tips on building a high rpm motor

IH8DSM · 08-03-2011, 02:19 AM

so far the engine ive planned to build is this
-s4 turbo motor ran as a na bridge ported(used housings/irons)
-s5 rotors
-race rotor bearings
-rx8 eshaft
-rx8 front and rear stationary gears
-cryo treated 2mm apex seals atkins
-cryo treated side seals atkins
-solid corner seals
-new apex seal springs, corner seal springs and side seal springs
-aluminum light weight flywheel
-rotating assembly balanced

So with that being said is there anything i should lookout for when it comes to either building/running this motor, should i change or add any parts to the list?

djmtsu · 08-03-2011, 06:45 AM

Throttle body injection. I wouldn't run a carb for high RPM engines. If you are up high in the revs and running through a curve, it would suck for the bowls to empty due to the G-forces.

$$$

t_g_farrell · 08-03-2011, 07:39 AM

Do the RX8 stationary gears need to be hardened or pinned?

What about eshaft oiling mods and any mods to increase oil pressure?

IH8DSM · 08-03-2011, 10:18 AM

Mazdatrix says there already hardened but I haven't seen anywhere else that confirms this. As for oil pressure im not sure if you can do the eshaft mod with the jet or not. I'd assume so and I was going to do a racing beat adjustable oil regulator.

Dj I'm staying away from fi I might go to a weber 51 downdraft though

FC Zach · 08-03-2011, 10:43 AM

I believe the 8 stat gears are hardened and I did do the jet trick with the 8 e-shaft, you'll just need a little heat to remove the factory jets.

Here's a thread Chadwick had done a while back when he built his race motor, pretty good wright-up:
http://www.rotarycarclub.com/rotary_...spelling+myths

My5ABaby · 08-03-2011, 11:26 AM

How high do you want to go?

To_Slow · 08-03-2011, 11:31 AM

The rx8 stat gears are Case hardened so they good to go. A good mod for high RPM is to machine your rotors. Side clearanced with rotor tips also. A lightened rotors will also help with high rpm, oil jets , race bearings and all the oil mods you can think of with out dry sumping it

...

Hope that helps .
Chip U

FC Zach · 08-03-2011, 12:05 PM

Yeah, what To_Slow said, do the clearancing while the rotating assembly is sent off for balancing. Very important process for a reliable high RPM motor, as well as oil mods.

IH8DSM · 08-03-2011, 12:24 PM

Hmm lot to think on thanks for the help so far.

Zach- I remember that thread but I'll have to go read it again.

Robert- not sure gotta keep up with zach somehow

My5ABaby · 08-03-2011, 12:26 PM

2 piece e-shaft
http://www.rotaryengine.com/services/eshaftinst.htm

"It's just money." - Adler

My5ABaby · 08-03-2011, 12:29 PM

Quote:

Originally Posted by IH8DSM

Robert- not sure gotta keep up with zach somehow

Done.

j9fd3s · 08-03-2011, 12:34 PM

the Rx8 gears are hardened, in fact everything S5+ is hardened.

you want the FD oil pressure regulator + turbo oil pump. baffle plate is good too.

i'd say you're good to go to at least 9k, the guy who does the balancing should be able to give you a better idea.

weber will work fine, it takes a while to get the jetting right, but when you get it right its very nice. if its a street car a holley 4 barrel isn't a bad choice either, its a little better @part throttle, just because its a 4 barrel.

on the port, you want to keep the closing port timing around stock, intake opening should be earlier than stock, but the earlier you open the more overlap you have and the pickier the engine is going to be.

its a really FUN car when you get it setup right

IH8DSM · 08-04-2011, 07:03 AM

Yea I forgot about the baffle, thanks for all the pointers gonna start ordering more parts this weekend.

On the turbo oil pump is s4 or s5 better or are they the same

j9fd3s · 08-04-2011, 09:48 AM

Quote:

Originally Posted by IH8DSM

Yea I forgot about the baffle, thanks for all the pointers gonna start ordering more parts this weekend.

On the turbo oil pump is s4 or s5 better or are they the same

same.

the better one is the FD pump, but because they decided to feed each pump rotor separately, instead of feeding the front rotor thru the rear one. the improvement though is in the casting on the iron. if you have an S5 iron you might have the casting spot to be able to do this.

IH8DSM · 08-04-2011, 11:12 AM

I got a s4 so I guess it'll be ok, what's your opinion on reusing tension bolts vs buying new ones or studding it fczach and I have went back and forth on this topic

08-03-2011, 02:19 AM	#1
IH8DSM RCC Contributor Join Date: Mar 2008 iTrader: (0) Posts: 610 Rep Power: 17	tips on building a high rpm motor so far the engine ive planned to build is this -s4 turbo motor ran as a na bridge ported(used housings/irons) -s5 rotors -race rotor bearings -rx8 eshaft -rx8 front and rear stationary gears -cryo treated 2mm apex seals atkins -cryo treated side seals atkins -solid corner seals -new apex seal springs, corner seal springs and side seal springs -aluminum light weight flywheel -rotating assembly balanced So with that being said is there anything i should lookout for when it comes to either building/running this motor, should i change or add any parts to the list? __________________ 85 rx7 gsl-se - AA tags/ never ending project will never run

08-03-2011, 06:45 AM	#2
djmtsu My minds tellin' me no... Join Date: Feb 2008 Location: Murfreesboro, TN iTrader: (10) Posts: 4,043 Rep Power: 21	Throttle body injection. I wouldn't run a carb for high RPM engines. If you are up high in the revs and running through a curve, it would suck for the bowls to empty due to the G-forces. $$$ __________________ 1976 Mazda Cosmo RX-5 1976 Mazda Cosmo RX-5 2003 Toyota Tundra TRD 2015 Toyota 4Runner SR5

08-03-2011, 07:39 AM	#3
t_g_farrell Waffles - hmmm good Join Date: Aug 2008 Location: Huntersville, NC iTrader: (0) Posts: 757 Rep Power: 0	Do the RX8 stationary gears need to be hardened or pinned? What about eshaft oiling mods and any mods to increase oil pressure? __________________ 1980 GS stockport, Fat Nikki, RB Dual Facetfuel pumps, Holley regulator, RB Street port exhaust, 2GDFIS, MR2 MK I electric fans, 2G strut bar, relayed fans, lights and fuel pump, LEDs Project Fat Nikki Budget 12A rebuild Video setup < $30.00

08-03-2011, 10:43 AM	#5
FC Zach RCC Loves Me Not You Join Date: Mar 2008 Location: Eagleville, TN iTrader: (2) Posts: 2,267 Rep Power: 19	I believe the 8 stat gears are hardened and I did do the jet trick with the 8 e-shaft, you'll just need a little heat to remove the factory jets. Here's a thread Chadwick had done a while back when he built his race motor, pretty good wright-up: http://www.rotarycarclub.com/rotary_...spelling+myths __________________ 1993 Yamaha GTS1000 1992 Celica Turbo AllTrac 1987 RX7 Sport 1979 Yamaha G1, KM24 powered 1975 Dolmar KMS4

08-03-2011, 11:26 AM	#6
My5ABaby Sigh..... Join Date: Feb 2008 Location: Murfreesboro, TN iTrader: (6) Posts: 2,377 Rep Power: 19	How high do you want to go? __________________ 1986 Sport: 132k miles, 5A (Sapphire Blue Metallic), Tokico Blues, Racing Beat Springs, Custom LED tailights (only S4 LED tails in the world), SSR Mark II, Racing Beat exhaust, S5 black interior, Rotary Resurrection rebuild at 120k miles Community Service Manual RotorWiki "Imagination costs nothing; we could build square locomotives or fly to Mars" - Felix Wankel Yesterday is history, tomorrow is a mystery, but today is a gift. That is why it is called the "present."

08-03-2011, 10:18 AM	#4
IH8DSM RCC Contributor Join Date: Mar 2008 iTrader: (0) Posts: 610 Rep Power: 17	Mazdatrix says there already hardened but I haven't seen anywhere else that confirms this. As for oil pressure im not sure if you can do the eshaft mod with the jet or not. I'd assume so and I was going to do a racing beat adjustable oil regulator. Dj I'm staying away from fi I might go to a weber 51 downdraft though

08-03-2011, 11:31 AM	#7
To_Slow Rotary Fanatic Join Date: Feb 2008 Location: Shelby Twp MI. iTrader: (1) Posts: 315 Rep Power: 17	The rx8 stat gears are Case hardened so they good to go. A good mod for high RPM is to machine your rotors. Side clearanced with rotor tips also. A lightened rotors will also help with high rpm, oil jets , race bearings and all the oil mods you can think of with out dry sumping it ... Hope that helps . Chip U __________________ My link

08-03-2011, 12:05 PM	#8
FC Zach RCC Loves Me Not You Join Date: Mar 2008 Location: Eagleville, TN iTrader: (2) Posts: 2,267 Rep Power: 19	Yeah, what To_Slow said, do the clearancing while the rotating assembly is sent off for balancing. Very important process for a reliable high RPM motor, as well as oil mods. __________________ 1993 Yamaha GTS1000 1992 Celica Turbo AllTrac 1987 RX7 Sport 1979 Yamaha G1, KM24 powered 1975 Dolmar KMS4

08-03-2011, 12:24 PM	#9
IH8DSM RCC Contributor Join Date: Mar 2008 iTrader: (0) Posts: 610 Rep Power: 17	Hmm lot to think on thanks for the help so far. Zach- I remember that thread but I'll have to go read it again. Robert- not sure gotta keep up with zach somehow __________________ 85 rx7 gsl-se - AA tags/ never ending project will never run

08-03-2011, 12:26 PM	#10
My5ABaby Sigh..... Join Date: Feb 2008 Location: Murfreesboro, TN iTrader: (6) Posts: 2,377 Rep Power: 19	2 piece e-shaft http://www.rotaryengine.com/services/eshaftinst.htm "It's just money." - Adler __________________ 1986 Sport: 132k miles, 5A (Sapphire Blue Metallic), Tokico Blues, Racing Beat Springs, Custom LED tailights (only S4 LED tails in the world), SSR Mark II, Racing Beat exhaust, S5 black interior, Rotary Resurrection rebuild at 120k miles Community Service Manual RotorWiki "Imagination costs nothing; we could build square locomotives or fly to Mars" - Felix Wankel Yesterday is history, tomorrow is a mystery, but today is a gift. That is why it is called the "present."

08-03-2011, 12:34 PM	#12
j9fd3s Rotary Fanatic Join Date: Mar 2008 iTrader: (0) Posts: 123 Rep Power: 17	the Rx8 gears are hardened, in fact everything S5+ is hardened. you want the FD oil pressure regulator + turbo oil pump. baffle plate is good too. i'd say you're good to go to at least 9k, the guy who does the balancing should be able to give you a better idea. weber will work fine, it takes a while to get the jetting right, but when you get it right its very nice. if its a street car a holley 4 barrel isn't a bad choice either, its a little better @part throttle, just because its a 4 barrel. on the port, you want to keep the closing port timing around stock, intake opening should be earlier than stock, but the earlier you open the more overlap you have and the pickier the engine is going to be. its a really FUN car when you get it setup right

08-04-2011, 07:03 AM	#13
IH8DSM RCC Contributor Join Date: Mar 2008 iTrader: (0) Posts: 610 Rep Power: 17	Yea I forgot about the baffle, thanks for all the pointers gonna start ordering more parts this weekend. On the turbo oil pump is s4 or s5 better or are they the same __________________ 85 rx7 gsl-se - AA tags/ never ending project will never run

08-04-2011, 11:12 AM	#15
IH8DSM RCC Contributor Join Date: Mar 2008 iTrader: (0) Posts: 610 Rep Power: 17	I got a s4 so I guess it'll be ok, what's your opinion on reusing tension bolts vs buying new ones or studding it fczach and I have went back and forth on this topic __________________ 85 rx7 gsl-se - AA tags/ never ending project will never run