OK, someone please just make this...

[GTX]

This is my idea. I just thought it up, no real thinking involved.

twin RB Rody .28's
Tall gearing
engines layed on their sides
fuselage (sp?) is the fuel cell
23 inches long
pretty wide too
low profile
front and rear wings
tires inside the body
body 1mm off the ground when the suspension is fully compressed
3 speed center tranny (mad force or custom)
4WD

OK, someone make it I seriously think it would be the fastest nitro out there.

[modellor]

Sounds good but 2WD is better for speed records. Less rotational mass and bind which all holds the car from obtaining top speed.

[Ferrari_Spyder]

someone make this:

24 inch sidecar tires (5)

one solid 2inch axle 3ft long

[]-[]-[]-[]-[]

outer two tires turn with CVD style shafts

multi gyroscopic to keep it upright

600cc sidecar engine driving middle three wheels

[serpent69]

i really don't see a point to the twin .28's. I mean, they're more of an offroad engine, with torque in mind. They have insane power and torque, but i think you could achieve what you're looking for with o, lets say maybe a collari sirio, or a team modded c5, or perhaps the new jp's. They've got like 43000 rpm, at like 2.8 hp. The .28's have got like 3+ but thats basically all for torque, and in this type of comp, i think rpm's are more important than torque, but i like the idea of the laydown engine, and 3 speed. I know that BMT an older 1/8 company made a car with a 3 speed. I'll have to check it out. I wonder if we'll see something new there, perhaps a 4 speed?!?

[nitrosportrules]

go with .12-.15's there faster than a .28

[serpent69]

a good .12 will be faster than a .28 but if you want to go the fastest, since that's what the comp is based on, then you gotta go with a .21 onroad engine, imo. They're almost twice as fast as some .12's and are faster than .15 big blocks. They've got the most rpm's of any rc car engine. So right away, they'd be my first choice in engines. Plus there's a wide array of .21's available, os, picco,sirio,novarossi,novamega,rb,jp,cmb,collari,n ovamax,rex,top, the list goes on...

[DaFF]

Yes, I've a R&B C5 ( mind you the "B" as Buggy version) but it is a VERY fast engine indeed, more than what I can handle anyway !

Even Rody Roem aknowldged that the .21 WS7-2 has more power than the new .28.

But take in mind:

- The .28 is the first R&B pull start, meaning some power robbed
- It has the most torque over any other .21 engine ( even the .21 R&B ) and this instant torque is LOW end torque, which means wheels in the air at every acceleration.
- The .28 is not aggresively ported, i.e. only 5 port if I remember right
- It doesn't have either Turbo plug or anything that will give you more top end power.

Having said that, it is an excellent power beast for MT, the best IMHO.

I would wait for the R&B .28 Race version, this one could make more torque AND more overall power than any race .21 engine.

I know Rody is working on it !

So, for now, twin C5-C ( Circuit version ) RR tuned and with outrageous % of nitro would be the ultimate for a speed run... BTW, does it count if you blow both engines on the finishing line ??? Ha Ha Ha

BTW, the most rpm you can get off a .21 engine is 38 000 rpm UNDER load and that was measured by Rody on a C5 speed run. I don't know of many engine able to do that, even though loads of other manufacturer claims outrageous numbers, it's usually with no load and chance are very high you blow you're engine with no load over 40 000 rpm - watch for conrod flying off the case !!

Mind you, some will argue and might said that with over 50% nitro, some .21 could go higher rpm, but not for very long in my opinion LoL

I almost forgot, ppl thinking .12 or .15 are faster than high end .21 are mistaken, no way on earth it will ever happen - given those engines are geared right -

I've had high end Nova .12 and none of them come even close to the unreal power of a C5, that's DFF guaranteed.

If .12 would have been faster, then ask Steve why he used a Picco R1 in his Super Fast HPI oversized car LoL

DFF

[modellor]

Originally Posted by DaFF

Mind you, some will argue and might said that with over 50% nitro, some .21 could go higher rpm, but not for very long in my opinion LoL

I almost forgot, ppl thinking .12 or .15 are faster than high end .21 are mistaken, no way on earth it will ever happen - given those engines are geared right -

I agree with the Nitro point. I can make more power with 10% than many people are with 25%. Too many factors have to be taken into account and it seems these days that everyone has got it welded into their brain that more Nitro makes more power. Not always the case.

As for .12's. You want to come over the Europe. Even on fast open tracks we are running 7-port outlaw .12's around the pace of fully modded .21 8p Turbos. Again, size means nothing. Power - weight ratio combined with drivetrain efficiency will equal any engines out.

At one track which is big, fast and flowing the 1:8th are doing 18sec laps. We were also doing mid 18's with 200mm with 3-port Turbo EFRA legal engines.

[Spoon37]

Originally Posted by GTX

no real thinking involved.
pretty wide too
body 1mm off the ground when the suspension is fully compressed
4WD

I've cut out the bits that sounded ok - like stated 4wd is a waste of weight for straightline speed.

but you are not really thinking of aerodynamics are you? if the body is only 1mm of the ground even if the track is super smooth/flat what happens when you get loads of downforce pressing on it? which even with fairly minimal wing at 100+mph will be tremnedous pressure, you bodyshell will simply scrape the ground and drag your car to a halt.... even if the suspension is fully compressed, the tyres can and will give enough to make it scrape.....

and the width - ever notice that drag rails and funny cars arent amazingly wide? thats to limit the frontal area of the car for less aerodynamic drag, hepls them to better peirce the air, so ideally you would want a fairly narrow car

as for the RB .28 - dont shoot me down here, but if it is such a torquey motor it can pull very tall gearing right?? wouldnt that help it reach speeds by using gearing that many other motors cant pull?

I agree that twin motors doesnt mean more speed, just better acceleration.....

[crank throw wei]

Originally Posted by Spoon37

I agree that twin motors doesnt mean more speed, just better acceleration.....

Twin motors = twice the torque,which allow stiffer gearing to be used,which means higher top speed.

[DaFF]

Originally Posted by modellor

t seems these days that everyone has got it welded into their brain that more Nitro makes more power. Not always the case

For someone that knows how to tune properly an engine, I can guaranteed that more Nitro = More Power.

More nitro = more available torque, less heat, more rpm it all goes in the right direction BUT it means way less time between rebuilt and high engine internal stress, not to mention higher gas price. That's the reason why we usually go no more than 30% for car.

For a speed run of a few second, who care about rebuilding his whole engine if he gets the speed records anyway ?

Look at boat, they can use more than 50% and make stupid speed run. Mind you, they are water cooled, but I am sure ppl that are serious about this challenge with nitro WILL use very high nitro content. It's a very easy and cheap way to gain power and speed, so I don't see any reason why they would not do it.

Originally Posted by modellor

As for .12's. You want to come over the Europe. Even on fast open tracks we are running 7-port outlaw .12's around the pace of fully modded .21 8p Turbos. Again, size means nothing. Power - weight ratio combined with drivetrain efficiency will equal any engines out.

At one track which is big, fast and flowing the 1:8th are doing 18sec laps. We were also doing mid 18's with 200mm with 3-port Turbo EFRA legal engines.

I am living in Europe LoL

Anyway, yes, you are right small block can be pretty close to big block around a track - Mind you, on a big track with a big straight, they will struggle to follow big blocks.

As a matter of fact, 18 sec is not really a big track by French standard. I am lucky enough to have a track that hosted international and national race. It is a very high quality track, it's like if you are running r/c car on a pool ( ! ), the asphalt is stunning and very very smooth with loads of grip.

The best lap done by a Serpent 950 R ( 1/8 on-road ) with a R&B C5-C is 30 sec ! I am telling you, this is one BIG track, the straight is more than 75 meter ( 250 feet !) long.

The serpent 705/710 and V-One RR ( 1/10 on-road) with R&B V12 just can't follow the 1/8 on the straight. Sure, they keep-up and even can pass 1/8 in the twisties, but get spanked otherwise. They fall-off more than 1.5 sec on a full lap behind the 1/8. Heck, even the 1/5 with 23cc zenoah are pretty close to the 1/10 LoL.

Radar tested speed are in the 70 mph ( 110 kph ) for the best 1/8 and tops out at close to 55 mph ( 90 kph ) for the 1/10 - still pretty impressive for 1/10...) @ the end of the straight.

Been there, saw that, loads of high end Serpent with mostly R&B engine ( living in France and R&B being a French company, I see a lot of R&B of any kind ).

But it is here a speed challenge, who care about handling and taking high speed turn ?


I am again 100% positive than a high end big block is going to reach higher top speed IN A STRAIGHT LINE than any small block.

After all, the best small block are what, 1.5 / 2 hp ? Some big blocks can be close or over 3 hp.

Even though .21 are a bit bigger and heavier, they will have a big advantage in overall power.

You can't bend the law of physics, more overall power = more speed - That is again to say in a straight line and assuming all other parameter ( weight / frontal area / aerodynamics / form factor ../.. ) are roughly equals.

DFF

[modellor]

Originally Posted by DaFF

For someone that knows how to tune properly an engine, I can guaranteed that more Nitro = More Power.

I also know how to tune motors. I do own Palmaris Racing Europe. In the right climate, yes, more nitro does produce more power but when ambient air temperature is around 15degC 10% will be more effective than 25% as it will burn easier maximising the power. People constantly run high levels off nitro and then the next week they are posting on the forums that they lost the race because of a flame out. I wonder why????? When I first started in 200mm (been racing 1:8th for 16yrs including the 24hr at Chateauroux in '94) I couldnt figure out why people were constantly talking about the .12 engines flaming out. I just put it down to the size and running too hot (I never had a .12 flame out yet) but then I started to notice they were running high nitro content in average weather conditions.

I gather you are in France. What track do you race at?

[Spoon37]

Originally Posted by crank throw wei

Twin motors = twice the torque,which allow stiffer gearing to be used,which means higher top speed.

equally true - however some people beleive the myth that 2 motors means 2x power and therefore 2x the speed, which is an over simplification. I have tested this myself - I can stick a 15t in a juggernaut 2 and have it hit 30+mph(not bad for a 5kg monster using a weeny 540 motor) adding another makes no more top speed but it gets there so much faster, and only if it is geared up a fair bit will it make more speed, but not huge amounts unless its a seriously torquey pair of motors.

you need to work out if the extra torque and gearing change is worth the increased weight tho.

Daff has a point tho - as my dad put it once: "a good big'un will always beat a good little'un".

[chevy camaro]

thats true thats like a voltswagon compared to a corvette

[DaFF]

Originally Posted by modellor

What track do you race at?

I live in toulouse, the track I am running at is called " Castel" for "Castelsarazin".

I didn't know you raced in Chateauroux.

Good luck to you.

DFF

[modellor]

Originally Posted by DaFF

I live in toulouse, the track I am running at is called " Castel" for "Castelsarazin".

I didn't know you raced in Chateauroux.

Good luck to you.

DFF

Not familiar with the track in Toulouse. I ran in the 24hr in '94 with the Irish team entry. Some heavy rain fell that year. Made it fun with those old flatpan cars.

Actually putting together a new chassis to enter it again 2006 if I can get hold of an entry form. Was the best event I ever attended.

Good luck to you too. Maybe we will meet up sometime and possibly at the Europeans at Mendip next year if you are attending.

[cliveshell]

Originally Posted by modellor

Not familiar with the track in Toulouse. I ran in the 24hr in '94 with the Irish team entry. Some heavy rain fell that year. Made it fun with those old flatpan cars.

Actually putting together a new chassis to enter it again 2006 if I can get hold of an entry form. Was the best event I ever attended.

Good luck to you too. Maybe we will meet up sometime and possibly at the Europeans at Mendip next year if you are attending.

hi my names clive im from enland, when/ where is this 2006 24hr race? and r you putting a team together? i wouldnt mind attending myself, i build rc cars myself, my current project is a 1/8th all 7075 t6 aluminium racing buggy with maxpower engine. if you have any info about the event or if you are putting a team together id be very intrested so could you email me thanks.

[the-one1]

24hrs with real cars or r/c????? Thats a lonnnnggg time for an r/c.

[DaFF]

It's off-topic, no speed run related, but yes, we do crazy thing over here !

I won't be there though, it's not really my cup of thea to run for 24 hours...

Friend of mine is into that and preparing a prototype for it.

But I heard as well there is enduro type race in America where you run r/c car for extended period of time ?

DFF

[DaFF]

Modelor, FYI the 24 hours for this year is closed, they already have 15 teams and they would only take another team if one of them resign.

It will take place in France on july, it's called "The 24h of KWEB" ( Kyosho website ) and will be in Poissy, close to Paris. Race on 13/14 of July.

My friend is doing it with the same setup as past year, i.e. a Kyosho V-One R with Sirio engine ( only two engine allowed for the race)

DFF

[Stocker452]

laying down the engine will allow for a lower profile body for better aerodynamics and also a lower CG to keep things in control

[Chris LaPanse]

Originally Posted by serpent69

a good .12 will be faster than a .28 but if you want to go the fastest, since that's what the comp is based on, then you gotta go with a .21 onroad engine, imo. They're almost twice as fast as some .12's and are faster than .15 big blocks. They've got the most rpm's of any rc car engine. So right away, they'd be my first choice in engines. Plus there's a wide array of .21's available, os, picco,sirio,novarossi,novamega,rb,jp,cmb,collari,n ovamax,rex,top, the list goes on...

did I hear you correctly? No .21 could come close to the RPM of a .12, but they have much more torque. The reason they go faster is the taller gearing, not higher RPM. It is like comparing a RX-8 to a viper. The RX-8 spins more rpms, but the viper still blows it away. Why? TORQUE. The smaller the engine, the more RPM, but the less torque. Some .12s can spin 45000-50000 rpm, while .21s spin 35000, but the .21 has so much more torque that it still has more power. For this same reason, a .28 will spin even slower, but have more torque, and more overall power. Because of this, the .28 will be slow with the same gearing, but, you could gear it way higher and, therefore, get more speed.

[nitrohead5300]

21's can turn more than 35,000 rpms. Look at the RB Concepts website, they said that a 21 circuit engine can turn 43,000 rpms under load.

[Chris LaPanse]

still not the 50000+ that some .12's can pull. It is simple physics. Larger piston=more mass=more strain on the bearings/crankshaft. Therefore, they have to go slower to compensate. I'm not claiming they make less power, just that they pull lower RPM's.

Side note-In the 100 mph Super Nitro, he used a Novarossi R1. It claims 38000 RPM. In his speed runs, it was pulling about 31000 or 32000 RPM. Basically, under these kind of loads, 35000 RPM is optimistic from a .21 engine.

[crank throw wei]

Originally Posted by Chris LaPanse

Basically, under these kind of loads, 35000 RPM is optimistic from a .21 engine.

Run 2.