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Upgrading to wasp .26, .28 or xtm 24.7

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wannarunem

wannarunem

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I have decided on to upgrade the s-25 mill with either the wasp .26, wasp .28 or the xtm 24.7 pro

Can the stock savage drivetrain handle the extra torque? If not, what all will i need to upgrade so the torque wont tear the stock parts to shreds?


Of the 3 choices.....what mill would u go with??????
 
i would recomend the fantom .27. 2.9 hp and 42,800 rpm. i have 1 and it is great. easy break in and so for it has been easy to tune.
 
of those mills i would choose the xtm 24.7 pro or the picco .26. both engines are proven (I've personally ran both) and either will have as much power as you want. the wasp 28 is new and unproven, (some say the fantom and the wasp 28 are the exact same engines..jsut under different marketing specs and names) and I've -heard- of cases were the fantom 27 runs out of compression after just a couple of gallons, but some also say its been great for them. as for the savage drivetrain the only thing that will definatly have to be done is the 4-spider diff mod. I'm running all stock drivetrain in my savage except for 4-spider mod diff's and so far have no problems.
 
Even the S-25 can shred the diffs so definetely do the 4-spider mod. As for an engine I say XTM 24.7 Pro. I have the original version and it can easily pull wheelies with the RRP 14/52 gear combo, another thing that you might want to upgrade is your spur gear.
 
believe it or not i have the same 49t plastic spur that came out of the box on my savage, and that spur has gone thru 1 gallon of s-25, 2 gallons of xtm 24.7 and almost a gallon of 30% nitro wasp .26 power. i really belive with proper meshing/slipper setting and healthy bell bearings the stock plastic spur is plenty good for any engine. plus..the spur gear is the cheapest and easiest thing to replace...put a steel spur gear in and something else down the drive line will break, and getting to those savage diffs arent exactly a breeze. but to each his own.
 
Mudbug said:
i would recomend the fantom .27. 2.9 hp and 42,800 rpm. i have 1 and it is great. easy break in and so for it has been easy to tune.
Click to expand...
Is yours the '05 edition? I heard that Fantom upgraded their .27 for 2005 so it can use HPI's rotostart backplate and it's also equipped with turbo plug and head button.
 
Fantom with that kind of RPM sounds great. I have read mixed reviews on that engine. I have run the picco .26 and loved it, lots of power and alot of fun in a savage, but it does put extra stress on the drivetrain. you will wear out drive cups and diffs if they are not upgraded. The savage is a tough truck and you should enjoy the upgrade in power, go with a picco .26 over the .28 that is made in asia. The bigger nova and RB .28's are low end power engines and alittle dissapointing on the top end from what I have read. My vote is the wasp or picco .26....good engine.
 
Thanks guys!! i have done the 4 spider mod, but thats the only thing as far as the drivetrain is concerned. Ok.. my next question is ..... I already know the xtm is easy to tune from another thread, but is the picco and wasp easy to tune?

Do any of the 3 require a carb replacement for easier tuning?
 
with my wasp .26, first thing i did was take off the back plate and seal it with sensor safe rtv silicone around the edges. (while you have the backplate off its good time to check jsut incase there are any machine burrs/shavings in the motor if you want) after that i take the carb off, take out the low and high speed needles and took all of the flash off the o-rings, mine had alot on the low and high speed needles. (heard from savage central that alot of others have had same problems with there needle o-rings out of the box). grease up the o-rings, re-install the needles were they belong, then put some more rtv on the carb neck. i did this to mine and my wasp .26 is as easy to tune as any other mill I've ran.

BTW i do this to all the engines i run, before they ever even get installed/broke in.
 
Where can i get some sensor safe rtv silicone ??? i just searched tower and they didnt have anything. I'm leaning toward the wasp.26...but havent excluded the picco or even the xtm 24.7 just yet.

i will pass on the wasp .28 since its just come out.
 
Last edited:
yes i got my hands on a 05 fantom .27. it has a nice smooth powerband. starts up on the third or fourth pull.
 
I have the Wasp .26, ported. It runs great. I still run the original set of dogbones for the wheels. The drivetrain upgrades I did are: 4 spider diff mod, center CVD's, steel brake hub hex. I am still running the original spur gear as well. I use a 16t pinion on the engine. Pulls wheelies easily and runs great.

On the engine itself if you are going to use the rotostart as I did I would recommend changing the shaft with the hex on the outside that it turns. I'm not sure what you call it, but it's the hex on the backplate that the rotostart or pullstart turns. This hex is on a shaft that extends into engine and engages the one way bearing. There are kits available that replace this piece with one that has a longer shaft to extend into the engine. This way you get proper engagement of the one way, and less chance of the one-way going bad, or the shaft getting chewed up. I don't have a link to the item, but my dad found one on ebay I got from him. I have ran almost a gallon through the engine with no one-way problems. Still running the original spur and dogbones with between 2-3 gallons.
 
Mudbug said:
yes i got my hands on a 05 fantom .27. it has a nice smooth powerband. starts up on the third or fourth pull.
Click to expand...
Looks like it's the engine I'm getting when I go racing^^ I have a high power engine already, I want a high rev engine next :D

Torque: 4-spider gear mod = putting 2 more little gears in front/rear differentials.
 
it revs pretty high . don't be fooled by the gasket that come with the backplate and not reseal it. the gasket leaks. awsome power band in it. my buddy has an rb 28 and he thinks it will hang with his
 
BTW the stock savage dogbones are better than the "heavy duty" dogbones from hpi. the heavy duty ones tend to break clean in two, while the stock ones seem to be more resilent. (sp?) I've got the same dog bones out of the box on my savage with 4 gallons almost on them.
 
Mudbug said:
it revs pretty high . don't be fooled by the gasket that come with the backplate and not reseal it. the gasket leaks. awsome power band in it. my buddy has an rb 28 and he thinks it will hang with his
Click to expand...
I see^^ Thanks for the tip.
Do you mean that RB .28 might be faster than the Fantom? Let us know how the Fantom goes in a drag race with your friend's RB .28 :D
 
Doggie said:
Torque: 4-spider gear mod = putting 2 more little gears in front/rear differentials.
Click to expand...


Do u have a pic. 1 or know where i can c 1 ¿?¿?¿?
 
ToRqUe said:
Do u have a pic. 1 or know where i can c 1 ¿?¿?¿?
Click to expand...
https://www.rcnitrotalk.com/forum/showthread.php?t=17342
It's a sticky on top of the forum page...

The question is which brand to use for the gears? We've been getting mixed results... (I use HPI and mine's still ok)
http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXDLD4&P=ML
http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXEPA8&P=7
http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXBZC7&P=7

Oh well, at least choosing the cross pins isn't too hard.
http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXCWG8&P=7
http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXT505&P=ML
 

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