate quicker.

As mentioned in the previous posts, significantly raising the redline is a more complicated, expensive, and not always very productive process.

Dave
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Old Jan 20, 2007 | 09:32 AM
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Arrow

Check the Rotary Performance section for great technical information :

https://www.rx7club.com/rotary-car-performance-77/12000rpm-crank-451889/
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Old Jan 20, 2007 | 09:34 AM
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Why?
I want to know why you want to do this.
Seriously.
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Old Jan 20, 2007 | 12:21 PM
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Originally Posted by Mahjik
Check the Rotary Performance section for great technical information :

https://www.rx7club.com/showthread.php?t=451889
Thanks once again!
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Old Jan 20, 2007 | 12:30 PM
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All the basic answers are here in this thread I think. The bottom line is.... WHY? 99% of FDs dynos that I've seen don't get better over 8000 or 8500 RPM - they get worse.

Going from 8000 to a 9000 redline dramatically increases the forces present in the engine, and I'm sure that in 99% of cases, you're actually going to be SLOWER than if you just shifted at around 8000.
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Old Jan 20, 2007 | 02:24 PM
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Many of the posts have already touched on the (many) relevant issues w/ achieving a higher redline. But also keep in mind that the engine internals are NOT the only issue you'd be facing; (as Dale mentioned) not only are the tension bolts not designed to withstand that high of a load, but the *housings themselves* will flex at higher rpms. Yes, the housings.

~Ramy
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Old Jan 20, 2007 | 08:27 PM
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Redline in modern engines is not the same as in older engines. Redline in older engines was basically a never exceed rpm. In modern engines its the maximum rpm shift point. It really is unrelated to never exceed rpms. So in-short. To find your shift point (redline) you need to have your car on a dyno.
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Old Jan 20, 2007 | 08:38 PM
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Get a bridgeported motor and a GT42R......... My car kept makingn more and more power even at 7800rpms.
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Old Jan 20, 2007 | 09:15 PM
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Moved Thread
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Old Jan 20, 2007 | 09:19 PM
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I wish I would rev my motor to 20k. That would be the sweetest thing ever. Cause you guys all know once you break 10k you automatically reach lightspeed.
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Old Jan 20, 2007 | 09:40 PM
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Originally Posted by Cgotto6
I wish I would rev my motor to 20k. That would be the sweetest thing ever. Cause you guys all know once you break 10k you automatically reach lightspeed.
THEY'VE GONE TO PLAID!!!
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