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Pumpin' up a 2.5

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Metalhead Matt

Metalhead Matt

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Northeast Iowa
RC Driving Style
  1. Bashing
Hello there. I'm fairly new to nitro, but not to traxxas. I bought a T Maxx 2.5 on ebay for $170 and it seems to run fine. The guy said it was broke in, but I started from the beginning anyway. It wraps right up on the street, but seems to dog in the grass more then I was expecting. It idles good, Smokes alot all the way through the rpm range and hasn't killed a glow plug yet. Only ran about a quart through it. Also the ez start won't heat the glow plug enough to start it. The ground is clean and tight and the battery takes a good charge. It's only a 1500 shark pack, though. Any comments would be great.:)
 
get a separate glow plug ignitor....

yea they don't like grass. Make sure ya got it tuned good if its smoking all the time lean it a little but watch your temps.
 
Thanks. Gotta get a temp gauge. Separate ignitor does the trick, just wish it would work like it supposed to. No biggy, though. You suggest droppin' a tooth or two on the clutch bell? Or leave the gearing stock and get a resonator pipe? One off a 3.3 perhaps?
 
if you want a torque monster, put on a tuned pipe (resinator, ths) And drop a tooth or two on the clutch bell. And get the biggest spur gear you can find. That will make 'er jam like you wouldn't believe. Of course your top end will suffer. If you drive in grass alot, You might want to get a different set of tires. Maybe some proline mulchers or something a little better for high traction situations.
 
Cool. They're pretty reasonably priced.

Will the 2.5 tranny handle the 3.3? I've seen 3.3 trannys for around $60. Is it a bolt in swap? I'm gettin' awfully excited! Haven't even hit any jumps with it yet!
 
watch the 3.3 trannies close, i saw a new one WITH FOC go for 17+shipping! the other day I woulda bid on it if I woulda been home.

Oh yea and the 2.5 will hold the 3.3 for awhile if ya install the FOC, which is about 10$
 
Metalhead Matt said:
Will the 2.5 tranny handle the 3.3?
Click to expand...



The tranny will easily as long as you have a FOC in it. (forward only conversion) Some people may fight the issue that they wont at all but think of it like this, How many years did people stick Big Blocks on a maxx before they made the grey tranny? It will handle the power. BUT, if you can find a 3.3 tranny and don't mind spending the money by all means get it. It is a direct bolt in with the expectation of the Drive shafts.
 
Try tuning your 2.5. I can't stand all the wheelies mine does, it will handle a 3.3 as far as the tranny goes.
 
hey so i have a 2.5R with a 3.3 engine in it and i would also like to get a 3.3 tranny to help it transfer the power better and faster. first question is that i know its a drop in but will my old stock drive shafts be able to connect with the trannys output?
second question is will the spur gear on the 3.3 tranny mesh with my stock clutch bell that i took from my 2.5R and put on my 3.3? (i know the 2.5 has 72 teeth stock on the spur gear and that the 3.3 has approx 52?) if i were to use the 52 wouldn't that kill my acceleration? third whats the stock # of teeth on the 3.3's clutch bell?
so ya, what would you guys recommend? with the number of teeth on each gear?
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=270329741002
heres one i was looking at on ebay also cause it comes with the break set up still attached.
 
Yea tru dat, I would prob have a 3.3 at 400 if possible if I didn't have a temp probe, cuz I couldn't tell otherwise!
 
You guys never heard of the old spit technique? Never even held a temp gauge and definitely never ruined an engine. If it's smokin', running good and the spit test is in the 3-4 second range, your fine. Nothing against temp gauges, by all means. But I'll worry about getting one for my 1:1 Ranger first!
 
hey stang, i upgraded to the grey tranny and everything bolted up except my front cvd shaft was short. i dont know if the stock plastic one will stretch enough or not.
the spur gear is a different size because the gears inside are different also. when bolted on there was no noticeable change in gearing.
 

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