Everybody that has one of these hpi wr8s recommends to upgrade the servo at some point in the near future. My question is how do I know what servo I need? What makes a better one than the one I have? Are there different sizes?

Thanks for the help

Jake

I can't believe they put that stock servo in there from the factory....well yeah I can. A lot of, if not all, companies skimp on the servos and/or electronics in their RTR cars/trucks. That drives me nuts, not being able to buy a kit and put in what electronics that I like/choose. Looks like a standard size servo that is needed for that HPI. Look for a metal geared servo with more torque.

For a suggestion....Hitec HS-625MG High-Speed 2BB Metal Gear Servo for an analog servo, or maybe step up to a digital version... Hitec HS-5625MG High-Speed 2BB Metal Gear Servo. They are my go to servo for heavier RC vehicles. I've tried a lot of the super low budget servos; with specs too good to be true, and I don't skimp on what steers my cars anymore. IMO those Hitec servos are just superb for the money. You want more torque/speed in a servo...ya gonna need more $$$.

Everyone has their favorite brand(s) of stuff; I'm just throwing out a suggestion that has survived 5+ years of my abuse with only one replacement set of the gears needed.

Looking in the manual or you can download it at HPI...your model came with a "standard" sized" servo Length: 1.59" (40.6mm)Width: 0.77" (19.8mm)Height: 1.48" (37.8mm). I see that the HPI SF-10W (stock servo):
only produces 36 oz/in of torque
and has some type of plastic gears in it
I'm also guessing there is no bearings either

Those servos that I linked in the above post:
94 & 130.53 oz-in of torque to push the the wheels/tires/linkage with ease
Along with ball bearings to make servo more durable/last longer...
They have metal gears to handle more stress and will strip less than plastic gears.

Oh, the downside on the Hitec servos that were linked...they are not waterproof.

Thank you so much for the info

HPI put a 36oz/in servo in the WR8????? Seriously? What a waste of effort! Why not just use a rubber band? HPI has NOT been making the greatest decisions of late...... I'm just glad they did not end up with the OFNA brand. They would've ruined it.

Can't really go wrong with Hitec. Any servo listed as "standard size" should fit. Then just pick the one with the amount of torque you want. Start with the stock servo's torque rating, then double it. Or, triple it, depending on your budget.

The 5625MG is the one to go for, you get exactly the right upgrade in terms of speed and torque for the extra 10 bucks that you need for the slightly oversized WR8. I rather miss mine.