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Engine break in

  • Thread starter Thread starter Cobain03
  • Start date Start date Jan 21, 2006
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Cobain03

Active Member
Aug 27, 2003
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Lexington, Ky
Jan 21, 2006
#1
  • Jan 21, 2006
  • #1
whats a fair amount of time ot break in a new engine. i may be picking my engine up on monday and doing install monday through wensday or so. my goal is to have it dynoed on saturday since that is a local dyno day. Is it fesible? there is a 3 month warranty on the engine but i dont want to go there either lol
 

krash kendall

Active Member
Nov 19, 2004
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36
Aldergrove, B.C. Canada
Jan 21, 2006
#2
  • Jan 21, 2006
  • #2
Did you end doing the 289 or the 302? What all did you get done?
 

Cobain03

Active Member
Aug 27, 2003
996
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36
Lexington, Ky
Jan 21, 2006
#3
  • Jan 21, 2006
  • #3
complete rebuild of the 289. bored it 30 over and through in a mild cam.
 

malcons66

New Member
Dec 20, 2005
141
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Fort Lauderdale FL
Jan 21, 2006
#4
  • Jan 21, 2006
  • #4
i had the same thing done man. i was ultra safe and didnt run it hard for 300 miles...but for a dyno im not sure if you would have to break it in that long.
 

DJE55

New Member
Jan 20, 2006
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Maryland
Jan 21, 2006
#5
  • Jan 21, 2006
  • #5
You should be able to break in the motor in a matter of minutes. I broke my motor in on the dyno in less than an hour and we were making pulls that afternoon. Made a little over 500hp at the rear wheels in less than a few hours after we first cranked it.
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
Jan 21, 2006
#6
  • Jan 21, 2006
  • #6
assuming the rebuilder didnt break the cam in, then you need 20 min for cam break in(run at 2000 rpm minimum and dont let the engine idle in that period). after the cam is broken in you can dyno the engine.
 

iskwezm

10 Year Member
May 24, 2005
4,159
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79
Rowland Heights,California
Jan 21, 2006
#7
  • Jan 21, 2006
  • #7
question:why is it said to take it easy on a new engine, but its okay to put a load and dyno it???? I waited about 600 miles before jumping on mine and putting the blower belt on
 

cobains_dad

New Member
Jul 4, 2005
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Jan 22, 2006
#8
  • Jan 22, 2006
  • #8
i hope you guys are telling him right,he has invested alot of his money on the car!!
 
S

steel1212

Active Member
Jun 24, 2004
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Frankfort, Ky
Jan 22, 2006
#9
  • Jan 22, 2006
  • #9
I personally wouldn't dyno it right after its rebuilt. I took some time with my engine with non synthetic oils for about 300 miles then switched and took it to the track.
 

KillerKittyCat

New Member
Aug 24, 2003
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Hammer Down - Behind The Wheel
Jan 22, 2006
#10
  • Jan 22, 2006
  • #10
If you have the hydraulic lifter setup the take it easy. Break in at 2000 RPM or better for half an hour. If you went solid then nail it!!!
 

iskwezm

10 Year Member
May 24, 2005
4,159
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79
Rowland Heights,California
Jan 22, 2006
#11
  • Jan 22, 2006
  • #11
KillerKittyCat said:
. If you went solid then nail it!!!
Click to expand...
I hope people dont listen to you, a solid needs break in time too
 

iskwezm

10 Year Member
May 24, 2005
4,159
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79
Rowland Heights,California
Jan 22, 2006
#12
  • Jan 22, 2006
  • #12
steel1212 said:
I personally wouldn't dyno it right after its rebuilt.
Click to expand...
ditto
 

Cobain03

Active Member
Aug 27, 2003
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36
Lexington, Ky
Jan 22, 2006
#13
  • Jan 22, 2006
  • #13
alright, i'll wait a couple of weeks then
 

krash kendall

Active Member
Nov 19, 2004
1,258
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36
Aldergrove, B.C. Canada
Jan 22, 2006
#14
  • Jan 22, 2006
  • #14
cobains_dad said:
i hope you guys are telling him right,he has invested alot of his money on the car!!
Click to expand...

Ask the engine builder, he'll be the one doing the warranty work not us.

That said, whenever we have to get a new jug (cylinder) on the airplane, we have to run mineral oil in it for the first 50 hrs. before switching back to synthetic. Nothing to do with cars other than the fact that metal on metal needs to be broken in.
 
S

sportsroof69

Founding Member
May 21, 2002
231
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16
Huntsville, AL
Jan 22, 2006
#15
  • Jan 22, 2006
  • #15
I broke mine in on the dyno and haven't had any problems at all. We did 10 pulls to 6000 and 1 to 6300. The real important thing is to break the cam in during the first 20 minutes after first start.
 

malcons66

New Member
Dec 20, 2005
141
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0
Fort Lauderdale FL
Jan 22, 2006
#16
  • Jan 22, 2006
  • #16
to be safe man give it like 300 miles. or more. for the cam, headwork, and all that stuff i went 500. better safe than ...you know what im talking about.make sure you retiten everything after a long run because of the heat and everything. you dont want to leak anything because of the gasketcs breaking etc etc
 

67coupe351w

New Member
Jan 31, 2004
424
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Portland, OR
Jan 22, 2006
#17
  • Jan 22, 2006
  • #17
There are two basic theories. one says to baby the engine for xxx number of miles after the cam break in and the other says break the cam in and run the engine as hard as you can (WOT or dyno) within the first 3 hours or so of its life.

The theory behind running the engine hard is that under high load the rings seat into the walls better while the hone is still on them providing a better seal for the life of the engine. light load or no load simple wipes the hone off the wall.
 

iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
Jan 22, 2006
#18
  • Jan 22, 2006
  • #18
67coupe351w said:
There are two basic theories. one says to baby the engine for xxx number of miles after the cam break in and the other says break the cam in and run the engine as hard as you can (WOT or dyno) within the first 3 hours or so of its life.

The theory behind running the engine hard is that under high load the rings seat into the walls better while the hone is still on them providing a better seal for the life of the engine. light load or no load simple wipes the hone off the wall.
Click to expand...
makes sence....but will i try it?????????dont think so
 

65fastback2+2

New Member
Aug 4, 2003
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Louisville, KY
Jan 22, 2006
#19
  • Jan 22, 2006
  • #19
As long as your cam was broke in properly you are fine. I know a roller motor doesnt have a 20 minute cam break in period, but 20 minutes after first start on my new roller 5.0 I was manually shifting it up to about 6k rpm racing a few ricers on the streets ....motors actually break in best if you drive them like your normal driving habits....hence why I was racing mine immediately
 

65fastback2+2

New Member
Aug 4, 2003
1,229
0
0
Louisville, KY
Jan 22, 2006
#20
  • Jan 22, 2006
  • #20
67coupe351w said:
There are two basic theories. one says to baby the engine for xxx number of miles after the cam break in and the other says break the cam in and run the engine as hard as you can (WOT or dyno) within the first 3 hours or so of its life.

The theory behind running the engine hard is that under high load the rings seat into the walls better while the hone is still on them providing a better seal for the life of the engine. light load or no load simple wipes the hone off the wall.
Click to expand...

ya, ronstang advised me on the second method of running it WOT....that motor never ran bad...i would tell anyone to run it WOT and dont do the baby thing
 
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