cat samich

so i found his tmaxx.15 at a garage sale for 30$ it needs new bumpers/skid plates/front bulkheads. not to mention it has a mixture of both rpm and stock a arms. it has a healthy coat of filth from years of abuse. surprisingly the old .15 still runs! here comes the fun part. whats the best bang for the buck .21 conversion kit? also my last maxx had an ofna .21 the one with the black head and the turbo crank. im not sure what setup i should go with. my last nitro truck was a revo with all rd logics aluminum trim a siro .23. this truck is going to be a pure basher so i would love to hear everyones opinions. i will get some pics up as soon as i can. thanks all

JB COMP

The Ofna 21 (I'm guessing a Hyper) is a pretty weak engine. I have a Hyper 21 8-port, and its fairly weak in the low and mid range, and is okay on the top. Top end is about the only power on my Hyper.

A better engine would be a Sportwerks 26/Mach 427 They're cheap and they have great power for the price. (under $150)

ratpower396

I have a maxx with the xtm conversion & a hpi.25 from a savage & this truck really runs good..Had to change the tranny gears to the supermaxx foc kit after the stockers blew up but after that no problems..

cat samich

yeah it was the hyper 21. and i found it to be pretty hot in that truck. it would pull wheelies effortlessly. as far as all around performance it made it a whole different truck. then again the engine you suggested might make it even more radical. i do think im going to get a spool for the center diff and make this truck a 2 wheel drive 80% on road and 20% offroad. i will look into the conversion kit that was suggested, and also the engine that was suggested. thanks for the help guys. any more thoughts anyone else?

phonedrn8

take some pics before and after so we can see the rebuild

JB COMP

I have a Mach 427 in my CRT, and it will lift the front wheel off the ground a little, its got nice nice low-mid, and good top as well. The SW26 V2 is the same as the 427, but its cheaper at some places. So are parts, I think I saw a Piston and sleeve for the SW 26 go for $20 on ebay.

cat samich

what do u guys think about the dynamite motors? more specifically the Platinum Series .28 SG ? from what i read it makes 3.8hp and they are on ebay for $229. i dunno if i really wana spend that much on a motor for a back yard basher but none the less i want wheelies for days so i guess im gonna need a real power house.

Sugafree

Don't Believe the HP Numbers.....(There BS) as for the Platinum Series .28....Your Better off with the LRP Z.28R Spec 3 (Pretty much the same) Plus it's $60 Cheaper......

dacaur

T-maxx doesn't have a center diff. If you want to make the truck less capable, all you need to do is remove the front driveshafts and gears.....

cat samich

my bad, its been a while since i had a tmaxx, the spool is for the rear or front diffs. and its not that i want to make it "less capable" as you said, its just the fact is that im only going to be bashing on this truck in my front yard. i have grass and the street. so by removing the front driveline i am simply letting all of the power be put to the back wheels. im gonna take a stab in the dark and say that in my head it makes sense that would make the truck pull the front up easier. please correct me if im wrong. also what do u guys think about the trx3.3? i have 3 old trx motors i could use to do the engine swap program with. is that a good route to go or am i going to be disappointed? what does the engine swap program cost these days? like i said its been a long while since i had my last tmaxx.

dacaur

Well, going 2 wheel drive might make it wheely easier simply because there is less weight in the front after removing the driveshafts and gears. Other than that, you will miss 4 wheel drive. Off road (grass) especially, but onroad too. There is a reason that the high end on-road rc cars are all 4 wheel drive. Besides, If you go with the 3.3 it will wheely easily anyway with the short chassis. I have a .21 and an extended chassis in my maxx, and the stock tires dont have enough traction to wheely in the street. All 4 tires spin as I take off, and then spin again when it shifts to second [X(] , which looks cool but makes it kind squirrely The disadvantage to removing the front driveshafts is that with only rear wheel drive, you will accelerate slower, because you dont have the front tires clawing the ground to help you accelerate. It will be a disadvantage especial in the grass or dirt, since you need traction more than you need power once you leave the street. Thinking that using only 2WD will help you accelerate faster isn't weird, its just wrong. My dad used to think the same thing. When he saw an AWD drive car he would say "its just wasting power sending half of it to the front wheels" Then a couple years ago I had a jeep grand cherokee and demonstrated to my dad why 4 wheel drive is better. Dusty road, I put it in 2 wheel drive and slammed the accelerator... instant burnout... sounded cool but the jeep didnt accelerate very fast.... Then I put it in full time 4 wheel drive (all wheel drive) and did the same thing. No wheelspin at all, just push you back in your seat acceleration. made him a believer in all wheel drive for on-road....

I am building a second max now that started as a .15 narrowmax. I plan to do the traxxas engine exchange. The 3.3 is $110 i know for sure because thats the one im going to get, and I think the 2.5 is around $85. What I hear is, that for the price, you cant beat the 3.3. There are better engines, but they will cost 2-3 times as much.....

As for the spool.. I wouldn't put one in either diff if you are going to drive it on the street. In the front diff it will have a HUGE turning radius, and even in the rear it will increase the turning radius.... If you find you have trouble with power unloading to one side or the other, you could get the sealed diffs from a t-maxx 3.3 and drop them in (direct fit) and use oil to make it a limited slip. but just bashing in the street and in the yard, I doubt it will be an issue.

One more thing... I HIGHLY recommend you get some RPM a-arms (get the widemax arms, not the original t-maxx style), not only will they be tougher, but they will increase the width of the truck by an inch, which makes a huge difference in stability... You will need new turnbuckles too.... My plan for the max I'm building is to the the RPM true track conversion for the rear for $40 ($10 more than buying the arms and new turnbuckles) and rpm arms in the front at around $10 a set.... sounds expensive, but you are unlikely to ever break another arm if you go that route. I have a friend that has spent a couple hundred $$ just on a-arms because he keeps buying the traxxas ones... the RPM arms are basically guaranteed not to break.

Sugafree

I'd gladly pay the extra $10 for this Engine Than do that $110 Trade in for a 3.3

fatkidjoey

dude that sportwerks .26 v2 is a BEAST! i run one in my buggy ( mugen ) and love it i have over 5 or so gal threw it and it still has a lot of pinch !

dacaur

.26? That's just crazy talk well sure you could do it, but I think that would be WAY too much power, especially with the stock short chassis and narrow arms. If you like If you upgrade to an extended chassis and widemaxx arms then maybe, but It would still be a beast... and suck fuel much faster than the .20 TRX 3.3... With the 3.3 the maxx is a beast... all the wheelies you could ever want, assuming you have the traction for it

s7jstep1

i run a o.s.18tm in my revo and i love it. unfortunately is discontinued but i hear th .21 size version is pretty good

fatkidjoey

the 3.3 just sucks , thats all there is to it , i had one on my t-maxx , sold that thing so fast and got a os18tm , the 3.3 is knowen for being a crap motor , yea its good for messing around but it wont last long and the power band sucks for the money the .26 v2 is the best deal

cat samich

wow guys thats alot to think about. well to be honest after a trip to the hobby shop last night i was pretty sold on a picco .26 red dot but for the same money it looks like i can get a conversion and a big block. i dont mind spending the money so i think im going to get the wide arms and a extended conversion chassis. i also think im going to stick with the 4x4. as far as motor goes im still not sure but its going to be atleast a .28 i really wish i could get my hands on one of those os .40 4 strokes with the pull start but they dont make them anymore. so i guess my last question is what is the most durable easiest to tune .28 or larger pull start motor? thanks guys for all the advice, i will try to get pics up before i start to work on it this weekend.

dacaur

a .28? wow... That will be a pure beast.... keep in mind you will need to beef up the drivetrain if you want something that big.... the stock stuff wont hold up.... you are talking 4-5 times the power of a trx .15. It going to be pretty hard to keep the front tires on the ground as well.... get a beefy wheely bar...

skyraider71

Drop in a traxxas exchange engine, MIP clutch, Traxxas pipe. Replace any broken parts. Then go
out and have fun!!!!

skyraider71

The O.S. pull start four-stroke only came in .26. It's no longer available.

JB COMP

No, they came in both .40 and .26.

They discontinued the 40, but they did not discontinue the 26 http://www3.towerhobbies.com/cgi-bin...?&I=LXJRW8&P=0

skyraider71

My bust![sm=shades_smile.gif]

cat samich

my local hobby store wants 140 and my 2.5 or 2.5r (they wont even take the old .15 anymore) for a 3.3. to hell with that. i plan to get all the driveline upgrades to. all metal shafts. my goal is to build it strong enough that the only part that will fail is the wheel hub. 90% of this truck is not going to be traxxas when im done

matts6887

Welp, whichever way u decide to go with it, good luck with it man! its pretty cool to hear that even after all the years of abuse and what not, that that old pro .15 still runs. Again good luck with it man!!! [8D]

dacaur

Woa. Dealer cant do that... You should send an email to traxxas... they wouldn't like a distributor ripping people off in their names like that. The LHS isn't losing any money by giving you the exchange. Either they are just trying to make a little extra money on the side, or they arent an official traxxas distributor.. either way traxxas will want to know about it... Try another hobby shop....

I have to be honest, Ive been looking at that .26 linked above... tempting.... Ill have to do some more research before I decide on an engine....