Lipo's shipped and on there way.
 

I finaly broke down and bought some lipos. I also bought the Astro Flight 109. I purchased them from maxamps.com I purchase 2 18.5 4200 mah and the Thunder Power TP-205 Balancer Adapter, whatever that is. Dont know what I am doing yet, so you will here more from me when I get my truck running and ready to install the batt. Mabey I should check for fire insurance on my house and start off by charging them when my wife and the baby arent home. LOL.

why 18.5 volt packs? are you gonna run them in parallel? what motor are you running?

are you going to run them in parrelal or series.

I have a 7xl and will be running them parrallel to have 8400mah.

dang, thats some insane runtime then!

you must be trying for 20 mins:D let me know how that works out

My E-maxx is to fun to only drive for 8 min at a time. I figured this way I can get my money's worth out of it (at least try) I am hoping for 20 min, but I tend to drive it wide open alot.

lol, just make sure not to blow up the packs or there goes ur investment!

you should get more then 20 easy.

You should be able to get 30mins or more! BTW, if you ever plan on getting a balancer, then you will want a different charger. Most balancers won't function properly with the AF 109.

And it will run like a scalded cat.

Well a different charger is almost out of the question. I just bought it on ebay for $101, and what axactly does a balancer do?

I can get 20 min of runtime on my 9l on 13 GP3300 cells in series.

It keeps the cells in a Lipo pack at the same voltage. It balances the cells during charge. The benefits of balancing are:
-Increased saftey (due to less of a chance of overcharge/overdischarge)
-Increased Life (cells are less damaged due to overcharge/overdischarge)
-Better performance during life (same reason)
-Less expensive in the long run (because of longer battery life)

can you please elaborate? I got two 109d's and four polyquest cells with PCM's..

I bought 2 Thunder Power TP-205 Balancer Adapter. From maxamps.com. How do I hook them up? Or do I, since I have the Astro Flight 109 charger. I bought this charger becuase I thougt it would be the best for 18.5 volts. Most of the other chargers in that price range would not charge that big of a pack.

http://64.233.167.104/search?q=cache:RlLVofDPihIJ:http://www.espritmodel.com/documents...balancer&hl=en

I don't know what
means..

PCM guard is not a balancer. It only cuts the charge if any cell reaches 4.25v (or something like that). Since it won't balance the pack, there can still be overdischarge if the LVC is set.

The Thunder Power balancer adapter should come already wired to the pack. This would allow the use of the TP-205 balancer.
The Astro Flight charger is good for the price (9 cells and 8amps). But, it isn't a CC/CV charger, it is a pulse charger. Most balancers assume that you will be using a CC/CV charger, as the is the standard charge method. They will get confused with the pulsing of the AF109 and could kick in at the wrong time (and potentially make the charge take longer).

So what do u sugest. Also do I need to by a cut off warning? Where do they have them that will work well with my set up

You need a undervoltage cut off, to keep your lipo's in good condition.

Good thing you bought that TP balancer. !

@metalman, you say, that the TP should come already wired to the packs. It is used for charging only, and it has got a plug that connects it to the pack, so i don't really know what you mean with that?

He was talking about his Maxamps battery pack that came with a plug on it that would plug into a TP-205 balancer. He doesn't have the balancer, but the plug he has will work with it. The plug should come already soldered onto the individual cells in the pack. This TP plug can be used for anything since it only acts as an access point to the individual cells.

As far as a LVC device goes, you could try this one:
http://66.241.195.91/lithium/lithium.asp?path1=lithium
There are others out there, but this is the only one that I have bookmarked. :)

You know what this does? is it an immediate cuttoff to the motor or what does it do? it is auto sensing this one right? nice device..

It will pulse the motor (noticably) when the voltage is almost to 3v, and will cut it at 3v (or somewhere very close). It says that it autodetects the number of cells.

Sounds like a winner to me...

It would be nice if you where only able to drive slowly if it dropped bellow the 3.1 volts or so.. It would cut the high current absorbing character from the motor as well.. that would be a nice feature for cars imo.

Once the voltage of the pack climbs back up after it hits LVC, then you could drive the car back slowly. You might hit LVC again, though.