nitro engine ?
04-23-2006, 09:53 AM
#1
nitro engine ?
ok why is it that OS and other companies call there motors .18, .21, etc. and traxxas has 2.5 and 3.3.
if you dont understand what im getting to. its that others are under 1 they are a decimal.
if you dont understand what im getting to. its that others are under 1 they are a decimal.
04-23-2006, 10:33 AM
#2
2.5 is cubic centimeters as opposed to the usual .15 cubic inches......
why they do it that way?.... my guess is marketing..
their engines also have a one of a kind shaft, no idea why they did that.....
other than to try and keep you from using other engines with their kits.
why they do it that way?.... my guess is marketing..
their engines also have a one of a kind shaft, no idea why they did that.....
other than to try and keep you from using other engines with their kits.
04-23-2006, 10:42 AM
#3
thanks
ok yesterday i was at the track and 2 guys had revos. one with the 3.3 traxxas adn they other was running i think he said 0s .18mt or something like that. what is faster.
04-23-2006, 10:49 AM
#4
Originally Posted by rangered
ok yesterday i was at the track and 2 guys had revos. one with the 3.3 traxxas adn they other was running i think he said 0s .18mt or something like that. what is faster.
you were at the track with both of them, so you would know better as to which one was faster...
04-24-2006, 04:21 PM
#5
Ive heard good things about the os.18 but i would assume that the 3.3 is most likely the faster engine simply because of displacement(i know that more displacement doesnt mean more speed) and what traxxas has said about it. although, from what ive heard, traxxas does have a reputation for engines that are fairly difficult to tune and tend to overheat so i wouldnt recomend you go out and but the 3.3. buy the os.18 is probably the better all around engine.
04-24-2006, 05:05 PM
#6
The OS .18TM is apparently quite a powerful engine with a very usefull powerband, mine will be arriving form Tower tomorrow, I am putting it into my TNX with a revo slipper/spur setup. I am currently using the OS .18 CV-RX I will keep you posted on how it goes.
04-24-2006, 11:32 PM
#7
traxxas names their engines by 3.3 and 2.5 so they look "big" and tricks u into buying there engine over the others but its only a little .15 and a .18 size engine...but..smaller cc engine have MORE RPM than bigblock engines....a .12 size engine will outrun a .28 in the high rpm but the .28 will have aLOT more torque
big engine = lots of torque/less top RPM/more HP
small enigne = less torque/more top RPM/less HP
but there are some big block engines like the collari .25 and the .32 wich produce over 36,000 RPM...i think lol..i know hte .25 produces around 40,000 somthing
big engine = lots of torque/less top RPM/more HP
small enigne = less torque/more top RPM/less HP
but there are some big block engines like the collari .25 and the .32 wich produce over 36,000 RPM...i think lol..i know hte .25 produces around 40,000 somthing
04-25-2006, 12:08 AM
#8
What about the Savage 4.6. You have it in your signature? It is only a .28, all company's do it now. The 3.3 is a .20ci engine as well, the biggest of the small blocks. Big engine doesn't mean faster truck either.
04-26-2006, 01:32 AM
#9
Originally Posted by AUSTNX
What about the Savage 4.6. You have it in your signature? It is only a .28, all company's do it now. The 3.3 is a .20ci engine as well, the biggest of the small blocks. Big engine doesn't mean faster truck either.
05-04-2006, 07:45 AM
#10
Power and RPM ratings on engines are misleading in many cases, because there isn't an industry standard dyno yet. However, you can still dyno test engines and do a fair test to indicate which engine is - for want of a better word - best. There are some nice comparison test results which yield a few suprises! Check out the STS thread.
Nitro engines always used to be measured in cubic inches - .20, .21, .40, .60, .90, 1.10 etc.
Traxxas have been giving their engines in CC's, more recently HPI have followed suit.
2.5, 3.3, 3.5, 4.1, 4.6 etc
Initially, I'm quite convinced it was a clever marketing move as PSO mentioned.
Conversion is quite straight forward. There are 2.54 cm in 1". As we are talking about cubic measurements, you have to do every thing to the power of 3.
1.0 Cubic Inch = 2.54 x 2.54 x 2.54 = 16.39cc
.25 Cubic inch = .25 x 16.39 = 4.1
Converting it the other way around is a simple division excercise:
23cc = 23 / 16.39 = 1.40 cui
5cc = 5 / 16.39 = .30 cui
There aint no replacement for displacement......alledgedly!
Besides Turbos, Superchargers, multi valve engine technology, ECU technology that is!!
In the context of nitro engines, we have other factors like intake timings, compression ratio, side or rear exhausts, number of ports, crank, rod and piston design, piston and sleeve construction ie ABC, AAC or Ringed, etc etc.
A competition .21 can have a far greater output than a cheap MT/Truggy RTR .28 engine.
In contrast, I wouldn't really want to put a £500 Circuit engine into an MT.
Oonetz hit the nail on the head - you'll know which one was faster if you were at the track. Bizarrely, it's not always the most potent engine that turns the fastest lap, even with the same driver at the controls - especially with off road racing. Track conditions dictate how much power can be put down, so power delivery invariably makes the difference between fast laps and average laps. Driver confidence is the key. Then of course you've got the fuel efficiency aspect - one less stop during a 30 minute final could make the difference between 1st and 10th place. Reliable engines that hold a tune well are what people really need to enjoy themselves. That and insane power!!
Nitro engines always used to be measured in cubic inches - .20, .21, .40, .60, .90, 1.10 etc.
Traxxas have been giving their engines in CC's, more recently HPI have followed suit.
2.5, 3.3, 3.5, 4.1, 4.6 etc
Initially, I'm quite convinced it was a clever marketing move as PSO mentioned.
Conversion is quite straight forward. There are 2.54 cm in 1". As we are talking about cubic measurements, you have to do every thing to the power of 3.
1.0 Cubic Inch = 2.54 x 2.54 x 2.54 = 16.39cc
.25 Cubic inch = .25 x 16.39 = 4.1
Converting it the other way around is a simple division excercise:
23cc = 23 / 16.39 = 1.40 cui
5cc = 5 / 16.39 = .30 cui
There aint no replacement for displacement......alledgedly!
Besides Turbos, Superchargers, multi valve engine technology, ECU technology that is!!
In the context of nitro engines, we have other factors like intake timings, compression ratio, side or rear exhausts, number of ports, crank, rod and piston design, piston and sleeve construction ie ABC, AAC or Ringed, etc etc.
A competition .21 can have a far greater output than a cheap MT/Truggy RTR .28 engine.
In contrast, I wouldn't really want to put a £500 Circuit engine into an MT.
Oonetz hit the nail on the head - you'll know which one was faster if you were at the track. Bizarrely, it's not always the most potent engine that turns the fastest lap, even with the same driver at the controls - especially with off road racing. Track conditions dictate how much power can be put down, so power delivery invariably makes the difference between fast laps and average laps. Driver confidence is the key. Then of course you've got the fuel efficiency aspect - one less stop during a 30 minute final could make the difference between 1st and 10th place. Reliable engines that hold a tune well are what people really need to enjoy themselves. That and insane power!!
05-08-2006, 06:12 PM
#11
Tech Apprentice
My question is for Horatio...where can we find turbos for our smaller displacement engines? I've heard of prototype superchargers for larger displacement engines...but never turbos. I heard of a few guys working on building one for their trucks...but none of them were ever successfully produced that I know of. BTW, I know all about turbo dynamics and engine responses and required mods to engine characteristics, I turbocharged my Acura Integra,
Last edited by 86Lude20Si; 05-08-2006 at 06:22 PM.
05-09-2006, 08:12 AM
#12
It's an interesting subject! I confess, I don't know very much about Turbo Charged 2 strokes. Most people respond thinking that Turbo Charging a 2 stroke is simply not possible. It's often been the centre of many a heated debate! However, I know that big industrial Diesal Turbo Charged 2 stroke engines are produced, so obviously they can be made to work.
Recently, you may have seen Turbo Charging systems available for our nitro engines that claim to improve power. As they are pulley driven systems, Technically they are Superchargers. They might very well improve power - but I doubt they improve power by more than a tiny percentage, and any power gained would most likely be lost in the pulley system that drives it. Otherwise, we'd be seeing them utilised at big races and this clearly isn't happening. It's still kinda cool though!
What many people seem to forget is this - with a tuned exahust system on our nitro engines, this effectively is a really efficient form of 'Turbo' Charging effect, that takes advantage of the Scavenging phase of the 2 stroke engine cycle and requires no moving parts.
Recently, you may have seen Turbo Charging systems available for our nitro engines that claim to improve power. As they are pulley driven systems, Technically they are Superchargers. They might very well improve power - but I doubt they improve power by more than a tiny percentage, and any power gained would most likely be lost in the pulley system that drives it. Otherwise, we'd be seeing them utilised at big races and this clearly isn't happening. It's still kinda cool though!
What many people seem to forget is this - with a tuned exahust system on our nitro engines, this effectively is a really efficient form of 'Turbo' Charging effect, that takes advantage of the Scavenging phase of the 2 stroke engine cycle and requires no moving parts.
05-09-2006, 08:14 AM
#13
Originally Posted by 86Lude20Si
I turbocharged my Acura Integra,
Do they Turbo Charge 2.0l Zetech engines?
Oh, I guess I'm outta luck then! 
05-09-2006, 08:42 AM
#14
Tech Apprentice
Originally Posted by Horatio
Sounds like a really pimpin' ride.
Do they Turbo Charge 2.0l Zetech engines? Oh, I guess I'm outta luck then!
Do they Turbo Charge 2.0l Zetech engines?
Oh, I guess I'm outta luck then!
05-09-2006, 09:32 AM
#15
Sounds like alot of fun.
I'd often thought about sorting out a nice dual exit stainless pipe for my 2.0 Mondeo (it's a 5 speed Mk1), from the CAT back. Perhaps add a nice induction kit - with a Powertec stainless steel filter. Maybe with just a hint of getting it chipped.
Now I'm being told to add lashings of Turbo flavour too!!
It certainly has the grip now, with 215/40/17's - so perhaps a trip up to 200bhp isn't as impossible as it seems? What do you reckon?
V6 Discs on the rear, to match the Grooved Black Diamonds I've already fitted up front (I've warped so many old stock discs I couldn't afford to fit them any more!! ) and then I'd almost be pimpin' too. I suppose I could just change the lights etc and just pretend it's an exotic far eastern import!
I'd often thought about sorting out a nice dual exit stainless pipe for my 2.0 Mondeo (it's a 5 speed Mk1), from the CAT back. Perhaps add a nice induction kit - with a Powertec stainless steel filter. Maybe with just a hint of getting it chipped.
Now I'm being told to add lashings of Turbo flavour too!!
It certainly has the grip now, with 215/40/17's - so perhaps a trip up to 200bhp isn't as impossible as it seems? What do you reckon?
V6 Discs on the rear, to match the Grooved Black Diamonds I've already fitted up front (I've warped so many old stock discs I couldn't afford to fit them any more!!
) and then I'd almost be pimpin' too. I suppose I could just change the lights etc and just pretend it's an exotic far eastern import!