i have a 2.5r from my 4tech and recently just blew up my os .15 motor in my tmaxx. the old traxxas .15 i got with the truck was junk and the os motor was old and beat and finally blew. i wanted to swap in the 2.5r since i already have the engine but am not sure wut changes id exactly need to do to the truck to make it work. any help is greatly appreciated. thank u.
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2.5r into a .15 t-maxx
- Thread starter Jon22188
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- Thread starter
- #3
awesome. i didnt think it needed much. if i was made of money i would have spent the money to go 3.3 and upgrade the drivelike and trans but even the .15 was enough for the way i drive it. the 2.5r will be more than enough. thank u for the tip.
It should be able to hold up. That said, I'd suggest getting the FOC. Takes out some unnecessary rotating mass and gets rid of the bucking that it does off the line:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXCNA8&P=7
Of course, it does remove reverse and all it's components as well.
Also, I'd get some more slipper pegs and fill in all the holes in the spur. Helps with excessive slippage with the power upgrade.
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXCNA8&P=7
Of course, it does remove reverse and all it's components as well.
Also, I'd get some more slipper pegs and fill in all the holes in the spur. Helps with excessive slippage with the power upgrade.
- Thread starter
- #6
i dont use reverse anyways. thank you for the tip. i pulled the old os engine off and the rod was in pieces on TOP of the piston. the throttle got stuck and it took off on me flipped over and was struck revving til it blew. its a blessing in disguise because i really wanted to swap on the 2.5r but didnt feel a reason to tear off a running engine. Also the is it suggested i swap the cooling head off the 2.5r for a different one?
No need for a cooling head swap IMO.
I've never had real heat issues running the 2.5R stock head. The old gray 2.5 head on the other hand was a different story. 
- Thread starter
- #9
i took the 2.5r off of my 4tech last night. to get ready to put it on my t-maxx. the 4tech hasnt run in a while i thought the one way bearing was bad on the ez start but now I'm afraid the r is seized. ill have to take it apart and hope its not damaged. if it is where would i find a new crank, piston, rod, and sleeve for a good price?
Metalhead Matt
RCTalk VIP
You'd be better off to use the trade in program. The parts it takes to rebuild a trx mill adds up close to the cost of a new engine. You could go a bit farther by installing some quality bearings in the new mill as well. Good bearings make for a better, smoother running engine. Just be sure to seal the new engine before installation. Seal whatever engine you go with. This will eliminate air leak problems in the future.
Metalhead Matt
RCTalk VIP
Yeah, probably for the throttle post and pipe hanger.
If you can get the bearings out, then I'd take everything out of the block before hitting with the CC. CC will ruin the o-rings and bearing seals.
If not, then I'd stick with fresh fuel and a toothbrush or DA. I use DA for all of my engine cleaning.
If not, then I'd stick with fresh fuel and a toothbrush or DA. I use DA for all of my engine cleaning.
bottom half? Do you mean the backplate? Or do you mean the sleeve out of the block?
I'm assuming you took out the 4 bolts in the plate itself, not just the starter housing?
Usually a few gentle taps on the flange from the back side cracks it loose. Use something plastic or wooden to not ding it.
Usually a few gentle taps on the flange from the back side cracks it loose. Use something plastic or wooden to not ding it.
- Thread starter
- #20
k i got the plate off the whole inside was gunked and gelled. i poured some nitro fuel and rotated it and it started to turn easier so i submerged the whole block in nitro fuel and ima let it sit over night then tomorrow clean out the inside.