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TrEsPaSS
RTR Semi Pro
USA
182 Posts |
 Posted - 09/13/2009 : 01:16:30 AM
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Please excuse my ignorance, I'm a noob. I am not good on the spec side of things but learning. Can someone explain the HP/rpm thing to me (layman's terms)? Reason being, the .32 blasts the MV out of the water, what would the others do?
Here are the specs that I am wondering about:
Dynamite .32 = HP: 1.18 @ 28,000 RPM
Rossi .21 = HP: 2.9 @ 42,000 RPM
Pro .21 = HP: 2.7 @ 39.000 RPM
OS Max 21VZ-M = HP: 2.5 @ 33,000 RPM
Leave out the price..which would you put in your ride?
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Edited by - TrEsPaSS on 09/13/2009 01:21:26 AM |
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JOSEPHKING1971
RTR Semi Pro
USA
452 Posts |
Posted - 09/13/2009 : 07:22:39 AM
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ROSSI 2.9 @42000 IS STRONG FOR TAKE OFF AND 42000 RPM SO ITLL GO WICKED FAST THATS ROSSI
YOUR 32 was mod? but as far as ive heard theres no class for it so no racing!
butif your not going racing then use it (i would).
ok so hp shoots ya off the line and rpm is top speed i hope some this helps. |
JOE KING  |
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Billy
CERTIFIED ZONER
USA
2998 Posts |
Posted - 09/13/2009 : 10:27:24 AM
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| rossi 21. 2.9 is great hp, but its the 42,000 rpm im looking at. when it comes to boat you want little hp and alot of rpm. cars and trucks need alot of hp not so much rpm |
BILLY BAD ASS
1/8 Miss Budweiser zen 26
1/12 Mod Miss Budweiser go.18
1/12 Mod Miss Budweiser aqu.18
1/12 Pro Boat Miss Sundance aqu.18
MRP Electric Tunnel
31" Prather mono OS.21
41" Prather mono KB.67
42" Custom Wood John Finch Wild Thing MAC.67
http://www.youtube.com/user/MrRckings |
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rome
RTR Semi Pro
USA
382 Posts |
Posted - 09/13/2009 : 10:30:08 AM
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| why when the motor get bigger the rpms get smaller |
its good to be fast |
Edited by - rome on 09/13/2009 10:35:51 AM |
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opio
Moderator
2017 Posts |
Posted - 09/13/2009 : 11:16:55 AM
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| well the hp come into play if you slow your boat down, you need the hp to get up on on plane, but that can be solved also with the right prop, lots of rpm's turn the prop really fast so more speed! but if your prop is to big, low hp wont let the motor spin those big rpm's, its a big balancing act! |
Jeremy Glance
District 8 Namba
JAE .12 Mod cvr-m .18
JAE .12 ( Hull only )
Miss Veges Mod Aqu .18
Miss Attitude Mod STS/NR .21
Whiplash .21 ( Hull only )
Whiplash .21 ( Hull only )
Sniper 3.5 ( Hull only )
Muas 40 ( Hull only )
I sweat during peace, so they don't bleed during war.
All gave some, some gave All. |
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Billy
CERTIFIED ZONER
USA
2998 Posts |
Posted - 09/13/2009 : 6:23:58 PM
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| and it sucks doing the balancing act on a boat. sometimes it takes a awhile |
BILLY BAD ASS
1/8 Miss Budweiser zen 26
1/12 Mod Miss Budweiser go.18
1/12 Mod Miss Budweiser aqu.18
1/12 Pro Boat Miss Sundance aqu.18
MRP Electric Tunnel
31" Prather mono OS.21
41" Prather mono KB.67
42" Custom Wood John Finch Wild Thing MAC.67
http://www.youtube.com/user/MrRckings |
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opio
Moderator
2017 Posts |
Posted - 09/13/2009 : 6:39:24 PM
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quote:
Originally posted by rome
why when the motor get bigger the rpms get smaller
I would guess that small motors do not have the power to pull a big prop so they need lots of rpm's to turn little props really fast to make speed, now a big motor with lots of torque can turn a big prop and not need the rpm's to get the speed. (i think lol) |
Jeremy Glance
District 8 Namba
JAE .12 Mod cvr-m .18
JAE .12 ( Hull only )
Miss Veges Mod Aqu .18
Miss Attitude Mod STS/NR .21
Whiplash .21 ( Hull only )
Whiplash .21 ( Hull only )
Sniper 3.5 ( Hull only )
Muas 40 ( Hull only )
I sweat during peace, so they don't bleed during war.
All gave some, some gave All. |
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TrEsPaSS
RTR Semi Pro
USA
182 Posts |
Posted - 09/13/2009 : 7:10:17 PM
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| is that the reason that i have to rocket the boat into water with a high pitch prop? then when it hits plane I get an 8foot rooster tail and its off like a bat outta hell. |
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opio
Moderator
2017 Posts |
Posted - 09/13/2009 : 7:15:58 PM
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| I would think so, your motor seems to like high rpm's so ya really gotta give it a toss right? |
Jeremy Glance
District 8 Namba
JAE .12 Mod cvr-m .18
JAE .12 ( Hull only )
Miss Veges Mod Aqu .18
Miss Attitude Mod STS/NR .21
Whiplash .21 ( Hull only )
Whiplash .21 ( Hull only )
Sniper 3.5 ( Hull only )
Muas 40 ( Hull only )
I sweat during peace, so they don't bleed during war.
All gave some, some gave All. |
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Billy
CERTIFIED ZONER
USA
2998 Posts |
Posted - 09/13/2009 : 7:35:33 PM
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| yes with the wicked pitchd 3 blade i run on my miss budweiser, you realy have to give her a big toss. if its not enough toss its like the prop just wont catch the water and move the boat. |
BILLY BAD ASS
1/8 Miss Budweiser zen 26
1/12 Mod Miss Budweiser go.18
1/12 Mod Miss Budweiser aqu.18
1/12 Pro Boat Miss Sundance aqu.18
MRP Electric Tunnel
31" Prather mono OS.21
41" Prather mono KB.67
42" Custom Wood John Finch Wild Thing MAC.67
http://www.youtube.com/user/MrRckings |
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TrEsPaSS
RTR Semi Pro
USA
182 Posts |
Posted - 09/13/2009 : 8:24:50 PM
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quote:
Originally posted by opio
I would think so, your motor seems to like high rpm's so ya really gotta give it a toss right?
The M445 and X645 jet right off like a rocket. I have a 1945 that has to be slingshot into the drink, but man when it hits a plane it really takes off, unfortunatly it will bog out when I lose mometum or spin. |
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TrEsPaSS
RTR Semi Pro
USA
182 Posts |
Posted - 09/17/2009 : 9:10:03 PM
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| Can't seem to get the dynamite over 46mph, I have read about "removing the shim" what does this mean? |
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Topic |
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HP vs. RPM?
