60 mph needs about 2000 watts.

[lipomax]

I've done some experimenting and when I run my Basic XL 2400 using 18/66 gearing (stock tranny and diff) and 22/66 (stock tranny and diff), I keep on getting the same top speed. It seems that this motor could take my emaxx beyond 60.4 mph, but the 8s lipos can't deliver more than 2000 watts so I'm hitting this wall at 60 mph for 8s 3500 Polyquest packs.

So, if you guys wanna hit 60 mph with an emaxx, you need to be able to pump out 2000 watts. In NiMH, that means you need at least 20 good cells pushing 100 amps each.

Too bad my last attempt the thing wiped out and busted off the rear shock tower and shock!!! Good thing chassis didin't break.

[supermaxx4190]

wow, how did you keep that thing strait? how much did it cog off the line?

[RC-Monster Mike]

Thanks for the info, Young! I actually ran my g-maxx on 22.2 volts with the same motor, and 6s Kokam packs. I think the gearing is 15/51. The truck was extremely hard to drive. I am not sure how fast it was going, but it was way too fast for normal driving. i would guess upper 40s to 50 mph. I don't often do these speed runs, but I had someone interested ion the power output of the truck, so I strapped in the voltage and let r rip! I usually run the truck on 18.5 volts, which is still too fast for most tracks.

[Serum]

I can confirm this theory based on a story i read;

In germany they ran a CEN .46, without the .46 on 20 cells and a 2280 and they reached a 101 km/h (63 mph)

A good nimh cell can throw out about 90-100 watts each.

[Dafni]

Oh my goodness....60mph on an EMaxx....:eek: that's insane.

How were your temps on 22/66? What ESC were you useing? How was the cogging at take-off?

These Lehners seem to have some serious power. I'm really considering one.

Originally posted by lipomax
I've done some experimenting and when I run my Basic XL 2400 using 18/66 gearing (stock tranny and diff) and 22/66 (stock tranny and diff), I keep on getting the same top speed. It seems that this motor could take my emaxx beyond 60.4 mph, but the 8s lipos can't deliver more than 2000 watts so I'm hitting this wall at 60 mph for 8s 3500 Polyquest packs.

So, if you guys wanna hit 60 mph with an emaxx, you need to be able to pump out 2000 watts. In NiMH, that means you need at least 20 good cells pushing 100 amps each.

Too bad my last attempt the thing wiped out and busted off the rear shock tower and shock!!! Good thing chassis didin't break.

That's precisely the test I've been looking for.

Yesterday I had a 30120 and Lehner 3100XL in my shopping cart, still deciding on the battery factor though. I think a pair of TP8000-3S4P (11.1v) should do the trick and get my truck to 50mph on the straights.

I calculated (based on weight) that 1.5hp (@50000 rpm) is what I need to do 50mph, w/ the correct gearing (stock, like yours ;)).

You don't happen to have data on current draw, do ya? This would help w/ understanding the runtime potential and average.

Your info seems to indicate that my goal (50mph) is extremely do-able.

[Chase023]

2280, hahah.. one of the bigger Lehner Motors.. Sweet!!

How much do those go for?? I gotta see all possibilities before I go out and buy me a Bolido soon!

Well my E-Maxx run about 40s to 50 maybe, who knows, but its pretty fast.

I need to get me a radar gun.

[Serum]

The bolido looks impressive, no doubt.

But a 2280 can kick out some serious power as well..

I'm sure those 2280's are cheaper and you don't need to wait for them to come out.. (and on 36 cells, it will even make a cathedral fly..) (the new BK controllers can hold up to 36 cells!)

[Chase023]

Actually the Bolido has been out since last November/December. I could of gotten my hands on it back last year but I decided not to.

By the way aren't the 27 series bigger than the 22?

[lipomax]

Amp draws are at about 80-100 amps peak spikes during acceleration. That's not because the motor couldn't take more, but the Lipos can't give more and the controller would probably burn up too if it did. It's the 24.89 controller so running 8s is right at the limit too.

I didn't bother with temps - when doing speed runs, I rarely run 10 minute straight anyways. In either case, nothing ever gets hot. Just warm. Things stay a LOT cooler with this setup than my Basic XL5000 and 12 cells and 15/66 gearing (which only hits about 45 mph).

Cogging? What cogging? Actually, when I do speed runs, I try not to blow up the batteries so I start in first gear, release throttle, switch gear, and slowly gun it in second. The shift from first to second gear occurs at around 45-48 mph!!! A straight start in second gear gives SLIGHT cogging - but I think that has something to do with the ratios being so tall.

6s and 2400 geared 18/66 gives peaks of 50-60 amps in first gear and 60-80 amps in second gear. With 8s, it's about 10-15 amps higher. Note, these are PEAK amp draw. There is definitely some limitations due to the lipos too. Peak amp draw tends to be higher with Kokam 3200s vs. Polyquest 3500 or 3100 packs. I haven't quite measured peak amp draws with their 4400 packs - I don't have enough of those to run in my maxx.

I just ordered the suspension kit and chassis extension from Mike yesterday - but I still haven't found the shocks I wanna run. Mike, you run 4 shocks - what shocks are they? You only got 8 shocks for sale. I only want 4 (to save weight too).

My guess: I think a basic XL series (which is actually about the power of a Lehner "1925" if there was such a thing, could take an ultralight emaxx close to 70 mph with the right tires, more powerful batteries and controller. As a matter of fact, after I busted my maxx, I took it off ebay and now I'm going to see if I can go after Promod's record before I sell it again.

Tires are a serious problem at 60+ mph though. So are batteries.

[RC-Monster Mike]

On my 4 shock trucks, I use the UE racer x shocks. You don't seem to do a lot of hard core bashing/jumping, so you could get away with 4 regular shocks without much trouble. I ran 4 Integy shocks on the g3 suspension for a while, and it worked awesome, but I was bending shock shafts due to the very large jumps my local track sometimes has (not uncommon to get 8-10 feet in the air at times during the year). I agree regarding speed runs - tires are the biggest obstacle(to keep the truck going straight, you need a tire with a low profile and low weight). I think the panther komodos may be the ticket here, though. Batteries are a challenge as well (need enough power!), but I would bet an 8s pack of the Kokam 3200s would approach Barry's record (promod). They can really deliver some power! Of course, a sleek body can make a big difference at these speeds.

[starscream]

Hey Lipomaxx, I was watching your eBay auction and wondered why you pulled it.
Are you interested in unloading your xl1600?

I've got a MBX-5 conversion that could handle it.

[lipomax]

I pulled it out cuz I busted it on my last 57.3 mph run! That's why I had to order all those new parts to fix it up again. I'm going to see how fast I can get it before I attempt to unload it again on ebay. Last run didn't break 60 cuz the batteries were still cold. With lipos, it takes about 5 or 6 long high speed passes to warm up the batteries enough to deliver more amps. So far, my best is 60.5 mph (or was it 60.4??? shoot, I forgot!!!)


In either case, I'm glad the brand new chassis didn't snap or anything... nor the electronics. The XL1600 might be the next motor in my maxx - maybe with 10 or 12s lipo. I think that's the motor I'm going to have to go with in order to get into the mid 60's to 70. I'm not sure if there will be a motor left after running 44.4 volts!!!! I need to find a 40 cell controller (other than that super expensive 40.160 - I'm waiting for CC to come out with their 50 volt model- if they ever make one!)

In order to get to 70, I think I'm going to have around 3000 watts with emaxx sized tires. I believe Promod hit 70 using 1/8 scale rims and tires too. I'm going to try first with stock tires, if that don't work, then I'm going to try to set a "stock tire" record first and then go for his with 1/8 rims and tires.

BTW, I believe the stock tires are almost 7.5 to 8.0 inches during thse speed runs!!!

[luihed]

Originally posted by RC-Monster Mike
Thanks for the info, Young! I actually ran my g-maxx on 22.2 volts with the same motor, and 6s Kokam packs. I think the gearing is 15/51. The truck was extremely hard to drive. I am not sure how fast it was going, but it was way too fast for normal driving. i would guess upper 40s to 50 mph. I don't often do these speed runs, but I had someone interested ion the power output of the truck, so I strapped in the voltage and let r rip! I usually run the truck on 18.5 volts, which is still too fast for most tracks.

Mike, What speed controller were you using running 22.2? also what kind of run time do you think Ill get with a set up like that? Im thinking of going Lipo but still uneasy of teh blowing up stuff lol.....

[luihed]

Lipomaxx, man you must be having a blast doing these speed runs...... I wanna get into this, any pointers?