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Replacement motors - Printable Version

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Replacement motors - DO-U-MAXX - 07-13-2004

what motors fit in the 2.5 t-maxx with minimum mods (ie...cutting the shaft, changing the mount and drilling holes..etc) other than the specific "drop-in" motors as I know they fit directly. I noticed an O.S. .21 small block that states it fits in the mounts of standard SB's with 1.9hp and only $100 new. Just checkin out my options as I need a new carb and the 10D carb is like $70 anyways, if a little more money will get a bigger motor, well............... Big Grin .


Replacement motors - DO-U-MAXX - 07-13-2004

alright whats the deal with some of these motors I am looking at. They look like they have the same style shaft as my T but I know they need there own flywheels and clutches. Is it only that it would need to be mounted in a different location than the stock 2.5? In theory any motor, given the physical properties are correct, will fit with some modification to the mounting points on the stock chassis and work.


Replacement motors - SixVi6-Camaro - 07-14-2004

what exact motors are you looking at? Got a link to it? there are soo many motors for maxxes and other monsters out its rediculious.


Replacement motors - DO-U-MAXX - 07-14-2004

I was just being generic in my search. I have found some Novarossi's, and others like Wasp's, OFNA's and Picco's but I was just checking if they needed the .21 conversion or could you just modify the stock chassis to fit the bigger motor mount. I realize that the EZ would no longer work so it does free up some space and weight. I just see that the T-maxx specific motors add a pretty price on the tag and I don't want to convert to the extended chassis at this time, just possibly the motor.


Replacement motors - SixVi6-Camaro - 07-14-2004

ahhh. ok. well if its a big block .21 it will take a lot of modifying to get it to fit a stock chassis. I've seen it done by moving the tranny up one hole on the chassis and doing a lot of modifying. you are looking at around an extra inch of length on a big block vs a smallblock. Most .21 conversiosn chassis are streched by at least 1 1/4" to 1 3/4".

the stock clutch on a maxx will fit right on a big block with the right shimming. the diamaters of the crank snouts are the same just the .21's are longer overall than the 2.5's. Easy fix is just to grind a mm or two off which is common on all big block .21 maxxes.

just for size reference the engine on the far Left is a my old traxxas Pro .15 (same motor mounts and case dimensions as the 2.5) all the others are .21's or larger.
[Image: maxx_65.jpg]
Big difference there ehh?

there are .21's that have the same footprint as the 2.5 and will bolt right in
like this one. that would be your best bet if you want a .21 in your maxx without buying a conversion chassis. I'd just upgrade to a sirio .18. if you go .21 on a maxx it breaks everything. trannys, diffs, the entire driveline is too weak for the torque a .21 puts out. thats the other major problem with .21 maxxes.


Replacement motors - DO-U-MAXX - 07-14-2004

Thanks, thats what I wanted.
what kind of HP and RPM does the wasp .21 put out?


Replacement motors - SixVi6-Camaro - 07-14-2004

well the Ofna version of the Wasp .21 smallblock puts out a claimed 2.38hp. the wasps are the same as the ofna's just with a different heat sink head. they all roll out of the same factory.

http://www.ofna.com/eng-picco-21sm.html


Replacement motors - DO-U-MAXX - 07-14-2004

Thanks six, I actually just got done paying a guy from ebay for a Wasp .21 with pipe and additional cooling head. :p I was kinda hesitant because of the price was rather low and the parts are really new, but I confirmed his email and got a phone # and called the guy twice to talk to him about the parts, so I guess I will see if I get the motor or get screwed, :confused: I hope not the last one. The price was too good to wait until I got a deal on a fantom .18 or sirio .18 drop-ins. I will just have to be carefull Wink , yeah right.
Should be in on friday or saturday I hope and maybe I still can make it out with you guys in elgin and break............................uh, I mean bash with some of you.


Replacement motors - DO-U-MAXX - 07-14-2004

oh yeah, what would be a good gear ratio to start with to get good take off and of course good top speed with that kind of HP and lower RPM's?


Replacement motors - SixVi6-Camaro - 07-14-2004

well stock clutchbell is 20t I'd try a larger clutchbell like 21t (racers edge makes the odd # ones) or 22t and/or a smaller 65 tooth spur gear. This will help gain the top speed that is lost and also save the driveline a little bit and with a .21 in there you will still have more than enough power on the low end to handle that gearing.


Replacement motors - Jack - 07-14-2004

Make sure your slipper is in good condition too!


Replacement motors - DO-U-MAXX - 07-14-2004

yeah I have the RRP dual disk slipper that I will need to loosen up a bit. It is comming with a 21T CB and I have the 72T spur, so I think I may be way too high at that setting yet.


Replacement motors - DO-U-MAXX - 07-14-2004

is the fantom pipe I have going to be good for that motor or it comes with a RD logics pipe and header with it, would that be better?


Replacement motors - SixVi6-Camaro - 07-15-2004

tough call on the pipe. I'd try them both and see which is better. probably because its s .21 it going to like a larger pipe.


Replacement motors - DO-U-MAXX - 07-19-2004

should I get a high end pipe to balance the aggressive torque of this motor with better top end? Which pipe is bigger, fantom or RD?
I notice a lot of people that run the .21SB have the RD pipe on it so they must know something, right?


Replacement motors - DO-U-MAXX - 07-19-2004

I just received this motor today and I completed the installation smoothly into my T-maxx. I could not get any fire until I backed the LSN almost 1/16"+ out past the throttle arm and the HSN around 4+ turns out from stop. I had heat issues almost immediately where I tried to control them with needle adjustments to no availe (sp? its late). I noticed a small 2.5mm hex screw on the block above the carb and I tightened it to stop the carb from rotating. I think I may need to take the carb apart to clean and inspect for debris but does any of this sound off or does anyone have any ideas. Thanks


Replacement motors - DO-U-MAXX - 07-20-2004

nevermind, I cleaned out the carb and this thing rips. i still have minor tweeking to do but its so fast with the 22t CB and 72t spur its hard to handle. Stupid me, I had a loose connection on my battery hook-up and lost it not once but three times on a runaway. The first time I knew what the prob was but I just jammed the wire back in there to help cool the motor off after getting jammed under a bush (260f) and it did it again ................. if thats not bad enough I did it again .................................................................................................................................................. IDIOT does not even come close to how I feel. Luck nothing broke or damaged even though it hit a bush at WOT and stayed that way for 10 seconds until I got it and the third time went straight for a pole and missed ........... but flipped and stuck under a car at 3/4b throttle and burned my arm on the tire by pinching the fuel off at the carb.
SO far an exiting first day with the .21 ;-)
I have a failsafe but the power was cut by the loose wire.