showmerc.com
Traxxas 2.5 T-Maxx Review
After seeing many videos on the internet i decided to get one of the new 2.5 maxx for all the improvements.
New wider suspension arms with adjustable castor and three shock positions on the shock tower and 4 positions on the lower arm. The new suspension offers more shock mounting options and although the arms and towers have a teeny bit more flex than the proline it offers greater tuning than the proline suspension. New and thicker chassis,3.0 mm instead of 2.5 mm. And of course the new 2.5 cc's (.15 cu in) rear exhaust small block. This engine is much more than a vast improvement over the pro 15 engine and it more than holds its own against the high end small blocks and it can challenge some of the weaker 21 engines installed in T-Maxxes.
New wider suspension arms with adjustable castor and three shock positions on the shock tower and 4 positions on the lower arm. The new suspension offers more shock mounting options and although the arms and towers have a teeny bit more flex than the proline it offers greater tuning than the proline suspension. New and thicker chassis,3.0 mm instead of 2.5 mm. And of course the new 2.5 cc's (.15 cu in) rear exhaust small block. This engine is much more than a vast improvement over the pro 15 engine and it more than holds its own against the high end small blocks and it can challenge some of the weaker 21 engines installed in T-Maxxes.
The new engine features a long and very beefy connecting rod and a offset wrist pin hole in the piston, this increases torque and prolongs piston and sleeve life and reduces friction from side loading. A new composite slide valve carb with a molded in spray bar, an all new easy start and a sealed one way bearing now called a roller clutch by Traxxas. After almost one gallon of fuel this roller clutch has yet to slip. The engine has a square bore and stroke that gives a very wide and usable power band. This practice has been used for years by leading 2 cycle motocross engine manufacturers. A very large air filter is installed as well as a very effective composite tuned pipe, installing any current pipe or air filter may actually hurt performance.
Time will tell if this is true or not but as is has plenty of power and enough to even get a .21 Maxx veteran into trouble if the power it has is not respected. This engine has a unique break in and must be followed exactly to insure great performance. The excellent instruction manual is a must read for beginner or veteran alike. Inside the box you will find the maxx of course, tool kit with extra shock oil and air filter oil, the manual, and the new easy start control box. this new easy start has a built in diagnostic feature with 2 green led's and a feature to protect the ez-start motor and gearbox from overload. When the engine floods and the motor stops turning you can actually hear and feel the protection circuit in the easy start box work with an audible click. Removing the glow plug and clearing the engine out will get you going again.
I installed the following hop-ups to reduce weight and improve reliability: MIP center drives, Traxxas forward only conversion, Kimbrough nitro car servo saver, Hitec mg 645 steering servo, Powerline cnc machined and blue anodized engine mount. I attempted to install a RRP vented flywheel but due to the carbs forward position and large size the flywheel would not fit so i used the stock flywheel.
After running the 5 tanks of fuel through i had temps running around 240-260 and not quite as much power as some other 2.5 maxxes I have seen run, after much investigating I replaced the glow plug with a new Traxxas heavy duty plug and retuned the engine. Now it has gobs of power. Power wheelies and great top speed are no problem now, temps now at 220-230 degrees and as more fuel has passed the temps have dropped to around the 200 mark and the engine has loosened up some and the revs keep getting higher on top end. At close to less than a 1/2 gallon of fuel we clocked it on radar at 37 mph running on bowties. The bowties lowered the gearing due to about a 1/2 in reduced circumference. On stock rubber top speeds will be much higher, easily over 40 mph. It will run right at what most stadium trucks will run at top end with the stock gearing and could humiliate or run right alongside some RTR big block monster trucks such as the duratrax thunder quake and stock monster pirates. RC Nitro magazine got 44 mph out of their test truck.
I recently took the new Maxx to Real R/C Raceway in Pleasant Hill MO and many of the track regulars were surprised at what the 2.5 could do as far as power and I raced against several big block trucks there. Even after some very ugly crashes! and some huge air that went very wrong nothing broke on the truck and the engine flamed out once but started right back up. Thats yet another improvement over the many small blocks that i have owned and especially the pro 15 engine. Hot starts are not a problem, it starts easily and idles very smooth and does not load up excessively at all. To anyone considering a new maxx or anything with the new 2.5 engine i can highly recommend it.
Retail Price $380.00 to $410.00 at your local hobby shop, or favorite online
merchant.
Visit the TRAXXAS WEBSITE for more info.
