Emaxx questions
 

I have decided on a feigao 8xl/mm combo, along with a BEC, single speed conversion, new idler gear, heatsink and fan. I have upgraded the drivetrain to 3.3 specs. I have a few questions:
1) Will the transmission hold up to this motor/esc
2) Can i run this combo on 12 cells?
3) Will i need to upgrade the diffs further if i only run 12 cells at first?
4) Will i have any overheating issues?
5) Are there any more upgrades i should be considering?

I don't care as much about speed as i do about durability and reliability, and i am on a budget. Thanks for any responses.

Welcome to the forums elegal!

1) It should be fine.
2) Yes, it can run 14, if you even want to.
3)Your diffs should be ok for a couple of runs, but the 1/8 scale diffs with the FLM hybrid bulkheads are highly reccomended for BL power.
4)If geared properly, you will have no issues.
5)I think if you will only run 12 cells, a 7xl would be better suited for you.

Welcome to the forums!

To answer your questions:

1: With the mods you did; yes, it will hold up fine.
2: You can run that on 12 cells but you might want 14 cells depending on how fast you want to go.
3: Diffs are a weak point. How long they'll last will depend on how hard you take off.
4: Heat should be fine if you put a small fan on the MM.
5: Dunno. I'll let Maxx guys answer that one.

Sylvester beat me to it! :mad: :)

I had a feeling id have a race to this thread against somebody, lol;)

I plan on upgrading to 4s lipo in the future after seeing what it did to my rc18t on a mamba 6800, so i know i will need to upgrade the diffs when i get these batteries (this is why i want a 8xl instead of a 7xl).
Is there a certain kind of 1/8 diff that will fit in the FLM hybrid bulkheads, or does it only take the HB diffs (I have some old OFNA diffs)?
Also, thanks for your welcomes and responses.

The HB diffs would be ideal. Though, if the OFNA diffs you have are 1/8, they should technically fit.

I'm not sure why you feel like the 7XL isn't an option with a 4S Lipo? It's only a 400mV nominal difference between 12 NiMh cells and 4S Lipo.

I have noticed that there are some people having heat issues with the 7xl, plus a 8xl on 4s lipo will be more than enough power for a regular emaxx, as this is not a race chassis or suspension. Also, i have noticed that the more a truck weighs, the higher the number motor one should get. My truck is not light. I don't see an emaxx being stable at much more than 35mph, so there is no reason for me to make it go any faster than that. Also this is my first stab at a large bl setup, and if i get something too powerful, there would not be much incentive in upgrading later.

One more question: what kind of pinion should i get?

4) also depending on the weight of your truck. Yes everything should be fine if you follow the steps members said above.

Two more questions:
What is the best way to find out if these ofna diffs will fit in the flm hybrid bulks?
What are the best kind of 5mm pinions to get, and should i replace the slipper and spur gear with something stronger? I am assuming something close to the stock gearing is ok to start out with?

There is no really way to test if they fit. But with a minimal amount of dremeling, anythign wil fit. I'd suggest the Hot Bodies diffs just because they drop right in with no modifications.

What are the diffs out of. I might be able to tell you/find out if they fit for you.

That's the problem, i don't know what it is, but the guy that works at the LHS and i think it is an old OFNA buggy. THe date on this thing is approx 1993 give or take 2 years, when i acquired it. Here are some pics of the buggy and the diffs, thanks for any help in identifying it and any info on the diffs. They look pretty substantial to me.

It looks like the Flying Point - Jet Extra that my brother has. I'm not sure how old it is, because he got it second hand about 4 years ago, and I can't find the manual for it.
I took the rolling chassis to my LHS yesterday to see if it was worth converting to brushless (my brother hasn't used it for about 2 years since the crankshaft snapped), and he said (the guy at the LHS) that most of the newer 1/8 diffs are interchangeble, but not all of the older ones are. I guess that doesn't really help you that much though. The version my brother has, has torsen diffs.
I was told it's not really worth converting, it would work, but parts are very hard to get now.
And I don't have any 1/8th diffs to compare to, sorry.

Being that old, I highly doubt that they will fit. I think it is somewhere in the mid '90s. I would guess about a '96 model.

I am going to take the diffs to the LHS and see if the guy will let me take apart one of the diff cases of a 2005/2006 LSP; if these diffs fit in that case, then they would fit in the FLM bulkheads, correct?

if the pinion will mesh good with the diff and everything else fit fine you will be ok.
but i think they didnt invent the so called 7.5 diffs back then. i think that started later.

Looks like an old MP/Dominator diff (actually, it looks like the buggy the dominator and MP were based on!). Those diffs have a relatively large ring gear (similar to a savage) and won't fit a standard hybrid bulk. Funny - some of those diffs only had 2 screws holding them together as well - I think I have a couple of those diffs laying around the shop somewhere.

I will be getting the FLM hybrid bulks with 1/8 diffs in the near future when i upgrade to lipo. Mike was right about the diffs i had, they were too big. Is there a feigao 7xl without a built in heatsink, the only xl i could find on the website without a heat sink was the 8xl. I guess i will be keeping the original spur, what size pinions should i start out with? Pretty sure 15 is stock, how high could i go without damaging the 8xl? Don't want to do more than 40 or so right off the bat.

Stock on a E-Maxx is 18, but you will need 5mm bore pinions anyway, so I would get a Strobe slipper while your at it. Mike should be able to get you a 7XL without the heasink built in, but you will need to get a RC-Monster heatsink/clamp so the endbell doesn't pop off since there only pressed on.

what are the costs/benefits for getting a 8xl with/without a heatsink, do the ones with the built in heat sinks come apart like the ones without? Also, what is the highest pinion # anyone has gone on a 8xl?
Am i going to see a big difference between the 8xl and 7xl on 4S lipo that i couldn't otherwise make equal with a pinion change?

The cost would be about $30 difference. The 8XL with the heatsink built in will not come apart because the endbells are screwed, not pressed on. The speed differences won't be major, but you can gear the 8XL up to almost match the speed of the 7XL. If you plan on running 4S and 4S only, and not going up to 5S, I would probably go with a 7XL.

I thought the front endbell could still pop off the finned motors.

I don't believe so.

http://www.rc-monster.com/forum/showthread.php?t=5786
In the second post Sylvester said the front can pop off. I think some other people have said that in other threads as well, but I'm not sure if it's true or not:032: , I have a smooth can 7XL

Hmm....I suppose so. Never heard of that. I don't doubt it thought...

You can ask MetalMan or Cemetary gates.. it happened to both of them.

the finned motors are better than the smooth feigao motors, but they still can come apart. I had my 9xl pop the front end bell. I JB welded it back on an then it was fine.

What transmission upgrades do i need besides the hardened idler gear for the stock emaxx transmission with the 8xl/mm setup? The single speed conversions are out of stock and i just want to get it running for now. It is something that locks the trans into second gear, but i dont know what it is called or where to get it. Thanks for any help.

If you already have the steel idlers your set!

The steel idler is a very good start, but I also wrecked 2nd gear (bottom one) after a while because of the slop in the dog gear. You can either screw the dog gear to 2nd gear, or get just that part of the single speed conversion. Either way eliminates the slop which is hard on the gears...

What is a good source for that part of the conversion, i cant seem to find it anywhere

Mike might have that part in stock. I'd email him to see if he has the little adaptor part. IIRC, it's like $12-$15 for that part.

If he doesn't have it, you can call Gorillamaxx. The site is down, but maybe the sales dept can place the order...

Thanks, i emailed him. Hopefully the transmission will hold up (with a couple of modifications) until the single speed conversion are available again.
Also, i used your top speed calculator, and with the 8xl, 18/66 gearing, and 12 cells it shows a top speed of 26 mph. Is that really all its gonna do? How high of a pinion number can i safely put on there?
To get 40mph, i would need 14 cells/4s lipo and a 24 tooth pinion.

What you could do is get the Strobe slipper (much better than stock) with the Ofna 51t spur. Then, you could use the a pinion with the same number of teeth, but in mod1 (instead of 32p). It's a good way to lower the gear ratio and improve the slipper clutch at the same time.

Pretty close to that, yes. 12 cells on the 8XL is only 27k rpm. I'd go 14 or even 16 cells to really wake that motor up.

I've never had a stock Maxx, so I don't know which gears are avaliable. Are you running the stock slipper? If so, the slipper pegs are gonna melt with the power. Most people use the 51T mod1 spur, Strobe slipper setup, and mod1 pinions (or a similar beefed up setup) to handle the power.

EDIT: lol, MM beat me to it. Me and my slow typing!

What do i need for the strobe slipper besides the ofna spur and mod1 pinions?

This is the slipper setup. You'll have to use some of the parts from your existing setup. So, all you need to get is the 51T spur, the Strobe, and a mod1 pinion(s) of your choice.

Thanks, i am going to get the strobe and use 51/20 gearing for 37 mph, which is plenty on my maxx

Truthfully, you'd probably be better off adding two cells and going down to 16T pinion. Runtime would be better IMO...