Which is better Heat Cycle or Factory Recommended Break-in?

[RobH]

All of my engines so far, I've followed the factory break-in instructions to the letter. As I've been reading here and there, I'm picking up that not everyone follows the factory break-in. Instead, some like to do what I think is commonly reffered to as a "heat cycle" break-in.

Here is an example sniplet that I found in some guy's auction for an engine he broke in:

I broke this in pro-style. The engine was pulled apart, checked for burrs and metal in the bearings then bolted to the stand, and propped and piped. It was pre-heated with a heatgun til the head and cylinder temp was 195 degrees then started and run up to operating temp 215 - 220 with the richest setting possable at WOT. It was properly run and heat cycled til the break in was complete. Has never gone over 220 but was never run under 195. This is to ensure the piston and sleeve did not wear out during the break-in process but the bearings and con-rod are properly seated! I preheat all my glow engines this way even once they are in the car to ensure the piston and sleeve do not prematurely wear out and to ensure the most power possible .

I also found a similar break-in process when reading an article by Ron Paris:

http://www.parisracing.com/engine_tuning_with_coversheet.htm

This is a long article. Do a text search for "Your new engine’s first run" if you want to read the part I'm refering to.

Ron Paris does talk about reading the instructions from the factory, but only to find the needle settings for break in. He doesn't instruct people to perform the factory recommended break in. Instead, he just unloads how it should be done.

My 8-port instructions had me idling 4 tanks full of gas through it. The temp never got over 180. They accually went down. 170 ... 160... 150... 145ish. I though it was odd, I did it anyway. Now, I'm concerned that maybe a heat cycle type thing would have been better.

Can someone explain the advantages to doing a "heat cylce" break in? Also, maybe one should do both break-in processes?

Thanks in advance for information you guys can give.

-Rob

 

[FlyinRazorback]

I heat cycle my engines, using Stephen Bess's method. Here's how it goes.

Fire up the engine, set the car on the ground and start running it while slightly rich. Do not run it hard, but get the temps up to about 180-190. Run it for 2-3 minutes, shut it off, allow it to cool down completely with the piston at BDC. After it has cooled, repeat the above step until you have ran it a total of 15 minutes (about 5 cycles).
Now go to 3-4 minute intervals, and get the temps around 200-210. Remember to allow the engine to cool completely after each cycle. After about 25-30 minutes total time of cycling you are ready to race tune your engine.

I have been using this method and it works very good. The conventional method of idling it and running it really rich puts alot of stress and premature wear on the piston and sleeve. Since my buddies and I have gone to this method our engines are lasting longer and are stronger.

 

[RobH]

Thanks FRB. That's exactly what I was looking for.

For those reading this thread that would like more information on Stephen Bess's heat cycle method, here is some more inforamtion for you:

I stumbled on this page via google search:

http://www.johnnycoolguy.com/JCGR/tables_site/main_pages/tech_break-in.html

If you are still idling at least a tank through during break-in, you're using the old-school accepted method (still works well for some!) but it's not the method that the top engine guys (Ron Paris, Dennis Richey, Rody Roem, Michael Salven are just a few I've spoken personally with about this) recommend anymore.

From the very 1st time you start your engine, plop the car on the ground & begin running it in a parking lot in 2-3 minute intervals, tuned only *slightly rich* getting the temps up in the 200F range on a normal day. Every 2-3 minutes, shut the engine down & let it cool completely with the piston at BDC, and then fire it back up; continue this cycle until you've run 15 min or so, and then bump up to 3-4 minute intervals. Vary the RPM and don't be afraid to get the temps in the 200's. What you want is heat cycling of the components without the incredible stress that comes with breaking an engine in when it's overly rich & cold. After cycling the engine in this mannerfor about 20-25 total minutes, it'll be ready for the track and race tuning. I realize this method goes against the old-school "idle on the box" routine, but you'll be amazed once you've completed this break-in routine, your OS will still have amazing pinch w/out sticking at the top AND your OS's compression will last far longer than it will with the "old school" method.

You say you run the engine at "factory settings" for the first FIVE tanks? That alone causes lots of stress, as the factory OS settings are very rich on every OS I've ever owned or tuned. The piston & sleeve haven't expanded to operating temps, and every time the engine turns over, the piston slams into the pinch zone at TDC. The not-so-surprising result can be a cracked con-rod at the crank pin--that's where the majority of the stresses occur as the engine turns over. I've only heard of about 6-8 OS engines breaking con-rods, and they're ALWAYS during the first gallon...and almost every time it's because the guys have performed the break-in procedure you described. Doesn't seem like a mystery as to why it's happening. Drawing out the break-in routine really stresses the engine & actually wears away compression along the way. This method I've outlined will feel weird at every step, but after you try it once, you'll notice a big difference in your engine's performance & lifespan.

Hope this helps; give this break-in method a shot--you have nothing to gain except longer life & more power

-Rob

 

[imnotsure]

I think i'm going to have to try this with my .12 hell if I it screw anything up, there cheap to replace.:thumbup:

 

[mcvickj]

Interesting. I might have to consider breaking in my Hyper 8 this way. I would still like to hear more opinions on this. If the heat cycle method is so much better why do the engine manafactures still tell the users to do the idle method?

 

[Nitroaddict]

Originally posted by mcvickj
Interesting. I might have to consider breaking in my Hyper 8 this way. I would still like to hear more opinions on this. If the heat cycle method is so much better why do the engine manafactures still tell the users to do the idle method?

thats my philosophy too, mcvickj. If it aint broke, dont fix it.

I'm sticking to the original plan until someone from OS tells me otherwise, lol. Although, i would be willing to try it on some junk engine that i got for free or something, but not on my VO1B, lol!

 

[FlyinRazorback]

NA, I've had 3 v01b's, the last one I broke-in using the heat cycle method and after 2 1/2 gallons it still has a ton of rip. It still has a pinch at the top also.

 

[Nitroaddict]

i believe u, flying, I'm just scared to try it when what i do now works for me. Cool that there is another way, though.

 

[wdavidhicks]

I'm really likin' this post here.

I've got an Outlaw about to be dropped into a .21 Maxx conversion. I'd really like to see better results from this new engine. The 2.5 was broken in per Traxxas' recommendations. :egad:

I'll consider this a tip from the pros. Traxxas only recommends two cool-down periods between the first three full tanks. And they don't specify that you'll do well by insuring the piston is at BDC.

 

[SkyMaxx]

If you look at most break in instructions, they are a tacit attempt at heat cycling. So the correct answer to this is to do the heat cycle methof. If Mr Bess has a proven method, follow it.

I heat cycled my Hyper after a single tank at idle, and the thing rocks. I heat cycled my Fantom and it still rocks. I followed the TRAXXAS instructions for the TRX Pro and it sits in a bag waiting for a chance at reincarnation as a better engine.

You decide.

 

[Çh®i§tiªñ]

Could I do the same thing by throwing it in the oven a couple of times?

The only stupid question is one not asked......

Ok, maybe I just killed a whole heard of cats.......

 

[SkyMaxx]

Yes, you did.

And NO, you can't just throw it in the oven. The heat cycling must be while the parts are in motion...wouldn't recommend throwing a lit engine in the oven...might get more bang for your buck than you want.

 

[wdavidhicks]

Can we pull Christian's admin privileges?

I gotta lotta cats in the neighborhood and it's already starting to stink.

 

[Çh®i§tiªñ]

lol

I had to!

Sorry guys!

 

[FlyinRazorback]

Originally posted by SkyMaxx
And NO, you can't just throw it in the oven. The heat cycling must be while the parts are in motion...

What Sky meant to say is you can't just throw it in the oven, you have to stick your hands in the oven and turn the engine over with your hands.:flaming:

 

[SkyMaxx]

That's the ticket. See, clear as mud. Now go light up those gas grills and try a little bar-b-cue ...

 

[Çh®i§tiªñ]

ASSHOLES! I'm Chris' wife - he burned the skin all over his hands! He wanted me to say BLING BLING CHA CHING!

 

[wdavidhicks]

Allow me to introduce myself....

This is Christian's attorney...

Ms. Dewey from Dewey, Cheatham and Howe.

I would like to interview each of you personally and in private.

By the way, I have a nice ass.

 

[Çh®i§tiªñ]

Dew on the fur!

 

[RobH]

here a heat cycle question that i doubt anyone will have an answer for:

It seems big block break in procedures differ greatly from small block procedures. Is the heat cycle break-in suitable for both big blocks and small blocks?

*waits*

....

*the sound of crickets in the background*