Bore vs Stroke vs Displacement
09-21-2006, 05:35 PM
#46
When you start reading through the threads for the individuals engines, you start to get a real sense of what these numbers mean and what they don't mean. Just because th LL3 has the longest stroke, doesn't mean it delivers the best bottom-end performance throughout the lower powerband. Similarly, the shortest stroke doesn't mean that it doesn't deliver on the bottom-end. How very interesting.
Anybody have anything else to add to this or comment on?
Thanks!
Anybody have anything else to add to this or comment on?
Thanks!
09-21-2006, 05:44 PM
#47
hmm
Originally Posted by rmdhawaii
When you start reading through the threads for the individuals engines, you start to get a real sense of what these numbers mean and what they don't mean. Just because th LL3 has the longest stroke, doesn't mean it delivers the best bottom-end performance throughout the lower powerband. Similarly, the shortest stroke doesn't mean that it doesn't deliver on the bottom-end. How very interesting.
Anybody have anything else to add to this or comment on?
Thanks!
Anybody have anything else to add to this or comment on?
Thanks!
09-21-2006, 05:54 PM
#48
Code:
Engine Bore Stoke Disp. ------ ----- ------ ----- Mugen X12S3 13.80 14.00 2.094
09-21-2006, 06:03 PM
#49
The other thing to consider in this is rod length, which has nothing to do with stroke. Shorter rod motors tend to have higher piston acceleration as well as having shorter TDC and BDC dwell times. This also affects the so called "low end" response.
09-21-2006, 06:15 PM
#50
Originally Posted by AMGRacer
The other thing to consider in this is rod length, which has nothing to do with stroke. Shorter rod motors tend to have higher piston acceleration as well as having shorter TDC and BDC dwell times. This also affects the so called "low end" response.
09-21-2006, 06:19 PM
#51
Originally Posted by rmdhawaii
Unfortunately, manufacturers don't seem to publish the rod length!
From what I remember the Picco motors had an ultra short rod, most novarossis a mid length rod and OSs (TRs and before) a long rod, along with the MT12 and CX 12 novarossis. My memory is pretty faulty though!
09-21-2006, 06:56 PM
#52
Originally Posted by rmdhawaii
When you start reading through the threads for the individuals engines, you start to get a real sense of what these numbers mean and what they don't mean. Just because th LL3 has the longest stroke, doesn't mean it delivers the best bottom-end performance throughout the lower powerband. Similarly, the shortest stroke doesn't mean that it doesn't deliver on the bottom-end. How very interesting.
Anybody have anything else to add to this or comment on?
Thanks!
Anybody have anything else to add to this or comment on?
Thanks!
09-21-2006, 07:03 PM
#53
Originally Posted by AMGRacer
Right, but I am sure that the RCTech readers of this topic could chime in with some responses here.
From what I remember the Picco motors had an ultra short rod, most novarossis a mid length rod and OSs (TRs and before) a long rod, along with the MT12 and CX 12 novarossis. My memory is pretty faulty though!
From what I remember the Picco motors had an ultra short rod, most novarossis a mid length rod and OSs (TRs and before) a long rod, along with the MT12 and CX 12 novarossis. My memory is pretty faulty though!
Very short
HPI 15 FE
Rossi Pixi
Short
RB X12 and all the V12 derivatives
All Novarossi .12 engines and derivatives
STS D3, D3R
RD Logics RRE S3
OS TS & TZ
Mid length
Picco 12
Mega 12
Sirio 12 all
L.Collari 12 all
Long
STS MT12
Mugen MT12
AFM
09-21-2006, 07:07 PM
#54
Originally Posted by afm
This list of engines was published by Dennis Richey long time ago on a post regarding pipe selection based on rod lenght. Of course thera are several new engines not posted, but it's a reference
Very short
HPI 15 FE
Rossi Pixi
Short
RB X12 and all the V12 derivatives
All Novarossi .12 engines and derivatives
STS D3, D3R
RD Logics RRE S3
OS TS & TZ
Mid length
Picco 12
Mega 12
Sirio 12 all
L.Collari 12 all
Long
STS MT12
Mugen MT12
AFM
Very short
HPI 15 FE
Rossi Pixi
Short
RB X12 and all the V12 derivatives
All Novarossi .12 engines and derivatives
STS D3, D3R
RD Logics RRE S3
OS TS & TZ
Mid length
Picco 12
Mega 12
Sirio 12 all
L.Collari 12 all
Long
STS MT12
Mugen MT12
AFM
09-21-2006, 07:23 PM
#56
Originally Posted by hav_lova
I just wonder, with my LL3 i always knew it didn't make the most torque out of all engines but it felt really torquey. Is that just the powerband coming on or what? Personally i wasn't a fan of it working like that
09-21-2006, 07:28 PM
#57
Thanks AFM. That's a good starting point. Now I think I need to get some actual numbers and add it to the chart I started.
09-21-2006, 07:49 PM
#58
iv found the LL3 has a higher power band than the LS3 and to some this may fell like toque i think its more mid power but the LS3 has higher top speed. i think the megas are like this low and mid power. im getin old so idono. what i mean is the LS3 coms on later then the LL3 the sirios are like this to the power comes on later
09-21-2006, 08:09 PM
#59
Originally Posted by afm
Picco Micromotori makes Mega ZX engines, and also makes LRP engines. The specs of the three are quite similar, maybe a different timing spec on each brand, but the bore end stroke identical, thought this spec sheet for the LRP .12 Spec.2 Team engine might help you
Exhaust: rear exhaust
Displacement: .12 cu in (2.11cc)
Carb: 5.5mm slide carburetor
Crankshaft: SG shaft 12.0mm/7.0mm bore
Sleeve: ABC piston and sleeve
Ports: 3+1 ports. EFRA, DMC, OFMAV, SRCC, IFMAR, ROAR race legal.
Bore: 13.8mm
Stroke: 14.0mm
Piston: CNC machined high silicium alloy
Connecting Rod: New Fork shaped aluminum using special bushings
Rpm: 3,600-42,000rpm*
Hp: 1.11hp @ 34,500 rpm *
Torque: 32.46 Oz.In. @ 34,250 *
Weight: 221g
* Specifications on 30% Nitro fuel using Mugen - Shimo pipe and header at Nitrodyne Systems Dynamometer using corrected SAE factors.
AFM
Exhaust: rear exhaust
Displacement: .12 cu in (2.11cc)
Carb: 5.5mm slide carburetor
Crankshaft: SG shaft 12.0mm/7.0mm bore
Sleeve: ABC piston and sleeve
Ports: 3+1 ports. EFRA, DMC, OFMAV, SRCC, IFMAR, ROAR race legal.
Bore: 13.8mm
Stroke: 14.0mm
Piston: CNC machined high silicium alloy
Connecting Rod: New Fork shaped aluminum using special bushings
Rpm: 3,600-42,000rpm*
Hp: 1.11hp @ 34,500 rpm *
Torque: 32.46 Oz.In. @ 34,250 *
Weight: 221g
* Specifications on 30% Nitro fuel using Mugen - Shimo pipe and header at Nitrodyne Systems Dynamometer using corrected SAE factors.
AFM
interesting.....max torque and peak power at almost the same rpm...........or am I wrong?
BTW: SAE want POWER in kW and TORQUE in N*m
.....just kidding man!
09-21-2006, 10:54 PM
#60
Originally Posted by wallyedmonds
you dont know me to well do you LOL my 2 o.s motors the piston blowed up real good like, cuz the con rods wore out realy fast and i did not change them. ONE DAY OF RUNING.
ONE DAY OF RUNING
Come to think of it, he still uses both of my old os tr engines and i know for a fact one of them has run about 20 litres! the other around 8 and both go like an OS should!