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Old 08-27-2009, 05:39 AM   #16
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Originally Posted by aussies1129 View Post
I have a had about 4 or five piccos to date including the edo tune .12 and have found that they lean themselves out over a race but when the engine was running at its best I would be around the 110c mark with a TH picco plug, if my bottom was to lean then temps would really skyrocket. also I cut out all of my rear window and both front window with a legal size hole at the front about 60mm.
The engine really only leans out when the low speed needle is not set right. The most common thing that I see with the guys running a picco motor is that the bench tune the low speed get the engine so it will idle a lifetime and then go run it and look amazed when the engine is 300 degree's on the track after a 3 minute power run. The low speed needle can be set close on the bench cannot have the engine idle for a lifetime the needle is flat out to lean. The engine by itself is a cold nature engine therefore needs to warm up before it is running well seems rich but in 2 minutes will be fine. The Picco does not tune like a nova. Keep this in mind the low speed needle is more time then not the reason the engine is hot. If the engine lays over then the high speed is closed to much. Listening to the engine and understanding what is going on is key.
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Old 08-27-2009, 06:27 AM   #17
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Originally Posted by Picco12 View Post
Yeah, the holes etc are all present.

It's just that I was advised to keep it under 110c, which at this moment is not possible because otherwise it will be just to rich. Leaning it out the temp goes up to the 120/130c range. I'm still pretty much a beginner, and the guys advising me won several championships for years in a row, so (I guess) they do not talk poop.
But because i'm not able to run alot in the weekends, and are mostly running on the circuit on my own during the week, I didn't know how bad it would be if temps were up. I must say the weather overhere is now also 10c hotter than is normal for these areas.

Although a Picco engine is broken in fairly quickly, I have seen drivers still make the mistake to lean the engine to fast during break in. Then the amount of pinch still left in the engine will also create heat... and the engine will not make top speed although it seems to be set correctly... It is difficult to give a figure in an amount of fuel, an engine needs to be broken in, cause it totally depends on how tight the liner fits the engine case. I always check at the end of the break in process how much pinch the engine still has left, right after running it when it is still warm... If it is still to much, continue the break in process, and be sure you don't run the engine above 80C / 180F, otherwise it will take a very long time....
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Old 08-27-2009, 11:55 AM   #18
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Originally Posted by Scott Fisher View Post
I don't know where this idea of running the bottom end rich got started, but I find it a bit humorous. It needs to be tuned correctly. Obviously there is a window where the engine will run but perform differently, but if it is rich then it needs to be leaned out until it is properly tuned.

When you guys say the bottom end needs to be rich, how long will your engine idle? Assume the engine is at operating temp etc.... If your engine loads up and dies relatively quickly, then it is too rich. If it doesn't load and die quickly then it isn't rich, its tuned properly.

They way you guys put it, you need to mistune the bottom end for it to be tuned correctly, which is a contradiction.
cant deny optimum tuning as another added advantage, no offense but right now its about a game of compensating performance and ability to hold that operating temperature at a given period. mistune is just an option, but it works at an expense of acceleration during first few minutes of my first tank.
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Last edited by nazwenhome; 08-27-2009 at 12:09 PM.
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