CRT.5 newb questions
 

So, as some may have noticed from my signature, I have started a CRT.5 project. What is different about this project though, is that I will retain the stock chassis unlike most who upgrade to an Ofna, RCM or similar extended chassis. The reason why I will keep the stock chassis is so that I will have a variety of different sized rc's to choose from when I drive my rc cars. Because the truck will be about an 85% basher and 15% track car, I need a set up specifically for this. So now on to the newb questions: :mdr:

1) Is there a smaller spur gear available such as a 44t?

2) What is a good weight oil to put in all the diffs (F/C/R) to get maximum performance on all types of surfaces (asphalt, sand, gravel, grass, etc.)?

3) I have 50 weight shock oil in the front and back at the moment, but it seems way too soft in the front. Should I move to 70 weight oil (only weight oil I own above 50) or is that too thick?

4) How does this set up sound...? Mamba Max ESC (already own), UBEC (already own), Lehner XL2400 motor (already own), Hitec HS-5245MG servo , Max Amps 4s2p 5000mAH pack

I'll probably end up with more questions, but thats all for now. I'll post some pictures of the progress, as soon as I get a chance. :smile:

Maxamps have a 4s2p 5000 pack? They have 2500 cells?

That battery may be too heavy, but what is the dimension and weight?

That thing will be fast with the 2400 and 4s, a beast!

I did a stock chassis .5 a while ago, heres a few pics of how I did it:

http://i206.photobucket.com/albums/b...p/DSCF1540.jpg
http://i206.photobucket.com/albums/b...p/DSCF1541.jpg

Nice looking CRT.5 you had linc. :smile: Here is the Max Amps 5000 pack:
http://www.maxamps.com/Lipo-5000-148-Pack.htm
Although I think I was mistaken by saying it was 2p, as I also don't see any 2500mAH packs. I just assumed it was 2p since it didn't say anything about it.

As for the weight, I was also worried about that. But I still need sufficient run time, and need a 4s lipo to reach 40mph... This pack is much better in terms of weight, but the mAH is a little on the low side... Any other recommendations on batteries? Most of the high end packs (Flight power, Trakpower, Neu, etc.) are way too long.

4s@5Ah should give you tons of runtime and/or major power! The 2400 motor should be great on something this small. I get about 30 minutes with 2s 5Ah on a MM 4600 system geared 46/12. Granted, top speed isn't 40 mph, more like 25ish, but fine for my uses. 44/17 gearing should get you in the 40mph ballpark with your motor on 4s, and since you are using HV to get the power, runtime should be great as well, even if you do step down in capacity to reduce weight.

Mine, with stock chassis but home-made tray, mount, etc:

http://scriptasylum.com/bl_conversio...es/crtp5_2.jpg

http://scriptasylum.com/bl_conversio...es/crtp5_4.jpg

jnev,

I agree w/ you on keeping the stock chassis so you have different sizes. If I wanted a 1/10 I would have built a 1/10. :tongue:

I agree with everyone else that it will be a little fat on 4s 5000mah. Thats a pack that most run in a 1/89 buggy.

I am running 3s 3300mah and 3700mah packs and get around 20-25min runtime with them using a Hacker 8L and geared for around 45mph. I could probably get more runtime if i tamed the gearing down a bit, but I tend to be a bit of a speed freak. When Im running it, its usually with 1/8 buggies so I cant have them be faster than me. :mdr:

Mine looks very similar to most others heres a couple pictures.

Instead of going with 1 5000mah pack I would almost think you could find 2 3000mah or so packs and then have 2 to switch back and forth. 1 charging and 1 running. On 4s 3000mah you should get some decent run time I would think.

http://i66.photobucket.com/albums/h2...z/CIMG2370.jpg
http://i66.photobucket.com/albums/h2...z/CIMG2367.jpg
http://i66.photobucket.com/albums/h2...z/CIMG2368.jpg

The wing is now black and I use an UBEC for 3s to help with temps...

<div style="width:800px; text-align: center;"><embed type="application/x-shockwave-flash" wmode="transparent" src="http://w168.photobucket.com/pbwidget.swf?pbwurl=http://w168.photobucket.com/albums/u180/Arct1k/1dd1c2ea.pbw" height="240" width="800"><a href="http://i168.photobucket.com/redirect/album?action=slideshow&landing=/slideshows&type=4" target="_blank"><img src="http://pic.photobucket.com/slideshows/btn.gif" style="float:left;border-width: 0;" ></a><a href="http://s168.photobucket.com/albums/u180/Arct1k/?action=view&current=1dd1c2ea.pbw" target="_blank"><img src="http://pic.photobucket.com/slideshows/btn_viewallimages.gif" style="float:left;border-width: 0;" ></a></div>

I've been looking for a 1/89 buggy!

Although I think it might get lost in the carpet or float away in a strong breeze.

:lol:

Thanks for all the recommendations guys. I really appreciate it.

BrianG - You mentioned the gearing 44/17...? Where can I get a 44t spur?

jhautz - About the 4s 3000mAH battery, I haven't heard great things about the 6000mAH packs. So would it still be all right to run it? It won't heat up too much under heavy driving? Now I have the option of 1 4s 4000mAH pack ($150) or 2 4s 3000mAH packs ($220 for both)....

What weight oil are you all running in the diffs? I will be driving on a variety of surfaces (asphalt, pavement, sand, gravel, grass, etc.) and would rather not change the oil every time I drive.

Edit: Just noticed the tires you're running jhautz. Are those the stock rims with the Traxxas Anaconda tires? I was looking to pick up a set of street treads. :yes: Do they fit perfectly?

I use the traxxas 2.8" rims with the anaconda's - they work great for the street.

Will the Anacondas work with the stock rims though? Because The kit came with a free set of Pro-Line rims, so I might as well use them. I think the Traxxas rims may be a little too big for the stock chassis...

The traxxas anaconda tires for the bandit fit the stock .5 wheels well, just make sure you order the rear tires, as the fronts are really skinny!

Stay away from maxamps, try one of these packs if you want 4s:

Flightpower 4270 4s

This pack will give you better performance and runtime than the maxamps 4000 4s pack. And it will most likely outperform the maxamps 5000 4s pack, and it will be lighter.

Thanks for the info on the tires linc. I'll try to make it to the LHS this evening. :smile:

I also would ideally want to stay from Max Amps packs, because I haven't seen the performance I am looking for from my 1 and only Max Amps pack (2s5p 5500mAH saddle pack for my RC10GT).

The only thing I'm worried about on the Flightpower packs are the length of them. If I measured correctly, the longest pack I can fit is 142mm on the current battery tray. Of course I could always modify it to fit a larger pack, but I want to keep the current battery holder as it is, if at all possible.

I found this pack, which really interests me right now:
http://www3.towerhobbies.com/cgi-bin...?&I=LXRVU1&P=7
It is only 30 grams more than the one Linc linked to, but 30 grams less than the Max Amps 4s 5000mAH, higher mAH and 139mm long. The downfall is that it is $45 more than the other Flightpower... The Max Amps 4000mAH 4s pack is also 25 grams lighter than the 4270mAH Flightpower pack...

I want to get a flightpower pack that is 4s, and no more than 142mm long. So if you see one, let me know. :yes:

What tray does it have in it right now? An emaxx tray?

Right now its the Smoky Racing tray, just because I got it for free.
http://i199.photobucket.com/albums/a...n/DSC02101.jpg

What a coincidence, me too!:lol: