Originally Posted by
Hobbsy
I got 10000 rpm w/ my "stock" Saito 100 on APC 15x6 prop and 30% nitro fuel. With 15% nitro fuel, I'd get 9600. (quote by Sean Y. Chen
The post right above this one was an APC 15x6-W at 9,750 doesn't say what fuel. These are typical Saito 100 numbers. Actually 1.04.
So you are pulling right at 1.8-1.9 HP. Right in the ballpark for the FA-100. However, without a "control" such as a pull with another engine of know power output done at the same time, there can be some significant variance in output due to atmospheric conditions and/or altitude.. I've seen as much as 300 RPM variance from different days with the same (Saito) engine.
I've seen as much as 50 HP variance in my 5.7 3rd Gen Hemi at different times on the same day at the track. I've seen as much as 100 HP difference at tracks with differing altitude and atmospheric conditions. That's a 20% variance.
Since I have a control engine for comparison, I can make a valid determination of the relative power output when I test my FA-115.
Now that hunting season is over and gun projects are winding down I have several engine tests to do, including the various combinations on a Saito FA-171 (180 top end on stock 150 crank) including 2 different rod lengths (FA-150 & FA-180) and 2 different piston combinations (FA-180 & FG-57) that will cover a CR range of about 7:1 to 15:1 if I can get sufficient piston/valve clearance for the later
BTW; An FA-180 isn't 1.8 cu in, it's 1.77 cu in so the change from the 180 to 150 crank does't affect displacement significantly when both have a 180 top end in place. (.07 cu in)
Then there is the FA-115 on both GI and CDI and the FA-220 (which arrived yesterday) with GI and CDI in addition to CDI high compression.
But 1st, it has to get above freezing due to the fact that I can't afford to heat my shop when it's sub zero. It was -5F this morning INSIDE the barn and I doubt that the garage was much warmer..