i was always thinking about this point, if the k4.6 is very strong and strong enough to make the savage go like mad then why did they make a new engine f4.6. why did they make a new engine for the savage X rtr 4.6.... they I'm curious why they didnt put the K in it as well. why did they make the strongest engine in HPI history if they wanted to make the newest savage the fastest. why did they make it the same as the K engine. they sould have made an engine that made a different between it and the K making the K a weaker link. i was thinkin more of the lines of PICCO .28 HP area. i was hoping the F was going to be a 3+hp engine.
all I'm saying is why bother make a brand new engine if it was going to be the same power as one that already exists.....????? THIS IS THE REAL MYSTERY..
First, you are pointing out the new F4.6 that is in the Savage X RTR. RTR's are supposed to be easy to get going and they usually don't have all the extra goodies that the kit versions do.
Again look at the needs of the new nitro RC owner, the new engine needed to be easy to tune and have a predictable power band.. The older F4.1 was a good mill, BUT it did lack the low end that most Savage owners like to see. Enter the new F4.6. The F4.1 made 2.75 hp at an undisclosed RPM and had a 7mm carburator. The new F4.6 makes 2.9HP @ 32,000 RPM and has a slightly bigger 7.5mm carburator. Considering the nature of RTR's the F4.6 seems like a very good choice. The added power and torque just make the RTR that much better. The F series mills have always been about durability over huge power. Less RPM means less wear but the 2,9HP rating means the mill has enough juice to keep it interesting to the owner longer than the F4.1 would.
On to the Savage Xss and the K4.6. The K series mill is a twin in most respects to the Axial .28 Spec 1. This close relation means the K4.6 is designed for max speed at the expense of some durability. I would bet that the new F4.6 weighs more than the K4.6 too. Weight savings, increased RPM and a bigger carb mean that the K4.6 will most likely have more midrange and topend power than the F4.6. Just because they both say 2.9HP doesn't mean they make the same power. Remember that torque is what gets you off the line and horsepower is what keeps you moving. Power has two measurements, you need to consider both during this comparison.
RC companied do things in stages. They want to gauge market responce to any changes they make before they commit the new ideas to their entire product line. I have heard rumors of an updated K4.6 that include the crank form the Axial .28 Spec 1 RR and a K4.6HO that is supposed to have most of the upgrades done to the Axail Spec 1 RR.
I beleive that HPI has a bigger K series mill in store for the next generation Savage Xss, maybe a K5.0, who knows? The fact is that the Savage X RTR is a better Savage with the new F4.6 and by setting a new standard for the entry level Savage it will make the entire Savage line better in the end.
Look, Cheverolet makes the Corvette. For years it was their top dog, no questions asked. That was until Chevy make the 1993 Camaro Z28 sporting a slightly detuned Corvette 5.7L. In 1994 Chevy made the Camaro Z28 SS which was so close in performance to the Corvette that Chevy needed to make the Vette better or the sales would have declined to just the Corvette enthusiats only. In the end Chevy made a better Vette and has continued to do so from that point on. I expect HPI to do the same with the Savage Xss.
