What the ... am I doing wrong?!

[olds97_lss]

I didn't care for the 3.3 I put in my revo either. I bought it NIB at my LHS a few years ago and lived with it in the revo for 3-4 gallons or so, but it was never a "strong" engine. I ran it geared down quite a bit from stock and had a THS torque pipe on it. It did ok, but the only time the front end would come up was either by hitting a bump or a slap wheelie off a jump.

Before I put the 21TM in it, I tried an old tired 18TM and it had more pep than the 3.3 did with the exact same setup. The 21TM isn't a wheelie monster though either still. It's better and wheelies easy in the grass, but on pavement, I really have to hammer it to get the front up. Usually it just takes off really fast. Many years ago when I had my first revo and the 18TM was new, it was a 2.5 chassis revo and it wheelied pretty easily on any surface. That extra inch really tamed down the 18TM. So, I guess if your hunting for wheelies, try getting a shorter chassis. They don't cost much.

My LRP28 revo however is like driving a scalded cat. 2nd gear wheelies aren't uncommon with that thing.

 

[Rooky78]

I'd love to get an LRP in a Revo... but the mounts are getting scarce. I'm not thinking the Traxxas Big Block setup will work.

 

[Raging Revo]

olds97, what engine mount did you use?

 

[olds97_lss]

olds97, what engine mount did you use?

New era and a custom one made by @Racer 1966 on here that made a few. He used mine as a template and gave me his first prototype as a thanks for letting him borrow the mount for a few months.
https://www.rcnitrotalk.com/forum/threads/new-revo-big-block-mount-in-town.105090/

You have to go here for images since my originals don't exist anymore and I had to find a new place to store them: https://www.rcnitrotalk.com/forum/threads/new-revo-big-block-mount-in-town.105090/#post-1100724

On mine, the trans is moved forward about 1/4" so I could fit 1/8th scale flywheel/clutch/bell on it. 1/10ths clutch on a big block just doesn't work well. I'm running an HPI savage alloy shoe set as well. My trans is geared funny since it's running the slayer output gears. I didn't know they were different, but that revo started life as a slayer. Was always wondering how guys were running the gearing they had with their BB revo's. Mine seemed geared so low comparatively. Then when I was tearing the trans down to fix a sheared output shaft... or two speed shaft, I realized the output gears were different than my other revo. Anyway, I digress.

I currently have 2 revos... only using one of the mounts, but odds are I'll use the other one at some point.

You know, looking at that traxxas BB mount... I'm wondering how stupid it would be to try and make some stand offs to stack on it to raise the engine up like the NE mount. A couple blocks of aluminum and long bolts through the engine flange... isn't like you would raise it more than 3/4" or so. Guessing things wouldn't line up right though for the spur/bell mesh.

 

[DavidBasher]

First I wouldn't worry about temps they mean nothing nothing at all. If your engine is well lubricated and it's doing what you say it is it doesn't matter if it's 800° or 50°. Temp guns are in accurate as hell anyways.

Looks like you're running in circles here overthinking this way too much in my humble opinion. My my suspicion is either the engine simply is not tuned or there's an issue with your clutch slipping. But this really can't be diagnosed without seeing and hearing it. Post up a quick video I'm sure you'll get plenty of feedback. A picture is worth 1 million words in this scenario don't you think? Otherwise were just guessing on your opinion and often we look at something so closely for so long our view becomes distorted. That's been my experience anyway.
To that end I have yet to see any vehicle go from pig to beast simply by going taller or smaller with the gear ratios (within standard parameters). It's almost always simply just not tuned well but we can't rule that out without hearing it.
Post up that vid and you'll get a definitive diagnosis I'm sure.

 

[Rolex]

First I wouldn't worry about temps they mean nothing nothing at all.
it doesn't matter if it's 800° or 50°.

Seriously? Don't even THINK about posting something like that and not being challenged!
If that's the info you give, I wouldn't believe ANYTHING you say.

 

[Raging Revo]

IMO, which has no weight; HEAT/TEMP'S are very important

 

[hamz9561]

I know from my experience, the Traxxas 3.3 tends to like to run a bit hotter. My Picco ran best at about 215-230º F. The Traxxas preferred 270-285º F. Go figure.

I also have to disagree with inaccuracy in temp gauges, @DavidBasher. I have had a couple of hand held types (infrared) and they been with 1-2% of one that was calibrated by a test lab.

 

[Rooky78]

Mine is good and consistent with higher priced units. I don't have the advantage of scientifical type stuff though.

 

[Raging Revo]

I also have to disagree with inaccuracy in temp gauges, @DavidBasher. I have had a couple of hand held types (infrared) and they been with 1-2% of one that was calibrated by a test lab.

I do as well but no sense in fueling the fire, my temp gun is quite accurate and I'm happy with it, it sure bets guessing.

 

[hamz9561]

Mine is good and consistent with higher priced units. I don't have the advantage of scientifical type stuff though.

I'm lucky enough to be friends with the guy who used to be my boss when I built avionics. He'll occasionally let me test my equipment against the stuff they have calibrated semi-annually if I'm in the neighborhood and they're not using it or really busy...

 

[Rolex]

Apparently, according to @DavidBasher there's no need to calibrate or even carry a temp gauge. He can make it run from 50 degrees to 800. Amazing!

 

[Alexander_0_1]

I haven't played with a nitro for more than a year, but just to soothe my curiosity what fuel are you using. Maybe you fuel has too much oil content, and running it too rich is causing the un-burnt oil to heat up an congeal causing the engine to work harder per stroke, perhaps too hard for a small block?....but then again I'm starting to need a refresher course in nitro, the last one I played with was "loner" with a burnt piston and sleeve, l just play with it till it would heat up too much that it would flame out, then I'd let it cool for 30mins, and go again.

 

[Rooky78]

I'm running Byrons 20/12.

 

[Certified Mike]

My revo RIPS wheelies, all the time... Right out of the box it did. Honestly, I didn't read thru all the posts on here. I know that there are wide and close ratio trans gears avail for the truck... Did you replace the gears at all? Also, if the shift point from 1 to 2 hear is not set right, it is entirely possible me you are starting in 2nd gear. If that's the case, it's gonna be a dog off the line and eventually, it will get to a strong high speed. That would certainly overwork your engine. Takes a lot of juice to get those big fat tires rollin, causing a lot of heat. Just some thoughts... Curious to know what you find tho so let us know.

I have a 3.3 stock motor in mine. It pulls wheelies all the time ( so long as I have traction). My gears all all stock. I don't know why so many ppl are saying it doesn't wheelie. Maybe I'm just lucky and got a real snotty motor? Anyways, I will leave you with this simple thought. Traxxas put wheelie bars on these truck... Not just for looks. Needed them so much so that they offer a hopped up version of wheelie bars avail for it as well.

 

[hamz9561]

I actually installed the center diff in mine to keep the wheels on the ground when it had the original 3.3. No with the Picco, it's mandatory.

 

[Certified Mike]

I actually installed the center diff in mine to keep the wheels on the ground when it had the original 3.3. No with the Picco, it's mandatory.

I was starting to wonder if it was a glitch in my memory! Like maybe I was the one doing wheelies! Bruuuuuum bruuuuuum!!!!

 

[Rooky78]

I really think I just have a junk motor. 15/38, wide ratio trans, and it most definitely shifts.

 

[olds97_lss]

No wheelies here either with my 3.3 and 15/40 gearing. Wondering if the wheelie happy revo guys are running the 2.5 chassis that is shorter. I know my 18TM was a wheelie fiend in my old revo that was a 2.5 chassis, but once I got the 3.3 chassis, the wheelies dropped off considerably.

 

[Certified Mike]

I've only owned this one, bought new, 3.3 motor and chassis and it rips wheelies without a flinch. (til I fried the trans anyway).
The idea behind my question about the original chassis was based on that anyways... Like are there differences in the difs? This may still apply either way... If the difs are built or set up to run a 2.5 efficiently...??? or if there is something wrong with the difs and the lower powered 2.5 didn't show the problem until the 3.3 really started spinning things and made it apparent...??? Not having the truck in hand to look at and diagnose, something like this is very difficult to figure out.
Please keep us informed as far as what you have and have not tested and checked etc, results??? I'm sure there are lots of us who would LOVE to hear the solution to this issue!!!