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Old 01-03-2011, 09:20 AM
  #31  
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The kyosho m3 evo drivetrain is about as free rolling as it gets for a 8 scale car out of the box. It feels like it has ceramic bearings. Much better then the mrx4x and 966 drivetrains I had both cars cars. However the mrx4x has a tank almost unbreakable!! And clutch on the 966 seemed to have the most punch. But the kyosho was faster on and off power to me. I just put the mugen clutch on the evo and I love it!!!!!!!
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Old 01-04-2011, 01:37 AM
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Originally Posted by DJ_Shakespear
Hahahhaa, I love it!! But no, seriously, I got a legitimate 9:20
Where do you race ?

Back when I raced Kyosho World cup , the little Kyosho GS15 engines with super conservative port size and timing could be coaxed to just scrape in 9 minutes...Unless of course you are on a very small track and there is no grip and you are just rolling around...


I've yet to see any of today's competitive .12's run any more than about 5:30 An exceptional engine will run 5.45


9:20 ?
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Old 01-04-2011, 04:41 AM
  #33  
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Yep, 9:20, timed from when I got up on the drivers stand to the time it died.

Yes, the track is short has low grip, but with the right setup, which I pretty much have to my driving style anyway, it seems like it has decent grip once you make your clean line after a few laps.

Engine is a Picco .12 JLR Evo3, modified as well, and I do spend time going full throttle, so its not coasting.
I was gobsmacked when I saw it reach the 9 minute mark! I nearly cried in joy about how much I improved this engine!
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Old 01-07-2011, 04:08 AM
  #34  
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Originally Posted by MRX4XXXX
Hmmmm... Somehow I disagree with that. Just built my X5 and indeed it's a nice car but still? All the driveline materials are the same and there is the same amount of belts and pulleys in the same order...

If there is a big difference, I believe it can more easily come from the chassis, suspension and setup and that kind of things than just from the drive-train smoothness.

Just an opinion.

-X-
(-15Celsius and +60cm of snow today here)
i here ya but think of it this way when u entering a turn and your like 20 feet away lets say and u got a car like the 4 that didnt roll as free its like using drag brake so now at the 20 foot mark with a 5 u can let off the gas and carry the same speed and roll around the turn but with a 4 i had to stay on the gas till 5 feet away im just using numbers to make my point but u get the the point that 15 foot diffenance of off gas speed every turn every lap is going to save u a hell of alot of gas.. and yes i beleave what u saying bout setup clutch etc. playing a part as well, but i been making runtime stright out the box with the 5 when the setup was not even half as good as my 4 untill i had time to learn the car and the rear was spinning and sliding everywere and i made run time...
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Old 01-07-2011, 10:02 AM
  #35  
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Originally Posted by ralphierace13
i here ya but think of it this way when u entering a turn and your like 20 feet away lets say and u got a car like the 4 that didnt roll as free its like using drag brake so now at the 20 foot mark with a 5 u can let off the gas and carry the same speed and roll around the turn but with a 4 i had to stay on the gas till 5 feet away im just using numbers to make my point but u get the the point that 15 foot diffenance of off gas speed every turn every lap is going to save u a hell of alot of gas.. and yes i beleave what u saying bout setup clutch etc. playing a part as well, but i been making runtime stright out the box with the 5 when the setup was not even half as good as my 4 untill i had time to learn the car and the rear was spinning and sliding everywere and i made run time...
Have you checked the materials of the suspension, especially the uprights and steering blocks?.
If they are made of a stiffer material then this is the reason why you're experiencing better roll in the new car, combined with the aluminum bulkheads.
When you have relatively soft steering blocks and uprights they will deform during hard cornering or acceleration. This causes the bearings to misalign and thus creating extra drag. This can be partly fixed with fitting a spacer between the two bearings in a steering block/upright. Same thing goes for the bulkheads, the twisting chassis/bulkheads will put extra load on the bearings and thus reducing free roll/corner speed. Most drivers will determine the car's free roll when it is sitting on the bench, but when it's on track and all the forces come into play the situation differs quite a lot.
A good example is the comparison between an NT1 and all the modern aluminum touring cars (Serpent, Capricorn, Shepherd). The NT1 looses quite a lot of speed in high speed corners compared to these new, next gen cars, but on the bench the NT1 driveline feels like on the best. On the other hand the relatively soft plastic of the NT1 makes it a very good car for the average driver.
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Old 01-07-2011, 12:41 PM
  #36  
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Originally Posted by ralphierace13
i here ya but think of it this way when u entering a turn and your like 20 feet away lets say and u got a car like the 4 that didnt roll as free its like using drag brake so now at the 20 foot mark with a 5 u can let off the gas and carry the same speed and roll around the turn but with a 4 i had to stay on the gas till 5 feet away im just using numbers to make my point but u get the the point that 15 foot diffenance of off gas speed every turn every lap is going to save u a hell of alot of gas.. and yes i beleave what u saying bout setup clutch etc. playing a part as well, but i been making runtime stright out the box with the 5 when the setup was not even half as good as my 4 untill i had time to learn the car and the rear was spinning and sliding everywere and i made run time...
...I think it comes from all the little things together. Anyway, this is very good news and I can't wait for the winter to finish to get the first tests with my new car!!!

BTW, if you compare the lap-times to your times with the "4", are they comparable and still saving fuel??

-X-
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Old 01-07-2011, 01:40 PM
  #37  
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Did you check tank capacity? Dollar to donuts the tanks are different size.

Mrx4 tanks are a little undersized around 1-2cc when I tech'd them a while back as are old serpent white tanks. New tanks are oversized from serpent around 2-3cc

Perhaps the new car has tank that is 125cc now.

Being at exactly 125cc is REALLY important when running 5 minutes.

I had old tank in my car and could not make time at last race...beat my head against wall and tech stated it was 2-3cc under after final! My old tank was oversized and I did not want to hassle with getting to 125cc so I just ran tank that I thought was 125cc...my mistake..lesson learned...always check.

Perfect preparation prevents poor performance. Best tuning tool I found to date.
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Old 01-07-2011, 05:25 PM
  #38  
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But it would be better under scrutineering to have a slightly undersized tank, instead of being oversized? Otherwise, an example would be in a power limited race (full scale): The limit is 500 HP. Some just have it set to run at 495 to account for variations that would alter there power (air temp/density) but there is 1 guy tuned at 499 on a hot day. Today, it is cooler and he is actually running 503 HP, so that makes him over the limit, just like having that extra bit of fuel in the tank to extend runtime.
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Old 01-08-2011, 04:02 AM
  #39  
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Originally Posted by MRX4XXXX
...I think it comes from all the little things together. Anyway, this is very good news and I can't wait for the winter to finish to get the first tests with my new car!!!

BTW, if you compare the lap-times to your times with the "4", are they comparable and still saving fuel??

-X-
my lap times are alittle quicker with the 5 my 4 was so dialed so they were bout the same just now i make alot more time im talking somewere in the 20-25 secs more run time which for me is alot!!
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Old 01-08-2011, 04:05 AM
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Originally Posted by J.Gonzalez
Did you check tank capacity? Dollar to donuts the tanks are different size.

Mrx4 tanks are a little undersized around 1-2cc when I tech'd them a while back as are old serpent white tanks. New tanks are oversized from serpent around 2-3cc

Perhaps the new car has tank that is 125cc now.

Being at exactly 125cc is REALLY important when running 5 minutes.

I had old tank in my car and could not make time at last race...beat my head against wall and tech stated it was 2-3cc under after final! My old tank was oversized and I did not want to hassle with getting to 125cc so I just ran tank that I thought was 125cc...my mistake..lesson learned...always check.

Perfect preparation prevents poor performance. Best tuning tool I found to date.
yes the 4 was slightly under but i had made up the differance with extra fuel line so i had it perfect what ever the diff from the 4 to the 5 is, just makes me a happy man now!!
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Old 01-22-2011, 07:50 AM
  #41  
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A good clutch makes a huge difference in run time. Ive made 30 secs less time with a hard clutch.
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Old 01-22-2011, 08:08 AM
  #42  
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clutch and 2 speed is very important.
example, on same track no engine adjustments, just clutch and 2 speed, saturday i struggled to make run time in 18 laps. sunday morning struggled. changed clutch settings a little, and earlier 2 speed engagment, and i made 5 mmins easily enough, but more importantly, for 19 laps this time.
Drag, condition of bearings, and maintaining the correct split, all go towards seconds of runtime. sometimes that is what counts. you miss finninshing a qualifier by 2 or 3 apexes, and these seconds then count.
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Old 02-11-2011, 09:58 AM
  #43  
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One thing to remember Ralphie is the temp/humidity too. I too have struggled with this runtime issue with both .12 and .21's. I noticed on the hot summer days like when you where running your 4 it is harder to make time. I believe you are getting slighty better mileage with you 5 but I think when it gets hotter in the summer time you will be struggling to make time even with your 5. One other thing I found that has saved me fuel is throttle control. On a long straight away I have found there is not a difference in speed if you don't smash the trigger all the way back. Anywhere between 1/4 and 1/2 throttle will give the same speed but less fuel burn.I didn't believe it myself until I tried it.
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Old 11-08-2011, 10:32 AM
  #44  
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bump for a good topic
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Old 11-08-2011, 12:14 PM
  #45  
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Thanks. Almost a year since I wrote that.
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