I think a car like serum's past Serpent onroader would be nice. The only downside is the handling with brushless motors. You might need to use some sticky type liquid on the foam tires to keep the car on a straight line and avoid spinning.
The Kyosho Inferno based on road cars and the Ofna one's are great, but 100+mph would be easier to achieve with the 1/8 on road cars.

The Ofna is an 1/8 on-road car. Besides, this isn't about "easy", but about the challenge and fun (and occasional frustration and not a little swearing). :lol:

The swearing is my favorite part, right after the cogging!

I tried for better balance by placing two battery packs (your old 2s2p milwaukee cells Brian!) on either side of the chassis, one where the radio box was and the other where the fuel tank used to be. This gives me a good side-to-side weight distribution and a little more weight on the rear than on the front. This setup worked best on the tamiya and I hope it will work well on this car too.

Luckily, I've never had a vehicle with cogging, but that's probably because I overengineer stuff. The swearing mainly comes from custom fabbing something only to find that it is 2mm too small! :lol: Going with a pack on each side will severely reduce the amount of room for the other components, so I probably won't go with that for this, plus I want to keep it light.

I have the OFNA roller with a NEU 1512 2.5d on 5s gear'd 18/51 was alot faster than my brothers Inferno GT(supposed to go 50mph).

This car is going to be gear'd 25/51 and settings on the Quark125 toned down. The car has way to much torque.Just a short blast of full throttle balloons the tires so bad they just peel off the rims.
I already have foams for next year,but I think I might be pulling this setup in favor of a NEU 1509 and Quark 80b. on 5s to try to slow this thing down as it's a real handfull.
I'm pretty sure if you want 80mph it is easily doable but good luck keeping it in a straight line.

Well, I'll just have to tighten up the steering and set the radio for exponential steering to maintain fine control. How heavy is it right now with the 1512 and 5s?

You can use the 2200mAh packs from KongPower. I have used them as high as 120A bursts. I have 2 2200mAh packs that had a max burst of 128A and they are lighter then the higher capacity packs.

I'm thinking about setting it up so it can run in two modes:
- High V/low capacity/high C rate cells and gear very high for the top speed runs. I won't need long runtimes for this.
- Lower V/high capacity/fair C rate cells and gear more conservative for playing around in lots/streets and such.

The car ready to go with my PolyQuest 5000mah 5s pack in it weighs in at 8.012lbs.
That doesn't include the body and it's with foams.

That's about what I was figuring. Pretty hefty for a high speed vehicle, but it should help with traction and to keep the front end from flipping.

Speaking of which, did you bias the weight front/back at all? I was thinking of trying to have the weight distribution set to something like 60% front, 40% rear, and then use a rear spoiler to help rear traction...

i have the batt on one side motor and servo on the other with a mount across the rear diff holding the esc.

p.s there is no traction on this lead sled,thats why I'm going such a huge pinion

Hmm, I hope I can find a tire that will give me some sort of traction. Burnouts are cool at first, but tires can get expensive. Whatever ESC I use, I'll probably turn the start power really low to help with that instant torque...

i've yet too run the foams,but i think they'll be less grip on asphalt but at least they'll stay togethet

Seems we all have the same idea. IGT on 6S of TP V2, geared 44/25 thanks to Mike. Powered by a 224 MGM and a Neu 1527 1D. I dont have the motor pictured in this one, but it just dropped right in. Had to make sure the motor wires were at the top though.

So, what motor mount did you use?

I used the Kyosho mount from Mike. I will have you guys know that when I ran the 1527 1D on 6s, it was serious overkill. This chassis did not present enough load to generate any heat in the motor, and contrary to what most may think, and in my experience, I feared hurting the motor that way. I have seen what wide open throttle does to a brushless setup without a load. I now have a 1512 1D on the way for a 4s setup, and will reserve the 1527 for another project. Can anyone say 5th scale brushless.

I think maybe you misread my question: What motor mount did you use? lol, still nice to know about your motor experience though. :smile:

If you underload or unload a motor, the motor usually gets quite warm. If your motor temp was cool, it was probably a good match. I think I'll stick to at least a 1515 since I'll be gearing VERY high. The 1527 is too big IMO.

I think it was just interesting timing. I loaded the page early this morning to post the second listing and didn't get around to it until just a little while ago. When I loaded the posting, I noticed it wasn't the last one anymore, so I edited it. You just posted a reply in the time of my edit. It's all out of sync.

lol, that's funny.

So, it's the Kyosho mount. I assume no modifications were necessary to use it? I like the fact that the mount still allows the use of mechanical brakes...

No modifications that involved anything worth mentioning. As you can see, I opted for the single speed setup. I had a Kanai 2 buggy lying around to rob parts from, so I just used the center diff from it. I replaced the steel 46 tooth gear that was on it with a 44 plastic one I got from Monster as well, and it all just bolted right up. Maybe there was a difference in length for the front center shaft, but as I was getting the CVD's from the K2, so there were no problems. The slots for the screws in the mount had to be dremeled out a bit to accomodate the thicker mounting screws that the 1527 needed, but that was nothing major.

Just curious is the Pro kit or RTR kit?

Hey Guys,

I also have a IGT I am setting up for high speed. All I am missing is the motor. However, I haven't set it up as I am stuck on the brake setup. I wanted to run a Mega Motor setup to maintain the stock radio tray and mech brakes, but there motors are to small in KV for a speed car. So my question is how bad is it on the ESC when you use brakes in a high powered BL setup with a heavy car?? Can I utilize drag brake safely without spiking voltage to the ESC as this would be my next option??

As long as you stay within the voltage and current specs of the ESC, you'll be fine. The ESC will heat up a bit more, but should be fine. You could add a few more low-ESC capacitors to the battery leads of the ESC as close as you can to the ESC. That will help a bit...

The only reason I'm using mech brakes is because I want to use the 2 speed and the centrifugal clutch makes it so I can't use elec brakes. If it wasn't for that, I'd use elec brakes too because it's simpler and lighter (less parts).

Curious: Why can't you use mech brakes?

I plan on using the 2-speed as well. You brought up a good point that the brakes will not work with a 2-speed. The reason why i can't use mech brakes is that I will have to cut out that section of the radio tray for the RCM motor mount. Any other suggestions??:neutral:

You can always remake the servo tray to position the brake servo farther away from the center diff and motor mount. I was going to use a low profile servo and place it above the dirt guard on my hyper7 buggy and just use longer brake linkages.

^ +1 That's what I plan to do with the GTP, except I plan to make all the non-frame parts out of fiberglass for weight, strength, and cost (compared to CF).

Yeah, if you use elec brakes, you are stuck with single speed. For two speed, you NEED mech brakes.

If I had the means that would be an option, but since I don't....... That is why I like the Mega Motor setup.

You can always use mike's motor mount on the front diff bulk and place the motor where the gas tank would be across from the steering servo. The place the batteries on either side at the back, I may do this on the hyper, and not have to mod the servo tray. Not sure what to do, it really depends on battery size.

I am also thinking about that option, except that it looks very tight to fit a motor. Anybody know how long a NEU 1512 or 1515 mtor is??

Never mind, I just figured it out. 1515 is about 68mm

Well, I ordered the Ultra GTP from nitrohouse yesterday. I got the RTR version so it has more "stuff" already on it (body, servos, etc), and I can sell the motor/pipe to recover some of the cost. Anyone wtb a .28 engine with pipe? :wink:

Plus, the listing says it comes with the two speed option (normally ~$100 by itself). No other place lists it as coming with the 2 speed, so I dunno if that was just a misprint - I hope not.

When it arrives, I'm gonna start making the fiberglass brake servo mount/ESC mounting area to give me more room for the motor. I'm gonna hold off on making the battery tray until I figure out exactly which 6s lipo pack I want to use.

Pictures are sure to follow...

Yay, the car came in! Despite Ofna's site saying it only comes with the single speed tranny, it actually does come with the two speed. :smile: The slicks will have to be replaced with foams or something as I can tell they're gonna balloon like crazy. Quality is really nice at first glance.

It's gonna be a huge vehicle though! The chassis is normal size, but there is a lot of space in the front and rear ends of the shell. I'll be able to make a little shelf in those areas to add weight as needed for traction and to help compensate for weight distribution somewhat.

The first thing I'm gonna do is make a new brake servo plate. The existing one leaves no room for the motor. So, I'll fab up a fiberglass sheet and cut out a new plate. Don't know yet if I want to just push the servo out to the side more or re-orient the servo so I have room to use a motor adjustment tool.

The receiver box acts like part of the rear bulk support, so I'm gonna have to fab up a new system for that since it's coming out. I'll probably use aluminum for strength. Fiberglass is strong, but flexes too much.

There will be plenty of room for lipos. I measured roughly 210mm long X 60mm wide X whatever mm tall, and those are conservative measurements.

I won't be able to hit the speeds I want with the stock spur clutchbell options. So, I'll have to mix and match the spur gears as needed. Because the spurs are specific to 1st and 2nd speeds, these are my options:
1st gear: 49T and 47T
2nd gear: 45T and 44T
Also, I need to find spur/pinion combos that will maintain the proper mesh for both first and second speeds. So, I was thinking of using the 49T spur for first, and the 44T spur for second. If I use a 20T pinion for first and a 25T pinion for second, I can attain theoretical speeds of 93mph and 130mph respectively. A little short of what I was hoping for, but should still be fun!

Sorry, no pictures yet. The camera is currently unavailable.

u should enter it in the Radio Controlled Car Action's Second Annual Fastest RC Car Competition.
check out the vid, its nic case with his brushless tc3 winning. 134.4 mph.
http://youtube.com/watch?v=yI5xLNeNDO8

Not sure if I can get it that high. If I can get a 26T pinion made and use Mike's two speed pinion adaptor thingy, I should theoretically be able to hit 126mph in 2nd (1st up to ~95mph). But, I'm sure there will be tons of air resistance and friction at that speed (if the mechanicals hold up). I might use 10s instead for some really high power output because I think I'll need it! And I'm gonna need some serious front downforce. I don't want to think about what would happen if it took off at that speed!

I noticed that the brake on the GTP doesn't have return springs, so I just added those. I also lengthened the brake actuator arm for more servo range of motion and added a spring to the linkage so I have a little more braking control.

Stick some RCM stickers on the shell, that should add at least another 10-15mph, easily.

I believe that if you would put a better rear spoiler you would be ok. That and/or a rear diffuser. That car is too heavy to lift off at those speeds.

What about a front wing too, like some buggies have- that would keep the front glued to the road.

It wouldn't need one if it's the porsche body. It' has a front lip allready.

I use a Mclaren GTR body and it is still loose and all over the place at half the speed your talkin about

On my 10th scale high speed project I tried all kinds of bodies. I can safely say that supra, saleen s7, firebird, focus, nsx, and most other kinds of street car bodies are not good over 45mph. My car was very light, and those bodies had hardly any front downforce, even lowered till they touched the ground. I could get up to around 40 and the front would just get light and I would loose it. I finally settled on a lola 200mm nitro body, with the wheel wells not cut out. It had enough downforce that a windy day would cut the top speed down by 5 or 10 mph! Also cause the chassis to scrape the ground, shock limiters are a must! Plenty of traction at 75mph. I could drift it with complete control at 50mph too. excelllent body for straight line speed. I also made some side body posts to keep the flex to a minimun. Only issue was the lack of air low unpder the body. I put a fan on the mm and it was fine.