Our customers are a bad influence...

[Defiantspaz]

Pete,

Did you guys do a break in on the engine before you went at it, if you didn't you'll be adding that to the mod list in the near future.

It seems that the engine is slow to respond at lower revs, may be too rich on the low speed needle, but it sounded ok once it chewed through all the fuel up top. Also noticed a "gear drive sound", anyone who knows what a GM gear drive sounds like will know what I mean, your pinion to spur gear mesh may be too tight. This could be the reason the engine is slow to rev aswell. Check the mesh with a piece of standard weight paper, Basically loosen the engine mount screws, slide the paper in between the gears and hold the gears tight together with the paper in between and re tighten the engine mount screws. Remove the paper and you'll have a near perfect mesh.

An RC meet sound cool, I have a couple of trucks, a truggy, a buggy and a 2wd stadium truck. RC auto X at EFI would be cool.

I converted my 1/8th scale Kyosho Inferno MP7 Sport to a rally style car. Mine is 6 years old but you'd be amazed at the similarities.






I have an HPI K4.6cc, .28CI, 2.9 HP engine in mine. I crash it ALOT!

This is what it does to tire on pavement.

[EFI Logics]

Originally Posted by Defiantspaz

Pete,

Did you guys do a break in on the engine before you went at it, if you didn't you'll be adding that to the mod list in the near future.

It seems that the engine is slow to respond at lower revs, may be too rich on the low speed needle, but it sounded ok once it chewed through all the fuel up top. Also noticed a "gear drive sound", anyone who knows what a GM gear drive sounds like will know what I mean, your pinion to spur gear mesh may be too tight. This could be the reason the engine is slow to rev aswell. Check the mesh with a piece of standard weight paper, Basically loosen the engine mount screws, slide the paper in between the gears and hold the gears tight together with the paper in between and re tighten the engine mount screws. Remove the paper and you'll have a near perfect mesh.

An RC meet sound cool, I have a couple of trucks, a truggy, a buggy and a 2wd stadium truck. RC auto X at EFI would be cool.

I spoke to Trevor at Infernos, this guy said the same exact thing as you did about about checking the mesh. I ordered two extra spur gears just in case, but I will check it when I get the new axle.

I kinda broke the motor in, but not as suggested. He also said that these engines require at least 5 tank fulls before I will really see the performance from it. He told me the clutches are a bit loose because of the setup on the car, I ordered Carbon clutches to help with them, also a bit of a softer spring for engagement (Two different kinds). He taught me a few things about how to tune the engine in with a pyro gauge, I will be doing this as well when I get it back on the road.

I'm already looking into a larger engine for it, but I want to break myself in on this one first. There is a nice little hobby shop in Danbury that the owner is really cool with all of us, he's also going to help me dial this thing in as he seems pretty fluent in the Nitro stuff.

- Chris

[SLI99]

This was my old HPI....

[Jim511]

Chris whats the name of the shop in danbury? I've been looking for a better Local hobby shop that stocks more parts than the one I go to in fairfield.

[Defiantspaz]

Chris,

I recommend Rick Brake modified engines, http://www.rbmods.net/home.php

I have one of Rick STS D30M animals in my HPI Savage race truck.

The warm up vid > http://www.youtube.com/watch?v=pvQc3TnpirM
http://www.youtube.com/watch?v=vpsbvmLOfTc
http://www.youtube.com/watch?v=4GGKx7dJpD8
http://www.youtube.com/watch?v=J-WOgYz168c
http://www.youtube.com/watch?v=HpK2r7QBYQk
http://www.youtube.com/watch?v=2DdDEImzkIM

I do a very detailed break in on my nitro engines. If you want to know how I do it.

Originally Posted by Defiantspaz

The term "blipping" is what causes the biggest confusion. What is a blip? How do you go about producing a "blip"?

Think of the term "blipping" as "pulling the throttle 1/4 of full". The issue is that most people get confused during this stage of the heat cycle break in and consult the "when confused floor it" break in

After the static idle heat cycling you need to load the engine to seat the piston to the sleave. Too much load too quickly will destroy the engine and no enough will allow the piston to anodize and never seat with the sleave. The best way to load the engine is to drive the truck. To keep things under control and create some form of unified break in term "blipping" was chosen because a "blip" is a short duration operation. The short duration helps to control the overall load, BUT the force used during the "blip" determines the effective load the engine recieves.

I have come up with a more repeatable break in loading plan. I base everything off of a modified Traxxas/ heat cycle break in procedure. Traxxas got it right with their partial throttle for a desired amount of time method, but forgot about the initial wear the engine will see if it isn't heat cycled to match the piston to the sleave before load is applied.

Here is what I have come up with. The first 6 heat cycles should be short to get the engine used to expanding and contracting. Metals have memory and if you heat unlike metals together for too long they retain their shapes differently. You need to make sure the piston is at bottom dead center, BDC, and heat the engine until you reach 100 deg F and then start the engine and let it idle. While the engine is idling quickly, in under 2 minutes, get the engine up to 200 deg F and shut it down and return the piston to BDC. Allow the engine to cool to ambient temp completely, this is a major part of the cycling process. Repeat this for a total of 6 under 2 minutes to 200 deg F heat cycles. These first heat cycles work on the engines short term expansion and contraction memory.

Now it is time to work on the long term memory expansion and contraction of the engine. You will repeat the same process above but instead of a quick race to 200 deg F you want to spend 3 minutes slowly reaching the temp. This will allow the engines parts to become better seated to one another before they see any load. Repeat this for a total of 6 3 minutes to 200 deg F heat cycles. I know that 12 heat cycles is alot, BUT in the end the quality of the break in will show it's stuff.

After the 12 cycles then I go to the "blipping" part of the break in. First off when you blip the throttle you are just cracking it not going WOT. I think when people think of blipping they automatically think they need to floor the trigger and then let off. This is not the case and it is the problem that Rick was addressing in his break in plan.. I would just get the truck to move forward using no more that 1/4 throttle and then let off, this limits the force load applied to the piston and conecting rod as the break in with the sleave. I continued to do this in half tank intervals returning the piston to BDC and letting the mill cool to ambient after each half tank, I suggest the last half of the tank so you can control the temps better just don't let the mill run out of fuel. I continued this "blipping" for 10 half tank fulls

Next I went to half throttle bursts of 2 seconds. I would ramp the truck up to speed in 2 seconds reaching half throttle at the end of the run. stop the truck and repeat. Do not let the mill get above 210 deg F, if it does richen it up and continue. I did this for 8 tank fulls. At this point you do not have to let the mill cool down to ambient anymore, you can just refill the tank and continue with the break in.

I then moved on to 3/4 throttle bursts of 3 seconds. Same as above just takes more time and you use more throttle. Do not let the mill get above 220 deg F, if it does richen it up and continue. I did this for 8 tank fulls.

Time for some fun now! FULL THROTTLE bursts of 4 seconds. Do not let the mill get above 230 deg F, if it does richen it up and continue. I did this for 8 tank fulls.

Basically you want to expose the mill to varying levels of RPM, heat and load. As it starts to loosen up you will need to keep your self under control. Don't jump the gun and start reving it out until you finish the entire break in.

After all of the above was done I tuned the mill to hit 250 deg and drove the truck on pavement anyway I wanted. I would do full throttle runs, quick accellerations and wheelies if the tune would allow. Just remember to keep the mill fat and happy.

After 2 gallons were run through my RB STS I then tuned it for max power. This break in is what I have done for all of my mills and it make the mill very responsive and powerfull.

I have noticed that using this break in allows me to run slightly more fuel and still produce amazing power. Some people may disagree with running more fuel, but remember that the fuel also lubricates all of the moving parts so running a higher nitro % and more fuel isn't a bad thing. All of my friends have to tune their mills to the ragged edge of death just to keep up. My STS is happily rich and still rips the wheel off the ground with every prod of the throttle trigger.

Everything comes down to one thing, stress load vs repeatability. Think of it like a vertical line and a horizontal line shaped like an "L". Stress load is the vertical line and repeatability is the horizontal. You have a tangent conecting the two that will never grow longer. As you climb the stress load leg the tangent moves closer to the "0" side of the repeatability leg. If you reverse the process you lessen the stress load and increase repeatability.

My point is if you can find a better way to get the most out of your mill with out needing to push it to the limits of it's design you will be better off.

A prime example is my 3.3R JATO. I can do full throttle runs all day long and it never gets over 234 deg F, NEVER, and it is a Traxxas! Traxxas always run hot because they are so high strung. It always has a very strong fuel trail of smoke and most people say it is running way too rich, but it never makes puddes of fuel just tons of smoke. The combustion is very complete and this is a good thing. The seal between the piston an the sleave promote a complete burn and a ton of power. The JATO just rips the tires off it's rims. It is so fast you would swear it has a modded mill in it. My STS is the same way, tons of smoke with out alot of fuel liquid exiting the exhaust. If you do the break in right you will see a big difference in the way your engine produces the normal smoke trail. The better the combustion the more smoke you will see. There is a point where too much is just too much. If the engine is too rich it will barf out good amounts of liquid fuel along with the smoke. Just lean it out a touch so that just a small amount of liquid is coming out but the smoke is still strong.

I know this is one heck of a huge rant but this method has worked very well for me and I hope it works for any of you who have the time to see it through.

This is the only way I have found for me to get the "pinch" just right on my nitro engines. Takes a long time but is worth it.

If you have 2 tune the high speed needle first, the long post sticking out of the carb, then the low speed needle. this will get you close, then just tweak the needle to keep the temps where they should be. Also remember to take fuel away on hot days, summer, and add fuel for cold days. You will need to have two tunes unless your just going to run in the summer.

After run oil is also your best friend and is super cheap to boot.

[Defiantspaz]

SLI99,

That looks like an old HPI RS3. I had the blue Lightning and the yellow EVO 5 bodies for mine. I sold all my onroad stuff once I got my Traxxas JATO 3.3R.

[G4Broke_08STI]

Originally Posted by EFI Logics

www.infernosonly.com

These are the Kyosho DRX series.

or find a dealer in CT: http://www.kyoshoamerica.com/located...hp?location=CT

[ScrapinSTi]

nice chris... Need to add a temp fail safe to that list of parts.. It can be a lifesaver if you A. Lose radio range, or B. overheat the motor. I lost range on my TMaxx once out of nowhere... But it was ok.. the curb stopped it.. $75 later I was racing again...

http://www3.towerhobbies.com/cgi-bin...&I=LXJTW3&P=ML

While you can just use a Pyro gun, I like the temp fail safes, as you can just peek at it and not have to fiddle with the gun, taking off the body, etc... Especially since the kyosho doesn't appear to have a cutout for the cyl head..

I need to put my TMaxx back together and sell it so I can pickup one of these... This looks like it would be MUCH more fun.

[abnormal]

New toy perhaps....

http://www.infernosonly.com/Kyosho_M.../kyo31226b.htm

[G4Broke_08STI]

Originally Posted by ScrapinSTi

nice chris... Need to add a temp fail safe to that list of parts.. It can be a lifesaver if you A. Lose radio range, or B. overheat the motor. I lost range on my TMaxx once out of nowhere... But it was ok.. the curb stopped it.. $75 later I was racing again...

http://www3.towerhobbies.com/cgi-bin...&I=LXJTW3&P=ML

While you can just use a Pyro gun, I like the temp fail safes, as you can just peek at it and not have to fiddle with the gun, taking off the body, etc... Especially since the kyosho doesn't appear to have a cutout for the cyl head..

I need to put my TMaxx back together and sell it so I can pickup one of these... This looks like it would be MUCH more fun.

I was going to start looking for an onboard temp gauge today while ordering my "pyro gun" laser infrared surface thermometer - for RC and "grilling/cooking" ventures. LoL