what is the benefits of the rx8 eshaft?
#1
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what is the benefits of the rx8 eshaft?
well whats going on guys? well as u know i blew my motor and now im trying to turn it into a beast...well i was reading about the rx8 e-shaft, and what is the benefit of putting a rx8 eshaft into a S5 tII rx7 motor and would it just fit in or would i have to get the staionary gears also?
thanks Marco
thanks Marco
#5
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i know
thank you Marco
#6
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Being that it's lighter it would have the same effect of switching to a lightweight flywheel, but it won't be near as noticeable, if at all. Switching to the lightweight flywheel, or to a much less extent, switching to this e-shaft, would allow you to rev faster since there is less weight to move.
I was thinking about this too, but I'm not sure it's worth the money for as little weight as it cuts down, and even moreso as little difference as it makes.
I was thinking about this too, but I'm not sure it's worth the money for as little weight as it cuts down, and even moreso as little difference as it makes.
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#9
The renesis is the next generation of E-shafts, but my guess is they didn't make it weaker. Since the rotors have a 1200 higher redline on the renesis, its probably stronger. So it should work with no problems on an S5 TII.
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Yeah I think it is stronger actually, but that was never a weak point with rotaries anyway, so I'm spending my money on something that's going to make more of a difference. By all means, if I had money to throw around, I'd be going for the RX-8 e-shaft, lightweight rotors, the whole 9, but I don't at this time. Someday I do hope to run all that stuff though. Good luck with your builds guys.
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Yeah I think it is stronger actually, but that was never a weak point with rotaries anyway, so I'm spending my money on something that's going to make more of a difference. By all means, if I had money to throw around, I'd be going for the RX-8 e-shaft, lightweight rotors, the whole 9, but I don't at this time. Someday I do hope to run all that stuff though. Good luck with your builds guys.
#16
I remember hearing the Renesis e-shaft can be found at a lower price than a 13B e-shaft, so if you need another e-shaft I don't any obvious reasons why you shouldn't go with the Renesis e-shaft...
but just for .6 lbs difference? ...you can lose or gain a few pounds of water in just a day, I don't see .6 lbs making a noticeable difference unless you can find 50 other little things that weigh ~.5 lb to remove...
but just for .6 lbs difference? ...you can lose or gain a few pounds of water in just a day, I don't see .6 lbs making a noticeable difference unless you can find 50 other little things that weigh ~.5 lb to remove...
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if you're on a budget, the eshaft rarely wears out, it would be better to spend the dollars in rotor housings, or balancing or an ecu, than it would be to save half a pound on the rotating assembly.
however if you need an eshaft, or already have a really really tight well built engine, then rx8 shaft is the way to go
#20
Originally Posted by TehMonkey
.6lbs of rotating mass is alot different than .6lbs of static weight.
The effect of the weight reduction is directly proportional to the distance the weight is from the centerline.
Reducing the weight from a large diameter object like a flywheel will have a noticeable effect.
Reducing a small diameter part like the eshaft will have much less...in fact, I would posit that you could never tell.
If the newer shaft is better in some other aspect then go for it, but I don't see how it could be justified on the basis of weight reduction alone.
#21
The loads seen inside an engine are HUGE. Given that stress on a rotating object is not calculated in a linear fashion, any amount of weight savings on reciprocating mass is sure to pay big dividends with regard to engine durability and high RPM operation. Safer higher RPM operation means more horsepower, and more hp means faster acceleration.
#22
The loads seen inside an engine are HUGE. Given that stress on a rotating object is not calculated in a linear fashion, any amount of weight savings on reciprocating mass is sure to pay big dividends with regard to engine durability and high RPM operation. Safer higher RPM operation means more horsepower, and more hp means faster acceleration.
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Some of what restricts RPM is balance IMO. .6lb less rotating mass means .6lbs of mass that isn't potentially unbalanced. And because of the RX-8's higher rev limit, I would imagine Mazda put more work/technology into balancing them properly. So, with a front/rear stat gear and e-shaft... It SHOULD be a direct swap. Though nothing beats having your entire rotating assembly professionally balanced. E-Shaft, Rotors, Counterweights...... Its just f-ing expensive.
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Originally Posted by SpeedOfLife
the Renesis rotors are lighter than any of the 13B rotors though, so the stressful forces on Renesis e-shaft IN a Renesis at redline may still be less than the stressful forces on it with 13B rotors at a 13B redline (which varies between years and TII/NA, I know).
Originally Posted by clokker
The effect of the weight reduction is directly proportional to the distance the weight is from the centerline.
Reducing the weight from a large diameter object like a flywheel will have a noticeable effect.
Reducing a small diameter part like the eshaft will have much less...in fact, I would posit that you could never tell.
Reducing the weight from a large diameter object like a flywheel will have a noticeable effect.
Reducing a small diameter part like the eshaft will have much less...in fact, I would posit that you could never tell.
clokker, I thought your avatar was Tom Servo for a minute, haha. I've had MST3K on the brain lately.
#25
I didn't know the RX-8 rotors were lighter too. That might change my mind a little, haha. How much lighter are we talking? My current e-shaft is in good shape but I'm currently looking for rotors anyway. I probably still won't have the money for a new set though, and I highly doubt someone would be selling a used set already, haha.