Foxy

EDIT: Since Neal feels I have little faith (I wonder why...), I'll show some, as long as we stay on the topic of making a Savage faster, as is the thread subject. Knock yourselves out, I'll be watching.

supertib

OMG.... someone is actually spreading real technical knowledge in a thread, nobody is calling anyone names, nobody is bickering like children..... better rush to shut the thread down !!!!! technical topics are not allowed here on RC Universe ! maybe If I added a few swears and some childish comments the moderators may leave this thread going !

llkoolskillet

I thought conversation toned down quite a bit

Neal you say there is no way to make more torque than you already do, well let's just say there is. Look at what my torque motor has achieved. 59 or 60 mph in a savage with a motor designed to move 1/5 scale Baja wheels is pretty impressive. A high rpm motor without enough torque will not push the gearing I have with a .28. Just because a motor modded for higher rpm's like 35k+ does not mean it can push the gearing. Even if you get a super strong motor the tranny is the next hurdle.

savagecommander

If 30 or 35 in-oz is all you need to get down the track youre undergeared. peak HP is as far as your motor should go (ideally)

the OS dyno sheet says 27,500rpm- I'd gear up until the motor stopped at this RPM. Anything else is just for show- and Ive seen a fair share of guys mod out a motor and put it on a short track, geared to 30-35mph and talk about its "top end" -not impressed at all.

to be honest, i found the most advantage in making my savage faster was increasing the diameter of the header pipe.

supertib

Once again there is no reference set for me to judge your engine by............. You say you have huge amounts of torque, which you very well may, however you could just as easily have less then some of the other engines out there.......According to your logic your engine makes more torque and more high end power then anyone Else's does......... you stated earlier that your engine makes power higher in the RPM range then mine does, and now your saying you have more torque then mine does too............... Now considering that you have not really done much testing I find those statements somewhat hard to accept......You very well may be right, but you just as easily could be mistaken.........Until 2 engines are tested and compared back to back in the same conditions with no other variables it is impossible to make any judgements on the performance differences between them.......... Yes you have the fastest single engine Savage.......yes you have made the higher MPH at 29 000 RPM...but you have yet to test any taller gearing, and so far each time you have gone to taller gear the truck has gone faster......there is no evidence to support you have hit the peak and that gearing up further wouldn't produce even more speed.................. Now you also are making assumptions about other engines based off other people's results in doing top speed runs...Unfortunately that logic takes into account none of the variables involved...variables that can dramatically affect the outcome....... We are all running different trucks, in different conditions, using different fuels, different tuned pipes.......Add int he fact that you are the only one who has made any real effort at a top speed Savage.........Its pretty easy to win a game of hockey if the other Team isn't even playing to win........ No offense meant but none of us really put much effort into making a Savage a top Speed machine.......... We stuck a mod 28 in a bone stock Savage XL and did some radar passes..... I think we made about 12 passes in total and melted out 3 trannies.....At the time the gearbox just overheated and the gears melted out....... probably didn't do the top speed any justice either...........

Now you also made the assumption my engines dont make power past 25K.... which is simply incorrect........... my engines all make power well past 25K, some of them actually make useable power to 45K............What I was trying to tell you is that most nitro engines seem to make their highest HP number in the 25 000 RPM range.... some are able to make near peak power well past 25K,but as a trend most of these engines make their highest HP figure right around 25K..... even high strung .21's that rev out to 45K still make peak at 25K...And for top speed runs your likely best to hit your peak MPH right at your engines HP peak....this is where in the RPM range the engine can do the most amount of work....pulling top speed gearing is hard work and to give your engine the most mechanical advantage you want to run at the engines peak.......................

talking about torque...a single speed, 9.5 lb truggy needs a engine with plenty of torque.... without a 2 speed the engine needs to be able to lug the weight of the machine off the bottom with a much taller gearing then the MT has to use...... Its amazing but often times a engine that feels crazy fast in a MT will feel soft and lazy in a Truggy...... Truggies eat up the power like nothing else......

So in the end major props to you for hitting 59 MPH.... I think its fantastic and hope to see you go faster..............Y

savagecommander

most old school guys dont even care about dyno charts- they throw the motor in and thats the dyno- so far it looks like skillets savage is well ahead of anything anyone else has to date. if you want to compare motors put one of yours in one and run it- otherwise any further discussion on your part is hypothetical at best.

llkoolskillet

Neal, one were talkin about a picco 28, and two you still have not explained why on earth you would mod a picco to rev way higher then it's combined average peak rpm of 25k.
Plain and simple my motor does continue to make power above your average dyno number of 25k. The reason I can throw more and more gearing at it and still go faster and faster while maintaining MY average rpm of 28,500 is because i have more torque than a normally modded picco. Based off my calculations, if I was to hit 60 mph it would have been at an rpm of 27,500 with 20/43t gearing. I am not the one who modded my picco, Robin did and he is the only one on earth that knows what he did. All I have been doing is testing out theories that he and I come up with for reaching higher and higher speeds. We have uncovered quite a few amazing things I'm my quest for the fastest savage on earth. Your right not many are open to talk about a top speed savage. But there is actually quite a few that are actively trying right now and very interested in the subject. Where I am no one has really been, thus it's like paving the way to allow others to gain such speed. My goal in starting a thread that is now 20pgs long is to help others achieve insane speeds with there savage. The fastest flux right now uses a 3spd out of an XL, it's claimed top end is 79 mph. The average flux owner gets there flux to speed just above 50 mph without overheating issues and gearig the crap out of it and using belted street tires. Then it would be in the area I'm at. I used to run my mouth all the time saying my ERCM picco is faster than a flux on 6s. Well guess what... It is.
I would absolutely love to see you attempt a run at 60 with a savage. If not have one of your CRE guys do it. The info is out there on how to do it.

supertib

I have explained why we push the RPM's...have explained it multiple times...have also explained why your theory doesn't convince me .....But I dont think you quite understand tho, so we will leave it be for now.......... I will bet right now your engine makes more poop at 25K then it does at 29K... and until you do more thorough testing you will never know one way or the other if I am right or if I am wrong.... your data is incomplete and realistically you are technically unable to even gear your truck to reach peak MPH at 25 K...................so until you have the available gearing needed it is a moot point.....you have reached your peak with the gearing you have available, end of story..

and for myself I have no interest in doing any internet speed war....unless there was some sort of regulations and proper timing equipment I have no interest at all......I could stick a Savage Body on my DM and rip 70 MPH this afternoon....without any clear definition of what a Savage is, there is no point in any shootouts or contests....Myself I ran a stock Savage XL on Terrapins, very much different then what you run

As for shift RPM, we altered ours by changing out the shift spring..by using a stiffer spring we were able to reach a much higher 2-3rd shift RPM.....

and when you say normally modded Picco, who's normal normal Picco ? you definitely shouldn't be referring to anything of mine as you simply cannot know one way or the other how what you run compares to one of mine.........no offense meant to anyone, but you have nothing at all to judge one of mine by, so don't make any blind assumptions nor include me or my work in your stories...

supertib

[youtube]http://video.google.com/videoplay?docid=-1678297284940363929[/youtube]

HPI_Savage_RC

If an engine makes useable power at 40k RPM, it can be geared lower to take advantage of the 20-30k RPM peak and gain a large amount of acceleration while sacrificing some top speed. This is important when the vehicle is intended to be used for bashing/racing, not just top speed runs, and especially critical when the vehicle is rather heavy and has only one gear ratio to work with (buggy/truggy).

For example, your Savage is geared to the moon and does reach a very impressive 59mph, but it takes ages to get there, even with a 3 speed transmission. Your average acceleration values are very low because you are trying to push the truck up to speed using the "weakest" part of the engine's torque curve and the least mechanical advantage possible. On the other hand, if you were to drop one of Neal's strung out race engines into a Savage (Assume for a minute that it can be started without a bump box) and gear it to reach top speed at 35k RPM or so, you may only hit 50mph, but the engine would reach peak output somewhere in the lower mid range and continue to pull strongly all the way into the upper range, resulting in a MUCH faster accelerating and more drivable vehicle.

llkoolskillet

Well I have put up my numbers to compare to yours and my average rpm unload is 3,500 higher than yours regardless of the fact your motor may be able to reach 40k+. However you still want to continue arguing your point of a truggy motor in a savage. But hey when someone wants a modded motor who cares if it makes power lets just let it scream it's face off.

Plain and simple you need torque to push the gearing and HP to carry you across the line. Technically your telling me I don't know how to gear my truck to 25k... Hmm ok I haven't even begun to play with traxxas gearing yet.

My savage also reaches 50mph in the same distance as your 45k truggys. Takes ages huh to reach speed. Kinda funny when its still faster than my 6s flux geared for 75+ mph

I think your right Neal both points have been argued and gotten no where. But if anyone wants pointers on how to go fast in a savage, just ask

HerrSavage

supertib

you have no data on my average RPM.... LOL.... How can you even assume that ? you have no clue what my average RPM is LOL......We have no common testing to compare.

Almost all nitro engines make peak power at 25K....very rarely does one make more power at higher RPM then it does at 25K...even high strung .21's......... you can see the dyno curves for yourself.....

you act like I dont know what torque is...LOL....Of course I know what torque is...look at my dyno curves i posted if you want to see torque my friend..check the OS 28......it eats Picco's for breakfast...single speed truggies require more torque then a 2 speed MT does.... put that Picco in a truggy and see for yourself.....

my truggy reaches 50 MPH in 180 ft.....I think it would go 0-50 MPH and back down to zero in less time than it takes your Savage to reach 50 and it will do it in half the distance.....Savage has zero chance running side by side with the truggy...... And yes the truggy eats the 6S flux alive in a drag race to 50 MPH........truggies accelerate much faster then a MT does.....not even fair or realistic to compare them......truggies are rockets..

in the end major props for you making 59 MPH..I really hope to see you go faster........ however please don't be blowing it out of proportion, you have not engineered the first manned lunar landing here or anything like that, so don't be letting your head swell too far over this one .............

Once again Robin of course did a great job on your engine, but please don't be comparing it to any of mine.... Good or bad you have zero data to compare them one way or the other...

savagecommander

+1

llkoolskillet

haha