Engine Help

[pankey35OSU]

I am running the O'Donnell SS in my OFNA buggy and the engine in great. I have been having a bit of trouble getting it tuned though, I am getting good throttle and smoke until I pull to full throttle and then the engine almost hick ups kicking the RPM'S down really low, am I too rich still or to lean. Also I am looking for a tuned pipe that fits this engines performance to add a little more bottom end, the engine is rated to 42000 rpm so the top end is there I just need a little more bit from a stand still?


-Keith P.

 

[RC Addict]

Is it bogging down or more like stumbling and stuttering? If it sounds like it is bogging down a bit from a rich tune that is an easy fix. One way to tell--get it warmed up and then floor it. If it bogs again go 1/16 to 1/8 of a turn leaner. If it helps that is the way to go. If it still does it or gets worse then it's more-than-likely an air leak leaning you out.

 

[pankey35OSU]

Ok I will try that. You said air leak? Where and what should I check for that. The motor is only about a week and a half old and I have only put about 7 tanks through it. O'Donnell recommended 8 tanks to complete the break in and the 7th and 8th tanks are tuning tanks and I havent jumped the car or bashed it yet because I plan on just racing it and not bashing with it.

 

[Metalhead Matt]

Even new engines could have an air leak. The carb throat, backplate and header should be sealed with high-temp, sensor-safe copper rtv. If your temps continue rising, even if your richening it, the suspect would be a leak. Tank caps and fuel line can leak, too.