High speed buggy project...... - Page 4 - RC-Monster Forums

lutach · 04.23.2008, 09:27 PM

Quote:

Originally Posted by jzemaxx

The black TT supra is no longer TT. Its now being converted to a single GT47-88mm turbo. Should put down around 1100rwhp or so.

Anyhow, back to the fun stuff...hehe. I tried fitting 4 lipo batts that I had laying around and 2 of the HV100 turnigy's I had extra. I don't think this is going to work..... So my question is what do you guys think would be the best way to go. Just run a single 1527on 12S or is their a different motor I should try?? I want 100mph out of this big buggy. I've seen 100mph+ RC's but they are all small, lightweight and don't look anything like an RC. Most of them use bodies that look like they came straight from wind tunnel testing and most are 4-5lbs max. That doesn't impress me, but I think small and light sure makes it alot easier to get these things to go fast.

You can try and see if 12S 2200mAh (4 x 6S 2200mAh) in a long style pack will do. The pack inside my truck in the pictures show how a 4400mAh 3S2P long pack looks like. That pack can be 6S1P for 22volts. Some places has good 25C and 30C 2200-2600mAh 6S packs. Thunder Power has the following: TP2600-6SXV, 22.2V, 6-Cell, 410g, 44x39x125 and $179.99 or TP2200-6SXV, 22.2V, 6-Cell, 340g, 51x33x107 and $149.99. You can also use the long type higher mAh packs like the following: http://www.kongpower.com/product_en/...pkind_recno=KP or http://www.airthunder.com/5000mah222...erypack-2.aspx. I know Flight power makes the long type packs as well. With the higher mAh pack all you do is put one on each side of the chassis and make a plug to hook up both controllers to them. The only weak link now will be the moving parts.

jzemaxx · 04.23.2008, 09:30 PM

I'm going to see if I can move some stuff around and fit the parts. If not it maybe just a single 1527.

aqwut · 04.24.2008, 12:15 AM

Quote:

Originally Posted by jzemaxx

I'm going to see if I can move some stuff around and fit the parts. If not it maybe just a single 1527.

that would be your best bet man, then again, it's all about aerodynamics and Power:Weight....

tashpop · 04.24.2008, 01:10 AM

man i'll give you my setup out of my yusa rally in a trade for a turbo set/install on my N/A crossfire. it metered around 6hp.

seriously though, i'm liking this buggy. i seen another one somewhere and i got excited and started searching ebay for a roller. couldn't find a deal so time went by and i forgot about it.

xcntrk · 04.24.2008, 08:17 AM

Quote:

Originally Posted by Arct1k

No - I was thinking what kind of turbo can you get in an Audi TT 3.2...

Linc - We all need someone :)

K04 kit would work. My buddy runs a GIAC reflash with K04's in his TT S4. Very nice setup unless you need to have it $erviced.

jzemaxx · 04.24.2008, 09:35 AM

Quote:

Originally Posted by aqwut

that would be your best bet man, then again, it's all about aerodynamics and Power:Weight....

Are my calculations off?? Or should 12S and a 1527 be around 4300-4500 watts?? The motor will draw 100 amps minimum I would imagine. Doing to math that should be enough to push the buggy at least close to 90mph if not more. Right now I'm running the MMT with only around 3600-3700 watts and its heavier and less aerodynamic, and its not even getting hot at all. So 1hp extra should get me another 10mph or more right off the batt with the right gearing, plus I should be able to gear up more from there. Maybe my thinking is off...

jzemaxx · 04.24.2008, 09:37 AM

Quote:

Originally Posted by tashpop

man i'll give you my setup out of my yusa rally in a trade for a turbo set/install on my N/A crossfire. it metered around 6hp.

seriously though, i'm liking this buggy. i seen another one somewhere and i got excited and started searching ebay for a roller. couldn't find a deal so time went by and i forgot about it.

If you want an XLB buggy, better hurry up and get your hands on one. XTM has discontinued the production of it. Good thing is all the main parts are Mammoth ST parts, so plenty of replacement parts out there.

lutach · 04.24.2008, 09:44 AM

Quote:

Originally Posted by jzemaxx

Are my calculations off?? Or should 12S and a 1527 be around 4300-4500 watts?? The motor will draw 100 amps minimum I would imagine. Doing to math that should be enough to push the buggy at least close to 90mph if not more. Right now I'm running the MMT with only around 3600-3700 watts and its heavier and less aerodynamic, and its not even getting hot at all. So 1hp extra should get me another 10mph or more right off the batt with the right gearing, plus I should be able to gear up more from there. Maybe my thinking is off...

It will come down to gearing too. My BPP with 10S geared the same as 6S with the 1521/1Y at close to it's rpm limit pulled 4760 watts. You might see 100A, 80A or 200A. If you use the 100A 12S controller with the 1527/1D, you might kill your controller. Might not happen on the first run, but it will happen soon. I think that's the reason my HV110 failed, but the Schulze 40.160 is still going as it can deliver that kind of power and more.

jzemaxx · 04.24.2008, 09:56 AM

Quote:

Originally Posted by lutach

It will come down to gearing too. My BPP with 10S geared the same as 6S with the 1521/1Y at close to it's rpm limit pulled 4760 watts. You might see 100A, 80A or 200A. If you use the 100A 12S controller with the 1527/1D, you might kill your controller. Might not happen on the first run, but it will happen soon. I think that's the reason my HV110 failed, but the Schulze 40.160 is still going as it can deliver that kind of power and more.

My 1527 is the 1.5D, which is only 1500 KV, so less then even my 1521 which is 1900 KV. The 1D motors are amp hogs and draw 200A's. I don't care for those motors...

BrianG · 04.24.2008, 10:06 AM

The majority of your HP and torque will be at take-off and possible at the upper end of the speed range where drag is the greatest. Depending on how high you have to gear up, I would expect more current than 100A even on 12s considering the weight of your vehicle. Some of the lighter cars are pulling over 100A. How about using a Castle HV-110? They are actually underrated and should be more like a HV-130. And Castle may be willing to add an extra FET PCB to get it up to something like HV-170 level. Or, their hydro HV-240 would be possible if you replace the cooling tubes with actual heatsinks.

Also, while dual motors increase output significantly, the output probably won't be exactly double because of the slight parameter tolerances; one motor may be spinning slightly lower than the other and/or ESCs may not be outputting the exact same throttle level as the other. I would use one larger motor instead. Weight will be reduced and setup will be simplified. A 1527 1.5d or 1y (kv around 1300) on 12s should be plenty.

Something else you want to look at is if you can get the gearing needed to reach that speed with the spur/pinion, tires, voltage, motor kv, etc you have. Since your vehicle will be so heavy, what about using a two speed? If using a single speed, the motor may have a hard time to pull that weight geared so tall (more of an issue with a single motor). The only thing I'm wondering is the tires breaking loose on shift.

At the start of my project, a couple hi-speed "veterans" chimed in. While their vehicles were small and light, they said aerodynamics plays a VERY big role. The idea is the make the body as aerodynamic as possible (this includes covering turbulent areas like under the car, around suspension components, and around the tires), while providing adequate downforce (but not too much) to keep it planted. Hence, the funny looking body styles. I have a Porsche body I'll be using for playing around, but am planning to make a homemade lexan/plexi body similar to the typical "airplane" looking ones for the high speed runs.

lutach · 04.24.2008, 10:11 AM

Quote:

Originally Posted by jzemaxx

My 1527 is the 1.5D, which is only 1500 KV, so less then even my 1521 which is 1900 KV. The 1D motors are amp hogs and draw 200A's. I don't care for those motors...

The rotor on the 1527 is also longer then the rotor of the 1521. Even if the 1527 has a lower Kv, it will require a little more power to get it moving. My 1521/1Y states a max amps of 75 for 30 sec., but it went all the way to 169A and my truck is lighter then your MMT. Your 1527/1.5D will be up there. I'm guessing over 150A spikes.

jzemaxx · 04.24.2008, 10:21 AM

I will run the 1527 on the HV 110 then. I have it laying on the shelf since I was trying to cure my glitching problems. Apparently the Turnigy did a little better but still not good.

aqwut · 04.24.2008, 11:37 AM

I really can't wait to see the performance of the 1527.... still waiting for the 40.300 by schulze as well.. Lutach.. does ur Jazz have reverse?..

jzemaxx · 04.24.2008, 11:39 AM

The 1527's should start shipping by end of next week.....

lutach · 04.24.2008, 11:57 AM

Quote:

Originally Posted by aqwut

I really can't wait to see the performance of the 1527.... still waiting for the 40.300 by schulze as well.. Lutach.. does ur Jazz have reverse?..

The Jazz 55-10-32 does have 2 car modes. One with forward/reverse and one for forward/brake. If you go with the Power Jazz 63 you will need mechanical brakes. I have a Actronic 120 that has a car mode as well, but it is only forward/reverse and it handles 12S lipos. The only problem with the Actronic 120 is it doesn't seem to work right in car mode. The 40.300 will be huge and if the 40.160 now cost over $700, you know the 40.300 will be about 2 times that. I would just get the SHV 250 from Castle. You know they might even program it for car use. There was a post in rumrunnerracing.com of a guy who had one made, but for industrial use. I can't seem to find that post anymore. Castle has to start doing HV for us car guys and his only competition will be: Schulze and MGM.