Well, I haven't run like I have in then past years, so I haven't gotten a chance to really work with the engine especially since I am running 1/8 too, but wow, finally got it. I was having a problem with the low end like others, but really liked the mid and top end.. When I changed gearing for low end, it came alive , but didn't have that awesome wow topend I liked. Well finally it came all together. I went alittle over the 1.4 on the spring compression(where as i never had to go over 1.2 on previous engines for my RRR) and bingo. I am a happy man. Got the low end I was looking for, and really had top end that stay close to 1/8s on smaller tracks. Tuning was a little tricky and took a little getting used too, but I am realy gald I got the engine. I used the skyline pipe. One thing though, the engine runs hotter than engines I have used in the past. The manual says 259 is normal, I do not go by temps other than brake-in, but the engine has been living in the 275 range without showing any signs of pitting etc. So I was testing with a friend with a new nova 123 I believe, and we just kissed the cars. Since the pipe was so hot and thats where I got hit, the pipe was seriously damaged. Small price to pay for such awesome power. I am begining to see what this engine can do with all the right set ups. Hopefully I can check out the CRF clutches and pipes soon.