Switched from Touring Cars
12-19-2006, 01:59 PM
#1
Switched from Touring Cars
Hi All,
I have just switched from Touring Cars and I'm now starting out in 1/8th Buggy racing.
I have a 2 year old Hot Bodies Lightning 2 with a brand new Picco P7.R Engine ready to be started. I have all the required equipment to run the car in competition, I would just like a bit of help running the engine in. How should I set the fuel mixtures? How long should I run the engine on the box? etc etc. All help is welcome. Can't wait to get this powerhouse into my soon arriving Team Magic M1B.
Kind Regards
Paul
I have just switched from Touring Cars and I'm now starting out in 1/8th Buggy racing.
I have a 2 year old Hot Bodies Lightning 2 with a brand new Picco P7.R Engine ready to be started. I have all the required equipment to run the car in competition, I would just like a bit of help running the engine in. How should I set the fuel mixtures? How long should I run the engine on the box? etc etc. All help is welcome. Can't wait to get this powerhouse into my soon arriving Team Magic M1B.
Kind Regards
Paul
12-20-2006, 09:01 AM
#2
Hi Paul,
I too switched from electric to nitro just resently. You'll love 1/8 scale offroad.
Running your engine in on a box is an old school method that some people still use but in my research, I found a better way.
The idea is to put the least amount of stress on the engine at break in. When an engine is up to temperature, the sleeve expands to create the ideal "fit" between the piston and sleeve. On a new engine, this ideal "fit" doesn't happen until the cylinder head expands with temperature and the piston "wears in" to the correct tolerance. If the engine is cold, the piston can "wear in" too much, shortening the life of the piston and sleeve. What most people do is heat the cylinder head with a heat gun prior to starting a new engine. This expands the sleeve and lets the piston wear in correctly as it is under less stress.
Now on to break in.
Make sure your idle is set correctly. You should have no more than 1 to 1 1/2 MM gap between the slide and the carb inlet (looking into the carb with the air filter removed).
Grab a heat gun and heat the cylinder to 200 degree's (give or take). Make sure your high end needle is set rich (Follow the manufacturers instructions on break in needle settings) Start the engine and drive the car around for about 5 minutes at this rich setting using no more than 1/4 throttle. Shut the engine down and make sure your piston is at the bottom of it's stroke (you don't want the piston stuck at the top of the sleeve when it cools down). Let the engine cool completely.
Do this about 5 or 6 times or for about 5 or 6 tanks of fuel.
From there you can start to lean out your high speed needle and hour or two at a time until you start to make good power.
That should get you 90% there.
After that, race tuning to the optimum needle settings is something I'm still working on. The needle settings constantly change due to air temperature and conditions. Someone at your track should be able to help you with that.
Hope I made sence!!! There will be many different oppinions on engine break in but this is what works for me.
I too switched from electric to nitro just resently. You'll love 1/8 scale offroad.
Running your engine in on a box is an old school method that some people still use but in my research, I found a better way.
The idea is to put the least amount of stress on the engine at break in. When an engine is up to temperature, the sleeve expands to create the ideal "fit" between the piston and sleeve. On a new engine, this ideal "fit" doesn't happen until the cylinder head expands with temperature and the piston "wears in" to the correct tolerance. If the engine is cold, the piston can "wear in" too much, shortening the life of the piston and sleeve. What most people do is heat the cylinder head with a heat gun prior to starting a new engine. This expands the sleeve and lets the piston wear in correctly as it is under less stress.
Now on to break in.
Make sure your idle is set correctly. You should have no more than 1 to 1 1/2 MM gap between the slide and the carb inlet (looking into the carb with the air filter removed).
Grab a heat gun and heat the cylinder to 200 degree's (give or take). Make sure your high end needle is set rich (Follow the manufacturers instructions on break in needle settings) Start the engine and drive the car around for about 5 minutes at this rich setting using no more than 1/4 throttle. Shut the engine down and make sure your piston is at the bottom of it's stroke (you don't want the piston stuck at the top of the sleeve when it cools down). Let the engine cool completely.
Do this about 5 or 6 times or for about 5 or 6 tanks of fuel.
From there you can start to lean out your high speed needle and hour or two at a time until you start to make good power.
That should get you 90% there.
After that, race tuning to the optimum needle settings is something I'm still working on. The needle settings constantly change due to air temperature and conditions. Someone at your track should be able to help you with that.
Hope I made sence!!! There will be many different oppinions on engine break in but this is what works for me.
12-20-2006, 07:01 PM
#3
Like Mr. Ames...LOL...I'm another electric-to-nitro convert. Here's how I do it on mine for mixtures:
For WOT, I richen it until it won't pull hard, then lean it out 1 "hour" (1/12 of a turn) at a time until it pulls cleanly all the way...then STOP. You'll see really quickly where it needs to be, but always go from rich and only lean it as much as you need to to bet it to pull cleanly. The fast guys may go closer to optimum, but the biggest thing is to keep it "happy" and running nice.
For idle and low-speed, it's a back-and-forth process. To start, set the throttle where the slide is open 1mm or so...that's where you start. Your manual may have a different spec, if so use that. To set the idle mixture...again, tune from rich and just lean it a little until you start to get a smooth pull from idle. Start rich where it blubbers and stutters when you apply throttle and go 1 "hour" at a time towards lean.
Don't get fixated on temperature like some guys...if it's happy, tuned from rich and it pulls clean, then the temp will be fine.
I tune this way on OS motors and I haven't hurt one yet and they hardly ever flame out. Your mileage may vary on other motors, but this should get you in the ballpark and keep it alive during your learning curve.
For WOT, I richen it until it won't pull hard, then lean it out 1 "hour" (1/12 of a turn) at a time until it pulls cleanly all the way...then STOP. You'll see really quickly where it needs to be, but always go from rich and only lean it as much as you need to to bet it to pull cleanly. The fast guys may go closer to optimum, but the biggest thing is to keep it "happy" and running nice.
For idle and low-speed, it's a back-and-forth process. To start, set the throttle where the slide is open 1mm or so...that's where you start. Your manual may have a different spec, if so use that. To set the idle mixture...again, tune from rich and just lean it a little until you start to get a smooth pull from idle. Start rich where it blubbers and stutters when you apply throttle and go 1 "hour" at a time towards lean.
Don't get fixated on temperature like some guys...if it's happy, tuned from rich and it pulls clean, then the temp will be fine.
I tune this way on OS motors and I haven't hurt one yet and they hardly ever flame out. Your mileage may vary on other motors, but this should get you in the ballpark and keep it alive during your learning curve.
12-21-2006, 03:22 PM
#4
OK This has all been really good. I've had a conversation with my LHS/Track owner and he is going to help me but this advice will certainly be good for future reference. How long am I going to be able to get out of an engine? I will be racing once every two weeks and there will be 8 5 min races plus practice in each.
Kind Regards
Paul
Kind Regards
Paul
12-22-2006, 08:14 AM
#5
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