My background with piped setups dates back 11 years now and includes 5 nationals top 5 placings, so I consider myself well versed enough to report on this. I’ve used OS46VF, OS46VF AAC, MVVS40, PA51, Jett/GMA 50, Jett/GMA 60 and now the Ro Jett. I was one of the many people who talked GMA into doing the 60. No intention to big note myself here, just many of you don’t know me. My findings so far on the Ro-Jett have been pleasant and are as follows.
It has a good broad needle range. Many of the engines I have used had a narrow “sweet spot”. They seemed to have a setting at which “it all came together” this was more predominant in the slightly higher timed ones, but still existed in most of them. (Personally I believe the lower timed engines are less govened by the pipe, but that’s not a bad thing). A bit rich and they fell off power, got lazy etc, a bit leaner and you had to hang on tight. The Ro-Jett needle can almost be used to throttle or dial in the speed you want, within limits naturally.
It has very good useable torque. In comparison to the setup I used at or nats this year I have been able to slow my lap times from 5.2 to 5.4 but with the same tension and authority in manouvers. This is on 69’ solid lines. It gives a much stronger overall impression. Some pipe experimentation also assisted in this result.
As with the way I ran the GMA 60 I never need to mess with pipe length once I’ve found the initial setting. On hotter or lower humidity days I just simply remove a head shim to give me some power back. This was important ability at the nats this year as the humidity dropped from 95% in the mornings to 23% in the matter of hours. A predictable engine was a big help. An alternative would be to have some extra higher nitro fuel on hand and mix different ratios to suit.
What I’ve found to work for me on my current 700sq 63oz model is the Eather #6 pipe and Eather 12x3.75 “red” undercambered 3 blade. The engine works equally well on the Eather 12.5x3.75 “green” 3 blade. In fact I bolted on 4 different 3 blades with varying diameters, pitches, and undercamber and didn’t need to touch the needle. That’s an ability I like, I can mess with props to deal with different conditions and don’t need a couple of flights on each to get the needle setting right. The SIG, Thunderbolt and McCoy 4 cycle plugs all work equally well.
I know some people had less than satisfactory experience with the GMA versions (no speaking ill of the dead here), but don’t let those experiences dictate your opinion of this new generation unless you have tried one for yourself. The GMA units worked well for me I’ve placed 3rd two years in a row with them, but I feel the new one will serve me even better. If you are thinking of one, go with the BSE case, it seems more temperature stable and needles better on the ground.
I understand Richard is pretty prompt on delivery too. Congratulations to Dub Jett and Richard, you’ve developed a good useable package.
BRI