R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Nitro Off-Road

Reply
 
Thread Tools Search this Thread
Old 03-17-2010, 06:42 PM   #1
Tech Elite
 
Join Date: Mar 2009
Posts: 3,657
Trader Rating: 5 (100%+)
Default tunning questions

Some question i would like help with that the tuning bible will not answer.

I am breaking my engine in gradually instead of the heat cycle method. Started out rich with 20% byrons, idled for 2 tanks up to temp (through the whole break in, up to temp, cool down, BDC etc). Bottom end is set to a low idle. idle screw open a bit.

bout 4 tanks, 3 minutes at a time at slow throttle.

lean a couple hours on the top

4 more tanks medium 3 minutes at a time.

lean a little like 1 hour

4 more tanks, each time i go until the engine gets below 160. bout 5-6 minutes.

I am now switching to 30% and put the extra shim just for a couple tanks.

This is where things get blurry. When i start tuning.

I know to start with the high end, but it's really hard for me to tell when it's right when the low end is so rich. The textbook way for me to do it would be to get the engine to idle, tune the high speed, tune the low and set the idle screw.

I want so bad to tune the low down so i can get a better read on the high end, but that is when i screw the tune up.

So? How do i tell that my high end is right and ignore the bog of my rich low end? Seems to me, that i should tune the low end to within about 75% of max power right? This is what i want to do, but want to make sure that my procedure is right.

furthermore, my engine is not "awake" so it will not pull the rpm's that in my mind tells me it's "time to tune".

furthermore still, if i start leaning it down to "speed up" the break in process or "heat cycling" as you guys call it. When i read my plug and wipe it on my hand it always has the metal residue, which i know will happen to have it "break in", but i feel that nursing the process will help in the longevity of my motor.

So.

do i "tune it up" to speed up the breaking process?

or

wait for it to break in and "wake up", then tune it from there?

and finally,

if the engine is up to temp, then rich is good. RIght?

You have no idea what it's like to be me.
__________________
"You are not understanding the fundamental principles of my fragmented personality"

Mugen
dreaux is offline   Reply With Quote
Old 03-17-2010, 08:32 PM   #2
Tech Adept
 
n.c.trigerhappy's Avatar
 
Join Date: Dec 2009
Posts: 101
Default

OK, I'm NOT the the most qualified guy on the forum to tackle all this, but I have learned afew things lately that may help.

Is your engine an rtr type, or a more expensive-high silicone piston, xtra hard metals, etc. type engine?

I've just today finally got a whole gallon(+ a quart) through my novarossi fms, and it still has some "pinch" left in it. DON'T RACE TUNE IT UNTIL THE METAL PINCH IS GONE!!!!!!! Sounds wierd, I know! I hear guys all the time say, "Im at 3-1/2 gallons (or what), and she's still got pinch!" All that's doing is SLAMMING the con-rod at race tune, and gouging (microscopically) the sleeve, so when it DOES loose its pinch....it's toast!

I asked about the quality of your engine because, if it's a good one, break-in is measured in GALLONS, NOT TANKS!!!!

Mark (powerhouse) said the #1 mistake is to race tune before it "drops it's nuts." You're killing the longevity that way!

Lastly, ALWAYS, ALWAYS, AND EVERY SINGLE TIME, pre-heat (total saturation) the block, AND chassis before EVEY SINGLE START! Heat cycling is NOT a cool-down, then fire back up and "get it up to temp." This too kills longevity ( and con-rods). Basically, don't push it.
__________________
SAVE THE PLANET!!!!!!!!!!!!!!!!!!!!!( from the global warming SCAM!)
n.c.trigerhappy is offline   Reply With Quote
Old 03-17-2010, 09:11 PM   #3
Tech Elite
 
Join Date: Mar 2009
Posts: 3,657
Trader Rating: 5 (100%+)
Default

Quote:
Originally Posted by n.c.trigerhappy View Post
OK, I'm NOT the the most qualified guy on the forum to tackle all this, but I have learned afew things lately that may help.

Is your engine an rtr type, or a more expensive-high silicone piston, xtra hard metals, etc. type engine?

I've just today finally got a whole gallon(+ a quart) through my novarossi fms, and it still has some "pinch" left in it. DON'T RACE TUNE IT UNTIL THE METAL PINCH IS GONE!!!!!!! Sounds wierd, I know! I hear guys all the time say, "Im at 3-1/2 gallons (or what), and she's still got pinch!" All that's doing is SLAMMING the con-rod at race tune, and gouging (microscopically) the sleeve, so when it DOES loose its pinch....it's toast!

I asked about the quality of your engine because, if it's a good one, break-in is measured in GALLONS, NOT TANKS!!!!

Mark (powerhouse) said the #1 mistake is to race tune before it "drops it's nuts." You're killing the longevity that way!

Lastly, ALWAYS, ALWAYS, AND EVERY SINGLE TIME, pre-heat (total saturation) the block, AND chassis before EVEY SINGLE START! Heat cycling is NOT a cool-down, then fire back up and "get it up to temp." This too kills longevity ( and con-rods). Basically, don't push it.
it's a ninja. And this is what i mean. That are 2 schools of thought on how to break in a engine, and this is one and this is what i am doing. But all you hear is the heat cycle method which i tried twice and did not have the power and longevity i had hoped. I ended up leaning it before it was ready going by the method outlined in this forum and i don't like it.

running rich is good imo if the motor is in the right temp range. I have put over half a gallon and the break in is going beutifully. It really impossible to tune before it lets you know it's ready because it's not pulling the tourque and rpm that the engine is designed for.
__________________
"You are not understanding the fundamental principles of my fragmented personality"

Mugen
dreaux is offline   Reply With Quote
Old 03-17-2010, 09:45 PM   #4
Tech Elite
 
Racecrafter's Avatar
 
Join Date: Apr 2007
Location: RC Mecca
Posts: 4,138
Trader Rating: 25 (96%+)
Default

You need to make sure you heat the engine up to at least 180 degrees and it needs to stay above that while it is running. I prefer to use a non metallic engine stand for break in to eliminate the depletion of heat.

When you break an engine in cold it will break in faster and thus longevity is compromised. Not only the stress it puts on the rod but the piston breaks in at a smaller diameter from the extra squeeze from "pinch" in a lower temp sleeve. When the engine comes up to operating temp it will lose compression, thus power, fuel mileage and sometimes tuning will get sketchy depending on the engine brand.


Stick to the bible and thou shalt be saved!! (A lot of frustration, time and money)
__________________
Jimmy Wright

www.trackstarrc.com ~ www.facebook.com/TrackStarRC ~ Home of the 2x's Stock Nationals Champion TS-Gold & TS-Black tire sauce, TS-1+ lubricants, TS-Precision bearings, XRG Xtreme Racing Grease, Scale Auto Engineering, ElevenTech, WRD2, Carbon 12, Stiff Products
Racecrafter is offline   Reply With Quote
Old 03-18-2010, 03:15 PM   #5
Tech Adept
 
n.c.trigerhappy's Avatar
 
Join Date: Dec 2009
Posts: 101
Default

Quote:
Originally Posted by Racecrafter View Post
You need to make sure you heat the engine up to at least 180 degrees and it needs to stay above that while it is running. I prefer to use a non metallic engine stand for break in to eliminate the depletion of heat.

When you break an engine in cold it will break in faster and thus longevity is compromised. Not only the stress it puts on the rod but the piston breaks in at a smaller diameter from the extra squeeze from "pinch" in a lower temp sleeve. When the engine comes up to operating temp it will lose compression, thus power, fuel mileage and sometimes tuning will get sketchy depending on the engine brand.


Stick to the bible and thou shalt be saved!! (A lot of frustration, time and money)

+1 !!!!!!! That's zakly what I was sayin'!
__________________
SAVE THE PLANET!!!!!!!!!!!!!!!!!!!!!( from the global warming SCAM!)
n.c.trigerhappy is offline   Reply With Quote
Old 03-19-2010, 08:48 AM   #6
Tech Initiate
 
Join Date: Jan 2009
Location: Kansas City
Posts: 43
Trader Rating: 1 (100%+)
Default

I'm not too good at break-in, but remember that the high speed needle controls how much fuel gets into carb so adjusting the high speed needle affects the adjustment of the low speed needle. If you are adjusting the low speed needle first then recognize that you will always have to go back and readjust your low speed needle after adjusting the high speed needle to hit a good tune.
__________________
Jammin' X1-CR
Jammin' X2-CRT
Stock Slash
B4 Late Model
Still looking for driving skills. :confused:
improvement54 is offline   Reply With Quote
Old 03-20-2010, 02:57 PM   #7
Tech Adept
 
n.c.trigerhappy's Avatar
 
Join Date: Dec 2009
Posts: 101
Default DON'T FEEL BAD!!!!!

This too is true. If you change the high needle and it starts acting funky- especially idle and "snap", tune the bottom just a little OPPOSITE of whatever you did on top.

I shouldn't even be on this thread giving advise though!

I spent 1/2 a day yesterday tuning, "de"-tuning, cursing and spitting trying to get my (1 gallon old) novarossi fms to run consistant, and NOT FLAME-OUT!!! I tried EVERYTHING, then (today, at the track) my buddy said, "have you tried changin' the plug?"----------- BAM!!-purred like a kitten, ran like a cheetah on crack, and idled beautifully!
__________________
SAVE THE PLANET!!!!!!!!!!!!!!!!!!!!!( from the global warming SCAM!)
n.c.trigerhappy is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Motor tuning questions Xrayskid Electric On-Road 52 05-29-2006 05:48 PM



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 10:18 AM.


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