Best form for break in of new engines. See link.
11-27-2007, 02:07 AM
#1
Rennlist Member
Thread Starter
Best form for break in of new engines. See link.
http://www.mototuneusa.com/break_in_secrets.htm
Check this out and please comment.
Check this out and please comment.
11-27-2007, 03:23 AM
#2
Drifting
Join Date: May 2006
Location: Melbourne
Posts: 3,481
Likes: 0
Received 0 Likes
on
0 Posts
I was always told high load modest rpm and no synthetic. so run in procedure on the street can get you into alot of trouble .
letting the engine see high vacuum kind of contradicts his ring pressure theory
letting the engine see high vacuum kind of contradicts his ring pressure theory
11-27-2007, 03:34 AM
#3
I've seen that site a few years ago. I haven't time to re-read it again just now but I always wondered how that theory would work with Turbo cars? aybe follow that procedure but without any boost?
11-27-2007, 04:06 AM
#4
Burning Brakes
Join Date: Mar 2007
Location: Nor Cal
Posts: 1,177
Likes: 0
Received 0 Likes
on
0 Posts
I think the bigger question is whether or not we can use this method in Porsche's. (944's 951's 968's)
None of them are new and no longer require breaking in.
I'm guessing the only time we can use this method, is if piston replacement is on the menu.
Right?
None of them are new and no longer require breaking in.
I'm guessing the only time we can use this method, is if piston replacement is on the menu.
Right?
11-27-2007, 04:59 AM
#5
Rennlist Member
Thread Starter
Yes sure, this is in the case of rebuilt engines and remember that many of these are now ductile iron sleeved with non stock pistons so not like running in a stock car w Alusil bores.
11-27-2007, 07:52 AM
#7
Three Wheelin'
Join Date: Aug 2003
Location: DFW
Posts: 1,641
Likes: 0
Received 0 Likes
on
0 Posts
Very interesting.
Several years ago I had to take a software training class and wound up talking about cars/trucks/motors with my instructor for hours on end. He had outfitted a stroked and built 540-ish CID Ford big-block with a Megasquirt injection system, then stuffed it into a mini-monster 4WD Ranger (had to move the firewall back), and tuned it with his own software. Yes, I met a computer-nerd/power-mad truck dude. He claimed an AWD dyno run displayed ~800hp. I did not personally see the dyno sheet, as he didn't have it on him, but later I spoke to some of his coworkers who had recently winessed him drifting into their uphill asphalt parking lot fully sideways, smoking all 4 off-road Super Swampers with ease.
Anyway, dyno claims aside, this guy absolutely insisted on the necessity of high-RPM break-in. "Rods stetch!" he told me. They stretch more at high RPM, and therefore the piston will travel a tiny bit higher up in the cylinder. Traditional low-RPM break-in does not allow that last little bit of travel to get touched, so that when you do finally hit WOT the rings will suddenly encounter a miniscule lip of un-broken-in cylinder.
Best case, the sharp edge of the ring gets a little damage and sealing effectiveness is reduced. Worst case, for which he used the example of a teenager buying an old lady's car that's never been close to redline for years and revving the **** out of it, enough ring damage can occur to kill compression and lose oil-control to boot.
So to sum up:
> The motorcycle guy's main reason (in link above) for high-RPM break-in procedure is to use full-load cylinder pressure for better 360 degree ring to cylinder contact during the critical initial ring-edge to honing-high-spots "first date".
> The crazy mini-monster Ranger guy's main reason for high-RPM break-in procedure is to break-in all available cylinder area including the uppermost rod-stretch @ full-load high-RPM-only zone.
I have to say that both are compelling reasons.
Note: motorcycle guy does make mention of Nikasil...
Several years ago I had to take a software training class and wound up talking about cars/trucks/motors with my instructor for hours on end. He had outfitted a stroked and built 540-ish CID Ford big-block with a Megasquirt injection system, then stuffed it into a mini-monster 4WD Ranger (had to move the firewall back), and tuned it with his own software. Yes, I met a computer-nerd/power-mad truck dude. He claimed an AWD dyno run displayed ~800hp. I did not personally see the dyno sheet, as he didn't have it on him, but later I spoke to some of his coworkers who had recently winessed him drifting into their uphill asphalt parking lot fully sideways, smoking all 4 off-road Super Swampers with ease.
Anyway, dyno claims aside, this guy absolutely insisted on the necessity of high-RPM break-in. "Rods stetch!" he told me. They stretch more at high RPM, and therefore the piston will travel a tiny bit higher up in the cylinder. Traditional low-RPM break-in does not allow that last little bit of travel to get touched, so that when you do finally hit WOT the rings will suddenly encounter a miniscule lip of un-broken-in cylinder.
Best case, the sharp edge of the ring gets a little damage and sealing effectiveness is reduced. Worst case, for which he used the example of a teenager buying an old lady's car that's never been close to redline for years and revving the **** out of it, enough ring damage can occur to kill compression and lose oil-control to boot.
So to sum up:
> The motorcycle guy's main reason (in link above) for high-RPM break-in procedure is to use full-load cylinder pressure for better 360 degree ring to cylinder contact during the critical initial ring-edge to honing-high-spots "first date".
> The crazy mini-monster Ranger guy's main reason for high-RPM break-in procedure is to break-in all available cylinder area including the uppermost rod-stretch @ full-load high-RPM-only zone.
I have to say that both are compelling reasons.
Note: motorcycle guy does make mention of Nikasil...
Trending Topics
11-27-2007, 07:57 AM
#8
Three Wheelin'
Join Date: Aug 2003
Location: DFW
Posts: 1,641
Likes: 0
Received 0 Likes
on
0 Posts
More thoughts: Damn, you better get your tuning quite right the very first time you fire the motor up so you can go WOT right away... a little bit of a gamble for some motors.
11-27-2007, 10:35 AM
#9
Addict
Rennlist Member
Rennlist Member
This is another topic that I think is the end users responsibility.
Based on bores being straight, either a finish pass or complete bore and finish for Alusil;
first 100/150 miles, no boost/WOT and 30wt dino oil, vary rpm
next 150 miles, I still like dino oil, 20/50, 6-8# boost, no WOT.
after...good vac, no leaks, no smoke - drive it - I still turn up the boost slowly after that, while tuning, usualy like to 15psi and then up to 17 or 18. That's been succesful for the few that we've done and two of these engines passed smog with no cat, MAFs, and larger injectors; just a HO.
Based on bores being straight, either a finish pass or complete bore and finish for Alusil;
first 100/150 miles, no boost/WOT and 30wt dino oil, vary rpm
next 150 miles, I still like dino oil, 20/50, 6-8# boost, no WOT.
after...good vac, no leaks, no smoke - drive it - I still turn up the boost slowly after that, while tuning, usualy like to 15psi and then up to 17 or 18. That's been succesful for the few that we've done and two of these engines passed smog with no cat, MAFs, and larger injectors; just a HO.
11-27-2007, 05:16 PM
#10
Rennlist Member
Thread Starter
11-27-2007, 05:19 PM
#11
Rennlist Member
Thread Starter
Actually he does mention Nikasil.
11-27-2007, 08:28 PM
#13
Rennlist Member
Thread Starter
Well it doesn't cover turbo's so I'd agree that you could run it on very little or no boost, but even with the ebc turned off and just running on the spring you will get a certain amount as you know.
The problem I see with this link is that "you're either with us or you're agin us" in that he says that if you don't do it his way that you are doing potential damage to the new engine. He does make some good points though??? Any more engine builders out there care to comment?
The problem I see with this link is that "you're either with us or you're agin us" in that he says that if you don't do it his way that you are doing potential damage to the new engine. He does make some good points though??? Any more engine builders out there care to comment?
11-27-2007, 08:35 PM
#15
Rennlist Member
Thread Starter
Well that's a good point. When they are broken in on the dyno or even at the track they are not done in the same way that 'Owners Manual' suggests so why do we accept these methods as being ok yet cast doubts over this guys suggestions. They're not so different are they?
