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Breaking in new engine?

  • Thread starter Thread starter tom2001gt
  • Start date Start date Jun 19, 2004
T

tom2001gt

Founding Member
May 20, 2002
292
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16
Delran N.J.
Jun 19, 2004
#1
  • Jun 19, 2004
  • #1
Im putting my new motor in on friday how long should the break in period be before you take it to the track?
Tom
 

88stangmangt

Active Member
Nov 25, 2003
2,332
1
48
Stafford,VA
Jun 19, 2004
#2
  • Jun 19, 2004
  • #2
give it atleast 500 miles at all rpms but in short burst's then give her hell. i would also run FULL!!!!! synthetic right off the bat mile 1!!!!!!
 

maverick0716

Founding Member
Jan 12, 2002
3,924
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56
Chilliwack, BC, Canada
Jun 19, 2004
#3
  • Jun 19, 2004
  • #3
I've heard if you run non-synthetic for the first 1000 miles or so, it will break in the engine faster.....then just swap out and put in synthetic
 
M

motrV8ed

New Member
Dec 8, 2001
31
0
0
Hampton, VA
Jun 19, 2004
#4
  • Jun 19, 2004
  • #4
Run non-synthetic for the 1st 500-1000 miles then switch to synthetic, the full will help the rings seal better. When I got mine back in I went up to 3rd or 4th gear and then hit it to load the engine up to about 60-65. Did this about 10 times then drove it 1000 miles and changed the oil to synthetic. Your rings will seal about 85-90% within the 1st few 100 miles I think it is. So run it up to about 60 10 times in 3rd or 4th gear (can't remember which) then drive it normally but try to constantly change cruis RPM's. You don't want to break the engine in just cruising on the I-state at 55-60mph because the rings won't seal properly. They need to constantly be loaded and unloaded like city driving. Unless it's a race motor then just run the **** out of it!
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Jun 20, 2004
#5
  • Jun 20, 2004
  • #5
yep, run dino oil initially unless your engine builder specifically built the motor (rings and bores) for synthetic right off the bat (like vettes, etc have). you dont want to glaze the cylinder walls and such, as others said.

also, you will want to do some frequent oil changes initially, so cheap dino oil is great.
good luck.
 
6

67stang390

New Member
May 29, 2003
379
0
0
Seattle, WA(home) ASU(college)
Jun 20, 2004
#6
  • Jun 20, 2004
  • #6
Yeah, I'm gonna have to go ahead and disagree with you guys here... At first I thought that rings needed to seat properly at various speeds, etc. for a few hundred miles. I just had my 347 rebuilt with new rings about a month ago (due to bad machining on the block, very long story). Normally I do all the work myself with my dad, but my motor took a dump on me when I was at college 1500 miles away from home. Duffee Motorsports in Phoenix rebuilt my motor and when I picked the car up, I asked how long it would take the new rings to properly seal. The (very qualified) mechanics at the shop said that every piston ring manufacturer they had ever spoken to say that piston rings are basically sealed after the first minute or two of running the engine. I drove it like I stole it straight out of that shop, revving it up beyond 6k numerous times, and 2000 miles later it still runs beautifully.
 

samuraichamploo

Member
Mar 18, 2004
367
0
16
Beaumont, TX
Jun 20, 2004
#7
  • Jun 20, 2004
  • #7
thats the truth.
only ****ty rings requrie such a long break in period. o
 

TT91

Active Member
May 23, 2003
1,536
0
36
Paramus, NJ
Jun 20, 2004
#8
  • Jun 20, 2004
  • #8
saltymaz said:
thats the truth.
only ****ty rings requrie such a long break in period. o
Click to expand...
I agree, read here. Engine break in secrets..
 

dcrahn

Founding Member
May 24, 2002
224
0
0
Springfield, GA
Jun 20, 2004
#9
  • Jun 20, 2004
  • #9
The only break required is if you have flat tappet hydraulic or solid lifters, roller don't require breakin.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Jun 20, 2004
#10
  • Jun 20, 2004
  • #10
Once you've put it through a few heat cycles (50 miles maybe) - checked for leaks, any unusual noises, done any retorques you're gonna do - headers, lower intake, etc., and changed out the oil/filter to get rid of rebuild/ass'y lube debris, it's ready to run as hard or as little as you like.
 
T

tom2001gt

Founding Member
May 20, 2002
292
0
16
Delran N.J.
Jun 20, 2004
#11
  • Jun 20, 2004
  • #11
After reading engine breakin secrets I guess running it easy isn't the best thing for a new engine.
Thanks for everyones help
Tom
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Jun 20, 2004
#12
  • Jun 20, 2004
  • #12
Tom - running it easy until you're sure all is working correctly is a very good thing. But it won't take 500-1000 miles to determine that all is working right. You'll likely know that in the first 5-10 miles.
 

5.0 HOtrain

Founding Member
May 20, 2001
2,247
0
47
New Hampshire
Jun 20, 2004
#13
  • Jun 20, 2004
  • #13
my motor got about 15minutes run time on the dyno at around 2500rpms. Oil changed and screened for debris, oil fitler cut open and inspected, heads retourqued, and valve lash reset. After that 11 power pulls all the way up 6800rpms.
mike.
 
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