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Old 05-29-2013, 01:02 PM
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Default RE: Hpi Sprint 2 flux upgrade 90+mph

Funny.. I said the same thing as Foxy in not so many words on another post, but I guess the OP had to hear it from another source. I was nice what I said about the Traxxas setup.. Foxy was a bit more blunt...LOL... I shortened my other post because I didn't want to hijack the other post... I have alot of experience with brushless touring cars as do most of my friends.. We run them every week in a class we like to call STUPID class.. Its all RS4's and Sprint2's with the occasional Tamiya thrown in for target practice. What we found out very quickly is these cars are not drivable at anything over about 60mph.. Why you may ask.. They have a nasty habit of trying to impersonate an airplane.. and not very good at it. They are just plain too light to go much faster without taking off. Sure you can spend tons of money making a custom body, but its not a car at that point. We like to go very fast, but not at the expense of proper handling. What we settled on was this ... 5700-5900 2 or 4 pole castle motors.. even a few HK motors hang in there. nothing usable over 2S... we've tried 3S but the tires just shred or the car flips over.. neither is a good thing. With proper gearing we are running around 60mph on the straights but really don't go over 50's much.. Its plenty fast.. I know Foxy mentioned 4 poles as a good choice.. My honest opinion it really doesn't make a difference.. Your gearing and battery do.. Your gearing will always be limited in a touring car to something on the order of around 30/84.. or near that.. Good combo of speed and heat control.. You can gear higher for more top end but overheating is a strong possibility. We have tried traxxas motors on occasion..but in every touring car they were slower and a few times the magnets broke off the shaft killing the motors. Not sure why, but its happened a few times.. maybe the constant rpms of a touring car are too much for it. For real speed runs I would do exactly like Foxy said.. 1/7th car and a 2200 1/8 motor on 6S.. You will hit 100mph.. But at a cost... LOL Lastly, before any of the traxxas lovers come to crucify me.. I own many traxxas products 10 at last count. I just don't like their motors/esc.. Nothing special and no control over the parameters of the esc... All my traxxas electric vehicles have had the traxxas electronics pulled and replaced.