R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Nitro On-Road > Onroad Nitro Engine Zone

Thread Tools Search this Thread
Old 08-27-2009, 04:39 AM   #16
Tech Regular
Join Date: Jul 2003
Posts: 498
Trader Rating: 4 (100%+)

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.
xspower is offline   Reply With Quote
Old 08-27-2009, 05:27 AM   #17
Tech Elite
M7H's Avatar
Join Date: Dec 2004
Location: The Netherlands
Posts: 2,191

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....
M7H is offline   Reply With Quote
Old 08-27-2009, 10:55 AM   #18
Tech Fanatic
nazwenhome's Avatar
Join Date: Feb 2007
Posts: 977
Trader Rating: 33 (97%+)

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.
Serpent S411 TE : ready to race
Tamiya TA05 VDF : sleeping mode
Align 450 sports v2 : tick-tock in progress

Last edited by nazwenhome; 08-27-2009 at 11:09 AM.
nazwenhome is offline   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off

All times are GMT -7. It is currently 08:42 PM.

Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net

SEO by vBSEO 3.5.0