drool new rotor and stat gears drool
03-27-2006, 11:32 PM
#11
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Join Date: Oct 2003
Location: Canada
Posts: 3,502
Originally Posted by madaz matt' post='810116' date='Mar 26 2006, 02:04 AM
well the place that makes them (xtremerotaries) recon that the factory ones breack all the time
That's horseshit, what kind of applications do they claim they "break all the time" in?
03-28-2006, 06:53 AM
#12
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Join Date: Dec 2002
Location: fredneck MD
Posts: 4,107
I think you may also be missing one point..
on very high HP, high boost applications you will encounter a large amount of eshaft flex, which just as it sounds, does bad things.
If the rotors are more stable in their orbit, perhaps this flex will be cut down a small amount.
Remember how close the tolerances are in this engine, It doesent take much to make a difference...
I agree that the stock ones are fine for anyone running a sane amount of HP and RPM, but mabye they do some good...
on very high HP, high boost applications you will encounter a large amount of eshaft flex, which just as it sounds, does bad things.
If the rotors are more stable in their orbit, perhaps this flex will be cut down a small amount.
Remember how close the tolerances are in this engine, It doesent take much to make a difference...
I agree that the stock ones are fine for anyone running a sane amount of HP and RPM, but mabye they do some good...
03-28-2006, 07:26 AM
#13
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Join Date: Jun 2004
Posts: 524
Originally Posted by rfreeman27' post='810562' date='Mar 28 2006, 04:53 AM
I think you may also be missing one point..
on very high HP, high boost applications you will encounter a large amount of eshaft flex, which just as it sounds, does bad things.
If the rotors are more stable in their orbit, perhaps this flex will be cut down a small amount.
That sounds a bit backwards to me, the eccentric shaft flexing being due to the uneven way the weight on it is counterbalanced. The rotors "get unstable" because of the e-shaft, not the other way around.
Find a way to mount the counterweights in the middle of the rotors and flex will be all but gone.
03-28-2006, 10:07 AM
#14
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Join Date: Nov 2002
Posts: 3,108
The most important factor in performance of a gear train is how the gears are matched to each other.
A dirty gear box with unmatched gears due to slight difference in size caused by tolerances will cause certain teeth to be loaded more than others. The accuracy and precision of each tooth will also determine how the gears will mesh and how the load is distributor on the individual tooths.
For me if I had the money I would by 100 sets of mazda stat gears and rotor gears and try to make 20 or so matched pairs. With the other ones going into the scrapper or used in less demanding applications.
A dirty gear box with unmatched gears due to slight difference in size caused by tolerances will cause certain teeth to be loaded more than others. The accuracy and precision of each tooth will also determine how the gears will mesh and how the load is distributor on the individual tooths.
For me if I had the money I would by 100 sets of mazda stat gears and rotor gears and try to make 20 or so matched pairs. With the other ones going into the scrapper or used in less demanding applications.
04-02-2006, 09:06 PM
#17
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Thread Starter
Join Date: Feb 2006
Posts: 38
Originally Posted by G_RIDE' post='811565' date='Apr 2 2006, 03:16 PM
they should design a new center housing with a stationary gear and put a gear on both side of the rotor
this is what guru said about the centre bearing
GURU Racing can supply a two piece eccentric shaft for a 13B engine that substantially reduces eccentric shaft flex as well as providing extra bearing surface area. The end result is increased horsepower with substantially increased reliability!
The unit is especially designed for exceptionally high horse-powered and high revving engines, where bearing fatigue and crank flex is detrimental to engine reliability.
Technical Specifications:
Applications:
Currently delivered for all 13B Mazda engines
Suits Mazda RX7 models (Generation 1 - 3, Series I - VI)
Suitable for road and race applications
[attachment=37372:attachment][attachment=37371:attachment][attachment=37370:attachment]
General:
30% more bearing surface area than a standard 13B Shaft
Helps reduce bearing failure & fatigue on high boosted turbo engines
Helps eliminate crankshaft flex at high rpms
Reduces crankshaft flex therefore rotor clearance can be set to a minimum and seal clearances can be set tighter for increased horsepower
Stronger
1.2kg lighter than a "standard" eccentric shaft
Kit supplied with all components (including needle roller bearing) and specifications for centre housing machining to fit the centre bearing.
13B 2 piece eccentric shaft with centre bearing $2750.00 + GST
04-03-2006, 09:57 AM
#18
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Join Date: May 2002
Location: California
Posts: 22,465
Originally Posted by madaz matt' post='811667' date='Apr 2 2006, 07:06 PM
The unit is especially designed for exceptionally high horse-powered and high revving engines, where bearing fatigue and crank flex is detrimental to engine reliability.
yes but we're not there yet
